WO2002082751A2 - Instantaneous joint transmit power control and link adaptation for rts/cts based channel access - Google Patents
Instantaneous joint transmit power control and link adaptation for rts/cts based channel access Download PDFInfo
- Publication number
- WO2002082751A2 WO2002082751A2 PCT/SE2002/000706 SE0200706W WO02082751A2 WO 2002082751 A2 WO2002082751 A2 WO 2002082751A2 SE 0200706 W SE0200706 W SE 0200706W WO 02082751 A2 WO02082751 A2 WO 02082751A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- transmit power
- frame
- station
- rts
- cts
- Prior art date
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/38—TPC being performed in particular situations
- H04W52/46—TPC being performed in particular situations in multi hop networks, e.g. wireless relay networks
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/16—Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
- H04W28/18—Negotiating wireless communication parameters
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/06—TPC algorithms
- H04W52/08—Closed loop power control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/38—TPC being performed in particular situations
- H04W52/50—TPC being performed in particular situations at the moment of starting communication in a multiple access environment
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/54—Signalisation aspects of the TPC commands, e.g. frame structure
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W74/00—Wireless channel access, e.g. scheduled or random access
- H04W74/08—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access]
- H04W74/0808—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using carrier sensing, e.g. as in CSMA
- H04W74/0816—Non-scheduled or contention based access, e.g. random access, ALOHA, CSMA [Carrier Sense Multiple Access] using carrier sensing, e.g. as in CSMA carrier sensing with collision avoidance
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/16—Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
- H04W28/26—Resource reservation
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/06—TPC algorithms
- H04W52/10—Open loop power control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/06—TPC algorithms
- H04W52/16—Deriving transmission power values from another channel
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/24—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters
- H04W52/243—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters taking into account interferences
Definitions
- the invention relates to the field of wireless communications, in particular to transmit power control and link adaptation techniques and mechanisms.
- the IEEE 802.11 is a wireless LAN (Local Area Network) standard that has been standardized by IEEE (Institute of Electrical & Electronics Engineers).
- the IEEE 802.11 wireless LAN standard is currently undergoing a process of extending the standard with QoS (Quality of Service) features.
- QoS Quality of Service
- the objective is to enable, for example, computers or multimedia devices to communicate under QoS constraints.
- This standard extension goes under the name IEEE 802. lie and is managed by the so-called task group e, TGe.
- IEEE 802.11 The high rate PHY (physical layer) on the so-called 5 GHz band is called IEEE 802.11a and is based on OFDM (Orthogonal Frequency Division Multiplexing).
- IEEE 802.11b The corresponding so-called 2.4 GHz band PHY is called IEEE 802.11b and uses single carrier modulation schemes.
- IEEE 802.11 operates either in a DCF (Distributed Coordination Function) or a PCF (Point Coordination Function) mode.
- DCF Distributed Coordination Function
- PCF Point Coordination Function
- MACAW Multiple Access with Collision Avoidance for Wireless
- ACK link acknowledgment
- IEEE 802.11 Other ongoing standardization activities in IEEE 802.11 include the so-called TGh (Task Group h, i.e. , an IEEE task group for IEEE 802. llh) that has the objective of designing and including transmit power control (TPC), as well as distributed frequency selection (DFS), in IEEE 802.11a.
- TPC transmit power control
- DFS distributed frequency selection
- the reader is referred to the standard IEEE 802.11-1999 (which replaces IEEE 802.11-1997), the standard IEEE 802.11a-1999 (High data rate on the 5 GHz Band), and the standard IEEE 802.1 lb-1999 (High data rate on the 2.4 GHz Band) .
- Good and simple overviews may also be found in a) "Smart Antenna Systems and Wireless LANs", authored by Garret T. Okamoto and published by Kluwer academic publishers (ISBN 0-7923-8335-4), and "IEEE 802.11 Handbook, A Designers Companion", authored by Bob O'Hara and Al Patrick (ISBN 0-7381-1855-9).
- DCF Distributed Co-ordination Function
- CSMA/CA Carrier Sense Multiple Access/Collision Avoidance
- RTS-CTS message exchange A MIB (Management Information Base) attribute "dotllRTSThreshold" is used to differentiate the use of the two.
- MPDUs MAC Protocol Data Units, where "MAC” stands for Medium Access Control
- RTS-CTS based CSMA/CA The focus here is the RTS-CTS based CSMA/CA mechanism that enables mitigation of hidden stations and hence in general provides a more efficient use of the wireless medium.
- Figures 1 A-1D show a communication procedure between a station
- station T transmits an RTS (Request to Send) signal to the station R.
- the transmit range 102 of the station T encompasses the stations R, E and F, but not the stations H, G.
- the stations R, E and F receive or overhear the RTS signal, but the stations H, G do not.
- Figure IB in reply to the
- the station R sends a CTS (Cleared to Send) reply signal to the station T.
- the transmit range 104 of the station R encompasses the station F, H but not the stations E, G.
- the station T After receiving the CTS signal, in Figure 1C the station T transmits a DATA signal to the station R, and then in Figure ID the station R acknowledges receipt of the DATA signal by sending an ACK signal or message to the station T.
- station H Since the station H is a hidden station with respect to the station T, it is informed of the intention of station T to transmit via the reply CTS message sent by the station R (since station H is not hidden from the station R, i.e. , it is within the transmit range 104 of the station R). As a consequence, the station H will not transmit and disturb ongoing reception by the station R. Stations E and F will in a similar manner defer channel access to the stations T and R, after overhearing the RTS from the station T and/or the CTS from the station R. As shown in Figures 1A-1D, station G is hidden from both stations T and R, and therefore will likely not overhear the RTS or CTS, and therefore it may transmit.
- Figure 2 illustrates frame formats used in IEEE 802.11, where the numbers above the boxes indicate the size of the information in the box. Note, Address 4 in the DATA and MANAGEMENT frame exists only for DATA frames in a wireless DS (Distribution System), and does not exist in MANAGEMENT frames.
- Address 4 in the DATA and MANAGEMENT frame exists only for DATA frames in a wireless DS (Distribution System), and does not exist in MANAGEMENT frames.
- Figure 3 illustrates the frame exchange including RTS and CTS.
- NAV Network Allocation Vector
- This provides an additional collision avoidance mechanism to the physical channel access sensing and is therefore called virtual channel sensing.
- a station must remain silent When the channel becomes free, stations start contending for the channel according to the channel access principles defined in the IEEE 802.11-1999 standard.
- the NAN can only be extended if new frames are received. There exist some special instances when the NAV can be reset as well, but that is not the normal operation.
- FIG. 4 illustrates use of RTS-CTS with DATA fragmentation. Each fragment and ACK then acts as implicit RTS and CTS. Additional fragments are indicated by a bit (field) in the frame control of the fragments.
- CTS should be sent with the same link rate as RTS
- ACK should be sent with the same link rate as DATA.
- the original purpose is to enable the originating or transmitting station (e.g. , the station T of Figure 1) to calculate the duration value prior to RTS transmission.
- FIG. 5 shows a detailed example of two stations attempting to access a channel through the RTS-CTS phase.
- each time slot 9 microseconds
- the SIFS (Short Inter-Frame Spaces) time 16 microseconds
- a min CW (Contention Window) 15 time slots
- a max CW 1023 time slots
- RTS 52 microseconds @ 6 megabytes/second
- RTS 24 microseconds @ 54 megabytes/second
- WO-9501020 A discloses that each station in a wireless LAN (Local Area Network), using time-distributed multiple access control, listens to traffic using the network communications channel, for example, for spread-spectrum, frequency-hopping transmissions. Each station constructs its own network allocation vector from the received transmission contents, indicating when the channel will be in use.
- Message transmission uses four- way handshaking with two short control packets, "Request to send” (RTS) and "Clear to send” (CTS).
- RTS Request to send
- CTS Charge to send
- the RTS packet includes the data transmission length, enabling the various receiving stations in the network to reserve and block their use of the communications channel over the period of time concerned.
- the CTS packet repeats this data length, for the benefit of receiving stations not within range of the source transmission.
- This document corresponds to the IEEE 802.11 standard defined in the IEEE 802.11-1999 standard.
- Busy Tone Multiple Access are described in S.-L. Wu, Y.-C. Tseng, and J.-P. Sheu, "Intelligent Medium Access for Mobile Ad Hoc Networks with Busy Tones and Power Control", IntT Conf. on Computer Communications and Networks, 1999, pp. 71-76.
- DBTMA is an extension of BTMA with dual busy tones instead of a single busy tone.
- BTMA Bussy Tone Multiple Access
- TP Maximum Transmit Power
- Another drawback is that information regarding fixed TP is assumed known at the receiver.
- DBTMA with TPC only attempts to solve a problem in a specific situation, namely in a distributed system where stations are neither associated with APs, nor associated in a group with other stations.
- Another drawback is that asymmetries in interference, link gain, or TP capabilities are not been considered.
- Exemplary embodiments of the invention take a more far-reaching transmit power-control (TPC) approach than outlined IEEE 802.11 TGh, and have the objective of improving the overall system performance in IEEE 802.11a as well as other RTS-CTS based channel access scheme to the greatest feasible extent In doing so, this will implicitly address QoS goals considered in IEEE 802.11 TGe.
- TPC transmit power-control
- a further goal of the invention is to address the issue of link adaptation (LA) in conjunction with RTS-CTS frame exchange.
- a further goal of the invention is to address the issue of link adaptation (LA) in a common framework with TPC.
- a method for closed loop link adaptation based on a Request To Send-Clear To Send (RTS-CTS) channel access scheme includes the following steps. Designating a station as an originating station. Transmitting a RTS frame with predetermined transmit power from an originating station, prior to an intended DATA transmission, sounding the channel such that reception characteristics can be evaluated at a designated receiving station. Transmitting, in response to the originating station, a CTS frame with a predetermined transmit power from the receiving station with directives of link adaptations. Transmitting a DATA frame from the originating station to the receiving station frame complying with link adjustment directives to the extent of the originating stations capabilities.
- RTS-CTS Request To Send-Clear To Send
- a method for open loop group transmit power control in an infrastructureless system includes the following steps. Transmitting a frame conveying transmit power information for the corresponding frame to any proximate station. Receiving, by one of the proximate stations, the frame and determining the path gain based on measured signal strength of the received frame and respective transmit power information conveyed in the received frame. Selecting path gains originating from the same group (i.e. , IBSS). Determining a required transmit power to reach nodes associated with any of the selected path gains.
- a method for open loop group transmit power control in an infrastructure system includes the following steps. Selecting, by an access point (AP), at least one station within a group. Transmitting a transmit power information request from an AP to the at least one selected stations. Transmitting a transmit power response with transmit power information for the corresponding frame to any proximate station from the at least one selected stations in an orderly manner preventing collisions. Receiving the frame with the transmit power response and determining the path gain based on measured signal strength of the received frame and respective transmit power information in the received frame. Selecting path gains originating from the same group (i.e., BSS).
- Determining required transmit power to reach nodes associated with any of the selected path gains Selecting the minimum of the highest transmit power and allowed transmit power, wherein the allowed transmit power is determined by regulatory requirements and stations transmit power capabilities. Assigning the selected transmit power to Request To Send (RTS), Clear To Send (CTS) messages and other frames destined for nodes associated with any of the selected path gains.
- RTS Request To Send
- CTS Clear To Send
- a method of tiered transmit power includes the steps of determining a sequence of frames that must be exchanged for successful communication, and assigning different transmit power levels to those frames wherein the frames have different topological objectives or distance objectives.
- a method for interference mitigation based on open loop transmit power control enabling tighter medium reuse includes the following steps. Conveying transmit power control information for and in every transmitted frame by any station transmitting. Receiving frames and determining a path gain based on measured signal strength of the received frames and respective transmit power information conveyed by the received frames. Determining the maximum instantaneously allowed transmit power based on all overheard frames such that ongoing communication is not noticeably disturbed. Conditioning transmit power, and if feasible and necessary, reducing transmit power and other transmit parameters (e.g., link rate etc), to ensure that the maximum transmit power condition is not exceeded during any transmission attempt.
- transmit power control information for and in every transmitted frame by any station transmitting.
- FIGS 1A-1D show an RTS-CTS-DATA-ACK message exchange.
- Figure 2 shows exemplary MAC Frame formats of IEEE 802.11.
- Figure 3 shows NAV setting together with RTS-CTS.
- Figure 4 shows NAV setting when fragmentation is employed together with RTS-CTS.
- Figure 5 shows two sources or originating stations/nodes attempting to access the same channel in IEEE 802.11a.
- FIG. 6 shows an example of a Tiered TPC in an IBSS-like system in accordance with exemplary embodiments of the invention.
- Figure 7 shows an example of Joint TPC and LA on DATA with an optional extension to ACK in accordance with exemplary embodiments of the invention.
- FIG. 8 shows TPC information derived from a BEACON in IBSS in accordance with exemplary embodiments of the invention.
- Figures 9A and 9B show IBSS path gain estimates from a BEACON in accordance with exemplary embodiments of the invention.
- Figure 10 shows a Request for TP Information issued by an AP and responded to by an addressed station in accordance with exemplary embodiments of the invention.
- Figure 11 shows an example of BSS TPJRequest, TP_Reply exchange that establishes path-gain knowledge in accordance with exemplary embodiments of the invention.
- Figure 12 shows exemplary TP_Request and TP_Reply IEs in accordance with exemplary embodiments of the invention.
- Figure 13 shows concurrent and adjacent DATA transmissions enabled by TPC in accordance with exemplary embodiments of the invention.
- Figure 14 shows an interference profile at a receiving station in accordance with exemplary embodiments of the invention.
- Figure 15 shows exemplary frame formats including Closed Loop TPC and LA in accordance with exemplary embodiments of the invention.
- Figure 16 shows exemplary frame formats including TP Information fields in accordance with exemplary embodiments of the invention.
- Figure 17 shows a frame format including a generic field for TP and LA information in accordance with exemplary embodiments of the invention.
- Figure 18 shows a table describing a TPC policy following a tiered approach in accordance with exemplary embodiments of the invention.
- FIG. 19 shows a Transmit Power Information Request Element format in accordance with exemplary embodiments of the invention.
- Figure 20 shows a Transmit Power Information Element format in accordance with exemplary embodiments of the invention.
- Figure 21 shows BEACON modifications in accordance with exemplary embodiments of the invention.
- Figure 22 shows Probe Request modifications in accordance with exemplary embodiments of the invention.
- Figure 23 shows Probe Response modifications in accordance with exemplary embodiments of the invention.
- Figure 24 shows a P ⁇ x Request format in accordance with exemplary embodiments of the invention.
- ERC European Radiocommunications Committee
- EIRP Effective Isotropically Radiated Power
- DFS Distributed Frequency Selection
- TPC Transmit Power Control
- IEEE 802.11 devices operating in the ERC area must therefore comply with stated conditions.
- the IEEE 802.11 standard currently does not incorporate the required TPC mechanisms, it is an objective of exemplary embodiments of the present invention to present methods with respect to TPC, such that ERC directives can be fulfilled. In doing so, it is a further objective of exemplary embodiments of the present invention to provide TPC methods enabling link and system performance enhancements.
- Exemplary embodiments of the present invention can be applied in both infrastructure-based 802.11 WLANs with an AP (Access Point), or Infrastructure BSS (Basic Service Set), as well as ad hoc-oriented 802.11 networks, or independent BSS (IBSS).
- DCF Distributed Coordination Function
- AP Access Point
- IBSS Independent BSS
- DCF Distributed Coordination Function
- E Point Coordination Function
- HCF Hybrid Coordination Function
- Exemplary embodiments of the present invention enable not just compliance with ERC requirements, but also enable significant enhancement of system performance in terms of throughput, delay and prolonged battery life. Exemplary embodiments of the present invention also provide mechanisms and procedures to implicitly enhance experienced QoS (Quality of Service) as well as reduce the need for overlap BSS handling.
- TPC for IEEE 802.11 is proposed with some modification in the current 802.11 MAC specification that may be incorporated as part of the changes within the 802. lie framework.
- methods, protocols and frame structures are disclosed that enable both joint and independent TPC and LA (Link Adaptation) in conjunction with a RTS/CTS based channel access scheme.
- Group based TPC mechanisms for frames like RTS and CTS are provided.
- group is synonymous with the collection of all stations in a BSS or in an IBSS, but can also be interpreted in other groupings not specified by or explicitly defined in IEEE 802.11.
- Exemplary embodiments of the present invention also provide a TPC mechanism for interference mitigation, such that stations belonging to other Groups (BSSs or IBSSs, where "BSS” stands for Basic Service Set and "IBSS” stands for Independent Basic Service Set) are not interfered with. At the same time this enables reuse of the channel provided a suitable TP (Transmit Power) level is selected.
- TP Transmit Power
- Interference mitigation mechanisms may alternatively be employed within a group, e.g., an infinite large and dispersed group.
- both closed loop as well as open loop TPC are applied.
- TPC open loop
- the RTS and CTS frames may, depending on the adotllThreshold value, be relatively prevalent and hence considered as important contributors to undesired interference and power ⁇ onsumption.
- One aspect of the mvention is to enable a tiered TPC policy in a CTS/RTS based channel access system.
- the motivation for this is that different topological and communication range aspects need to be met depending on frame type. Note that those frames, as the one in IEEE 802.11, have a timely and logical relation to each other.
- the TPC policy follows a tiered approach defining three levels. Frames with different topological destination objectives are divided among those three Tier-classes. Figure 18 shows the three major TPC tiers.
- Tier 1 frames are sent with high transmit power
- this class also adopts a policy of being constrained in time. The reason is to minimize random interference peaks within and towards neighboring (I)BSS. This may be achieved by confining Tier 1 traffic around Beacon transmit occasions, i.e. sent regularly around TBTT (Target Beacon Transmission Time).
- Tier 1 Beacon TPC, the BEACON frame as defined in the IEEE 802.11-1999 standard, and other conceivable frames/messages with similar topological destination purposes, must generally reach as far as possible. However, those must also conform to regulatory requirements in terms of used TP. As in the IEEE 802.11-1999 standard, such messages are often scheduled at regular time intervals and having priorities above other traffic and may therefore transmit at fixed but the highest permitted TP.
- Tier 2 relating to RTS, CTS and TPC, two major embodiments or cases exist.
- Fixed TPC, RTS/CTS are sent with the highest possible TP, but are limited by regulatory TP requirements.
- the TP setting is identical to the Beacon information.
- the purpose of this embodiment is to be able to inform distant stations of ongoing DATA transmissions such that they can select DATA transmit parameters that will mitigate generation of disturbing interference.
- RTS/CTS frames could, in principle, be sent in a special control channel separated from data transmissions, hence avoiding interfering with said data transmissions.
- Group TPC the RTS and CTS are sent with a sufficiently high TP so as to reach members or stations within the same group/BSS, but preferably with a sufficiently low TP so as to a) not reach members within another group, and b) stay within regulatory TP requirements and limits.
- one purpose is to reduce the interference impact on other stations' DATA transmissions due to RTS/CTS message exchange, when RTS, CTS messages are sent in the same channel and potentially concurrently with DATA transmissions.
- FIG. 5 shows a case where two IEEE 802.11a stations belonging to the same group attempt to get control over the medium by sending RTSs and CTSs, with link rates of 6 Mbps. Due to unfortunate time relations between the duration of the RTS start to the CTS end, in relation to 802.1 la's timeslot (TS) structure, the virtual carrier sense for source 1 (assumed hidden to source 2) will only work roughly 12 TSs after source 2 accessed the medium first. However, the physical carrier sense of source 1 would need roughly 8 TSs to detect the CTS from destination 2.
- TS timeslot
- RTS-CTS phase is housed within a single time slot, so that the TPC can also rely on the relaying function through the CTS frame.
- group based TPC is performed for the CTS message, while applying a lowest possible TP for the RTS frame.
- This primarily targets the case where the RTS-CTS phase can be housed within a single TS, i.e. not a IEEE 802.11a system. The motivation for this is that DATA reception is more vulnerable than the reception of ACKs, due to the potentially longer interference exposure time for the DATA frame.
- ACK TPC + LA for DATA transmission an Instantaneous Closed Loop TPC and Instantaneous Closed Loop LA is deployed via feedback information conveyed in the CTS messages.
- DATA TPC also conforms to regulatory aspects as well as the RTS/CTS TPC setting.
- TPC and LA Link Adaptation
- ACK generally follows the parameters for DATA.
- a special case is fragmented transmission when DATA and ACK headers acts as implicit RTS and CTS messages. Then the DATA, ACK and TPC may optionally become equivalent to RTS, CTS and TPC.
- the tiered TPC policy can be summarized as:
- FIG. 6 An illustrative but simplified example of an IBSS-like system is shown in Figure 6, which illustrates how different TP settings for different frames result in different transmit ranges.
- the second embodiment of Tier 2 i.e. , Case 2 of RTS-CTS TPC
- the ring 102 is the DATA transmission range for the station T
- the ring 104 is the DATA transmission range for the station R
- a ring 212 is the RTS transmission range for the station T
- the ring 214 is the RTS transmission range for the station R.
- the rings 212, 214 are larger than the rings 102, 104.
- each node or station receiving an RTS message assesses preferably the instantaneous carrier to interference ratio, CIR, and other channel parameters of choice. Subsequently, a desired reduction or increase of transmit power used for the RTS frame is determined. A relative transmit power adjustment request P TX Request is then conveyed in the CTS message back to the originating station. The originating station adjusts the transmit power level accordingly for the subsequent DATA frame transmission. The same procedure is repeated for the ACK, i.e., the originating station conveys a corresponding transmit power adjustment request targeted for the ACK. Note that both RTS and CTS are sent with TPC Tier 2 related mechanisms described further below.
- LA for DATA consider the following example. Assuming that a station T has a data packet to send to a station R and that the employed channel access scheme with back off and similar features has already acted, the station T sends a RTS message with a TP of P TX (RTS) to station R. This transmission can be conditioned so that it does not harm any ongoing communication.
- RTS P TX
- Station R receives the RTS frame and determines the received power P TX (RTS) and other optional link characteristics that can provide additional guidance to the LA and the TPC algorithms.
- Optional link characteristics may include channel state information or simply delay spread information.
- the station R also experiences and measures interference 1 ⁇ at the same time from some other station(s) and other interference characteristics that can provide additional guidance to the LA and the TPC algorithms.
- P RX RTS
- RTS RTS
- interference l ⁇ with other interference characteristics and knowledge about noise
- link, interference and noise knowledge are used by the station R to determine changes in TP relative the TP employed for the RTS message, for example closed loop with signaling of relative change.
- link, interference and noise knowledge are used by the station R to determine settings of the LA based on the TP employed for the RTS message.
- both LA and TP settings are determined by the station R.
- determined link control information is transferred in the CTS frame to the station T.
- the CTS transmission can be conditioned so that it does not harm any ongoing communication.
- the station T uses the settings indicated in the link control information received in the CTS message when sending DATA. This transmission can be conditioned so that it does not harm any ongoing communication.
- the procedure is repeated for successive and consecutive frame exchanges.
- the DATA frame carries link control information for the ACK frame that adjusts its TP relative the CTS message.
- the ACK rate can be adapted as determined by the originating station T in future systems.
- DATA and ACK act as RTS and CTS frames and will then convey link control information where the power control also relates to the last sent frame.
- the RTS and CTS messages are sent with duration field indications covering the expected duration. This transmission can be conditioned so that it does not harm any ongoing communication.
- Figure 7 shows the principle of closed loop joint TPC and LA based on RTS-CTS frame exchange.
- Option 1 allows an adaptation of TP and LA for the ACK. Note that according to the IEEE 802.11-1999 standard, DATA and ACK should use the same LA scheme. However, future extensions or the development of similar systems are not excluded.
- a first step 702 the originating station T sets RTS power to P TX (RTS), and then in step 704 sends the RTS to the station R.
- the station R measures P RX (RTS) and I RX , and determines P TX (DATA) and LA(DATA) and then conveys the determined information in the CTS in step 708 to the station T.
- the station T makes adjustments according to the determined P TX (DATA) and LA(DATA) received in the CTS.
- the station T also measures P RX (CTS) and I ⁇ , determines P ⁇ ACK) and LA(ACK), and then adds this determined information into the DATA.
- the station T transmits the DATA to the station R.
- the station R makes appropriate adjustments if the received data included P TX (ACK) and LA (ACK), and then in step 716 the station R sends an ACK to the station T.
- a first option follows the legacy channel access principle for IEEE 802.11, i.e., when the physical or the virtual carrier sense indicates that the channel is occupied, access is deferred.
- a drawback of this state of the art technique is that it does not attempt to reuse the channel even when it would be possible as TPC is employed.
- a second alternative option in accordance with exemplary embodiments of the invention exploits overheard information of TP indications and maximum allowed receive power.
- Such information may be included in, and derived from, the header information of primarily RTS and CTS frames, but also DATA, ACK and possibly other frames.
- This scheme is described in greater detail further below, and is also referred to as Interference Mitigation.
- the allowed transmit power level allows domain specific settings. Each station within an (I)BSS uses the allowed domain transmit power when sending a frame containing any of the appropriate IEs defined in Figures 19-23. If the transmit power capability is lower than the domain transmit power level, the former will be used.
- the setting of Beacon TP is determined by IEEE 802.11 management information base, MIB of the node initiating a (I)BSS.
- MIB IEEE 802.11 management information base
- the TPC setting for the BEACON is distributed as an Information Element, IE, conveyed in the BEACON itself.
- IE Information Element
- the aim is to determine a transmit power setting such that all stations or nodes within an (I)BSS will have a sufficient CIR to be able to receive frames.
- This mechanism is also useful for TPC setting for broadcast and multicast traffic within the (I)BSS, but it is primarily aimed towards RTS and CTS frames.
- the RTS-CTS frame exchange efficiently prevents hidden stations from accessing the channel, further enhanced by the virtual carrier sense, the RTS-CTS frames themselves need to be protected with classical physical carrier sense. As a result, it is vital to ensure that all stations within the same (I)BSS transmit with sufficient power so as to reach each other. However, from the viewpoint of interference and power consumption, it is preferred to send with the least possible transmit power.
- the Group oriented TPC proposed here intend to strike a balance between those two somewhat conflicting goals.
- a first case is Fixed TPC.
- CTS messages is lower than if the channel is shared.
- the channel can be considered not to be shared when RTS, CTS are separated e.g. , in time (as for example in a TDD/TDMA structure, where "TDD” stands for Time Division Duplex and "TDMA” stands for Time Division Multiple Access), in code (as for example in DS-CDMA, which stands for Direct Sequence Code Division Multiple Access), or in frequency (as for example in FDD, where "FDD” stands for Frequency Division Duplex).
- a drawback with the frequency division is that the channel cannot be considered to be reciprocal, and hence the channel gain may differ for RTS, CTS and DATA channels.
- An additional method to mitigate interference influence from RTS, CTS messages when sharing the channel with DATA is to use a strong burst error correcting code for DATA.
- a strong burst error correcting code for DATA As an example, an Reed-Solomon (RS) code of length N RS-symbols with N-K RS-redundant symbols, may correct up to floor ((N-K)/2) unknown RS-symbols or floor((N-K)) known erroneous RS-symbols.
- RS Reed-Solomon
- the TPC regulates the TP preferably to the permitted level according to regulatory requirements and attainable by the equipment itself. Note that BSS- and IBSS-like systems do not need to be differentiated from TPC point of view here.
- a second case is Group TPC. In order to handle both BSS- and IBSS-like systems two methods are deployed.
- the procedure for IBSS Group TPC is based on conveying transmit power level information, P TX , as an information element, IE, in the regular IBSS Beacon.
- P TX transmit power level information
- IE information element
- P ⁇ x merely represents the transmit power employed for the frame in which the IE itself is transferred within.
- the intent of using the Beacon is because it complies well with both power sleep mode operation as well as the Tier 1 objectives.
- a minimum required receive power level, P RX mn is sent in the same IE.
- Each station receiving a Beacon with the IE determines path gain and subsequently required transmit power. Each station also assess that the Beacon originates from a station within the same IBSS. Over the time, as the IBSS Beacon transmit time is somewhat randomized, Beacons from all stations within the same IBSS and within range will be received. Based on the collated information, the maximum required transmit power is selected among the stations. Old transmit power updates lose validity over time as new updates are not overheard.
- each STA (station) will attempt to transmit a BEACON frame at the TBTT plus a random small delay. A STA overhearing another BEACON refrain from transmitting. As the BEACON is transmitted with relatively high power, all STAs within the IBSS have sufficient SNR (Signal to Noise Ratio) to correctly decode the message except collisions occur where decoding may fail.
- SNR Signal to Noise Ratio
- An additional IE (apart from already existing in the IEEE 802.11-1999 standard) indicates the TP level, P TX (BEACON), that is used when sending the BEACON.
- the IE is incorporated into the BEACON frame itself, as shown for example in Figure 21.
- P TX (BEACON) and the received signal strength P RX (BEACON) derived from the BEACON frame is known, the path gain can be calculated. This is repeated for all received BEACONS. The minimum path gain from any STA belonging to the same IBSS is subsequently extracted and used to calculate the TP for the RTS and CTS message.
- the TPC Group procedure described below is used when STAs require different minimum receive power.
- An advantage of exploiting the BEACON is that Power Save enabled STAs wake up and listen for the BEACON.
- FIG 8 shows a station sending one BEACON that is received by a number of other STAs within the same IBSS.
- a BEACON sending STA (station) first sets P TX (BEACON) to a maximum allowed level, and indicates P TX (BEACON) in the BEACON.
- the BEACON sending STA (station) also determines P RX Mn , and also indicates P ⁇ ⁇ [ ⁇ n in the BEACON.
- the station sends the BEACON to other STAs (stations), and each of the other stations measures P RX (BEACON) and then determines path gain and required transmit power.
- FIG. 9A-B An alternative view of the effect of receiving the BEACON with TPC information conveyed therein is shown in Figures 9A-B.
- the ring 902 indicates a BEACON transmit range of the station or node C, and G CA , G CB , G CE , G CF and G CG respectively represent the path gain from the node C to each of the nodes or stations A, B, E, F and G.
- each STA will have knowledge about average path gain to each STA, from which they received BEACON(s), within the same IBSS, and possibly also other IBSSs.
- FIG. 9B indicates the path gain knowledge acquired by station B, with path gains G AB , G CB , G FB , G GB between the station B and the stations A, C, F and G respectively.
- the weight of old path gain information is assumed to decrease.
- BSS group TPC With respect to BSS-like systems in Group TPC, the procedure for BSS group TPC is somewhat similar to the procedure for IBSS, but the channel probing sequence is directed by the AP.
- a transmit power information request directed towards a selected STA is issued by the AP. This request is sent via an IE, e.g., carried in a Probe request or other suitable frame, e.g. , just immediately after the Beacon.
- a Probe response or other suitable frame is sent back from the addressed STA with another IE indicating the used transmit power information P ⁇ x and preferably also a minimum required receive power level, P RX ⁇
- the Probe request and Probe response employs the Tier 1 TPC setting rule.
- Each STA receiving the Probe response (or alternative suitable frames) with the IE determines path gain and subsequently required transmit power.
- Each STA also assess that the frame originates from a STA within the same BSS. Over the time, frames with the desired IE from all STAs within the same BSS and within range are received. For each individual STA, the maximum required transmits power is then selected among the STAs with respect taken to changing channel gain over time.
- the polling sequence of STAs belonging to a BSS is an implementation specific issue and not defined in the standard. Note that the scheme allows those implementing the scheme to adjust P RX a ⁇ n and manage the algorithmic dynamics in any desirable manner. Note also, that by regulating P R i n ' stations will try to adaptively compensate desired receive power in the presence of an adjacent interfering BSSs. Hence if maximum domain transmit power is the optimum, the system will tune transmit power parameters accordingly. In contrast, other situations will conserve the resources instead. Moreover, as Tier 1 information shall not interfere with Tier 2 traffic, due to timely division, interference measurement guiding the setting of P RX I ⁇ n should preferably exclude Tier 1 related interference.
- the AP sends the BEACON, whereas non-AP STAs does not send any BEACON, and as a result, the IBSS solution does not work.
- the AP performs a TP_Request of non-AP STAs. It requests one or more STAs that belongs to the BSS to send a TP_Response with corresponding TP setting conveyed therein.
- the TP_Response is preferably sent with the same TP setting as the BEACON is using.
- STAs within a BSS may use any transmit power indication in the BEACON to determine required transmit power towards the AP.
- a specific TP_Request message is defined as one IE.
- Another IE is used for TP_Response, indicating the used TP level for the same message it is conveyed in.
- the TP_Request IE can e.g., be included in a BEACON, PROBE_REQUEST, or a so-called GENERIC_MANAGEMENT_FRAME that is currently under development in the standardization of IEEE 802.11 enhancements.
- the TP_Res ⁇ onse IE can e.g. , be included in a PROBE REQUEST, PROBE RESPONSE or a so-called GENERIC MANAGEMENT FRAME.
- the TP polling scheme of the AP can for example be accomplished in a round robin fashion or targeted in particular towards STAs expected to be at coverage boarder.
- TP will be set to the same level as the BEACON TP level for the RTS-CTS frames.
- the IE includes not just the used TP P TX (FRAME), but also a measure of the minimum required receive power P RX pest,; theory.
- FRAME TP P TX
- a known lowest link rate is assumed when defining P RX ⁇
- Figure 10 shows an exemplary case where an AP issues an
- TP_Request IE in a BEACON As shown in Figure 10, in step 1002 a BEACON sending AP (Access Point) selects one or optionally more stations (STAs), and indicates a TP_Request IE in the BEACON. Then in step 1004, the AP sends the BEACON to the selected, addressed station(s). In step 1006 the addressed station ⁇ responds to the request by a) setting P TX (FRAME) to a maximum allowed level, b) indicating the P TX (FRAME) in an IE TP_Response, c) optionally determining P R m i n an( i indicating the determined P RX r ⁇ n in the IE TP_Response.
- the addressed station issues the TP_Response IE in any suitable frame type. If multiple stations were addressed, they respond in an orderly fashion according to address sequence. Each frame is divided a SIFS (Short Inter-Frame Space) apart.
- SIFS Short Inter-Frame Space
- the other stations receiving the frame(s) containing the TP_Res ⁇ onse IE(s) measure the P RX (FRAME), and determine path gain and required transmit power (and optionally include explicit P ⁇ min information in the transmit power determination if Pgx ⁇ is received in the TP_Res ⁇ onse IE).
- FIG. 11A An alternative view of the TP_Request and TP_Response exchange is shown in Figures 11A-B with the calculated path gain indicated.
- station C is an AP and has a transmit range indicated by the ring 1102, and path gains G CA , G CB , G CE , G CF and G CG from the station C to each of the stations A, B, E, F and G respectively.
- Figure 11A also shows a TP request sent from the station C (AP) to the station G.
- Figure 11B shows a similar situation, but from the vantage point of the station G.
- the ring 1104 indicates the transmit range of the station G, and the path gains G GA , G GB , G GC , G GE and G GF from the station G to each of the stations A, B, C (AP), E, and F respectively are shown. Also shown is a TP Response from the station G to the station C (AP).
- FIG. 12 shows the content of the TP_Request and TP_Re ⁇ ly IE, and their place in a management frame body of arbitrary type.
- the Management Frame Body 1204 includes multiple Fix fields, and also multiple IEs.
- Each IE has a format 1206, including an Element ID of 1 octet or byte, a Length field of one octet, and an Information field having a length indicated in the Length field.
- TP_Request is only used in BSS operation.
- the table 1202 shown in Figure 12 describes an exemplary TP_Request format (corresponding to the Element ID x in the table), and describes an exemplary TP_Reply IE format (corresponding to the Element ID y in the table).
- Figure 20 also shows an exemplary Transmit Power IE (Information Element) format
- Figure 19 shows an exemplary Transmit Power Information Request Element format.
- Figure 21 shows how a Management frame subtype BEACON can be modified to include three new IEs, in accordance with exemplary embodiments of the invention.
- the 11 th IE in the frame can include Domain Information
- the 12 th IE in the frame can be a Transmit Power Information Request Element
- the 13 th IE in the frame can be a Transmit Power Information
- Transmit Power Information Request Element could also be included in other frames, such as management frames. Also note that Transmit Power Information Element could optionally also be included in the BEACON for a BSS.
- Figure 22 shows how a probe request can be modified in accordance with exemplary embodiments of the invention, to include a Transmit Power Information Request Element.
- Figure 23 shows how a probe response can be modified to include a Transmit Power Information Element.
- the policy of group TPC may be employed only towards the CTS frame, whereas the RTS frame employs a TP setting with respect to the intended receiver.
- the schemes depicted earlier for RTS, CTS TPC to acquire group TP level knowledge are hence used merely for the CTS frame.
- the RTS TP level is determined with an independent algorithm but limited upwards by the TP setting for the CTS frame. Any overheard messages carrying TP information (as described further above, for example) and sent by the intended receiver, may be used as inputs to determine the TP level for the RTS frame.
- An exemplary embodiment of the TPC group algorithm includes the following steps: Monitor the channel for messages carrying an IE indicating the TP of the corresponding frame. Next, determine if the IE was sent by a STA k belonging to the same (I)BSS (group) and if so, determine the required TP. If the IE includes interference information, this is also considered when determining the TP P TX (RTS) k .
- the TP is preferably determined for the lowest data rate, requiring the least TP and hence minimize generated peak interference.
- set P TX (RTS) max( P TX (RTS), ... P TX (RTS) k , ...
- P TX (RTS) K where k indexes stations (STAs) within the same (I)BSS (group).
- a procedure is provided to increase the spatial reuse through Open Loop Interference Mitigation Control as outlined below.
- a station or node can determine maximum permitted TP and can transmit frames without disturbing (to any noticeable degree) ongoing communication which would not be permitted under the current channel access rules in the IEEE 802.11-1999 standard.
- TP indications and maximum allowed receive power P RX MAX are included in, and derived from, the header information of primarily RTS and CTS frames, but also DATA and ACK frames.
- the maximum allowed receive power P RX MAX is related to the experienced interference and noise level. It is most important to include and detect the information in the CTS frame header as DATA reception is in general more vulnerable for interference compared to e.g., ACK, due to in general longer frames and possibly also higher required CIR resulting from higher link rates.
- P RX max can optionally be determined from the P ⁇ Ma by asserting a level for P RX m! ⁇ that is sufficiently smaller than P RX ⁇ .
- Figure 13 shows two station pairs, (TI, Rl) and (T2, R2) communicating with each other.
- Path gains G ⁇ , G l2 , G 21 , G 22 indicating the path gain between TI and Rl, TI and R2, T2 and Rl, and T2 and R2, are shown.
- the ring 1302 indicates the transmission range of the station or node TI
- the ring 1304 indicates the transmission range of the station or node T2.
- the station T2 and the station R2 would not normally be able to transmit as station TI and station Rl are already using the medium. However if the TP for the station pairs can fulfil the conditions
- C/I is the interference ratio
- P is the transmit power
- G is the channel gain
- y mia is the minimum required C/I ratio for likely reception
- the station T2 may send a frame (e.g. RTS or DATA) provided that following condition is fulfilled,
- a frame e.g. RTS or DATA
- the frame is however only likely to be received at station R2 provided
- station T2 and station R2 must ensure that neither of them is interfering with any of station TI or station Rl .
- a failure of response from station R2 may be due to interference from either station TI or station Rl. In such case the transmission is deferred until the channel becomes free according to traditional rules defined in the IEEE 802.11-1999 standard.
- RTS Real-Time Transport Stream
- CTS CTS
- P RX max Duration
- employed LA(RTS) may be increased in the extent that P TX (RTS) can be allowed to increase.
- a procedure is now provided for determining 1 ⁇ . This procedure can be used, for example, in the Tier 3 Closed Loop DATA TPC, DATA LA and Joint TPC and LA for DATA scheme described further above. The determined value of 1 ⁇ can also be used when determined P RX ⁇ that can be subsequently transmitted in at least one of the following: a) tier 1 frames; b) tier 2 frames; or c) tier 3 frames.
- the receiving station R determines preferably the instantaneous carrier to Interference ratio CIR.
- the interference is not just determined based on measured RSSI (Received Signal Strength Indicator), but is also determined based on DURATION information that has been derived from overheard traffic between other STAs. In this manner, the expected 1 ⁇ at the start of the DATA reception can be determined.
- Figure 14 shows an interference profile at a receiving station R, and timing of the RTS and DATA signals from a Source, relative to the CTS signal from the destination (the receiving station R).
- a period DIFS occurs before the RTS signal is sent, and a SIFS separates the RTS from the CTS in time, and a SIFS also separates the CTS from the DATA in time.
- the interference profile at the destination indicates that interference is measured on overheard frames with duration information.
- the interference increases before the DIFS period begins, and then decreases to a lower level after the CTS, before the DATA transmission.
- 1 ⁇ may additionally also be filtered to better reflect a long time average interference level.
- a procedure is also provided to determine minimum required receive power.
- the minimum required receive power, P RX ⁇ is used for group TPC of RTS and CTS frames such that they can reach every intended station, even stations that experience different interference or have different noise floors.
- This information is normally distributed in IE elements, for example those defined in Figures 12 and 19-23.
- frames e.g. CTS
- P R ⁇ _ max as discussed in further above, that information will provide additional input to determine P ⁇ n ⁇ in through the relation
- the path gain is used as the cost in calculating the shortest path to the destination.
- the shortest path is the path with the minimum required TP as well as generating minimum interference. In determining the shortest path cost, the path gain to neighboring STAs need to be acquired.
- Topology control is a well-known technique for maintaining sufficient and sensible connectivity in a multihop network when TPC is employed.
- exemplary embodiments of the invention support the case having asymmetrical link(s). This may be due to a number of reasons, including for example the following reasons. Communication in each direction takes place over a non-reciprocal but short term stationary channel, e.g. FDD (Frequency Division Duplex). Stations have different TP and LA capabilities. The interference situation is different at the two communicating
- the symmetrical cases are automatically handled, as they are degenerated cases of the more asymmetric cases.
- This scenario addresses the closed loop TPC and LA for, DATA, an optional successive ACK and optional support of multiple fragments of DATA.
- the fields are the same as those defined in the IEEE 802.11-1999 standard.
- the CTS, DATA and MANAGEMENT In each of the CTS, DATA and MANAGEMENT, and
- ACK frames a new field of one octet or byte is provided, for example between the RA and FCS (Frame Check Sequence) fields in the CTS frame.
- This new field is mandatory in the CTS frame, but is optional in the other frames.
- the new field can include a) Closed Loop (CL) TPC, or b) CL LA, or c) CL joint TPC and LA.
- the field can include a P ⁇ x Request.
- Figure 24 shows an exemplary format of the P ⁇ x Request, including a reserved section of bits B0-B1 and a data section of bits B2-B7 including CL-TPC info in 1 dB steps.
- the new field is used if the ACK frame(s) is(are) adjusted.
- the new field is used if the successive DATA frame(s) is(are) adjusted.
- the frame format is as depicted in Figure 16.
- a new field of one octet or byte is provided between the Transmit Address (TA) and FCS fields, and the Receive Address (RA) and FCS fields respectively.
- the new field (relative the IEEE 802.11-1999 standard) is a P ⁇ x -P R ⁇ _ max field that includes only P ⁇ x , or P ⁇ x and P RX max combined. This new field may be mandatory in the RTS and CTS frames, but is optional in the DATA and MANAGEMENT frame and the ACK frame.
- the new field is used at least if successive DATA fragments will be sent.
- FIG. 17 The generic frame format defined in the IEEE 802.11-1999 standard is depicted in Figure 17.
- exemplary embodiments of the present invention convey numerous advantages.
- the proposed mechanisms, protocols and frame structures allow advanced and precise RRM (Radio Resource
- TPC and LA under topologies like IBSS, BSS and entirely distributed networks.
- both the TPC and the LA mechanism are to large extent instantaneous thanks to conveying TPC and LA information in RTS and CTS frames, (and optionally in DATA and ACK frames).
- a very tight instantaneous TPC and LA reduces the generated interference to a bare minimum.
- a very tight instantaneous TPC and LA reduces the power consumption to a bare minimum.
- the invention supports asymmetrical links.
- the invention supports group based TPC for RTS and CTS frames and hence reduces the generated interference as well as power consumption related to those messages to a bare minimum.
- the invention reuse the Beacon and Target Beacon Transmission Time, TBTT for measuring path gains, thereby complying well with power saving objectives as well as being power consumption efficient.
- An increased spatial reuse is attained through conditioning the channel access to being allowed as long as ongoing communication is not disturbed noticeable.
- a tiered TPC approach with few occasional high TP transmissions guiding many regular low power TP transmissions reduces the generated interference, reduces the power consumption and to a bare minimum whereas system capacity is potentially enhanced.
- Multihop based networks can take additional advantage of the distributed TP information in e.g.
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Quality & Reliability (AREA)
- Mobile Radio Communication Systems (AREA)
- Radio Relay Systems (AREA)
- Small-Scale Networks (AREA)
- Time-Division Multiplex Systems (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CNB028079698A CN1327635C (en) | 2001-04-09 | 2002-04-09 | Instantaneeous joint transmit power control and link adaptation for RTS/CTS based channel access |
AU2002253744A AU2002253744A1 (en) | 2001-04-09 | 2002-04-09 | Instantaneous joint transmit power control and link adaptation for rts/cts based channel access |
EP02723005A EP1386419B1 (en) | 2001-04-09 | 2002-04-09 | Instantaneous joint transmit power control and link adaptation for rts/cts based channel access |
DE60213583T DE60213583T2 (en) | 2001-04-09 | 2002-04-09 | MOMENTARY COMMON TRANSMISSION CONTROL AND CONNECTION ADAPTATION FOR RTS / CTS BASED CHANNEL ACCESS |
JP2002580582A JP2004533158A (en) | 2001-04-09 | 2002-04-09 | Instantaneous integrated transmit power control and link adaptation for RTS / CTS based channel access |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US28219101P | 2001-04-09 | 2001-04-09 | |
US60/282,191 | 2001-04-09 | ||
US10/117,128 | 2002-04-08 | ||
US10/117,128 US20020172186A1 (en) | 2001-04-09 | 2002-04-08 | Instantaneous joint transmit power control and link adaptation for RTS/CTS based channel access |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2002082751A2 true WO2002082751A2 (en) | 2002-10-17 |
WO2002082751A3 WO2002082751A3 (en) | 2003-11-27 |
Family
ID=26814949
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/SE2002/000706 WO2002082751A2 (en) | 2001-04-09 | 2002-04-09 | Instantaneous joint transmit power control and link adaptation for rts/cts based channel access |
Country Status (9)
Country | Link |
---|---|
US (3) | US20020172186A1 (en) |
EP (1) | EP1386419B1 (en) |
JP (1) | JP2004533158A (en) |
CN (1) | CN1327635C (en) |
AT (1) | ATE335316T1 (en) |
AU (1) | AU2002253744A1 (en) |
DE (1) | DE60213583T2 (en) |
ES (1) | ES2269676T3 (en) |
WO (1) | WO2002082751A2 (en) |
Cited By (57)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004100480A1 (en) * | 2003-05-12 | 2004-11-18 | Siemens Aktiengesellschaft | Signaling for bit allocation in a wireless lan |
WO2004088886A3 (en) * | 2003-03-26 | 2005-01-20 | Conexant Systems Inc | Mechanism for reserving multiple channels in a wireless lan |
WO2005029788A1 (en) * | 2003-09-23 | 2005-03-31 | British Telecommunications Public Limited Company | Decentralized channel selection in a self-organizing adhoc network |
WO2005041487A1 (en) | 2003-10-24 | 2005-05-06 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
WO2006035070A1 (en) * | 2004-09-30 | 2006-04-06 | Siemens Aktiengesellschaft | Method for realizing a link adaptation in a mimo-ofdm transmission system |
JP2006279951A (en) * | 2005-03-28 | 2006-10-12 | Microsoft Corp | Neighbor location discovery with directional antennas in mesh network |
JP2007509549A (en) * | 2003-10-24 | 2007-04-12 | インターナショナル・ユニヴァーシティ・ブレーメン・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツング | Inter-cell interference mitigation technology using reservation indicator |
WO2007056081A1 (en) * | 2005-11-07 | 2007-05-18 | Thomson Licensing | Apparatus and method for transmit power control frequency selection in wireless networks |
JP2007513550A (en) * | 2003-12-01 | 2007-05-24 | インターデイジタル テクノロジー コーポレーション | Wireless communication method and apparatus for implementing access point activation process and initial channel selection process |
EP1848122A1 (en) * | 2005-02-09 | 2007-10-24 | Mitsubishi Electric Corporation | Radio device and interference avoiding method by transmission power control |
JP2008048440A (en) * | 2003-07-16 | 2008-02-28 | Interdigital Technol Corp | Method for storing mobile station physical measurements and mac performance statistics in management information base of access point |
WO2009009453A2 (en) | 2007-07-10 | 2009-01-15 | Qualcomm Incorporated | Method and apparatus for power scaling in peer-to-peer communications |
EP2045930A1 (en) * | 2007-09-28 | 2009-04-08 | NTT DoCoMo, Inc. | Decentralized C/I power control for TDD |
US7580383B2 (en) * | 2002-03-28 | 2009-08-25 | Gigaset Communications Gmbh | Adaptive modulation and other extensions of the physical layer in multiple access systems |
KR100930136B1 (en) * | 2003-10-15 | 2009-12-07 | 콸콤 인코포레이티드 | High speed media access control |
US7818018B2 (en) | 2004-01-29 | 2010-10-19 | Qualcomm Incorporated | Distributed hierarchical scheduling in an AD hoc network |
US7839202B2 (en) | 2007-10-02 | 2010-11-23 | Qualcomm, Incorporated | Bandgap reference circuit with reduced power consumption |
US7882412B2 (en) | 2004-10-05 | 2011-02-01 | Sanjiv Nanda | Enhanced block acknowledgement |
EP2357867A1 (en) * | 2004-10-20 | 2011-08-17 | Kabushiki Kaisha Toshiba | Terminal transmit power control with link adaptation |
US8036676B2 (en) | 2005-02-14 | 2011-10-11 | Mitsubishi Electric Corporation | Frequency sharing method, receiving station and transmitting station |
US8098680B2 (en) | 2007-08-14 | 2012-01-17 | Motorola Mobility, Inc. | Method and system for managing transmissions in a wireless communication network |
WO2012112807A1 (en) * | 2011-02-16 | 2012-08-23 | Qualcomm Incorporated | Managing transmit power and modulation and coding scheme selection during random access in tv white space |
US8310996B2 (en) | 2006-08-07 | 2012-11-13 | Qualcomm Incorporated | Conditional scheduling for asynchronous wireless communication |
US8315271B2 (en) | 2004-03-26 | 2012-11-20 | Qualcomm Incorporated | Method and apparatus for an ad-hoc wireless communications system |
US8340027B2 (en) | 2006-08-07 | 2012-12-25 | Qualcomm Incorporated | Monitor period for asynchronous wireless communication |
WO2012112801A3 (en) * | 2011-02-16 | 2012-12-27 | Qualcomm Incorporated | Managing transmit power for better frequency re-use in tv white space |
US8355372B2 (en) | 2004-05-07 | 2013-01-15 | Qualcomm Incorporated | Transmission mode and rate selection for a wireless communication system |
US8401018B2 (en) | 2004-06-02 | 2013-03-19 | Qualcomm Incorporated | Method and apparatus for scheduling in a wireless network |
US8416762B2 (en) | 2006-08-07 | 2013-04-09 | Qualcomm Incorporated | Message exchange scheme for asynchronous wireless communication |
EP2026474A3 (en) * | 2007-08-14 | 2013-08-21 | Canon Kabushiki Kaisha | Communication apparatus and communication control method for transmission power control |
US8526410B2 (en) | 2007-07-06 | 2013-09-03 | Qualcomm Incorporated | Methods and apparatus related to interference management when sharing downlink bandwidth between wide area network usage and peer to peer signaling |
EP2635077A3 (en) * | 2008-06-16 | 2013-09-11 | Marvell World Trade Ltd. | Short-range wireless communication |
US8583159B2 (en) | 2009-10-08 | 2013-11-12 | Qualcomm Incorporated | Methods and apparatus for scaling transmit power of signals in wireless communications |
US8588705B1 (en) | 2007-12-11 | 2013-11-19 | Marvell International Ltd. | System and method of determining Power over Ethernet impairment |
US8681810B2 (en) | 2006-04-13 | 2014-03-25 | Qualcomm Incorporated | Dynamic carrier sensing thresholds |
US8730841B2 (en) | 2007-07-06 | 2014-05-20 | Qualcomm Incorporated | Peer to peer communications methods and apparatus providing for use of both WAN uplink and downlink bands |
US8737313B2 (en) | 2006-08-07 | 2014-05-27 | Qualcomm Incorporated | Transmit time segments for asynchronous wireless communication |
US8774098B2 (en) | 2003-10-15 | 2014-07-08 | Qualcomm Incorporated | Method, apparatus, and system for multiplexing protocol data units |
US8903440B2 (en) | 2004-01-29 | 2014-12-02 | Qualcomm Incorporated | Distributed hierarchical scheduling in an ad hoc network |
US8923788B1 (en) | 2008-06-27 | 2014-12-30 | Marvell International Ltd. | Circuit and method for adjusting a digitally controlled oscillator |
US8934353B2 (en) | 2009-10-08 | 2015-01-13 | Qualcomm Incorporated | Methods and apparatus for scaling transmit power of signals in wireless communications |
US8983557B1 (en) | 2011-06-30 | 2015-03-17 | Marvell International Ltd. | Reducing power consumption of a multi-antenna transceiver |
US8982826B1 (en) | 2009-04-24 | 2015-03-17 | Marvell International Ltd. | Method for transmitting information in a regulated spectrum and network configured to operate in the regulated spectrum |
US9008002B2 (en) | 2006-08-07 | 2015-04-14 | Qualcomm Incorporated | Conditional requests for asynchronous wireless communication |
US9031044B2 (en) | 2008-08-20 | 2015-05-12 | Qualcomm Incorporated | Power control for wireless LAN stations |
US9055460B1 (en) | 2008-08-11 | 2015-06-09 | Marvell International Ltd. | Location-based detection of interference in cellular communications systems |
US9066369B1 (en) | 2009-09-16 | 2015-06-23 | Marvell International Ltd. | Coexisting radio communication |
US9072101B2 (en) | 2003-10-15 | 2015-06-30 | Qualcomm Incorporated | High speed media access control and direct link protocol |
US9078108B1 (en) | 2011-05-26 | 2015-07-07 | Marvell International Ltd. | Method and apparatus for off-channel invitation |
US9198194B2 (en) | 2005-09-12 | 2015-11-24 | Qualcomm Incorporated | Scheduling with reverse direction grant in wireless communication systems |
US9226308B2 (en) | 2003-10-15 | 2015-12-29 | Qualcomm Incorporated | Method, apparatus, and system for medium access control |
WO2016010675A1 (en) * | 2014-07-18 | 2016-01-21 | Intel Corporation | Mac protocol for full duplex wireless communications |
EP3070980A4 (en) * | 2013-11-15 | 2016-11-16 | Huawei Tech Co Ltd | Power adjustment method and apparatus |
US9585025B2 (en) | 2011-02-16 | 2017-02-28 | Qualcomm Incorporated | Managing transmit power for better frequency re-use in TV white space |
US9655041B1 (en) | 2008-12-31 | 2017-05-16 | Marvell International Ltd. | Discovery-phase power conservation |
EP3534665A1 (en) * | 2018-03-01 | 2019-09-04 | Apple Inc. | Request to send (rts)/clear to send (cts) design in 5g |
US11265787B2 (en) | 2003-02-24 | 2022-03-01 | Intellectual Ventures Ii Llc | Program for adjusting channel interference between access points in a wireless network |
Families Citing this family (165)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2002037754A2 (en) | 2000-11-03 | 2002-05-10 | At & T Corp. | Tiered contention multiple access (tcma): a method for priority-based shared channel access |
WO2002071650A1 (en) * | 2001-03-02 | 2002-09-12 | At & T Corp. | Interference suppression methods for 802.11 |
US7136361B2 (en) | 2001-07-05 | 2006-11-14 | At&T Corp. | Hybrid coordination function (HCF) access through tiered contention and overlapped wireless cell mitigation |
US7277413B2 (en) | 2001-07-05 | 2007-10-02 | At & T Corp. | Hybrid coordination function (HCF) access through tiered contention and overlapped wireless cell mitigation |
US7245592B2 (en) * | 2001-07-09 | 2007-07-17 | Koninklijke Philips Electronics N.V. | Aligning 802.11e HCF and 802.11h TPC operations |
DE10142496A1 (en) * | 2001-08-30 | 2003-03-27 | Siemens Ag | Connection set-up involves searching for transmitter/receiver in radio range of initialized transmission power value, comparing transmission power values, ending search or repeating |
ES2292847T3 (en) * | 2001-09-27 | 2008-03-16 | Telefonaktiebolaget Lm Ericsson (Publ) | RUNNING METHOD FOR MULTIPLE JUMPS FOR DISTRIBUTED WLAN NETWORKS. |
US7248600B2 (en) | 2001-11-02 | 2007-07-24 | At&T Corp. | ‘Shield’: protecting high priority channel access attempts in overlapped wireless cells |
US7277415B2 (en) * | 2001-11-02 | 2007-10-02 | At&T Corp. | Staggered startup for cyclic prioritized multiple access (CPMA) contention-free sessions |
US7280517B2 (en) * | 2001-11-02 | 2007-10-09 | At&T Corp. | Wireless LANs and neighborhood capture |
US7180905B2 (en) * | 2001-11-02 | 2007-02-20 | At & T Corp. | Access method for periodic contention-free sessions |
US7245605B2 (en) | 2001-11-02 | 2007-07-17 | At&T Corp. | Preemptive packet for maintaining contiguity in cyclic prioritized multiple access (CPMA) contention-free sessions |
US7245604B2 (en) | 2001-11-02 | 2007-07-17 | At&T Corp. | Fixed deterministic post-backoff for cyclic prioritized multiple access (CPMA) contention-free sessions |
EP1335537A1 (en) * | 2002-02-01 | 2003-08-13 | Thomson Licensing S.A. | Method for evaluating radio links in a communication network |
EP1335536A1 (en) * | 2002-02-01 | 2003-08-13 | Thomson Licensing S.A. | Method for radio link adaptation in a network with contention-based medium access |
US6785520B2 (en) | 2002-03-01 | 2004-08-31 | Cognio, Inc. | System and method for antenna diversity using equal power joint maximal ratio combining |
US6862456B2 (en) * | 2002-03-01 | 2005-03-01 | Cognio, Inc. | Systems and methods for improving range for multicast wireless communication |
US6871049B2 (en) | 2002-03-21 | 2005-03-22 | Cognio, Inc. | Improving the efficiency of power amplifiers in devices using transmit beamforming |
US7742443B2 (en) * | 2002-05-28 | 2010-06-22 | Maarten Menzo Wentink | Transmit power management in shared-communications channel networks |
US7948951B2 (en) * | 2002-06-12 | 2011-05-24 | Xocyst Transfer Ag L.L.C. | Automatic peer discovery |
USRE43127E1 (en) | 2002-06-12 | 2012-01-24 | Intellectual Ventures I Llc | Event-based multichannel direct link |
US8050360B2 (en) | 2002-06-12 | 2011-11-01 | Intellectual Ventures I Llc | Direct link relay in a wireless network |
US7251235B2 (en) * | 2002-06-12 | 2007-07-31 | Conexant, Inc. | Event-based multichannel direct link |
US7933293B2 (en) * | 2002-06-12 | 2011-04-26 | Xocyst Transfer Ag L.L.C. | Link margin notification using return frame |
US8787988B2 (en) * | 2003-01-29 | 2014-07-22 | Intellectual Ventures I Llc | Power management for wireless direct link |
US7738848B2 (en) * | 2003-01-14 | 2010-06-15 | Interdigital Technology Corporation | Received signal to noise indicator |
US20040235423A1 (en) * | 2003-01-14 | 2004-11-25 | Interdigital Technology Corporation | Method and apparatus for network management using perceived signal to noise and interference indicator |
US7545771B2 (en) * | 2003-01-29 | 2009-06-09 | Xocyst Transfer Ag L.L.C. | Independent direct link protocol |
EP1592175A4 (en) * | 2003-02-03 | 2010-03-17 | Sony Corp | Communication method, communication device, and computer program |
US7215928B2 (en) * | 2003-05-02 | 2007-05-08 | Nortel Networks Limited | Path selection in wireless networks |
US7869822B2 (en) | 2003-02-24 | 2011-01-11 | Autocell Laboratories, Inc. | Wireless network apparatus and system field of the invention |
KR20050105259A (en) * | 2003-02-27 | 2005-11-03 | 코닌클리즈케 필립스 일렉트로닉스 엔.브이. | Apparatus and method to optimize power management in an independent basis service set of a wireless local area network |
US7801092B2 (en) * | 2003-03-21 | 2010-09-21 | Cisco Technology, Inc. | Method for a simple 802.11e HCF implementation |
JP3922571B2 (en) * | 2003-03-26 | 2007-05-30 | ソニー株式会社 | Information processing apparatus, information processing method, recording medium, and program |
KR101142556B1 (en) | 2003-05-14 | 2012-05-03 | 인터디지탈 테크날러지 코포레이션 | Network management using periodic measurements of indicators |
US7397785B2 (en) | 2003-05-28 | 2008-07-08 | Nokia Corporation | Method for enhancing fairness and performance in a multihop ad hoc network and corresponding system |
US7075890B2 (en) * | 2003-06-06 | 2006-07-11 | Meshnetworks, Inc. | System and method to provide fairness and service differentation in ad-hoc networks |
JP4505454B2 (en) * | 2003-06-06 | 2010-07-21 | メッシュネットワークス インコーポレイテッド | System and method for improving overall performance of a wireless communication network |
ES2221803B1 (en) * | 2003-06-18 | 2006-03-01 | Diseño De Sistemas En Silicio, S.A. | PROCEDURE FOR ACCESS TO THE MEDIA TRANSMISSION OF MULTIPLE NODES OF COMMUNICATIONS ON ELECTRICAL NETWORK. |
MXPA06000603A (en) | 2003-07-16 | 2006-04-11 | Interdigital Tech Corp | Method and system for transferring information between network management entities of a wireless communication system. |
US20050128977A1 (en) * | 2003-07-23 | 2005-06-16 | Interdigital Technology Corporation | Method and apparatus for determining and managing congestion in a wireless communications system |
US8005055B2 (en) | 2003-07-23 | 2011-08-23 | Interdigital Technology Corporation | Method and apparatus for determining and managing congestion in a wireless communications system |
EP1650901B1 (en) * | 2003-07-29 | 2019-02-27 | Sony Corporation | Radio communication system, radio communication device, radio communication method, and computer program |
US7065144B2 (en) | 2003-08-27 | 2006-06-20 | Qualcomm Incorporated | Frequency-independent spatial processing for wideband MISO and MIMO systems |
CN1592245A (en) * | 2003-09-02 | 2005-03-09 | 皇家飞利浦电子股份有限公司 | Power controlling method and apparatus for use in WLAN |
US8472473B2 (en) | 2003-10-15 | 2013-06-25 | Qualcomm Incorporated | Wireless LAN protocol stack |
US8842657B2 (en) | 2003-10-15 | 2014-09-23 | Qualcomm Incorporated | High speed media access control with legacy system interoperability |
US8284752B2 (en) | 2003-10-15 | 2012-10-09 | Qualcomm Incorporated | Method, apparatus, and system for medium access control |
US8274961B2 (en) | 2003-10-24 | 2012-09-25 | Sony Corporation | Apparatus and associated methodology of adjusting a RTS/CTS transmission protocol |
JP2006050519A (en) * | 2003-10-24 | 2006-02-16 | Sony Corp | Wireless communications system, wireless communications apparatus, wireless communication method, and computer program |
WO2005046134A1 (en) | 2003-10-31 | 2005-05-19 | Conexant Inc. | Link margin notification using return frame |
US20050157674A1 (en) * | 2003-10-31 | 2005-07-21 | Globespanvirata Incorporated | Time-scheduled multichannel direct link |
JP4286109B2 (en) * | 2003-11-04 | 2009-06-24 | 株式会社あまの創健 | Oil-containing fat wastewater treatment equipment for grease trap and grease trap |
US20050094558A1 (en) * | 2003-11-05 | 2005-05-05 | Interdigital Technology Corporation | Wireless local area network (WLAN) methods and components that utilize traffic prediction |
EP1530316A1 (en) * | 2003-11-10 | 2005-05-11 | Go Networks | Improving the performance of a wireless packet data communication system |
EP1542418A1 (en) * | 2003-12-10 | 2005-06-15 | Telefonaktiebolaget LM Ericsson (publ) | Wireless multicarrier system with subcarriers reserved for communication between unsynchronized nodes |
US7809394B1 (en) * | 2003-12-17 | 2010-10-05 | Intel Corporation | Transmit power control in a wireless system |
JP4710321B2 (en) * | 2004-02-02 | 2011-06-29 | ソニー株式会社 | Wireless communication system, wireless communication apparatus, wireless communication method, and computer program |
JP2007533173A (en) * | 2004-02-02 | 2007-11-15 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | An improved network allocation vector mechanism for optimal reuse of frequency bands in wireless communication systems |
US7545827B2 (en) * | 2004-02-13 | 2009-06-09 | Hong Kong Applied Science And Technology Research Institute Co., Ltd. | Busy tone for wireless networks |
US8175016B1 (en) * | 2004-03-19 | 2012-05-08 | Verizon Corporate Services Group Inc. | Systems, methods and computer readable media for energy conservation in sensor networks |
US7826431B2 (en) * | 2004-05-14 | 2010-11-02 | Interdigital Technology Corporation | Method of selectively adjusting the configuration of an access point antenna to enhance mobile station coverage |
KR100837710B1 (en) * | 2004-05-14 | 2008-06-16 | 인터디지탈 테크날러지 코포레이션 | Method of selectively adjusting the configuration of an access point antenna to enhance mobile station coverage |
EP1749377A1 (en) * | 2004-05-24 | 2007-02-07 | NTT DoCoMo, Inc. | Virtual channel reservation control |
US20060002428A1 (en) * | 2004-06-30 | 2006-01-05 | Trainin Solomon B | System, method and device for wireless transmission |
US7773535B2 (en) * | 2004-08-12 | 2010-08-10 | Motorola, Inc. | Method and apparatus for closed loop transmission |
US20060045022A1 (en) * | 2004-08-31 | 2006-03-02 | Jarkko Kneckt | Apparatus, and associated method, for generating packet acknowledgment replies during operation of a packet communication system |
TWI375418B (en) | 2004-10-20 | 2012-10-21 | Koninkl Philips Electronics Nv | A system and method for dynamic adaptation of data rate and transmit power with a beaconing protocol |
WO2006046201A1 (en) | 2004-10-29 | 2006-05-04 | Philips Intellectual Property & Standards Gmbh | A method of operating a network node of a network, a network node, a network system, a computer-readable medium, and a program element |
US7855986B2 (en) * | 2004-11-26 | 2010-12-21 | Panasonic Corporation | Communication terminal and method for handling power off time |
JP4736434B2 (en) * | 2005-01-11 | 2011-07-27 | ソニー株式会社 | Data transmission system |
US7768988B2 (en) * | 2005-02-22 | 2010-08-03 | Intel Corporation | Method and apparatus to perform network medium reservation in a wireless network |
US8830846B2 (en) * | 2005-04-04 | 2014-09-09 | Interdigital Technology Corporation | Method and system for improving responsiveness in exchanging frames in a wireless local area network |
JP4747646B2 (en) * | 2005-04-11 | 2011-08-17 | ソニー株式会社 | Wireless communication system, wireless communication device, wireless communication method, and computer program. |
TWM298284U (en) * | 2005-04-21 | 2006-09-21 | Interdigital Tech Corp | Wireless local area network for signaling deferral management messages |
US8184655B2 (en) * | 2005-04-21 | 2012-05-22 | Interdigital Technology Corporation | Wireless communication method and WLAN for signaling deferral management messages |
US7577438B2 (en) | 2005-04-25 | 2009-08-18 | Interdigital Technology Corporation | Method and system for efficient addressing and power savings in wireless systems |
US7822009B2 (en) * | 2005-05-09 | 2010-10-26 | Industrial Technology Research Institute | Distributed medium access protocol for wireless mesh networks |
KR20080016943A (en) * | 2005-06-08 | 2008-02-22 | 아바야 테크놀러지 코퍼레이션 | Avoding exposed node problems in wireless local area networks |
US7406327B2 (en) * | 2005-06-09 | 2008-07-29 | Harris Corporation | System that adapts power for minimizing the total amount of transmitted power within a wireless communications network and related method |
US8068507B2 (en) * | 2005-06-14 | 2011-11-29 | Interdigital Technology Corporation | Method and system for conveying backhaul link information for intelligent selection of a mesh access point |
JP4604916B2 (en) * | 2005-08-29 | 2011-01-05 | パナソニック株式会社 | Wireless network system, wireless communication method, and wireless communication apparatus |
DE102005047753B4 (en) * | 2005-09-28 | 2007-10-11 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Signaling method for decentralized online transmission power allocation in a wireless network |
WO2007043925A1 (en) * | 2005-10-14 | 2007-04-19 | Telefonaktiebolaget Lm Ericsson (Publ) | Method for power control in a wireless station |
US20070087693A1 (en) * | 2005-10-17 | 2007-04-19 | David Johnston | Common announcement signaling format |
US8576872B2 (en) * | 2005-10-19 | 2013-11-05 | Qualcomm Incorporated | Multi-hop wireless mesh network medium access control protocol |
US8483616B1 (en) * | 2005-11-01 | 2013-07-09 | At&T Intellectual Property Ii, L.P. | Non-interference technique for spatially aware mobile ad hoc networking |
US8411616B2 (en) | 2005-11-03 | 2013-04-02 | Piccata Fund Limited Liability Company | Pre-scan for wireless channel selection |
US20070097903A1 (en) * | 2005-11-03 | 2007-05-03 | Interdigital Technology Corporation | Method and apparatus of exchanging messages via a wireless distribution system between groups operating in different frequencies |
EP1946472B1 (en) * | 2005-11-07 | 2017-03-01 | Telefonaktiebolaget LM Ericsson (publ) | Implicit signaling for link adaptation |
US8068428B2 (en) * | 2005-11-09 | 2011-11-29 | Meshnetworks, Inc. | System and method for performing topology control in a wireless network |
KR101246774B1 (en) * | 2005-11-22 | 2013-03-26 | 삼성전자주식회사 | Method and apparatus for transmitting/receiving a signal in a wireless local network mesh communication system |
EP1958394A2 (en) | 2005-12-02 | 2008-08-20 | Koninklijke Philips Electronics N.V. | Wireless systems and methods including cooperative communication medium access control |
US8412249B2 (en) * | 2005-12-20 | 2013-04-02 | Alcatel Lucent | Resource allocation based on interference mitigation in a wireless communication system |
JP4542997B2 (en) * | 2006-02-08 | 2010-09-15 | 株式会社東芝 | Wireless communication apparatus and wireless communication method |
DE102006014308A1 (en) * | 2006-03-10 | 2007-09-13 | Rohde & Schwarz Gmbh & Co. Kg | Method for multi-hop data transmission in an ad hoc network with hidden nodes |
US9419816B2 (en) * | 2008-08-04 | 2016-08-16 | General Electric Company | System, method, and computer software code for providing an auxiliary communication path when a primary communication path is unavailable |
EP1855423B1 (en) * | 2006-05-12 | 2013-12-18 | NTT DoCoMo, Inc. | Decentralized multi-user link adaptation for QoS support |
EP1855422B1 (en) * | 2006-05-12 | 2009-12-02 | NTT DoCoMo, Inc. | Receiver feedback and broadcast signaling using busy bursts |
EP1855390B1 (en) * | 2006-05-12 | 2008-05-07 | NTT DoCoMo, Inc. | Methods and devices for interference tolerance signalling and power control using busy-signal concept |
US7787410B2 (en) * | 2006-05-30 | 2010-08-31 | Intel Corporation | Communication within a wireless network using multiple signal transmission powers |
US8046019B2 (en) * | 2006-08-04 | 2011-10-25 | Futurewei Technologies, Inc. | Method and system for optimal allocation of uplink transmission power in communication networks |
CN105025586B (en) * | 2006-08-07 | 2018-12-11 | 高通股份有限公司 | Conditional request for asynchronous wireless communication |
US8126205B2 (en) * | 2006-09-25 | 2012-02-28 | Cambridge Research & Instrumentation, Inc. | Sample imaging and classification |
US7890072B2 (en) * | 2006-09-27 | 2011-02-15 | Silicon Laboratories, Inc. | Wireless communication apparatus for estimating(C/I) ratio using a variable bandwidth filter |
US8774140B2 (en) * | 2006-10-19 | 2014-07-08 | Intel Corporation | Method and apparatus to provide hidden node protection |
US20100039969A1 (en) * | 2006-11-16 | 2010-02-18 | Nec Corporation | Radio communication device, radio communication method, and radio communication program |
US8879448B2 (en) * | 2006-12-22 | 2014-11-04 | Samsung Electronics Co., Ltd. | Apparatus for controlling power of WiMedia media access control device and method using the same |
US8325654B2 (en) * | 2006-12-28 | 2012-12-04 | Futurewei Technologies, Inc. | Integrated scheduling and power control for the uplink of an OFDMA network |
US7983230B1 (en) * | 2007-07-11 | 2011-07-19 | Itt Manufacturing Enterprises, Inc. | Adaptive power and data rate control for ad-hoc mobile wireless systems |
US20090036144A1 (en) * | 2007-07-31 | 2009-02-05 | Wong Wendy C | Techniques for mobility induced error correction |
US8369782B1 (en) | 2007-08-13 | 2013-02-05 | Marvell International Ltd. | Bluetooth wideband scan mode |
US8577305B1 (en) | 2007-09-21 | 2013-11-05 | Marvell International Ltd. | Circuits and methods for generating oscillating signals |
CN101188446B (en) * | 2007-12-05 | 2012-04-04 | 华为技术有限公司 | Power control method and device |
CN101465797B (en) * | 2007-12-17 | 2011-07-06 | 华为技术有限公司 | Data transmission method, system, sending terminal node and receiving terminal node |
WO2009093537A1 (en) * | 2008-01-25 | 2009-07-30 | Nippon Chemical Works Co., Ltd. | Fluorescent agent having ethynyl group |
FR2928479B1 (en) * | 2008-03-05 | 2011-07-01 | Somfy Sas | METHOD OF COMMUNICATING BETWEEN A FIRST NODE AND A SECOND NODE OF A DOMOTIC INSTALLATION |
US20090274226A1 (en) * | 2008-05-05 | 2009-11-05 | Motorola, Inc. | Sounding channel based feedback in a wireless communication system |
TW200950410A (en) * | 2008-05-21 | 2009-12-01 | Realtek Semiconductor Corp | Channel utilizing method and system for wireless network |
CN101345579B (en) * | 2008-06-18 | 2012-05-23 | 西北工业大学 | Multi-access method based on combination of channel perception and channel reservation |
EP2184880A1 (en) * | 2008-11-07 | 2010-05-12 | Thomson Licensing | A method of data rate adaptation for multicast communication |
EP2890190B8 (en) * | 2009-02-03 | 2019-12-25 | Sharp Kabushiki Kaisha | Wireless communication system, base station apparatus, mobile station apparatus, and communication method |
PL387490A1 (en) * | 2009-03-13 | 2010-09-27 | Akademia Górniczo-Hutnicza im. Stanisława Staszica | Method of access control for the devices to the communication link in the dispersed networks |
US8472427B1 (en) | 2009-04-06 | 2013-06-25 | Marvell International Ltd. | Packet exchange arbitration for coexisting radios |
TWI466564B (en) * | 2009-07-16 | 2014-12-21 | Realtek Semiconductor Corp | Apparatus and method for adjusting transmission power of communication system |
US8750269B2 (en) * | 2009-10-23 | 2014-06-10 | Electronics And Telecommunications Research Institute | Method and apparatus for controlling transmission power in WLAN system |
US9118428B2 (en) | 2009-11-04 | 2015-08-25 | At&T Intellectual Property I, L.P. | Geographic advertising using a scalable wireless geocast protocol |
CN101695019B (en) * | 2009-11-10 | 2013-03-20 | 杭州华三通信技术有限公司 | Method and device for message transmission |
US8767771B1 (en) | 2010-05-11 | 2014-07-01 | Marvell International Ltd. | Wakeup beacons for mesh networks |
CN101902822B (en) * | 2010-07-22 | 2012-12-26 | 北京交通大学 | Base station-assisted mobile terminal equipment autonomously accessing method and device |
JP5520756B2 (en) * | 2010-09-07 | 2014-06-11 | 日本電信電話株式会社 | Wireless communication method and wireless communication system |
US9998571B2 (en) | 2010-10-01 | 2018-06-12 | Qualcomm Incorporated | Legacy-compatible control frames |
WO2012047198A1 (en) * | 2010-10-05 | 2012-04-12 | Utc Fire & Security Corporation | Bi-directional link margin establishment for wireless embedded systems |
EP2630827B1 (en) | 2010-10-20 | 2018-11-21 | Marvell World Trade Ltd. | Pre-association service discovery |
US20120263055A1 (en) * | 2011-03-11 | 2012-10-18 | Mediatek Singapore Pte. Ltd. | Fast Link Adaptation and Transmit Power Control in Wireless Networks |
WO2012169751A2 (en) * | 2011-06-08 | 2012-12-13 | 엘지전자 주식회사 | Method and device for transmitting a frame using a multiple physical layer in a wireless lan system |
US9319842B2 (en) | 2011-06-27 | 2016-04-19 | At&T Intellectual Property I, L.P. | Mobile device configured point and shoot type weapon |
US9161158B2 (en) | 2011-06-27 | 2015-10-13 | At&T Intellectual Property I, L.P. | Information acquisition using a scalable wireless geocast protocol |
US9125216B1 (en) | 2011-09-28 | 2015-09-01 | Marvell International Ltd. | Method and apparatus for avoiding interference among multiple radios |
WO2013069906A1 (en) * | 2011-11-07 | 2013-05-16 | 엘지전자 주식회사 | Link adaptation and device in active scanning method |
WO2013119810A1 (en) | 2012-02-07 | 2013-08-15 | Marvell World Trade Ltd. | Method and apparatus for multi-network communication |
CN103378926B (en) * | 2012-04-20 | 2018-03-27 | 北京新岸线移动多媒体技术有限公司 | Data transmission method, system and device in a kind of multi-hop link |
US9386584B2 (en) * | 2012-06-11 | 2016-07-05 | Qualcomm Incorporated | Inter-frame spacing duration for sub-1 gigahertz wireless networks |
US9450649B2 (en) | 2012-07-02 | 2016-09-20 | Marvell World Trade Ltd. | Shaping near-field transmission signals |
US9071451B2 (en) | 2012-07-31 | 2015-06-30 | At&T Intellectual Property I, L.P. | Geocast-based situation awareness |
US20150282157A1 (en) * | 2012-10-04 | 2015-10-01 | Lg Electronics Inc. | Method and device for updating system information in wireless lan system |
US9660745B2 (en) | 2012-12-12 | 2017-05-23 | At&T Intellectual Property I, L.P. | Geocast-based file transfer |
WO2014137172A1 (en) * | 2013-03-07 | 2014-09-12 | 엘지전자 주식회사 | Method and apparatus for receiving signal by station in wireless lan system |
GB2514169B (en) * | 2013-05-16 | 2016-01-13 | Broadcom Corp | Method and apparatus for scaling coverage |
US9807699B2 (en) * | 2013-09-13 | 2017-10-31 | Interdigital Patent Holdings, Inc. | Clear channel assessment (CCA) threshold adaptation method |
CN105393589B (en) * | 2013-09-29 | 2019-08-02 | 华为技术有限公司 | A kind of method and apparatus of data transmission |
US20150117366A1 (en) * | 2013-10-29 | 2015-04-30 | Qualcomm Incorporated | Systems and methods for improved communication efficiency in high efficiency wireless networks |
US9661634B2 (en) | 2013-11-01 | 2017-05-23 | Qualcomm Incorporated | Systems and methods for improved communication efficiency in high efficiency wireless networks |
WO2015187160A1 (en) | 2014-06-05 | 2015-12-10 | Intel IP Corporation | Interference management techniques for full-duplex wireless communications |
CN104602334B (en) * | 2015-02-02 | 2018-02-16 | 中山大学花都产业科技研究院 | A kind of Power Control optimization method of point-to-multipoint communication system |
US20170245305A1 (en) * | 2015-03-10 | 2017-08-24 | Kabushiki Kaisha Toshiba | Wireless Communication Methods and Apparatus |
US9872298B2 (en) * | 2015-04-16 | 2018-01-16 | Qualcomm Incorporated | System and method for reducing collisions in wireless networks |
CN106656428B (en) * | 2015-10-28 | 2020-05-22 | 中兴通讯股份有限公司 | Method and device for adjusting contention window |
US10531400B2 (en) * | 2016-03-02 | 2020-01-07 | Sony Corporation | Information processing device, communication system, information processing method, and program |
CN106454994A (en) * | 2016-10-15 | 2017-02-22 | 黄林果 | Power control technology based on dynamic logical topology |
US10425779B2 (en) * | 2016-12-16 | 2019-09-24 | Qualcomm Incorporated | Power-adaptive sidelink data transmissions |
US20190268776A1 (en) * | 2018-02-27 | 2019-08-29 | Qualcomm Incorporated | System and method for spatial reuse |
JP7140977B2 (en) * | 2019-03-15 | 2022-09-22 | 日本電信電話株式会社 | INTERFERENCE EVALUATION METHOD, INTERFERENCE EVALUATION DEVICE, AND INTERFERENCE EVALUATION PROGRAM |
CN114258028A (en) * | 2020-09-24 | 2022-03-29 | 京东方科技集团股份有限公司 | Channel allocation method and communication equipment |
CN114727372B (en) * | 2022-03-08 | 2024-04-09 | 中国科学院上海微系统与信息技术研究所 | Energy-saving SIC method based on distributed link scheduling and power control |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5732077A (en) * | 1995-11-13 | 1998-03-24 | Lucent Technologies Inc. | Resource allocation system for wireless networks |
WO1999026364A1 (en) * | 1997-11-18 | 1999-05-27 | International Business Machines Corporation | Method for improved wireless optical communication and frames for use in a wireless optical communication system |
WO1999034531A1 (en) * | 1997-12-24 | 1999-07-08 | Telefonaktiebolaget Lm Ericsson (Publ) | Initial transmit power determination in a radiocommunication system |
US5956649A (en) * | 1995-04-25 | 1999-09-21 | Lucent Technologies Inc. | Method and apparatus for power control in wireless networks |
US5982765A (en) * | 1996-02-26 | 1999-11-09 | Nec Corporation | Time division multiple access radio data communication method |
EP1001572A1 (en) * | 1998-11-12 | 2000-05-17 | Lucent Technologies Inc. | Quick assignment method for multiple access schemes |
WO2000038351A2 (en) * | 1998-12-18 | 2000-06-29 | Telefonaktiebolaget Lm Ericsson (Publ) | Method in a telecommunication system |
EP1050977A2 (en) * | 1999-05-06 | 2000-11-08 | Lucent Technologies Inc. | Power control system using acknowledgements |
WO2000076083A1 (en) * | 1999-06-02 | 2000-12-14 | Nokia Corporation | A method of controlling power |
Family Cites Families (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
AU7210894A (en) | 1993-06-25 | 1995-01-17 | Xircom, Inc. | Virtual carrier detection for wireless local area network with distributed control |
US5844905A (en) * | 1996-07-09 | 1998-12-01 | International Business Machines Corporation | Extensions to distributed MAC protocols with collision avoidance using RTS/CTS exchange |
US5893036A (en) * | 1997-01-30 | 1999-04-06 | Motorola, Inc. | Transmission power control method |
US6295285B1 (en) * | 1997-04-17 | 2001-09-25 | Lucent Technologies Inc. | Global packet dynamic resource allocation for wireless networks |
US6611521B1 (en) * | 1998-07-14 | 2003-08-26 | International Business Machines Corporation | Data link layer extensions to a high latency wireless MAC protocol |
US6498785B1 (en) * | 1998-10-02 | 2002-12-24 | Nokia Mobile Phones Ltd | Method and apparatus for power control on a common channel in a telecommunication system |
DE69925852T2 (en) * | 1998-10-30 | 2006-05-04 | Broadcom Corp., Irvine | TRANSMISSION WITH NON-FULL DATA RATES USING MULTIPLEXED CONSTELLATIONS |
US20020082019A1 (en) * | 1998-12-30 | 2002-06-27 | Oguz Sunay | Methods and apparatus for accomplishing inter-frequency, inter-network, and inter-tier soft handoff using dual transmission/reception or compression |
US20020098860A1 (en) * | 1999-01-12 | 2002-07-25 | Pecen Mark E. | Transmit power control method and apparatus |
US7136654B1 (en) * | 1999-09-20 | 2006-11-14 | Motorola, Inc. | Power based channel assignment in a wireless communication system |
US6859463B1 (en) * | 1999-11-08 | 2005-02-22 | Itt Manufacturing Enterprises, Inc. | Methods and apparatus for organizing selection of operational parameters in a communication system |
US7492248B1 (en) * | 2000-01-14 | 2009-02-17 | Symbol Technologies, Inc. | Multi-tier wireless communications architecture, applications and methods |
AU2001293346A1 (en) * | 2000-04-06 | 2001-10-23 | Rutgers, The State University Of New Jersey | Method and system for closed loop power control in wireless systems |
US6862457B1 (en) * | 2000-06-21 | 2005-03-01 | Qualcomm Incorporated | Method and apparatus for adaptive reverse link power control using mobility profiles |
US6411608B2 (en) * | 2000-07-12 | 2002-06-25 | Symbol Technologies, Inc. | Method and apparatus for variable power control in wireless communications systems |
EP1323288A4 (en) * | 2000-08-14 | 2007-03-21 | Main Net Comm Ltd | Power line communication system |
US6807165B2 (en) * | 2000-11-08 | 2004-10-19 | Meshnetworks, Inc. | Time division protocol for an ad-hoc, peer-to-peer radio network having coordinating channel access to shared parallel data channels with separate reservation channel |
US6711416B1 (en) * | 2000-11-28 | 2004-03-23 | Hongliang Zhang | Fixed wireless communication system having power control for downlink data traffic |
US6973039B2 (en) * | 2000-12-08 | 2005-12-06 | Bbnt Solutions Llc | Mechanism for performing energy-based routing in wireless networks |
US7126930B2 (en) * | 2001-02-10 | 2006-10-24 | Qualcomm, Incorporated | Method and apparatus for transmitting messages in a wireless communication system |
US6967944B2 (en) * | 2001-03-30 | 2005-11-22 | Koninklijke Philips Electronics N.V. | Increasing link capacity via concurrent transmissions in centralized wireless LANs |
US20040141522A1 (en) * | 2001-07-11 | 2004-07-22 | Yossi Texerman | Communications protocol for wireless lan harmonizing the ieee 802.11a and etsi hiperla/2 standards |
-
2002
- 2002-04-08 US US10/117,128 patent/US20020172186A1/en not_active Abandoned
- 2002-04-09 CN CNB028079698A patent/CN1327635C/en not_active Expired - Lifetime
- 2002-04-09 DE DE60213583T patent/DE60213583T2/en not_active Expired - Lifetime
- 2002-04-09 WO PCT/SE2002/000706 patent/WO2002082751A2/en active IP Right Grant
- 2002-04-09 JP JP2002580582A patent/JP2004533158A/en active Pending
- 2002-04-09 AU AU2002253744A patent/AU2002253744A1/en not_active Abandoned
- 2002-04-09 AT AT02723005T patent/ATE335316T1/en not_active IP Right Cessation
- 2002-04-09 ES ES02723005T patent/ES2269676T3/en not_active Expired - Lifetime
- 2002-04-09 EP EP02723005A patent/EP1386419B1/en not_active Expired - Lifetime
-
2007
- 2007-11-29 US US11/947,306 patent/US7885680B2/en not_active Expired - Lifetime
- 2007-11-29 US US11/947,341 patent/US20080076466A1/en not_active Abandoned
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5956649A (en) * | 1995-04-25 | 1999-09-21 | Lucent Technologies Inc. | Method and apparatus for power control in wireless networks |
US5732077A (en) * | 1995-11-13 | 1998-03-24 | Lucent Technologies Inc. | Resource allocation system for wireless networks |
US5982765A (en) * | 1996-02-26 | 1999-11-09 | Nec Corporation | Time division multiple access radio data communication method |
WO1999026364A1 (en) * | 1997-11-18 | 1999-05-27 | International Business Machines Corporation | Method for improved wireless optical communication and frames for use in a wireless optical communication system |
WO1999034531A1 (en) * | 1997-12-24 | 1999-07-08 | Telefonaktiebolaget Lm Ericsson (Publ) | Initial transmit power determination in a radiocommunication system |
EP1001572A1 (en) * | 1998-11-12 | 2000-05-17 | Lucent Technologies Inc. | Quick assignment method for multiple access schemes |
WO2000038351A2 (en) * | 1998-12-18 | 2000-06-29 | Telefonaktiebolaget Lm Ericsson (Publ) | Method in a telecommunication system |
EP1050977A2 (en) * | 1999-05-06 | 2000-11-08 | Lucent Technologies Inc. | Power control system using acknowledgements |
WO2000076083A1 (en) * | 1999-06-02 | 2000-12-14 | Nokia Corporation | A method of controlling power |
Non-Patent Citations (2)
Title |
---|
CHOW F M ET AL: "Effect Of Non-reciprocity On Infrared Wireless Local-area Networks" IEEE GLOBECOM 1999, XP010373322 * |
LAL S ET AL: "DISTRIBUTED RESOURCE ALLOCATION FOR DS-CDMA-BASED MULTIMEDIA AD HOC WIRELESS LAN'S" IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, IEEE INC. NEW YORK, US, vol. 17, no. 5, May 1999 (1999-05), pages 947-967, XP000830247 ISSN: 0733-8716 * |
Cited By (96)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7580383B2 (en) * | 2002-03-28 | 2009-08-25 | Gigaset Communications Gmbh | Adaptive modulation and other extensions of the physical layer in multiple access systems |
US11265787B2 (en) | 2003-02-24 | 2022-03-01 | Intellectual Ventures Ii Llc | Program for adjusting channel interference between access points in a wireless network |
US11916793B2 (en) | 2003-02-24 | 2024-02-27 | Intellectual Ventures Ii Llc | Program for adjusting channel interference between access points in a wireless network |
WO2004088886A3 (en) * | 2003-03-26 | 2005-01-20 | Conexant Systems Inc | Mechanism for reserving multiple channels in a wireless lan |
US7321762B2 (en) | 2003-03-26 | 2008-01-22 | Conexant Systems, Inc. | Mechanism for reserving multiple channels of a single medium access control and physical layer |
WO2004100480A1 (en) * | 2003-05-12 | 2004-11-18 | Siemens Aktiengesellschaft | Signaling for bit allocation in a wireless lan |
JP2008048440A (en) * | 2003-07-16 | 2008-02-28 | Interdigital Technol Corp | Method for storing mobile station physical measurements and mac performance statistics in management information base of access point |
US8724541B2 (en) | 2003-07-16 | 2014-05-13 | Intel Corporation | Method and apparatus for storing mobile station physical measurements and MAC performance statistics in a management information base of an access point |
US8340051B2 (en) | 2003-07-16 | 2012-12-25 | Intel Corporation | Method and apparatus for storing mobile station physical measurements and MAC performance statistics in a management information base of an access point |
US9948498B2 (en) | 2003-07-16 | 2018-04-17 | Intel Corporation | Method and apparatus for storing mobile station physical measurements and MAC performance statistics in a management information base of an access point |
US9319994B2 (en) | 2003-07-16 | 2016-04-19 | Intel Corporation | Method and apparatus for storing mobile station physical measurements and MAC performance statistics in a management information base of an access point |
WO2005029788A1 (en) * | 2003-09-23 | 2005-03-31 | British Telecommunications Public Limited Company | Decentralized channel selection in a self-organizing adhoc network |
US7565149B2 (en) | 2003-09-23 | 2009-07-21 | British Telecommunications Public Limited Company | Channel selection |
US8774098B2 (en) | 2003-10-15 | 2014-07-08 | Qualcomm Incorporated | Method, apparatus, and system for multiplexing protocol data units |
US9072101B2 (en) | 2003-10-15 | 2015-06-30 | Qualcomm Incorporated | High speed media access control and direct link protocol |
US9137087B2 (en) | 2003-10-15 | 2015-09-15 | Qualcomm Incorporated | High speed media access control |
US9226308B2 (en) | 2003-10-15 | 2015-12-29 | Qualcomm Incorporated | Method, apparatus, and system for medium access control |
KR100930136B1 (en) * | 2003-10-15 | 2009-12-07 | 콸콤 인코포레이티드 | High speed media access control |
US10660087B2 (en) | 2003-10-24 | 2020-05-19 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
US8199737B2 (en) | 2003-10-24 | 2012-06-12 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
EP3310006A1 (en) * | 2003-10-24 | 2018-04-18 | Sony Corporation | Reducing beacon collision probability |
EP1677456A4 (en) * | 2003-10-24 | 2010-06-02 | Sony Corp | Radio communication system, radio communication apparatus, radio communication method, and computer program |
EP2197158A2 (en) | 2003-10-24 | 2010-06-16 | Sony Corporation | Reducing beacon collision probability |
EP2197158A3 (en) * | 2003-10-24 | 2010-10-06 | Sony Corporation | Reducing beacon collision probability |
WO2005041487A1 (en) | 2003-10-24 | 2005-05-06 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
US9185698B2 (en) | 2003-10-24 | 2015-11-10 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
JP2007509549A (en) * | 2003-10-24 | 2007-04-12 | インターナショナル・ユニヴァーシティ・ブレーメン・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツング | Inter-cell interference mitigation technology using reservation indicator |
US7924867B2 (en) | 2003-10-24 | 2011-04-12 | Ntt Docomo, Inc. | Communications network using reservation indicator |
KR101031726B1 (en) * | 2003-10-24 | 2011-04-29 | 소니 주식회사 | Radio communication system, radio communication apparatus, radio communication method, and computer program |
US7995548B2 (en) | 2003-10-24 | 2011-08-09 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
EP1677456A1 (en) * | 2003-10-24 | 2006-07-05 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
US8400993B2 (en) | 2003-10-24 | 2013-03-19 | Sony Corporation | Radio communication system, radio communication apparatus, radio communication method, and computer program |
JP2007513550A (en) * | 2003-12-01 | 2007-05-24 | インターデイジタル テクノロジー コーポレーション | Wireless communication method and apparatus for implementing access point activation process and initial channel selection process |
US7818018B2 (en) | 2004-01-29 | 2010-10-19 | Qualcomm Incorporated | Distributed hierarchical scheduling in an AD hoc network |
US8903440B2 (en) | 2004-01-29 | 2014-12-02 | Qualcomm Incorporated | Distributed hierarchical scheduling in an ad hoc network |
US8315271B2 (en) | 2004-03-26 | 2012-11-20 | Qualcomm Incorporated | Method and apparatus for an ad-hoc wireless communications system |
US8355372B2 (en) | 2004-05-07 | 2013-01-15 | Qualcomm Incorporated | Transmission mode and rate selection for a wireless communication system |
US8401018B2 (en) | 2004-06-02 | 2013-03-19 | Qualcomm Incorporated | Method and apparatus for scheduling in a wireless network |
WO2006035070A1 (en) * | 2004-09-30 | 2006-04-06 | Siemens Aktiengesellschaft | Method for realizing a link adaptation in a mimo-ofdm transmission system |
US8578230B2 (en) | 2004-10-05 | 2013-11-05 | Qualcomm Incorporated | Enhanced block acknowledgement |
US7882412B2 (en) | 2004-10-05 | 2011-02-01 | Sanjiv Nanda | Enhanced block acknowledgement |
US8463308B2 (en) | 2004-10-20 | 2013-06-11 | Toshiba America Research, Inc. | Terminal transmit power control with link adaptation |
EP2357867A1 (en) * | 2004-10-20 | 2011-08-17 | Kabushiki Kaisha Toshiba | Terminal transmit power control with link adaptation |
EP1848122A1 (en) * | 2005-02-09 | 2007-10-24 | Mitsubishi Electric Corporation | Radio device and interference avoiding method by transmission power control |
EP1848122A4 (en) * | 2005-02-09 | 2009-04-29 | Mitsubishi Electric Corp | Radio device and interference avoiding method by transmission power control |
US7720502B2 (en) | 2005-02-09 | 2010-05-18 | Mitsubishi Electric Corporation | Radio device and interference avoiding method by transmission power control |
US8036676B2 (en) | 2005-02-14 | 2011-10-11 | Mitsubishi Electric Corporation | Frequency sharing method, receiving station and transmitting station |
JP2006279951A (en) * | 2005-03-28 | 2006-10-12 | Microsoft Corp | Neighbor location discovery with directional antennas in mesh network |
US9198194B2 (en) | 2005-09-12 | 2015-11-24 | Qualcomm Incorporated | Scheduling with reverse direction grant in wireless communication systems |
WO2007056081A1 (en) * | 2005-11-07 | 2007-05-18 | Thomson Licensing | Apparatus and method for transmit power control frequency selection in wireless networks |
US8681810B2 (en) | 2006-04-13 | 2014-03-25 | Qualcomm Incorporated | Dynamic carrier sensing thresholds |
US9008002B2 (en) | 2006-08-07 | 2015-04-14 | Qualcomm Incorporated | Conditional requests for asynchronous wireless communication |
US9661649B2 (en) | 2006-08-07 | 2017-05-23 | Qualcomm Incorporated | Determining a transmit parameter for wireless communication |
US8737313B2 (en) | 2006-08-07 | 2014-05-27 | Qualcomm Incorporated | Transmit time segments for asynchronous wireless communication |
US8416762B2 (en) | 2006-08-07 | 2013-04-09 | Qualcomm Incorporated | Message exchange scheme for asynchronous wireless communication |
US8340027B2 (en) | 2006-08-07 | 2012-12-25 | Qualcomm Incorporated | Monitor period for asynchronous wireless communication |
US8310996B2 (en) | 2006-08-07 | 2012-11-13 | Qualcomm Incorporated | Conditional scheduling for asynchronous wireless communication |
US10149252B2 (en) | 2007-07-06 | 2018-12-04 | Qualcomm Incorporated | Methods and apparatus related to interference management when sharing downlink bandwidth between wide area network usage and peer to peer signaling |
US8526410B2 (en) | 2007-07-06 | 2013-09-03 | Qualcomm Incorporated | Methods and apparatus related to interference management when sharing downlink bandwidth between wide area network usage and peer to peer signaling |
US8730841B2 (en) | 2007-07-06 | 2014-05-20 | Qualcomm Incorporated | Peer to peer communications methods and apparatus providing for use of both WAN uplink and downlink bands |
US9992750B2 (en) | 2007-07-06 | 2018-06-05 | Qualcomm Incorporated | Methods and apparatus related to interference management when sharing downlink bandwidth between wide area network usage and peer to peer signaling |
WO2009009453A2 (en) | 2007-07-10 | 2009-01-15 | Qualcomm Incorporated | Method and apparatus for power scaling in peer-to-peer communications |
US8140103B2 (en) | 2007-07-10 | 2012-03-20 | Qualcomm Incorporated | Method and apparatus for power scaling in peer-to-peer communications |
EP2590464B1 (en) * | 2007-07-10 | 2020-05-27 | Qualcomm Incorporated | Method and Apparatus for Power Scaling in Peer-to-Peer Communications |
WO2009009453A3 (en) * | 2007-07-10 | 2009-03-19 | Qualcomm Inc | Method and apparatus for power scaling in peer-to-peer communications |
EP2026474A3 (en) * | 2007-08-14 | 2013-08-21 | Canon Kabushiki Kaisha | Communication apparatus and communication control method for transmission power control |
US8098680B2 (en) | 2007-08-14 | 2012-01-17 | Motorola Mobility, Inc. | Method and system for managing transmissions in a wireless communication network |
EP2045930A1 (en) * | 2007-09-28 | 2009-04-08 | NTT DoCoMo, Inc. | Decentralized C/I power control for TDD |
US7839202B2 (en) | 2007-10-02 | 2010-11-23 | Qualcomm, Incorporated | Bandgap reference circuit with reduced power consumption |
US8588705B1 (en) | 2007-12-11 | 2013-11-19 | Marvell International Ltd. | System and method of determining Power over Ethernet impairment |
US8989669B2 (en) | 2008-06-16 | 2015-03-24 | Marvell World Trade Ltd. | Short-range wireless communication |
EP2635077A3 (en) * | 2008-06-16 | 2013-09-11 | Marvell World Trade Ltd. | Short-range wireless communication |
US8571479B2 (en) | 2008-06-16 | 2013-10-29 | Marvell World Trade Ltd. | Short-range wireless communication |
US8923788B1 (en) | 2008-06-27 | 2014-12-30 | Marvell International Ltd. | Circuit and method for adjusting a digitally controlled oscillator |
US9055460B1 (en) | 2008-08-11 | 2015-06-09 | Marvell International Ltd. | Location-based detection of interference in cellular communications systems |
US9629100B2 (en) | 2008-08-20 | 2017-04-18 | Qualcomm Incorporated | Power control for wireless LAN stations |
US9031044B2 (en) | 2008-08-20 | 2015-05-12 | Qualcomm Incorporated | Power control for wireless LAN stations |
US9655041B1 (en) | 2008-12-31 | 2017-05-16 | Marvell International Ltd. | Discovery-phase power conservation |
US8982826B1 (en) | 2009-04-24 | 2015-03-17 | Marvell International Ltd. | Method for transmitting information in a regulated spectrum and network configured to operate in the regulated spectrum |
US9066369B1 (en) | 2009-09-16 | 2015-06-23 | Marvell International Ltd. | Coexisting radio communication |
US8934353B2 (en) | 2009-10-08 | 2015-01-13 | Qualcomm Incorporated | Methods and apparatus for scaling transmit power of signals in wireless communications |
US8583159B2 (en) | 2009-10-08 | 2013-11-12 | Qualcomm Incorporated | Methods and apparatus for scaling transmit power of signals in wireless communications |
US9585025B2 (en) | 2011-02-16 | 2017-02-28 | Qualcomm Incorporated | Managing transmit power for better frequency re-use in TV white space |
WO2012112801A3 (en) * | 2011-02-16 | 2012-12-27 | Qualcomm Incorporated | Managing transmit power for better frequency re-use in tv white space |
US9813994B2 (en) | 2011-02-16 | 2017-11-07 | Qualcomm, Incorporated | Managing transmit power for better frequency re-use in TV white space |
WO2012112807A1 (en) * | 2011-02-16 | 2012-08-23 | Qualcomm Incorporated | Managing transmit power and modulation and coding scheme selection during random access in tv white space |
US9078108B1 (en) | 2011-05-26 | 2015-07-07 | Marvell International Ltd. | Method and apparatus for off-channel invitation |
US8983557B1 (en) | 2011-06-30 | 2015-03-17 | Marvell International Ltd. | Reducing power consumption of a multi-antenna transceiver |
EP3070980A4 (en) * | 2013-11-15 | 2016-11-16 | Huawei Tech Co Ltd | Power adjustment method and apparatus |
TWI611716B (en) * | 2014-07-18 | 2018-01-11 | 英特爾公司 | Mac protocol for full duplex wireless communications |
WO2016010675A1 (en) * | 2014-07-18 | 2016-01-21 | Intel Corporation | Mac protocol for full duplex wireless communications |
US20190274165A1 (en) * | 2018-03-01 | 2019-09-05 | Apple Inc. | Request to Send (RTS)/Clear to Send (CTS) Design in 5G |
CN110225548A (en) * | 2018-03-01 | 2019-09-10 | 苹果公司 | Request sends (RTS)/clear to send (CTS) design in 5G |
EP3534665A1 (en) * | 2018-03-01 | 2019-09-04 | Apple Inc. | Request to send (rts)/clear to send (cts) design in 5g |
US10925092B2 (en) | 2018-03-01 | 2021-02-16 | Apple Inc. | Request to send (RTS)/clear to send (CTS) using a self-contained slot |
CN110225548B (en) * | 2018-03-01 | 2022-09-06 | 苹果公司 | Request To Send (RTS)/Clear To Send (CTS) design in 5G |
Also Published As
Publication number | Publication date |
---|---|
DE60213583T2 (en) | 2007-10-18 |
EP1386419A2 (en) | 2004-02-04 |
JP2004533158A (en) | 2004-10-28 |
EP1386419B1 (en) | 2006-08-02 |
US7885680B2 (en) | 2011-02-08 |
ATE335316T1 (en) | 2006-08-15 |
CN1327635C (en) | 2007-07-18 |
US20020172186A1 (en) | 2002-11-21 |
CN1507704A (en) | 2004-06-23 |
ES2269676T3 (en) | 2007-04-01 |
DE60213583D1 (en) | 2006-09-14 |
AU2002253744A1 (en) | 2002-10-21 |
US20080076466A1 (en) | 2008-03-27 |
WO2002082751A3 (en) | 2003-11-27 |
US20080076465A1 (en) | 2008-03-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7885680B2 (en) | Instantaneous joint transmit power control and link adaptation for RTS/CTS based channel access | |
US10200115B2 (en) | Methods and systems for frequency multiplexed communication in dense wireless environments | |
JP4611374B2 (en) | Radio apparatus and interference avoidance method by transmission power control | |
US10834754B2 (en) | Systems and methods for improved communication efficiency in high efficiency wireless networks | |
US7804797B2 (en) | Communication control device and communication control method | |
US8463308B2 (en) | Terminal transmit power control with link adaptation | |
US9661649B2 (en) | Determining a transmit parameter for wireless communication | |
US20140328264A1 (en) | Systems and methods for coordination messaging using high efficiency wifi | |
EP3039937A1 (en) | Adaptive rts/cts in high-efficiency wireless communications | |
US11432247B2 (en) | Methods, systems and devices for varying wireless transmit power based on path loss information | |
US20230217521A1 (en) | Wireless communication method using multi-link, and wireless communication terminal using same | |
JP2020523846A (en) | Techniques for implementing communications in a wireless communications network | |
KR100924753B1 (en) | Channel Allocation Method using Power Controlled CTS in Multi-hop Networks | |
Zhou et al. | A novel power control algorithm and MAC protocol for CDMA-based mobile ad hoc network | |
Kim et al. | Proportional Fair Secondary Receiver Selection Algorithm for Full-duplex WLAN | |
Lee | Opportunistic Spatial Reuse in High-density WLANs | |
Max et al. | More capacity with the CSMA/IA MAC protocol in IEEE 802.11 s wireless mesh networks | |
CN117939607A (en) | Controlling transmit power across a Basic Service Set (BSS) | |
Ekici | Improvements and performance analysis of IEEE 80211 medium access protocols |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A2 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ OM PH PL PT RO RU SD SE SG SI SK SL TJ TM TN TR TT TZ UA UG UZ VN YU ZA ZM ZW |
|
AL | Designated countries for regional patents |
Kind code of ref document: A2 Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 828/MUMNP/2003 Country of ref document: IN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2002723005 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2002580582 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 028079698 Country of ref document: CN |
|
WWP | Wipo information: published in national office |
Ref document number: 2002723005 Country of ref document: EP |
|
REG | Reference to national code |
Ref country code: DE Ref legal event code: 8642 |
|
WWG | Wipo information: grant in national office |
Ref document number: 2002723005 Country of ref document: EP |