CA2241971A1 - Method and apparatus for improved control over cellular systems - Google Patents
Method and apparatus for improved control over cellular systems Download PDFInfo
- Publication number
- CA2241971A1 CA2241971A1 CA002241971A CA2241971A CA2241971A1 CA 2241971 A1 CA2241971 A1 CA 2241971A1 CA 002241971 A CA002241971 A CA 002241971A CA 2241971 A CA2241971 A CA 2241971A CA 2241971 A1 CA2241971 A1 CA 2241971A1
- Authority
- CA
- Canada
- Prior art keywords
- transmission characteristics
- wireless communications
- ones
- cells
- cell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000000034 method Methods 0.000 title claims abstract description 45
- 230000001413 cellular effect Effects 0.000 title claims abstract description 30
- 230000002441 reversible effect Effects 0.000 claims abstract description 13
- 238000012876 topography Methods 0.000 claims abstract description 7
- 230000005540 biological transmission Effects 0.000 claims description 76
- 230000000694 effects Effects 0.000 claims description 20
- 238000012544 monitoring process Methods 0.000 claims description 20
- 230000003466 anti-cipated effect Effects 0.000 claims description 8
- 230000001419 dependent effect Effects 0.000 claims description 4
- 238000004891 communication Methods 0.000 claims 97
- 230000000903 blocking effect Effects 0.000 claims 7
- 238000013507 mapping Methods 0.000 claims 4
- 230000008054 signal transmission Effects 0.000 claims 3
- 230000003044 adaptive effect Effects 0.000 claims 1
- 238000011156 evaluation Methods 0.000 claims 1
- 230000008569 process Effects 0.000 abstract description 13
- 238000012545 processing Methods 0.000 description 10
- 230000008901 benefit Effects 0.000 description 9
- 230000009471 action Effects 0.000 description 8
- 150000001768 cations Chemical class 0.000 description 8
- 230000002411 adverse Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 6
- 230000003993 interaction Effects 0.000 description 5
- 238000005457 optimization Methods 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 230000002452 interceptive effect Effects 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 230000002829 reductive effect Effects 0.000 description 3
- 238000000926 separation method Methods 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 2
- 230000002028 premature Effects 0.000 description 2
- 240000006829 Ficus sundaica Species 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 239000002674 ointment Substances 0.000 description 1
- 241000894007 species Species 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000002195 synergetic effect Effects 0.000 description 1
- 230000001960 triggered effect Effects 0.000 description 1
- 238000010200 validation analysis Methods 0.000 description 1
- NWONKYPBYAMBJT-UHFFFAOYSA-L zinc sulfate Chemical compound [Zn+2].[O-]S([O-])(=O)=O NWONKYPBYAMBJT-UHFFFAOYSA-L 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W24/00—Supervisory, monitoring or testing arrangements
- H04W24/02—Arrangements for optimising operational condition
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W24/00—Supervisory, monitoring or testing arrangements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
- H04W16/24—Cell structures
Abstract
System and apparatus for actively managing calls in a wireless cellular network. A host receives input data from a plurality of cells regarding the status of calls in that cell. Input data may include call variables such as carrier signal strength over interference (C/I), forward and reverse link power, beam and channel assignments, handoff status, and triangulation data regarding location/movement of active calls. The host processes the input data with reference to known cell neighborhoods, and creates output data for each cell that includes information on other active calls in the neighborhood. The output data then updates the cell with information regarding active calls in the cell's vicinity. The cell may then make adjustments to call variables taking into account local interference conditions. Further, through reference to (1) fixed data regarding the network such as topography or statistics, and/or (2) immediate past historical data regarding active calls, the host may also create output data taking into account predicted impending interference conditions.
Description
W O 97/24895 PCTrUS96/20901 ~ METHOD AND APPARATUS FOR IMPROVED
CONTROL OVER CELLU~AR SY~'1'~'~S
RELATED APPLICATIONS
Reference is hereby made to the following three co-pending and c~mmonly assigned U.S. Patent applications: APPARATUS, ~:iY~ hMS AND ~;'l'~OL~S FOR
AN'1'~NNA COMBINING IN WTRRT.R.~S COMMUNICATIONS SYSTEMS, Serial No. 08/488,793; MULTIPLE AN~1~NNA TRANSMISSION
SYSTEM, Serial No. 08/520,316; and S~l~ AND M~l~O~
FOR FREQu~N~Y MULTIPLEXING AN~1~NNA SIGNALS, Serial No.
08/520,000; the disclosures of which three applications are incorporated herein by reference.
TECHNICAL FIELD OF THE lNV~N'l'lON
This invention relates generally to the management of wireless commlln;cations in a cellular network, and more specifically to the use of a centralized host to monitor intelligently certain tr~n~mi~sion characteristics of potentially interfering comml~n; cations.
W O 97/24895 PCTrUS96~0901 BACKGRQU~DD OF THB lNv~lloN
It is known that the performance of wireless cnmm~ln;cations systems, and particularly mobile cellular systems, can be affected by a number of ~actors. Generally, such cellular systems are operated over these factors to achieve an optimum ratio of signal strength to interference ~C/I) for the reception experienced by each mobile user while still providing enough capacity throughout the system.
Recent advances have been made in addressing various of these individual factors that affect reception performance. The emergence of Code Division Multiple Access (CDMA) as a method of broadcasting multiple signals simultaneously on a single broad 1~ frequency band throughout the system has r~m~;~ted problems of co-channel interference and multi-path ~ading. The arrival of CDMA has also simplified cell-to-cell handoff procedures, creating a "soft" handoff that eliminates ~requency assignment and management.
Improvements in cellular capacity and call quality through the use of coordinated multiple antennas are also now known. For example, above-referenced co-pending and commonly assigned U.S. Patent applications APPARATUS, SYSTEMS AND METHODS FOR A~l~NNA COMBINING IN
WTRh~T.l;~.~S COMMUNICATIONS SYSTEMS and MUhTIPhE A~ NNA
TR~NSMISSION ~;Y~ [ teach substituting multiple narrow-beam antenna configurations ~or traditional single or three-face base-station antennas. According to these invention~, the use of time delay techni~ues with summing of the received CDM~ signal allows the output of multiple antennas to be combined and interpreted by receiver technology st~n~rd in the art. Among other improvements, these inventions allow assignment of a narrow tr~n~m;~sion beam between the base station and W O 97/24895 PCTrUS96/20901 the mobile, thereby reducing the potential ~or signal interference and facilitating forward-link and reverse-link power management.
Further innovation is taught in above-re~erenced co-pending, cnmmnn-y assigned U.S. Patent application SYSTEM AND METHOD FOR FRES~u~ Y MULTIPLEXING Al~ ;NNA
SIGNAhS, in which the down-m;~;ng and subsequent up-m,~;ng of the outputs of multiple antenna signals with pre-selected local oscillator ~requencies permit said signals to be combined and carried simultaneously on a reduced number o~ antenna cables.
A need now exists for an intelligent control system that will synergize the advantages offered by some of the foregoing recent innovations, thereby 1~ providing overall improved wireless service to the mobile user.
Moreover, the current art recognizes that cells in a cellular system also typically act autonomously within parameters set for the cellular system. The exception is in regard to handof~, where neighboring cells will typically coordinate a rh~nn~l change as a mobile enters a new cell. Especially in high interference environments, however, autonomous cell operation, substantially without reference to 2~ neighboring cells, can increase the potential for co-~.h~nn~l interference, possibly causing signal quality degradation or, worse still, loss of call or assignment of the signal to the wrong mobile.
Currently, the possibility of such co-ch~nn~l interference is m;n;m;zed by devising cell re-use patterns that adopt ~worst case assumptions" about required ch~nn~l bandwidth separation and physical spatial separation of cells. The available spectrum for each carrier normally consists of a plurality of rh~nnelg combined into 21 ch~nnel sets. These rh~nnel W O 97/24895 PCTrUS96~0901 sets are than separated by a m~;mnm physical distance in order to reduce co-ch~nnel interference. Since each cell i8 generally comprised of three 120-degree sectors, each sector has only seven channel sets to work with. Typically, a passive ~h~nnel re-use pattern is devised whereby it is left to a predet~rm~ne~
configuration of physical cell separation and neighboring ch~nn~l allocation to m;n;m;ze the potential ~or co-~h~nn~l interference.
An intelligent control system, in which cell operation and channel assignment i5 actively inter-coordinated, would there~ore also ~nh~nce cellular capacity. Further, by utilizing narrow beam technology such as disclosed in the above-referenced co-pending c~mmonly assigned U.S. patent application, dynamic beam control and power management could be combined with interactive rh~nnel assignment to provide a system with optimum capacity and reduced signal interference.
CA 0224l97l l998-06-30 W O 97/24895 PCTrUS96/209~1 SU~ RY OF THE lNv~NlloN
The present invention coordinates wireless commlln;cation activity within a cell with respect to R, a predetermined radius extending out ~rom the cell, within which neighborhood the activity o~ other cells will in~luence decisions to be made by the cell o~
interest. R may be selected so that one single controller ('Ihost'') may simultaneously coordinate the activity o~ all cells within an entire network. It will be readily appreciated, however, that as the number o~ cells simultaneously coordinated by one host increases (i.e. R increases), the number o~
interrelated decisions expected of the host increases exponentially, thus rapidly ~m~n~;ng great sophistication in the processing capability o~ the host .
It may there~ore not be feasible or even desirable to have just one host coordinating an entire network.
~ertainly, the breakdown o~ a single host controlling an entire network o~ cells could have catastrophic results. Advantageously, there~ore, a host could be used in combination with intelligence decentralized to cell base stations. In this alternative, the host's primary ~unction would be to receive in~ormation ~rom all cells, parse the information and assign such parsed portions to individual cells based on relevance to call activity in those cells, and then route the parsed portions to their assigned cells. Intelligence at the individual cell level could then control call activity within the cell based on interpreting the in~ormation provided by the host regarding conditions in the vicinity.
In this embo~;m~nt, it will be appreciated that each cell served by the host will have a ~neighbor list" o~ cells known to the host, which, by de~inition, W 097/24895 PCT~US96~0901 will be the vicinity of a particular cell in which prevailing conditions are of operational interest to the referenced cell. The "neighbor list~ may be as large or as small as other variables allow. Since the activity o~ cells outside this "neighbor list" i8, however, by definition not of interest to the re~erenced cell, the host may ignore conditions in such ~oreign" cells with respect to the referenced cell.
Another embodiment of the present invention contemplates that although decentralized intelligence ~rom the host to the cell might be advantageous, it i8 not a requirement. In this embo~;ment, therefore, one or more hosts control groups of cells centrally, making decisions centrally and sending direct instructions out to cells. In this embodiment, several hosts may be used to coordinate discrete or overlapping neighborhoods of cells. These hosts might act independently, or could be coordinated themselves by second and even higher levels of coordinating controllers.
A third embodiment recognizes that based on prevailing conditions in the network, the host could discriminate between data received from cells as to which data require real time processing to enable effective call management, and which can be processed o~f-line. In this way, host processing power may be used economically.
It will therefore be appreciated that the design of a cell neighborhood to be coordinated by a single host will depend on a combination o~ several variables -- the processing power of the host, the level of control intelligence desired to be decentralized to cell base stations, the "cell structure" to be controlled (number o~ cells in the neighborhood, the value of R selected, etc.), the level of inter-related CA 0224l97l l998-06-30 W O 97/24895 PCT~US96/20901 cell coordination desired, the volume o~ tra~ic expected, and 90 Eorth.
The in~ormation processed by the host for each cell will be dependent on calls being initiated by or in progre~s within that cell at a given m~m~nt in time.
The variables monitored by the host ~or each call within a cell may include:
(a) C/I;
(b) Forward link power;
(c) Reverse link power;
(d) Beam assignment;
(e) Cell assignment;
~) Channel assignment;
(g) Hando~ status; or (h) Triangulation o~ location/movement o~ call within the cell.
The host will receive in~ormation ~rom cells regarding one or more o~ these variables ~or each call active within the cell. Depending on how the host is con~igured to exercise control, the host may then correlate these variables ~or all active calls in a cell, cross-re~erence this in~ormation with similar in~ormation regarding active calls in the cell's "neighbor li~t," and then take action accordingly with respect to one or more calls. Alternatively, as described above, the host may parse in~ormation received and redirect such parsed portions as are relevant to individual cells. The individual cells may then take action with respect to calls active in the cell based upon the information sent by the host.
Further, as described in more detail below, in~ormation may also be stored, either at the host or by individual cells, to ~acilitate automated prediction o~ impending conditions to be experienced by calls based on immediate past in~ormation.
W 097/24895 PCT~US96/2~gOl In processing call information, a guiding st~n~rd to optimize call quality and service i8 advantageously to maintain acceptable C/I ~or each call.
Advantageously, all actions with respect to a call should have C/I in mind. While C/I r~m~;n~ optimized, actions may also be taken in furtherance of secondary objectives, such as m; n~ m; zing the call' 8 adverse influence on other calls in progress elsewhere in the neighborhood.
An example of such a call optimization process in more detail would be for the cell to select a ch~nnel and monitor for whether a call transmitter is active within that cell on that channel. If so, in accordance with the above-re~erenced co-pending and cnmmo~ly assigned patent application, the cell may then increment narrow antenna beams, measuring and identifying the beam assignment o~fering the strongest RSSI (nnm;n~lly the sum of C+I for that beam). Having identi~ied the beam with the strongest ~SSI, the cell may then refer to information most recently received ~rom the host on conditions prevailing nearby, and then det~rm;n~ if this beam assignment is acceptable with respect to its effect on nearby active calls. If not, the cell may then identify the beam with the second or third strongest RSSI and det~rmin~ if either of these beam assignments are acceptable in the context of prevailing conditions nearby. If such beam assignments are still unacceptable, the cell may then resort to taking action on the call, such as modifying forward and/or reverse link power, changing ~h~nn~l assignment, and 80 on, as further described below.
Forward link power is easily adjusted by in~ormation sent by the host to the cell. Reverse link power can be adjusted by tricking the cell into believing that the signal strength from the mobile has CA 0224l97l l998-06-30 W O 97l24895 PCT~US96/20901 deviated ~rom a predet~rm; n~l acceptable range, even though the signal strength is actually in that range.
This trick may be advantageously accomplished by deliberately ampli~ying or attenuating the mobile's RF
signal as received by the cell outside the acceptable range so as to trigger an arti~icial reverse link power boost or cut.
The present invention may also easily control beam assignment. Technology such as taught by above-referenced co-pending and cnmmonly assigned U.S. Patent applications APPAR~TUS, SYSTEMS AND METHODS FOR Al~ ;NNA
COMBINING IN WT~T~S COMMUNICATIONS SYSTEMS and MULTIPLE ANTENNA TRANSMISSION SYSTEM may advantageously ~acilitate this control. Beam assignment should advantageously discriminate between values o~ I (the inter~erence level) in similar values o~ C/I. In such cases, beams should be assigned according to lower values of I ~or a given carrier level. It may even be pre~erable to make beam assignments to antennas likely to experience lower values o~ C when the next logical beam assignment based on C is likely to experience unacceptably high I.
It will be understood that cell assignment control requires the ability to initiate hando~s as the mobile moves in and out o~ range o~ various cells. This is normally done at the cell base station level. The present invention may ~nh~nce control over call C/I, however, by altering cell assignment artificially in an appropriate situation. For example, I ~or a call in a 3~ given cell may have increased to where the call may actually bene~it ~rom a premature hando~ to a neighboring cell. Conversely, it may be advantageous to delay hando~ when I in the new cell is detected as being unacceptably high. The present invention may ~orce such arti~icial hando~s by reducing apparent C
W O 97/2489S PCT~US96/20901 for the call and tricking the cell assignment protocol into believing that a mobile i8 out of the cell's range. Methods of reducing apparent C include (1) not updating a beam assignment as a mobile moves beyond a beam's lobe, allowing the power to roll off as the mobile leaves the lobe, or (2) deliberately attenuating C to below a handoff level as it is received.
The same principles apply in controlling ~h~nn~l assignment. Again, premature or delayed handoffs may be triggered artificially in order to optimize C/I
experienced by a call and to reduce exposure o~ the call to conditions of high I.
The monitoring of handoff status by the present invention therefore becomes advantageous in order to facilitate the control over beam, cell and ch~nnel assignment described above.
It will be ~urther understood that the collection o~ triangulation data in~orming the present invention o~ the location and movement of active calls within cells will be highly advantageous. Knowledge of this in~ormation for multiple calls facilitates cross-re~erencing of conditions in neighboring cells to enable the control over call performance described above. In an embodiment where the host i8 parsing the collective information received from cells and redirecting portions back to individual cells based on relevance to those cells, knowledge o~ call location and ~ vel~ent within cells assists determ; n; ng the infonmation that will be relevant to a particular cell.
Furt~er, accumulated data regarding historical location and movement of calls within cells is also useful in predicting conditions likely to be experienced shortly by a call.
The present invention's ability to predict future conditions for calls is a feature directed to further W O 97/24895 PCTrUS96/20901 improve overall performance in successfully controlling calls. As noted, the relative location and mo~e.-.ellt of active calls through cells are important data in formulating such predictions. If memorialized periodically with some accuracy, these data may be combined with knowledge of prevailing conditions in cells and may thereby allow anticipation of impending potential adver~e conditions. Compensating action may then be made accordingly at the appropriate mnmen t.
Such performance has clear benefits over an uncoordinated system that merely reacts to adverse conditions when monitored.
The mobile's future movement through the cell may be predicted with further accuracy by tracking past movement against known data such as pr~m;n~nt traffic routes, time of day, street layout, etc. Further sophistication in movement prediction may be achieved by comparing past movement with known data regarding cell topography. For example, a mobile known to be travelling at 50 mph through a cell is very likely to follow the path of a major road.
Adverse conditions for a call may then anticipated by correlating the likely future movement of the referenced mobile with static conditions such as landscape topography, beam lobe and cell range, as well as dynamic conditions such as the likely interfering movement of other mobiles.
It will be further understood that the present invention's feature of continuously monitoring interactive cell conditions also provides additional advantages even when no calls are active in one or more cells. By continuing to monitor ~SSI within cells, even when there are no active calls, each cell may contribute data towards compilation of an "interference map,~' or 'II map". Information drawn from this ~I mapl' W O 97/24895 PCT~US96/20901 may then be used by nearby cells in which there are active cells to optimize the performance of those cells. This feature of compiling an "I map" for cnmmlln;ty use, even when call activity is light, is a ~urther synergistic advantage of the present invention.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description o~ the invention that follows may be better understood.
Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
~ .
CA 0224l97l l998-06-30 W O 97124895 13 PCT~US96/20901 BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete underst~n~;ng of the present invention, and the advantages thereo~, re~erence i8 now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a diagram illustrating the potential ~or inter~erence in a traditional cellular network 100.
FIG. 2 is a diagram illustrating how the potential ~or inter~erence in cellular network 100 may be reduced by management o~ beam assignments and other variables.
FIG. 3 is a diagram illustrating conceptually the present invention and its in~ormation ~low.
FIG. 4 is a logic ~low diagram illu~trating a presently preferred embodiment o~ the call optimization process taught by the present invention.
FIG. 5 is a logic ~low diagram illustrating a presently pre~erred embodiment o~ the call trac~ing process taught by the present invention.
FIG. 6 is a logic flow diagram illustrating a presently pre~erred embodiment o~ the cell/host interaction process taught by the present invention.
W O 97/24895 PCT~US96~0901 DET~TlJ~n DESCRIPTION OF THE lNV~NllON
FIG. l illustrates a wireless cellular comm-1n;cations system with traditional features known to generate the potential for call inter~erence.
Suppose that C i8 a cell of interest in cellular network l00. C i8 serving active mobile calls M1 and M2. C reaches M1 and M2 through C~s base station S.
It will be readily seen that in order to continue to serve M1, S must operate to a radius of Rcj the radius of cell interference, even though the radius required to cover C is only RCc the radius of cell coveraye. Rcj therefore tends to affect many cells unrelated to cnmmlln;cation between M1 and S.
An analogous effect is also typically caused by the mobile. Referring again to FIG. l, M2 actually requires to transmit only to R~ the radius of mobile coverage, in order to reach S. However, proper cnmm11n;cation at all times within Rc; requires M2 in fact to transmit to Rmj the radius of mobile interference. Again, it will be readily seen that Rm;
tends to af~ect many cells unrelated to comml-n;cation between M2 and S.
FIG. 2 illustrates how the foregoing problems are considerably r~m~ ted by coordinated management of narrow antenna beam assignment and other variables through a host, such as taught by the present invention. Suppose C1 and C2 are base stations in two cells of interest in cellular network l00, each operating an array of twelve narrow beams C1b1-C1b12 and C2b1-C2b12 respectively. M1 and M2 are active mobile calls being served by C1, while M~ and M4 are active mobile calls being served by C2. The host is not shown in FIG. 2, but is controlling in accordance with the principles taught by the present invention.
W O 97124895 PCT~US96/20901 It will be seen immediately that even if operating on the same ch~nnel~ there is almost no possibility of interference between M~ and M4. Referring back to FIG.
1, however, this likely would not 3~e the case absent narrow beam management. R";, the mobile interference radius for M1 and M4, would almost certainly overlap.
With regard to M2 and ~ on FIG. 2, there is a possibility for interference, especially if they are operating on the same ~h~nnel~ In this situation, the present invention could cause one of several actions to be taken to remove the potential for interference. The most logical action would be to change the ~h~nn~l assigned to one of the mobile calls. This alternative may not necessarily be available, however, depending on other prevailing conditions in cellular network 100. A
second alternative would be to attenuate forward or reverse link power for one ~or both) of M2 or M5.
Alternatively, assuming C/I would remain acceptable, a beam assignment change could be forced for one of the mobiles, say to Clbl for M2, or to C2bl0 for M3.
Following such a beam assignment change, it can be seen clearly ~rom FIG. 2 that the possibility is remote that M5 might encounter interference from C1b1, or that M2 might encounter interference from C2b10.
FIG. 3 illustrates in more detail how the present invention may process data in order to gain the advantages disclosed above. Cellular network 300 comprises a plurality of cells 310, each one ~.onnm;n;3ted individually Cl through Cn . Cells 310 periodically send input data 315 to host 320 regarding active calls in cells 310. Input data 315 may include values of~ C/I, forward or reverse link power, beam assignment, rh~nn~l assignment, handoff status or triangulation data pinpointing location/movement of active calls.
W O 97124895 16 PCTrUS96/20901 Host 320 includes CPU 330 and neighborhood group data 340. As ~urther described below, host 320 may also advantageously include ~ixed cell/network data 350 and/or active call history 360. CPU 330 accumulates input data 315 received ~rom cells 310, and processes it with respect to cell neighborhood group data 340.
The initial accumulation o~ input data 315 will also advantageously include sorting and validation thereo~.
Cell neighborhood group data 340 supplies CPU 330 with pre-defined relationships e~tablished between each o~ cells 310 and one or more o~ its neighbors within cellular network 300. These relationships group together, ~or each of cells 310, other cells in which call activity may af~ect the re~erenced cell.
In a ~irst embodiment herein, CPU 330 parses input data 315, and, upon reference to cell neighborhood group data 340, creates speci~ic output data 345 that, ~or each o~ cells 310, includes updated in~ormation on call activity in that cell' 8 neighborhood group. Host 320 then sends each o~ cells 310 its respective output data 345. Decentralized intelligence in cells 310 may then act upon output data 345, and then send updated input data 315 back to host 320 to initiate another management cycle.
The sophistication of output data 345 is also advantageously enhanced when CPU 330 creates output data 345 with reference to fixed cell/network data 350 and/or active call history 360. Fixed cell/network data 350 stores pre-identi~ied in~ormation regarding network 300 and cells 310 such as topography, street layouts, or statistics regarding geographic call volumes or peak cell usage times. Active call history 360 archives input data 315 as received ~rom cells 310.
Fixed cell/network data 350 and/or active call history 360 may then in~orm CPU to create output data 345 also W O 97/24895 17 PCT~US96/20901 with reference to ~ixed features in network 300 and with intelligence regarding ;mm~ te past history of active calls. In this way, in creating output data 345, CPU 330 may also anticipate impending conditions ~or active calls in ones of cells 310, and include that information in output data 345 to those cells. As noted above, an example of this predictive intelligence is ~or CPU 330 to use fixed cell/network data 350 and active call history 360 to recognize that an active call in one of cells 310 is travelling at speed along a major road. CPU 330 may then "prepare~' or "forewarn"
upcoming cells on the path of this road of the arrival of the call. Further, the impending interaction of this call with other active calls in the vicinity may also be anticipated. Further still, adjustments to this call may be scheduled to compensate for conditions expected to be encountered by this call as it travels its predicted path.
A second embodiment herein contemplates that there is little or no decentralized intelligence at cells 310, in which case CPU 330 will make central decisions on management of calls in cells, and then create output data 345 as a series of direct instructions to cells 310.
A third embodiment herein contemplates that CPU
330 may discriminate among input data 315 in deciding which require real time processing to manage calls effectively, and which may be processed off-line. For example, it will be understood that output data 345 regarding multiple active calls in close physical proximity are more likely to be needed to be created in real time in order to manage the calls e~fectively. On the other hand, particularly when there are few active calls, or the calls are widely dispersed, predictive W O 97/24895 18 PCTrUS96/20901 functions may be better suited to be processed off-line.
Referring to FIG. 4, an exemplary call optimization process i5 described, consistent with the first embodiment of the present invention as described above. The cell selects a ~h~nn~l to monitor (block 402), and then determ;nP~ whether there are active calls within the cell on that ch~nnel (block 404).
Either way, the cell will then increment narrow antenna beams in accordance with above-referenced, co-pending and cn~mQnly assigned U.S. patent applications APPAR~TUS, ~Y~ qS A~ID ~;l~OL~S FOR ANlhNr~A COMBINING IN
wTR~r.~.~s COMMUNICATIONS SY~ ~qS and MULTIPLE AN'l'l~:NNA
TRANSMISSION SY~l~S (blocks 406A and 406B).
If the cell detected no call activity on that ch~nnPl in block 404, then the cell nonetheless continues to measure RSSI as it increments antenna beams (block 408), and in doing so creates "I map"
within that cell for the information of other cells in which there may be call activity (block 401). It will be understood that the compilation of this "I map" may take place at either the cell or the host, depending on the desired level of decentralized processing expected of a cell.
If, on the other hand, the cell detects call activity on the ch~nnPl in block 404, it then increments antenna beams (block 406B) with a view to det~rm;n;ng which beam offers the strongest ~SSI for the call (block 412).
The cell may then analyze C/I for the call on the beam offering the strongest RSSI to detprm;ne whether that C/I is acceptable ~block 412). If it is, then the cell may assign that beam to that call (block 416). If not, the cell may then refer to the beams offering subse~uently lower values of RSSI, to determine whether W O 97/24895 PCT~US96/20901 call C/I would be acceptable on those beams (block 418). Ultimately, according to preselected parameters, the cell will either assign the call to a beam (block 416), or will identi~y that ~urther processing will be re~uire to optimize the call.
It will be recognized that such optimizing and det~rm;n~ng of acceptability needs to be made with re~erence to both improving C/I ~or the call and m;nimizing the impact o~ such optimization on other calls nearby. I~ the call may be optimized by modi~ying one o~ its attributes and such attribute modi~ication will not unacceptably a~ect C/I adversely ~or another active call elsewhere in the network (block 420), then the cell may proceed to make such attribute modi~ication (block 422). As described above, the cell's det~rm;n~tion of whether a call attribute modi~ication will adversely a~ect another active call elsewhere in the network may be with re~erence to information provided to the cell by the host regarding conditions in nearby cells. Further, as also described above, it will be understood that among the call attributes available to the cell ~or modi~ication are ~orward or reverse link power, channel assignment, and beam assignment.
Having modi~ied a call attribute (block 422), the cell may then return ~or a ~resh cycle o~ call optimization (block 424).
I~, however, the cell is unable to modi~y a call attribute without adversely a~ecting other active calls elsewhere, the cell may then report this status to the host and re~uest modi~ication o~ conditions o~
nearby cells so as to create conditions that will allow the call to be accommodated (block 426).
With re~erence to FIG. 5, an exemplary call tracking process is described, consistent with the W O 97/24895 PCTrUS96/20901 first embodiment described above, in which the cell does decentralized processing based on in~ormation regarding nearby cell conditions provided by the host.
The cell determ;nes the call~s current status (block 502) with reference to attributes described above, such as C/I, ~orward/reverse link power, beam and ch~nnel assignment, territorial location, etc. The cell may then predict the ~uture status o~ the call (block 504) with reference to said attributes, both by itsel~ and in relation to other influencing ~actors such as cell topography and the likely in~luence of other call activity nearby.
Having predicted the call's likely future status, corrections to certain attributes of the call may now be necessary to optimize the call with re~erence to both present and immediate ~uture conditions (blocks 506 and 508).
It may then be advantageous, although not essential, $or the cell to make adjustments to its earlier prediction o~ the call's ~uture status following changes in cell conditions while call attributes were beiny re-optimized (block 510).
Whether or not predictions for the call~ 5 ~uture status are updated, however, the cell may then determ; n~ if a bad call condition is likely in light of the overall call situation (block 512). If no bad call condition should be anticipated, the cell may then switch to a similar analysis cycle ~or another call, or repeat the cycle ~or this call (block 514).
I~, however, a bad call condition should be anticipated, the cell may in~orm the host (block 516) and may also ~lag the call as a priority for subsequent attention (block 518). The host may then inform cells near where the bad call condition is anticipated that W O 97/2489~ PCTAUS96120901 adjustments to calls under their control may be necessary to avoid the bad call condition.
FIG. 6 illustrates an exemplary cell/host interaction process where the host, in accordance with the ~irst embodiment described above, distributes information to cells regarding call activity nearby 80 that cells may make local adjustments to active calls based on that in~ormation. It will understood, however, that the logic flow disclosed by FIG. 6 is not dependent on any particular level of decentralization of processing from the host to the cell. Accordingly, unless specifically noted otherwise, the cell/host interaction process illustrated in FIG. 6 will be described below without reference to whether a 1~ particular step in the process will be executed by the cell or the host.
With reference to FIG. 6, there~ore, the present invention determines optimum conditions, such as antenna beam, power level or ~h~nnel assignment ~or a call without reference to interaction with other active calls (block 602). Determ;n~tion may then be made whether the attributes o~ this call, as optimized, impose any restrictions or otherwise impact other active calls in the same cell (blocks 604).
I~ in-cell restrictions or impacts are imposed, an alternative sub-optimum assignment for the call may be evaluated (block 606), or the attributes of other in-cell calls may be modified to facilitate co-existence of all calls (block 608).
I~ sub-optimum assignment is not ~easible, or i~
modi~ications to attributes of other in-cell calls are not available to allow complete co-existence, the present invention may have to block the call temporarily (block 610), at least until conditions for 3~ that call improve.
W O 97/2489~ PCT~US96/20901 Assuming the call can be optimized to co-exist with other in-cell calls, the present invention may then make an analysis as to whether the call will impose any restrictions or impacts on other out-of-cell calls (blocks 612, 614 and 616). If that analysis foresees a possible restriction or impact on another out-of-cell call, the present invention may det~rm; n~
whether this potential restriction or impact presents high risk of a bad call (block 618). If 80, then it may be possible for the host to lift one or more restrictions on affected calls so as to allow all calls to co-exist (block 620). Ultimately, throughout the process illustrated by FIG. 6, the call will either be assigned ~blocks 616) or blocked temporarily (blocks 15 : 610).
Although the present invention and its advantages have been described in detail J it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims .
CONTROL OVER CELLU~AR SY~'1'~'~S
RELATED APPLICATIONS
Reference is hereby made to the following three co-pending and c~mmonly assigned U.S. Patent applications: APPARATUS, ~:iY~ hMS AND ~;'l'~OL~S FOR
AN'1'~NNA COMBINING IN WTRRT.R.~S COMMUNICATIONS SYSTEMS, Serial No. 08/488,793; MULTIPLE AN~1~NNA TRANSMISSION
SYSTEM, Serial No. 08/520,316; and S~l~ AND M~l~O~
FOR FREQu~N~Y MULTIPLEXING AN~1~NNA SIGNALS, Serial No.
08/520,000; the disclosures of which three applications are incorporated herein by reference.
TECHNICAL FIELD OF THE lNV~N'l'lON
This invention relates generally to the management of wireless commlln;cations in a cellular network, and more specifically to the use of a centralized host to monitor intelligently certain tr~n~mi~sion characteristics of potentially interfering comml~n; cations.
W O 97/24895 PCTrUS96~0901 BACKGRQU~DD OF THB lNv~lloN
It is known that the performance of wireless cnmm~ln;cations systems, and particularly mobile cellular systems, can be affected by a number of ~actors. Generally, such cellular systems are operated over these factors to achieve an optimum ratio of signal strength to interference ~C/I) for the reception experienced by each mobile user while still providing enough capacity throughout the system.
Recent advances have been made in addressing various of these individual factors that affect reception performance. The emergence of Code Division Multiple Access (CDMA) as a method of broadcasting multiple signals simultaneously on a single broad 1~ frequency band throughout the system has r~m~;~ted problems of co-channel interference and multi-path ~ading. The arrival of CDMA has also simplified cell-to-cell handoff procedures, creating a "soft" handoff that eliminates ~requency assignment and management.
Improvements in cellular capacity and call quality through the use of coordinated multiple antennas are also now known. For example, above-referenced co-pending and commonly assigned U.S. Patent applications APPARATUS, SYSTEMS AND METHODS FOR A~l~NNA COMBINING IN
WTRh~T.l;~.~S COMMUNICATIONS SYSTEMS and MUhTIPhE A~ NNA
TR~NSMISSION ~;Y~ [ teach substituting multiple narrow-beam antenna configurations ~or traditional single or three-face base-station antennas. According to these invention~, the use of time delay techni~ues with summing of the received CDM~ signal allows the output of multiple antennas to be combined and interpreted by receiver technology st~n~rd in the art. Among other improvements, these inventions allow assignment of a narrow tr~n~m;~sion beam between the base station and W O 97/24895 PCTrUS96/20901 the mobile, thereby reducing the potential ~or signal interference and facilitating forward-link and reverse-link power management.
Further innovation is taught in above-re~erenced co-pending, cnmmnn-y assigned U.S. Patent application SYSTEM AND METHOD FOR FRES~u~ Y MULTIPLEXING Al~ ;NNA
SIGNAhS, in which the down-m;~;ng and subsequent up-m,~;ng of the outputs of multiple antenna signals with pre-selected local oscillator ~requencies permit said signals to be combined and carried simultaneously on a reduced number o~ antenna cables.
A need now exists for an intelligent control system that will synergize the advantages offered by some of the foregoing recent innovations, thereby 1~ providing overall improved wireless service to the mobile user.
Moreover, the current art recognizes that cells in a cellular system also typically act autonomously within parameters set for the cellular system. The exception is in regard to handof~, where neighboring cells will typically coordinate a rh~nn~l change as a mobile enters a new cell. Especially in high interference environments, however, autonomous cell operation, substantially without reference to 2~ neighboring cells, can increase the potential for co-~.h~nn~l interference, possibly causing signal quality degradation or, worse still, loss of call or assignment of the signal to the wrong mobile.
Currently, the possibility of such co-ch~nn~l interference is m;n;m;zed by devising cell re-use patterns that adopt ~worst case assumptions" about required ch~nn~l bandwidth separation and physical spatial separation of cells. The available spectrum for each carrier normally consists of a plurality of rh~nnelg combined into 21 ch~nnel sets. These rh~nnel W O 97/24895 PCTrUS96~0901 sets are than separated by a m~;mnm physical distance in order to reduce co-ch~nnel interference. Since each cell i8 generally comprised of three 120-degree sectors, each sector has only seven channel sets to work with. Typically, a passive ~h~nnel re-use pattern is devised whereby it is left to a predet~rm~ne~
configuration of physical cell separation and neighboring ch~nn~l allocation to m;n;m;ze the potential ~or co-~h~nn~l interference.
An intelligent control system, in which cell operation and channel assignment i5 actively inter-coordinated, would there~ore also ~nh~nce cellular capacity. Further, by utilizing narrow beam technology such as disclosed in the above-referenced co-pending c~mmonly assigned U.S. patent application, dynamic beam control and power management could be combined with interactive rh~nnel assignment to provide a system with optimum capacity and reduced signal interference.
CA 0224l97l l998-06-30 W O 97/24895 PCTrUS96/209~1 SU~ RY OF THE lNv~NlloN
The present invention coordinates wireless commlln;cation activity within a cell with respect to R, a predetermined radius extending out ~rom the cell, within which neighborhood the activity o~ other cells will in~luence decisions to be made by the cell o~
interest. R may be selected so that one single controller ('Ihost'') may simultaneously coordinate the activity o~ all cells within an entire network. It will be readily appreciated, however, that as the number o~ cells simultaneously coordinated by one host increases (i.e. R increases), the number o~
interrelated decisions expected of the host increases exponentially, thus rapidly ~m~n~;ng great sophistication in the processing capability o~ the host .
It may there~ore not be feasible or even desirable to have just one host coordinating an entire network.
~ertainly, the breakdown o~ a single host controlling an entire network o~ cells could have catastrophic results. Advantageously, there~ore, a host could be used in combination with intelligence decentralized to cell base stations. In this alternative, the host's primary ~unction would be to receive in~ormation ~rom all cells, parse the information and assign such parsed portions to individual cells based on relevance to call activity in those cells, and then route the parsed portions to their assigned cells. Intelligence at the individual cell level could then control call activity within the cell based on interpreting the in~ormation provided by the host regarding conditions in the vicinity.
In this embo~;m~nt, it will be appreciated that each cell served by the host will have a ~neighbor list" o~ cells known to the host, which, by de~inition, W 097/24895 PCT~US96~0901 will be the vicinity of a particular cell in which prevailing conditions are of operational interest to the referenced cell. The "neighbor list~ may be as large or as small as other variables allow. Since the activity o~ cells outside this "neighbor list" i8, however, by definition not of interest to the re~erenced cell, the host may ignore conditions in such ~oreign" cells with respect to the referenced cell.
Another embodiment of the present invention contemplates that although decentralized intelligence ~rom the host to the cell might be advantageous, it i8 not a requirement. In this embo~;ment, therefore, one or more hosts control groups of cells centrally, making decisions centrally and sending direct instructions out to cells. In this embodiment, several hosts may be used to coordinate discrete or overlapping neighborhoods of cells. These hosts might act independently, or could be coordinated themselves by second and even higher levels of coordinating controllers.
A third embodiment recognizes that based on prevailing conditions in the network, the host could discriminate between data received from cells as to which data require real time processing to enable effective call management, and which can be processed o~f-line. In this way, host processing power may be used economically.
It will therefore be appreciated that the design of a cell neighborhood to be coordinated by a single host will depend on a combination o~ several variables -- the processing power of the host, the level of control intelligence desired to be decentralized to cell base stations, the "cell structure" to be controlled (number o~ cells in the neighborhood, the value of R selected, etc.), the level of inter-related CA 0224l97l l998-06-30 W O 97/24895 PCT~US96/20901 cell coordination desired, the volume o~ tra~ic expected, and 90 Eorth.
The in~ormation processed by the host for each cell will be dependent on calls being initiated by or in progre~s within that cell at a given m~m~nt in time.
The variables monitored by the host ~or each call within a cell may include:
(a) C/I;
(b) Forward link power;
(c) Reverse link power;
(d) Beam assignment;
(e) Cell assignment;
~) Channel assignment;
(g) Hando~ status; or (h) Triangulation o~ location/movement o~ call within the cell.
The host will receive in~ormation ~rom cells regarding one or more o~ these variables ~or each call active within the cell. Depending on how the host is con~igured to exercise control, the host may then correlate these variables ~or all active calls in a cell, cross-re~erence this in~ormation with similar in~ormation regarding active calls in the cell's "neighbor li~t," and then take action accordingly with respect to one or more calls. Alternatively, as described above, the host may parse in~ormation received and redirect such parsed portions as are relevant to individual cells. The individual cells may then take action with respect to calls active in the cell based upon the information sent by the host.
Further, as described in more detail below, in~ormation may also be stored, either at the host or by individual cells, to ~acilitate automated prediction o~ impending conditions to be experienced by calls based on immediate past in~ormation.
W 097/24895 PCT~US96/2~gOl In processing call information, a guiding st~n~rd to optimize call quality and service i8 advantageously to maintain acceptable C/I ~or each call.
Advantageously, all actions with respect to a call should have C/I in mind. While C/I r~m~;n~ optimized, actions may also be taken in furtherance of secondary objectives, such as m; n~ m; zing the call' 8 adverse influence on other calls in progress elsewhere in the neighborhood.
An example of such a call optimization process in more detail would be for the cell to select a ch~nnel and monitor for whether a call transmitter is active within that cell on that channel. If so, in accordance with the above-re~erenced co-pending and cnmmo~ly assigned patent application, the cell may then increment narrow antenna beams, measuring and identifying the beam assignment o~fering the strongest RSSI (nnm;n~lly the sum of C+I for that beam). Having identi~ied the beam with the strongest ~SSI, the cell may then refer to information most recently received ~rom the host on conditions prevailing nearby, and then det~rm;n~ if this beam assignment is acceptable with respect to its effect on nearby active calls. If not, the cell may then identify the beam with the second or third strongest RSSI and det~rmin~ if either of these beam assignments are acceptable in the context of prevailing conditions nearby. If such beam assignments are still unacceptable, the cell may then resort to taking action on the call, such as modifying forward and/or reverse link power, changing ~h~nn~l assignment, and 80 on, as further described below.
Forward link power is easily adjusted by in~ormation sent by the host to the cell. Reverse link power can be adjusted by tricking the cell into believing that the signal strength from the mobile has CA 0224l97l l998-06-30 W O 97l24895 PCT~US96/20901 deviated ~rom a predet~rm; n~l acceptable range, even though the signal strength is actually in that range.
This trick may be advantageously accomplished by deliberately ampli~ying or attenuating the mobile's RF
signal as received by the cell outside the acceptable range so as to trigger an arti~icial reverse link power boost or cut.
The present invention may also easily control beam assignment. Technology such as taught by above-referenced co-pending and cnmmonly assigned U.S. Patent applications APPAR~TUS, SYSTEMS AND METHODS FOR Al~ ;NNA
COMBINING IN WT~T~S COMMUNICATIONS SYSTEMS and MULTIPLE ANTENNA TRANSMISSION SYSTEM may advantageously ~acilitate this control. Beam assignment should advantageously discriminate between values o~ I (the inter~erence level) in similar values o~ C/I. In such cases, beams should be assigned according to lower values of I ~or a given carrier level. It may even be pre~erable to make beam assignments to antennas likely to experience lower values o~ C when the next logical beam assignment based on C is likely to experience unacceptably high I.
It will be understood that cell assignment control requires the ability to initiate hando~s as the mobile moves in and out o~ range o~ various cells. This is normally done at the cell base station level. The present invention may ~nh~nce control over call C/I, however, by altering cell assignment artificially in an appropriate situation. For example, I ~or a call in a 3~ given cell may have increased to where the call may actually bene~it ~rom a premature hando~ to a neighboring cell. Conversely, it may be advantageous to delay hando~ when I in the new cell is detected as being unacceptably high. The present invention may ~orce such arti~icial hando~s by reducing apparent C
W O 97/2489S PCT~US96/20901 for the call and tricking the cell assignment protocol into believing that a mobile i8 out of the cell's range. Methods of reducing apparent C include (1) not updating a beam assignment as a mobile moves beyond a beam's lobe, allowing the power to roll off as the mobile leaves the lobe, or (2) deliberately attenuating C to below a handoff level as it is received.
The same principles apply in controlling ~h~nn~l assignment. Again, premature or delayed handoffs may be triggered artificially in order to optimize C/I
experienced by a call and to reduce exposure o~ the call to conditions of high I.
The monitoring of handoff status by the present invention therefore becomes advantageous in order to facilitate the control over beam, cell and ch~nnel assignment described above.
It will be ~urther understood that the collection o~ triangulation data in~orming the present invention o~ the location and movement of active calls within cells will be highly advantageous. Knowledge of this in~ormation for multiple calls facilitates cross-re~erencing of conditions in neighboring cells to enable the control over call performance described above. In an embodiment where the host i8 parsing the collective information received from cells and redirecting portions back to individual cells based on relevance to those cells, knowledge o~ call location and ~ vel~ent within cells assists determ; n; ng the infonmation that will be relevant to a particular cell.
Furt~er, accumulated data regarding historical location and movement of calls within cells is also useful in predicting conditions likely to be experienced shortly by a call.
The present invention's ability to predict future conditions for calls is a feature directed to further W O 97/24895 PCTrUS96/20901 improve overall performance in successfully controlling calls. As noted, the relative location and mo~e.-.ellt of active calls through cells are important data in formulating such predictions. If memorialized periodically with some accuracy, these data may be combined with knowledge of prevailing conditions in cells and may thereby allow anticipation of impending potential adver~e conditions. Compensating action may then be made accordingly at the appropriate mnmen t.
Such performance has clear benefits over an uncoordinated system that merely reacts to adverse conditions when monitored.
The mobile's future movement through the cell may be predicted with further accuracy by tracking past movement against known data such as pr~m;n~nt traffic routes, time of day, street layout, etc. Further sophistication in movement prediction may be achieved by comparing past movement with known data regarding cell topography. For example, a mobile known to be travelling at 50 mph through a cell is very likely to follow the path of a major road.
Adverse conditions for a call may then anticipated by correlating the likely future movement of the referenced mobile with static conditions such as landscape topography, beam lobe and cell range, as well as dynamic conditions such as the likely interfering movement of other mobiles.
It will be further understood that the present invention's feature of continuously monitoring interactive cell conditions also provides additional advantages even when no calls are active in one or more cells. By continuing to monitor ~SSI within cells, even when there are no active calls, each cell may contribute data towards compilation of an "interference map,~' or 'II map". Information drawn from this ~I mapl' W O 97/24895 PCT~US96/20901 may then be used by nearby cells in which there are active cells to optimize the performance of those cells. This feature of compiling an "I map" for cnmmlln;ty use, even when call activity is light, is a ~urther synergistic advantage of the present invention.
The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description o~ the invention that follows may be better understood.
Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
~ .
CA 0224l97l l998-06-30 W O 97124895 13 PCT~US96/20901 BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete underst~n~;ng of the present invention, and the advantages thereo~, re~erence i8 now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a diagram illustrating the potential ~or inter~erence in a traditional cellular network 100.
FIG. 2 is a diagram illustrating how the potential ~or inter~erence in cellular network 100 may be reduced by management o~ beam assignments and other variables.
FIG. 3 is a diagram illustrating conceptually the present invention and its in~ormation ~low.
FIG. 4 is a logic ~low diagram illu~trating a presently preferred embodiment o~ the call optimization process taught by the present invention.
FIG. 5 is a logic ~low diagram illustrating a presently pre~erred embodiment o~ the call trac~ing process taught by the present invention.
FIG. 6 is a logic flow diagram illustrating a presently pre~erred embodiment o~ the cell/host interaction process taught by the present invention.
W O 97/24895 PCT~US96~0901 DET~TlJ~n DESCRIPTION OF THE lNV~NllON
FIG. l illustrates a wireless cellular comm-1n;cations system with traditional features known to generate the potential for call inter~erence.
Suppose that C i8 a cell of interest in cellular network l00. C i8 serving active mobile calls M1 and M2. C reaches M1 and M2 through C~s base station S.
It will be readily seen that in order to continue to serve M1, S must operate to a radius of Rcj the radius of cell interference, even though the radius required to cover C is only RCc the radius of cell coveraye. Rcj therefore tends to affect many cells unrelated to cnmmlln;cation between M1 and S.
An analogous effect is also typically caused by the mobile. Referring again to FIG. l, M2 actually requires to transmit only to R~ the radius of mobile coverage, in order to reach S. However, proper cnmm11n;cation at all times within Rc; requires M2 in fact to transmit to Rmj the radius of mobile interference. Again, it will be readily seen that Rm;
tends to af~ect many cells unrelated to comml-n;cation between M2 and S.
FIG. 2 illustrates how the foregoing problems are considerably r~m~ ted by coordinated management of narrow antenna beam assignment and other variables through a host, such as taught by the present invention. Suppose C1 and C2 are base stations in two cells of interest in cellular network l00, each operating an array of twelve narrow beams C1b1-C1b12 and C2b1-C2b12 respectively. M1 and M2 are active mobile calls being served by C1, while M~ and M4 are active mobile calls being served by C2. The host is not shown in FIG. 2, but is controlling in accordance with the principles taught by the present invention.
W O 97124895 PCT~US96/20901 It will be seen immediately that even if operating on the same ch~nnel~ there is almost no possibility of interference between M~ and M4. Referring back to FIG.
1, however, this likely would not 3~e the case absent narrow beam management. R";, the mobile interference radius for M1 and M4, would almost certainly overlap.
With regard to M2 and ~ on FIG. 2, there is a possibility for interference, especially if they are operating on the same ~h~nnel~ In this situation, the present invention could cause one of several actions to be taken to remove the potential for interference. The most logical action would be to change the ~h~nn~l assigned to one of the mobile calls. This alternative may not necessarily be available, however, depending on other prevailing conditions in cellular network 100. A
second alternative would be to attenuate forward or reverse link power for one ~or both) of M2 or M5.
Alternatively, assuming C/I would remain acceptable, a beam assignment change could be forced for one of the mobiles, say to Clbl for M2, or to C2bl0 for M3.
Following such a beam assignment change, it can be seen clearly ~rom FIG. 2 that the possibility is remote that M5 might encounter interference from C1b1, or that M2 might encounter interference from C2b10.
FIG. 3 illustrates in more detail how the present invention may process data in order to gain the advantages disclosed above. Cellular network 300 comprises a plurality of cells 310, each one ~.onnm;n;3ted individually Cl through Cn . Cells 310 periodically send input data 315 to host 320 regarding active calls in cells 310. Input data 315 may include values of~ C/I, forward or reverse link power, beam assignment, rh~nn~l assignment, handoff status or triangulation data pinpointing location/movement of active calls.
W O 97124895 16 PCTrUS96/20901 Host 320 includes CPU 330 and neighborhood group data 340. As ~urther described below, host 320 may also advantageously include ~ixed cell/network data 350 and/or active call history 360. CPU 330 accumulates input data 315 received ~rom cells 310, and processes it with respect to cell neighborhood group data 340.
The initial accumulation o~ input data 315 will also advantageously include sorting and validation thereo~.
Cell neighborhood group data 340 supplies CPU 330 with pre-defined relationships e~tablished between each o~ cells 310 and one or more o~ its neighbors within cellular network 300. These relationships group together, ~or each of cells 310, other cells in which call activity may af~ect the re~erenced cell.
In a ~irst embodiment herein, CPU 330 parses input data 315, and, upon reference to cell neighborhood group data 340, creates speci~ic output data 345 that, ~or each o~ cells 310, includes updated in~ormation on call activity in that cell' 8 neighborhood group. Host 320 then sends each o~ cells 310 its respective output data 345. Decentralized intelligence in cells 310 may then act upon output data 345, and then send updated input data 315 back to host 320 to initiate another management cycle.
The sophistication of output data 345 is also advantageously enhanced when CPU 330 creates output data 345 with reference to fixed cell/network data 350 and/or active call history 360. Fixed cell/network data 350 stores pre-identi~ied in~ormation regarding network 300 and cells 310 such as topography, street layouts, or statistics regarding geographic call volumes or peak cell usage times. Active call history 360 archives input data 315 as received ~rom cells 310.
Fixed cell/network data 350 and/or active call history 360 may then in~orm CPU to create output data 345 also W O 97/24895 17 PCT~US96/20901 with reference to ~ixed features in network 300 and with intelligence regarding ;mm~ te past history of active calls. In this way, in creating output data 345, CPU 330 may also anticipate impending conditions ~or active calls in ones of cells 310, and include that information in output data 345 to those cells. As noted above, an example of this predictive intelligence is ~or CPU 330 to use fixed cell/network data 350 and active call history 360 to recognize that an active call in one of cells 310 is travelling at speed along a major road. CPU 330 may then "prepare~' or "forewarn"
upcoming cells on the path of this road of the arrival of the call. Further, the impending interaction of this call with other active calls in the vicinity may also be anticipated. Further still, adjustments to this call may be scheduled to compensate for conditions expected to be encountered by this call as it travels its predicted path.
A second embodiment herein contemplates that there is little or no decentralized intelligence at cells 310, in which case CPU 330 will make central decisions on management of calls in cells, and then create output data 345 as a series of direct instructions to cells 310.
A third embodiment herein contemplates that CPU
330 may discriminate among input data 315 in deciding which require real time processing to manage calls effectively, and which may be processed off-line. For example, it will be understood that output data 345 regarding multiple active calls in close physical proximity are more likely to be needed to be created in real time in order to manage the calls e~fectively. On the other hand, particularly when there are few active calls, or the calls are widely dispersed, predictive W O 97/24895 18 PCTrUS96/20901 functions may be better suited to be processed off-line.
Referring to FIG. 4, an exemplary call optimization process i5 described, consistent with the first embodiment of the present invention as described above. The cell selects a ~h~nn~l to monitor (block 402), and then determ;nP~ whether there are active calls within the cell on that ch~nnel (block 404).
Either way, the cell will then increment narrow antenna beams in accordance with above-referenced, co-pending and cn~mQnly assigned U.S. patent applications APPAR~TUS, ~Y~ qS A~ID ~;l~OL~S FOR ANlhNr~A COMBINING IN
wTR~r.~.~s COMMUNICATIONS SY~ ~qS and MULTIPLE AN'l'l~:NNA
TRANSMISSION SY~l~S (blocks 406A and 406B).
If the cell detected no call activity on that ch~nnPl in block 404, then the cell nonetheless continues to measure RSSI as it increments antenna beams (block 408), and in doing so creates "I map"
within that cell for the information of other cells in which there may be call activity (block 401). It will be understood that the compilation of this "I map" may take place at either the cell or the host, depending on the desired level of decentralized processing expected of a cell.
If, on the other hand, the cell detects call activity on the ch~nnPl in block 404, it then increments antenna beams (block 406B) with a view to det~rm;n;ng which beam offers the strongest ~SSI for the call (block 412).
The cell may then analyze C/I for the call on the beam offering the strongest RSSI to detprm;ne whether that C/I is acceptable ~block 412). If it is, then the cell may assign that beam to that call (block 416). If not, the cell may then refer to the beams offering subse~uently lower values of RSSI, to determine whether W O 97/24895 PCT~US96/20901 call C/I would be acceptable on those beams (block 418). Ultimately, according to preselected parameters, the cell will either assign the call to a beam (block 416), or will identi~y that ~urther processing will be re~uire to optimize the call.
It will be recognized that such optimizing and det~rm;n~ng of acceptability needs to be made with re~erence to both improving C/I ~or the call and m;nimizing the impact o~ such optimization on other calls nearby. I~ the call may be optimized by modi~ying one o~ its attributes and such attribute modi~ication will not unacceptably a~ect C/I adversely ~or another active call elsewhere in the network (block 420), then the cell may proceed to make such attribute modi~ication (block 422). As described above, the cell's det~rm;n~tion of whether a call attribute modi~ication will adversely a~ect another active call elsewhere in the network may be with re~erence to information provided to the cell by the host regarding conditions in nearby cells. Further, as also described above, it will be understood that among the call attributes available to the cell ~or modi~ication are ~orward or reverse link power, channel assignment, and beam assignment.
Having modi~ied a call attribute (block 422), the cell may then return ~or a ~resh cycle o~ call optimization (block 424).
I~, however, the cell is unable to modi~y a call attribute without adversely a~ecting other active calls elsewhere, the cell may then report this status to the host and re~uest modi~ication o~ conditions o~
nearby cells so as to create conditions that will allow the call to be accommodated (block 426).
With re~erence to FIG. 5, an exemplary call tracking process is described, consistent with the W O 97/24895 PCTrUS96/20901 first embodiment described above, in which the cell does decentralized processing based on in~ormation regarding nearby cell conditions provided by the host.
The cell determ;nes the call~s current status (block 502) with reference to attributes described above, such as C/I, ~orward/reverse link power, beam and ch~nnel assignment, territorial location, etc. The cell may then predict the ~uture status o~ the call (block 504) with reference to said attributes, both by itsel~ and in relation to other influencing ~actors such as cell topography and the likely in~luence of other call activity nearby.
Having predicted the call's likely future status, corrections to certain attributes of the call may now be necessary to optimize the call with re~erence to both present and immediate ~uture conditions (blocks 506 and 508).
It may then be advantageous, although not essential, $or the cell to make adjustments to its earlier prediction o~ the call's ~uture status following changes in cell conditions while call attributes were beiny re-optimized (block 510).
Whether or not predictions for the call~ 5 ~uture status are updated, however, the cell may then determ; n~ if a bad call condition is likely in light of the overall call situation (block 512). If no bad call condition should be anticipated, the cell may then switch to a similar analysis cycle ~or another call, or repeat the cycle ~or this call (block 514).
I~, however, a bad call condition should be anticipated, the cell may in~orm the host (block 516) and may also ~lag the call as a priority for subsequent attention (block 518). The host may then inform cells near where the bad call condition is anticipated that W O 97/2489~ PCTAUS96120901 adjustments to calls under their control may be necessary to avoid the bad call condition.
FIG. 6 illustrates an exemplary cell/host interaction process where the host, in accordance with the ~irst embodiment described above, distributes information to cells regarding call activity nearby 80 that cells may make local adjustments to active calls based on that in~ormation. It will understood, however, that the logic flow disclosed by FIG. 6 is not dependent on any particular level of decentralization of processing from the host to the cell. Accordingly, unless specifically noted otherwise, the cell/host interaction process illustrated in FIG. 6 will be described below without reference to whether a 1~ particular step in the process will be executed by the cell or the host.
With reference to FIG. 6, there~ore, the present invention determines optimum conditions, such as antenna beam, power level or ~h~nnel assignment ~or a call without reference to interaction with other active calls (block 602). Determ;n~tion may then be made whether the attributes o~ this call, as optimized, impose any restrictions or otherwise impact other active calls in the same cell (blocks 604).
I~ in-cell restrictions or impacts are imposed, an alternative sub-optimum assignment for the call may be evaluated (block 606), or the attributes of other in-cell calls may be modified to facilitate co-existence of all calls (block 608).
I~ sub-optimum assignment is not ~easible, or i~
modi~ications to attributes of other in-cell calls are not available to allow complete co-existence, the present invention may have to block the call temporarily (block 610), at least until conditions for 3~ that call improve.
W O 97/2489~ PCT~US96/20901 Assuming the call can be optimized to co-exist with other in-cell calls, the present invention may then make an analysis as to whether the call will impose any restrictions or impacts on other out-of-cell calls (blocks 612, 614 and 616). If that analysis foresees a possible restriction or impact on another out-of-cell call, the present invention may det~rm; n~
whether this potential restriction or impact presents high risk of a bad call (block 618). If 80, then it may be possible for the host to lift one or more restrictions on affected calls so as to allow all calls to co-exist (block 620). Ultimately, throughout the process illustrated by FIG. 6, the call will either be assigned ~blocks 616) or blocked temporarily (blocks 15 : 610).
Although the present invention and its advantages have been described in detail J it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims .
Claims (37)
1. A method for managing a plurality of wireless communications within a cellular network, comprising the steps of:
monitoring the transmission characteristics of ones of the wireless communications; and optimizing the transmission characteristics of wireless communications according to monitored transmission characteristics of nearby wireless communications;
wherein said optimizing step further comprises the steps of:
modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmission conditions for the sake of improving transmission conditions for other wireless communications; and temporarily blocking ones of the wireless communications if the articially sub-optimum transmission conditions are not feasible for wireless communications.
monitoring the transmission characteristics of ones of the wireless communications; and optimizing the transmission characteristics of wireless communications according to monitored transmission characteristics of nearby wireless communications;
wherein said optimizing step further comprises the steps of:
modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmission conditions for the sake of improving transmission conditions for other wireless communications; and temporarily blocking ones of the wireless communications if the articially sub-optimum transmission conditions are not feasible for wireless communications.
2. The method of claim 1, wherein the step of monitoring wireless communication transmission characteristics includes monitoring for one or more transmission characteristics selected from the group consisting of:
(a) communication signal strength;
(b) communication interference level;
(c) forward link signal power;
(d) reverse link signal power;
(e) cell assignment;
(f) antenna beam assignment;
(g) communication channel assignment;
(h) handoff status;
(i) territorial location of wireless communications within the cells;
(j) directional travel of mobile wireless communications within the cells; and (k) velocity of mobile wireless communications within the cells.
(a) communication signal strength;
(b) communication interference level;
(c) forward link signal power;
(d) reverse link signal power;
(e) cell assignment;
(f) antenna beam assignment;
(g) communication channel assignment;
(h) handoff status;
(i) territorial location of wireless communications within the cells;
(j) directional travel of mobile wireless communications within the cells; and (k) velocity of mobile wireless communications within the cells.
3. The method of claim 1, wherein the step of optimizing wireless communication transmission characteristics includes modifying one or more transmission characteristics selected from the group consisting of:
(a) communication signal strength;
(b) forward link signal power;
(c) reverse link signal power;
(d) cell assignment;
(e) antenna beam assignment;
(f) communication channel assignment; and (g) handoff status.
(a) communication signal strength;
(b) forward link signal power;
(c) reverse link signal power;
(d) cell assignment;
(e) antenna beam assignment;
(f) communication channel assignment; and (g) handoff status.
4. The method of claim 1, wherein the step of monitoring wireless communication transmission characteristics is performed centrally.
5. The method of claim 4, wherein the step of optimizing wireless communication transmission characteristics is also performed centrally.
6. Canceled.
7. A method for managing a plurality of wireless communications within a cellular network, comprising the steps of:
monitoring the transmission characteristics of ones of the wireless communications;
informing ones of the cells of the transmission characteristics of wireless communications monitored in nearby cells; and empowering cells to optimize the transmission characteristics of wireless communications according to information received regarding the transmission characteristics of wireless communications in nearby cells.
monitoring the transmission characteristics of ones of the wireless communications;
informing ones of the cells of the transmission characteristics of wireless communications monitored in nearby cells; and empowering cells to optimize the transmission characteristics of wireless communications according to information received regarding the transmission characteristics of wireless communications in nearby cells.
8. A method for managing a plurality of wireless communications within a cellular network, comprising the steps of:
monitoring the transmission characteristics of ones of the wireless communications;
discriminating between monitored wireless communication transmission characteristics according to a predetermined standard as to whether said monitored transmission characteristics need optimizing in real time or not;
for wireless communication transmission characteristics meeting said standard, optimizing said transmission characteristics in real time; and for wireless communication transmission characteristics not meeting said standard, optimizing said transmission characteristics on a schedule slower than real time.
monitoring the transmission characteristics of ones of the wireless communications;
discriminating between monitored wireless communication transmission characteristics according to a predetermined standard as to whether said monitored transmission characteristics need optimizing in real time or not;
for wireless communication transmission characteristics meeting said standard, optimizing said transmission characteristics in real time; and for wireless communication transmission characteristics not meeting said standard, optimizing said transmission characteristics on a schedule slower than real time.
9. A method for managing a plurality of wireless communications within a cellular network, comprising the steps of:
monitoring the transmission characteristics of ones of the wireless communications;
recording said monitored wireless communication transmission characteristics;
predicting future wireless communication transmission characteristics based on said wireless communication transmission characteristics records; and optimizing wireless communications transmission characteristics with reference to said predicted transmission characteristics.
monitoring the transmission characteristics of ones of the wireless communications;
recording said monitored wireless communication transmission characteristics;
predicting future wireless communication transmission characteristics based on said wireless communication transmission characteristics records; and optimizing wireless communications transmission characteristics with reference to said predicted transmission characteristics.
10. The method of claim 9, wherein the step of predicting wireless communication transmission characteristics is also performed with reference to pre-recorded network data.
11. The method of claim 10, wherein the pre-recorded network data include wireless communication activity statistics.
12. The method of claim 10, wherein the pre-recorded network data include territorial topography.
13. The method of claim 10, wherein the pre-recorded network data include prevailing signal interference level cartography.
14. A system for managing a plurality of wireless communications within a cellular network, comprising:
means for monitoring the transmission characteristics of ones of the wireless communications;
and means for optimizing the transmission characteristics of wireless communications according to monitored transmission characteristics of nearby wireless communications;
wherein the optimizing means further comprises:
means for modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmission conditions for the sake of improving transmission conditions for other wireless communications; and means for temporaily blocking ones of the wireless communications if the artificially sub-optimum transmission conditions are not feasible for wireless communications.
means for monitoring the transmission characteristics of ones of the wireless communications;
and means for optimizing the transmission characteristics of wireless communications according to monitored transmission characteristics of nearby wireless communications;
wherein the optimizing means further comprises:
means for modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmission conditions for the sake of improving transmission conditions for other wireless communications; and means for temporaily blocking ones of the wireless communications if the artificially sub-optimum transmission conditions are not feasible for wireless communications.
15. The system of claim 14, wherein the means for monitoring wireless communication transmission characteristics monitors one or more transmission characteristics selected from the group consisting of:
(a) communication signal strength;
(b) communication interference level;
(c) forward link signal power;
(d) reverse link signal power;
(e) cell assignment;
(f) antenna beam assignment;
(g) communication channel assignment;
(h) handoff status;
(i) territorial location of wireless communications within the cells;
(j) directional travel of mobile wireless communications within the cells; and (k) velocity of mobile wireless communications within the cells.
(a) communication signal strength;
(b) communication interference level;
(c) forward link signal power;
(d) reverse link signal power;
(e) cell assignment;
(f) antenna beam assignment;
(g) communication channel assignment;
(h) handoff status;
(i) territorial location of wireless communications within the cells;
(j) directional travel of mobile wireless communications within the cells; and (k) velocity of mobile wireless communications within the cells.
16. The system of claim 14, wherein the means for optimizing wireless communication transmission characteristics modifies one or more transmission characteristics selected from the group consisting of:
(a) communication signal strength;
(b) forward link signal power;
(c) reverse link signal power;
(d) cell assignment;
(e) antenna beam assignment;
(f) communication channel assignment; and (g) handoff status.
(a) communication signal strength;
(b) forward link signal power;
(c) reverse link signal power;
(d) cell assignment;
(e) antenna beam assignment;
(f) communication channel assignment; and (g) handoff status.
17. The system of claim 14, wherein the means for monitoring wireless communication transmission characteristics performs said monitoring centrally.
18. The system of claim 17, wherein the means for optimizing wireless communication transmission characteristics also performs said optimizing centrally.
19. Canceled.
20. A system for managing a plurality of wireless communications within a cellular network, comprising:
means for monitoring the transmission characteristics of ones of the wireless communications;
means for informing ones of the cells of the transmission characteristics of wireless communications monitored in nearby cells; and means for empowering cells to optimize the transmission characteristics of wireless communications according to information received regarding the transmission characteristics of wireless communications in nearby cells.
means for monitoring the transmission characteristics of ones of the wireless communications;
means for informing ones of the cells of the transmission characteristics of wireless communications monitored in nearby cells; and means for empowering cells to optimize the transmission characteristics of wireless communications according to information received regarding the transmission characteristics of wireless communications in nearby cells.
21. A system for managing a plurality of wireless communications within a cellular network, comprising:
means for monitoring the transmission characteristics of ones of the wireless communications;
means for discriminating between monitored wireless communication transmission characteristics according to a predetermined standard as to whether said monitored transmission characteristics need optimizing in real time or not;
means for optimizing wireless communication transmission characteristics meeting said standard in real time; and means for optimizing wireless communication transmission characteristics not meeting said standard on a schedule slower than real time.
means for monitoring the transmission characteristics of ones of the wireless communications;
means for discriminating between monitored wireless communication transmission characteristics according to a predetermined standard as to whether said monitored transmission characteristics need optimizing in real time or not;
means for optimizing wireless communication transmission characteristics meeting said standard in real time; and means for optimizing wireless communication transmission characteristics not meeting said standard on a schedule slower than real time.
22. A system for managing a plurality of wireless communications within a cellular network, comprising:
means for monitoring the transmission characteristics of ones of the wireless communications;
means for recording said monitored wireless communication transmission characteristics;
means for predicting future wireless communication transmission characteristics based on said wireless communication transmission characteristics records; and means for optimizing wireless communications transmission characteristics with reference to said predicted transmission characteristics.
means for monitoring the transmission characteristics of ones of the wireless communications;
means for recording said monitored wireless communication transmission characteristics;
means for predicting future wireless communication transmission characteristics based on said wireless communication transmission characteristics records; and means for optimizing wireless communications transmission characteristics with reference to said predicted transmission characteristics.
23. The system of claim 22, wherein the means for predicting wireless communication transmission characteristics performs said prediction with reference to pre-recorded network data.
24. The system of claim 23, wherein the pre-recorded network data include wireless communication activity statistics.
25. The system of claim 24, wherein the pre-recorded network data include territorial topography.
26. The system of claim 23, wherein the pre-recorded network data include prevailing signal interference cartography.
27. A method for compiling prevailing signal interference data for use in managing wireless communications in a cellular network, comprising the steps of:
dividing ones of the cells into zones;
monitoring ones of the zones for signal interference levels prevailing therein;
mapping a plurality of said monitored zones with their associated monitored prevailing signal interference levels; and extrapolating information from said map regarding likely signal interference levels at points in and around the zones;
whereby said map information may then be used for wireless communication management within the network.
dividing ones of the cells into zones;
monitoring ones of the zones for signal interference levels prevailing therein;
mapping a plurality of said monitored zones with their associated monitored prevailing signal interference levels; and extrapolating information from said map regarding likely signal interference levels at points in and around the zones;
whereby said map information may then be used for wireless communication management within the network.
28. The method of claim 27, wherein each zone is monitored by a separate narrow beam antenna.
29. The method of claim 27, in which the step of monitoring is performed without reference to wireless communication activity in any ones of the cells.
30. The method of claim 27, in which the step of monitoring is performed centrally.
31. The method of claim 27, in which the step of mapping is performed centrally.
32. The method of claim 27, in which the step of mapping further comprises:
remotely mapping ones of the zones with their associated monitored prevailing signal interference levels to compile a plurality of substantially contiguous maps; and centrally combining ones of said substantially contiguous maps to compile a regional map.
remotely mapping ones of the zones with their associated monitored prevailing signal interference levels to compile a plurality of substantially contiguous maps; and centrally combining ones of said substantially contiguous maps to compile a regional map.
33. A method of managing wireless communications between a base station and at least one active mobile station within a cellular network, comprising the steps of:
monitoring transmission characteristics of the wireless communications;
tracking the territorial movement of ones of the active mobile stations;
anticipating the likely future travels of said tracked mobile stations;
predicting future signal transmission conditions likely to prevail between the base station and the active mobile stations as said tracked mobile stations move along their anticipated travels;
predicting future adjustments to ones of the wireless communications transmission characteristics likely to optimize wireless communications as said tracked mobile stations encounter said predicted future signal transmission conditions;
scheduling said adjustments according to the anticipated travels of said tracked mobiles; and executing said adjustments according to said schedule.
monitoring transmission characteristics of the wireless communications;
tracking the territorial movement of ones of the active mobile stations;
anticipating the likely future travels of said tracked mobile stations;
predicting future signal transmission conditions likely to prevail between the base station and the active mobile stations as said tracked mobile stations move along their anticipated travels;
predicting future adjustments to ones of the wireless communications transmission characteristics likely to optimize wireless communications as said tracked mobile stations encounter said predicted future signal transmission conditions;
scheduling said adjustments according to the anticipated travels of said tracked mobiles; and executing said adjustments according to said schedule.
34. The method of claim 33, wherein the step of anticipating the likely future travels of mobile stations includes reference to one or more data sets selected from the group consisting of:
(a) pre-established topographical data;
(b) current active mobile station movement data;
(c) historical mobile station movement data;
(d) current wireless communication density data;
(e) historical wireless communication density data; and (f) historical peak-usage mobile station activity data.
(a) pre-established topographical data;
(b) current active mobile station movement data;
(c) historical mobile station movement data;
(d) current wireless communication density data;
(e) historical wireless communication density data; and (f) historical peak-usage mobile station activity data.
35. The method of claim 33, wherein the step of predicting likely future signal transmission conditions includes reference to one or more data sets selected from the group consisting of:
(a) pre-established topographical data;
(b) current regional signal interference cartographical data;
(c) historical regional signal interference cartographical data; and (d) anticipated path data for one or more current active calls.
(a) pre-established topographical data;
(b) current regional signal interference cartographical data;
(c) historical regional signal interference cartographical data; and (d) anticipated path data for one or more current active calls.
36. The method of claim 33, wherein the step of predicting future adjustments includes reference to historical data on adjustments to wireless communications transmission characteristics.
37. The method of claim 33, wherein the step of executing said adjustments includes modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmission conditions for the sake of improving transmission conditions for other wireless communications.
STATEMENT UNDER ARTICLE 19(1) Applicant has amended claims 1 and 14. Claim 1 has been amended to include the limitations of dependent claim 6 and claim 14 has been amended to include the limitations of dependent claim 19. Claims 6 and 19 have been canceled.
Claims 1 and 14 also include additional amendments directed to "temporarily blocking ones of the wireless communications." These amendments are clearly supported by the original disclosure at page 21, in lines 25-35. The amendments to claims 1 and 14 have no impact on the disclosure and drawings as filed.
Claims 1 and 14, as amended, require "modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmision conditions for the sake of improving transmision conditions for other wireless communications" and "temporarily blocking ones of the wireless communications if the artificially sub-optimum transmission conditions are not feasible for wireless communications."
European Patent Application number 90313301.5, entitled CELLULAR
RADIOTELEPHONE DIAGNOSTIC SYSTEM, fails to teach either of these elements. The disclosed Diagnostic System monitors and optimizes the transmission characteristics of wireless communications. However, the disclosure does not provide for operation at "artificially sub-optimum transmission conditions" or for "temporarily blocking ones of the wireless communications" as required by the present amendments to claims 1 and 14.
European Patent Application number 93202280.9 (corresponding to United States Patent No. 5,475,868, entitled CELLULAR RADIO SYSTEM HAVING
CHANNEL EVALUATION AND OPTIMAL CHANNEL SELECTION VIA TRIAL
USE OF NON-ASSIGNED CHANNELS) teaches a system for selecting cellular radio channels. However, the system does not disclose operation at "artificiallysub-optimum transmission conditions" or "temporarily blocking ones of the wireless communications" as required by the present amendments to claims 1 and 14.
The article entitled "Adaptive Channel Allocation in TACS" by M. Almgren, et al. discloses a method of assigning channels to a base station based upon channel transmission characteristics. However, the article does not teach a system that operates at "artificially sub-optimum transmission conditions" or that is capable of "temporarily blocking ones of the wireless communications" as required by claims 1 and 14, as amended.
STATEMENT UNDER ARTICLE 19(1) Applicant has amended claims 1 and 14. Claim 1 has been amended to include the limitations of dependent claim 6 and claim 14 has been amended to include the limitations of dependent claim 19. Claims 6 and 19 have been canceled.
Claims 1 and 14 also include additional amendments directed to "temporarily blocking ones of the wireless communications." These amendments are clearly supported by the original disclosure at page 21, in lines 25-35. The amendments to claims 1 and 14 have no impact on the disclosure and drawings as filed.
Claims 1 and 14, as amended, require "modifying ones of the transmission characteristics so as to allow ones of the wireless communications to continue at artificially sub-optimum transmision conditions for the sake of improving transmision conditions for other wireless communications" and "temporarily blocking ones of the wireless communications if the artificially sub-optimum transmission conditions are not feasible for wireless communications."
European Patent Application number 90313301.5, entitled CELLULAR
RADIOTELEPHONE DIAGNOSTIC SYSTEM, fails to teach either of these elements. The disclosed Diagnostic System monitors and optimizes the transmission characteristics of wireless communications. However, the disclosure does not provide for operation at "artificially sub-optimum transmission conditions" or for "temporarily blocking ones of the wireless communications" as required by the present amendments to claims 1 and 14.
European Patent Application number 93202280.9 (corresponding to United States Patent No. 5,475,868, entitled CELLULAR RADIO SYSTEM HAVING
CHANNEL EVALUATION AND OPTIMAL CHANNEL SELECTION VIA TRIAL
USE OF NON-ASSIGNED CHANNELS) teaches a system for selecting cellular radio channels. However, the system does not disclose operation at "artificiallysub-optimum transmission conditions" or "temporarily blocking ones of the wireless communications" as required by the present amendments to claims 1 and 14.
The article entitled "Adaptive Channel Allocation in TACS" by M. Almgren, et al. discloses a method of assigning channels to a base station based upon channel transmission characteristics. However, the article does not teach a system that operates at "artificially sub-optimum transmission conditions" or that is capable of "temporarily blocking ones of the wireless communications" as required by claims 1 and 14, as amended.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08/582,525 | 1996-01-03 | ||
| US08/582,525 US5884147A (en) | 1996-01-03 | 1996-01-03 | Method and apparatus for improved control over cellular systems |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2241971A1 true CA2241971A1 (en) | 1997-07-10 |
Family
ID=24329489
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002241971A Abandoned CA2241971A1 (en) | 1996-01-03 | 1996-12-31 | Method and apparatus for improved control over cellular systems |
Country Status (5)
| Country | Link |
|---|---|
| US (1) | US5884147A (en) |
| AU (1) | AU1569597A (en) |
| CA (1) | CA2241971A1 (en) |
| IL (1) | IL125275A0 (en) |
| WO (1) | WO1997024895A2 (en) |
Families Citing this family (39)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI105596B (en) * | 1996-05-27 | 2000-09-15 | Nokia Networks Oy | A method for determining the location of a mobile station |
| US20020108116A1 (en) * | 1997-04-16 | 2002-08-08 | Dillon Douglas M. | Satellite broadcasting system employing channel switching |
| FI106287B (en) | 1997-09-17 | 2000-12-29 | Nokia Mobile Phones Ltd | Improved procedure for changing base station |
| FI106289B (en) * | 1997-09-30 | 2000-12-29 | Nokia Mobile Phones Ltd | Procedure for selecting a cell and a mobile station |
| US6118767A (en) * | 1997-11-19 | 2000-09-12 | Metawave Communications Corporation | Interference control for CDMA networks using a plurality of narrow antenna beams and an estimation of the number of users/remote signals present |
| US6178333B1 (en) * | 1998-04-15 | 2001-01-23 | Metawave Communications Corporation | System and method providing delays for CDMA nulling |
| US6625135B1 (en) * | 1998-05-11 | 2003-09-23 | Cargenie Mellon University | Method and apparatus for incorporating environmental information for mobile communications |
| GB9810394D0 (en) * | 1998-05-14 | 1998-07-15 | Simoco Europ Limited | Radio communications system |
| US6594238B1 (en) * | 1998-06-19 | 2003-07-15 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and apparatus for dynamically adapting a connection state in a mobile communications system |
| US6157840A (en) * | 1998-08-31 | 2000-12-05 | Motorola Inc. | Method and apparatus for real-time channel resource allocation in a communications system |
| US6351642B1 (en) * | 1998-12-22 | 2002-02-26 | Telefonaktiebolaget Lm Ericsson (Publ) | CDMA soft hand-off |
| AU3685200A (en) * | 1999-02-26 | 2000-09-14 | Telefonaktiebolaget Lm Ericsson (Publ) | Smart antenna beam assignment at mobile station hand-off |
| US6418327B1 (en) | 1999-04-06 | 2002-07-09 | Spike Broadband Systems, Inc. | Methods and determining an optimum sector distribution within a coverage area of a wireless communication system |
| EP1205037A1 (en) * | 1999-07-26 | 2002-05-15 | Telefonaktiebolaget L M Ericsson (Publ) | Initial uplink and downlink power level assignment in a radio telecommunications network |
| KR100585831B1 (en) * | 1999-08-07 | 2006-06-01 | 에스케이 텔레콤주식회사 | Apparatus and method for improving quality of reverse signal in CDMA system |
| US6611500B1 (en) * | 1999-11-04 | 2003-08-26 | Lucent Technologies, Inc. | Methods and apparatus for derivative-based optimization of wireless network performance |
| AU773818B2 (en) * | 1999-11-30 | 2004-06-10 | Caterpillar Inc. | Method and apparatus for dynamically updating representations of a work site and a propagation model |
| US7447509B2 (en) * | 1999-12-22 | 2008-11-04 | Celeritasworks, Llc | Geographic management system |
| US6343290B1 (en) | 1999-12-22 | 2002-01-29 | Celeritas Technologies, L.L.C. | Geographic network management system |
| US8452776B2 (en) * | 1999-12-22 | 2013-05-28 | Celeritasworks, Llc | Spatial data portal |
| US6496694B1 (en) * | 2000-01-13 | 2002-12-17 | Intel Corporation | Wireless local loop with intelligent base station |
| US6970721B1 (en) | 2000-01-25 | 2005-11-29 | Lucent Technologies Inc. | Apparatus and method for measuring and controlling the performance or an adjustable antenna on a sub-sector basis |
| EP1278871A2 (en) * | 2000-04-29 | 2003-01-29 | MERCK PATENT GmbH | Human phospholipase c delta 5 |
| US6487414B1 (en) | 2000-08-10 | 2002-11-26 | Schema Ltd. | System and method for frequency planning in wireless communication networks |
| US6993138B1 (en) * | 2000-09-14 | 2006-01-31 | Nortel Networks Limited | Spatial key trees for key management in wireless environments |
| US7043270B2 (en) * | 2001-08-13 | 2006-05-09 | Andrew Corporation | Shared tower system for accomodating multiple service providers |
| US20030114165A1 (en) * | 2001-12-07 | 2003-06-19 | Mills Donald Charles | Method for enhanced wireless signal distribution |
| US6983174B2 (en) * | 2002-09-18 | 2006-01-03 | Andrew Corporation | Distributed active transmit and/or receive antenna |
| US6906681B2 (en) * | 2002-09-27 | 2005-06-14 | Andrew Corporation | Multicarrier distributed active antenna |
| US6844863B2 (en) | 2002-09-27 | 2005-01-18 | Andrew Corporation | Active antenna with interleaved arrays of antenna elements |
| US7280848B2 (en) * | 2002-09-30 | 2007-10-09 | Andrew Corporation | Active array antenna and system for beamforming |
| US6957074B2 (en) * | 2002-12-26 | 2005-10-18 | Nokia Corporation | Apparatus, and an associated method, for reserving resources in a mobile communication system through the use of historical indicia |
| US6972622B2 (en) * | 2003-05-12 | 2005-12-06 | Andrew Corporation | Optimization of error loops in distributed power amplifiers |
| US20060041534A1 (en) * | 2004-05-24 | 2006-02-23 | Atwell Micah E | Remote infrastructure management |
| US7684342B2 (en) * | 2004-11-03 | 2010-03-23 | Intel Corporation | Media independent trigger model for multiple network types |
| JP2008079079A (en) * | 2006-09-22 | 2008-04-03 | Fujitsu Ltd | Mobile terminal reconnection control method and device |
| EP2031920A1 (en) * | 2007-06-29 | 2009-03-04 | Nokia Siemens Networks Oy | Method for handover data acqusition in a cellular communications network and communications network |
| US20150038140A1 (en) | 2013-07-31 | 2015-02-05 | Qualcomm Incorporated | Predictive mobility in cellular networks |
| US9474000B2 (en) | 2013-07-31 | 2016-10-18 | Qualcomm Incorporated | Handover and reselection searching using predictive mobility |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE465146B (en) * | 1989-03-03 | 1991-07-29 | Televerket | METHOD FOR DISTRIBUTING A GIVEN NUMBER OF RADIO CHANNELS IN A RADIO SYSTEM |
| US5023900A (en) * | 1989-12-07 | 1991-06-11 | Tayloe Daniel R | Cellular radiotelephone diagnostic system |
| IL100213A (en) * | 1990-12-07 | 1995-03-30 | Qualcomm Inc | CDMA microcellular telephone system and distributed antenna system therefor |
| US5369786A (en) * | 1991-05-01 | 1994-11-29 | Motorola, Inc. | Enhanced power level usage in a radiotelephone system |
| JPH05268128A (en) * | 1992-03-18 | 1993-10-15 | Kokusai Denshin Denwa Co Ltd <Kdd> | Cdma communication system |
| US5285494A (en) * | 1992-07-31 | 1994-02-08 | Pactel Corporation | Network management system |
| AU670955B2 (en) * | 1992-08-04 | 1996-08-08 | Koninklijke Philips Electronics N.V. | Mobile radio system |
| GB2281175B (en) * | 1993-08-12 | 1998-04-08 | Northern Telecom Ltd | Base station antenna arrangement |
| US5570412A (en) * | 1994-09-28 | 1996-10-29 | U.S. West Technologies, Inc. | System and method for updating a location databank |
| GB2300091B (en) * | 1994-10-27 | 1999-04-14 | Motorola Inc | Methods of demand-based adaptive channel reuse for telecommunication systems |
-
1996
- 1996-01-03 US US08/582,525 patent/US5884147A/en not_active Expired - Lifetime
- 1996-12-31 IL IL12527596A patent/IL125275A0/en unknown
- 1996-12-31 AU AU15695/97A patent/AU1569597A/en not_active Abandoned
- 1996-12-31 WO PCT/US1996/020901 patent/WO1997024895A2/en active Application Filing
- 1996-12-31 CA CA002241971A patent/CA2241971A1/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| WO1997024895A2 (en) | 1997-07-10 |
| IL125275A0 (en) | 1999-04-11 |
| WO1997024895A3 (en) | 1998-03-05 |
| AU1569597A (en) | 1997-07-28 |
| MX9805464A (en) | 1998-10-31 |
| US5884147A (en) | 1999-03-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5884147A (en) | Method and apparatus for improved control over cellular systems | |
| US6832074B2 (en) | Method and system for real time cellular network configuration | |
| US5953661A (en) | Method of maximizing spectral efficiency in a cellular communications system | |
| US6539227B1 (en) | Methods and systems for controlling hard and soft handoffs in radio communications systems | |
| US4736453A (en) | Method and apparatus for making frequency channel assignment in a cellular or non-cellular radiotelephone communications system | |
| EP1266536B1 (en) | Position assisted handoff within a wireless communications network | |
| EP0737398B1 (en) | Method of allocating communication resources in a communication system | |
| US6987793B2 (en) | Predictive collision avoidance in macrodiverse wireless networks with frequency hopping using switching | |
| EP0983704B1 (en) | Channel selection in a radio link system | |
| EP1332636B1 (en) | Cellular radio network reusing frequencies | |
| US6212386B1 (en) | Automated tool method for frequency plan revision within a cellular telephone system | |
| KR100375282B1 (en) | Method and apparatus for service planning in a radio telephone system | |
| KR19990077626A (en) | Flexible channel allocation for a cellular system based on a hybrid of measurement-based dynamic channel assignment and reuse-distance criterion algorithm | |
| WO2003001742A1 (en) | Method and system for detection of and dynamic adaptation to radio interference in a shared wireless communications environment | |
| KR100430597B1 (en) | Cell control method and cell system | |
| WO1997024895B1 (en) | Method and apparatus for improved control over cellular systems | |
| CA2319796A1 (en) | Operator assisted tool and method for frequency plan revision within a cellular telephone system | |
| US6134442A (en) | Controlling operations in a cellular system using neighbor association-based cost values | |
| JP2001313977A (en) | Device and method for interference matrix relating to adaptive channel allocation in mobile telephone system | |
| EP0720402B1 (en) | Method for automatic creation of peripheral zone information | |
| CN100502589C (en) | Method and device for zone-cross switchover of mobile communication system | |
| KR20050054953A (en) | Method for operating a mobile radio telephone system, mobile radio telephone system, mobile station and device for determining a sub-group of adjacent radio cells in a mobile radio telephone system | |
| EP1153523B1 (en) | Methods and systems for controlling hard and soft handoffs in radio communication systems | |
| EP0744115B1 (en) | Method for determining handover in a communications system | |
| US6311067B1 (en) | Gradual frequency plan revision methodology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| FZDE | Discontinued | ||
| FZDE | Discontinued |
Effective date: 20021231 |