WO2010085985A1 - Procédé pour détecter des transferts de cellule inutiles dans un réseau de communication mobile - Google Patents

Procédé pour détecter des transferts de cellule inutiles dans un réseau de communication mobile Download PDF

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Publication number
WO2010085985A1
WO2010085985A1 PCT/EP2009/001536 EP2009001536W WO2010085985A1 WO 2010085985 A1 WO2010085985 A1 WO 2010085985A1 EP 2009001536 W EP2009001536 W EP 2009001536W WO 2010085985 A1 WO2010085985 A1 WO 2010085985A1
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WO
WIPO (PCT)
Prior art keywords
cell
change
identifier
registration
core network
Prior art date
Application number
PCT/EP2009/001536
Other languages
German (de)
English (en)
Inventor
Rémi KLEO
Original Assignee
Deutsche Telekom Ag
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Deutsche Telekom Ag filed Critical Deutsche Telekom Ag
Priority to ES09839066.9T priority Critical patent/ES2641768T3/es
Priority to PL09839066T priority patent/PL2392159T3/pl
Priority to EP09839066.9A priority patent/EP2392159B1/fr
Publication of WO2010085985A1 publication Critical patent/WO2010085985A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W8/00—Network data management
    • H04W8/02—Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
    • H04W8/04—Registration at HLR or HSS [Home Subscriber Server]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/34—Reselection control
    • H04W36/38—Reselection control by fixed network equipment

Definitions

  • the invention relates to a method for operating a cellular mobile radio network, wherein each cell of the mobile radio network has a unique identifier, and wherein the identifier of the current cell is temporarily stored on the network side to a currently registered in a cell mobile terminal.
  • Mobile networks allow users to use the services offered, in particular via different wireless technologies, such as 2G (GSM / GPRS / EDGE), 3G (UMTS / HSxPA) or LTE.
  • 2G GSM / GPRS / EDGE
  • 3G UMTS / HSxPA
  • LTE Long Term Evolution
  • the mobile networks are usually in radio network and "core network", i. the core network, divided.
  • the radio network provides for the radio coverage
  • the "core network” acts other functions of the network, such as the localization of the terminals, so that the customer can be reached at any time by initiating the so-called paging (broadcast within a network area comprising multiple cells) for so-called "Mobile Terminated Call", ie calls within a mobile network in which the called terminal is a mobile terminal.
  • Radio technologies (2G (GSM / GPRS / EDGE), 3G (UMTS / HSxPA) or LTE).
  • 2G GSM / GPRS / EDGE
  • 3G UMTS / HSxPA
  • LTE Long Term Evolution
  • the standards have defined various possibilities so that, depending on the quality of the radio coverage or the prioritization of the radio technologies, either the terminals automatically change from one cell to another and thereby send a request to the Core Net (eg area change procedure, so-called Routing Area Update) Procedure, abbreviated RAU) or, depending on the quality of the radio coverage or the prioritization of the radio technologies, the network forces the terminals to change from one cell to another (handover procedure).
  • Core Net eg area change procedure, so-called Routing Area Update) Procedure, abbreviated RAU
  • RAU Routing Area Update
  • the network forces the terminals to change from one cell to another (handover procedure).
  • the nodes of the core network are able to distinguish between switching within the node and switching to another node through the usual signaling that is exchanged during a cell change.
  • a terminal If a terminal is at the boundary between 2 or more cells or wireless technologies, it may be in an unstable state and often switch between the different cells or radio techniques: this problem can also be described as a ping-pong effect or carousel effect. This results in unnecessary or superfluous cell changes.
  • the object underlying the invention is to overcome these disadvantages and to provide a method which is suitable for detecting unstable cell change situations and thus for detecting unnecessary, superfluous cell changes in order to be able to prevent unnecessary cell changes if necessary.
  • each cell of the mobile network having a unique identifier, and wherein the identifier of the current cell is temporarily stored on the network side to a currently registered in a cell mobile terminal, it is that in addition at least the time of Registration is stored in the current cell, in particular, is temporarily stored.
  • the identifier of the cell n-1 used in the current cell n before the registration of the mobile radio terminal and the time t-1 of the registration in the previously used cell n-1 are additionally stored, in particular temporarily stored.
  • rejection is optional, initially such a change is detected on the network side as a superfluous change and counted.
  • the identification of the cell serving as the current cell (s) in the outgoing core network node ( ie in the old node) is stored in the storage register for the previous cell (n-1), and the values in the storage register for the current cell (s) are reinitialized after the source core network has been restored.
  • Node (ie, the old node) has received the message (for example, so-called Cancel Location when leaving the local area) from a central database, in particular HLR or HSS, that the change was successful.
  • the identifier of the new cell (n + 1) with the identifier of the previously used cell (n-1), which was sent from the terminal in the request for cell change (English: Routing Area Update Request or Location Area Update Request), compared and at a match of the identifiers (n + 1, n -1) takes place an evaluation of the times (t + 1, t-1) of the registration in the previous cell (n-1) and the future cell (n + 1), wherein when falling below a definable period of the change in the new cell (n + 1) is detected on the network side as a superfluous change.
  • the mobile network is divided into cells n. These cells are each grouped into a larger "group", so-called areas, which are usually referred to with different terms such as in particular Location Areas, Routing Areas, Service Area or Tracking Areas. These terms each designate an area that includes multiple cells of the cellular mobile network.
  • Each cell is identified with a unique identifier, the global identifier.
  • the global identifier (English: global cell id). This "Global Cell ID" contains the identifier of the cell and the group where this cell belongs.
  • the core network i. the so-called “Core Network” is the global identifier of the cell where the mobile station is registered.
  • the terminal remains silent for a given time and shows no activity, the current global cell tag is usually erased. If a request is sent to the network to reach the terminal or to send data to the terminal, then the core network must initiate a broadcast, a so-called paging procedure.
  • Radio network and the terminal When a terminal announces itself due to the quality of the radio coverage and / or the priority of the various radio technologies to change from one cell or cell group (for example, Location Area 1) to another cell or cell group (for example, Location Area 2) Radio network and the terminal the entire identifier of the cell, where the terminal wants to go to the "core network", ie the core network.
  • the radio network decides to force a terminal to change due to the quality of the radio coverage and / or the priority of the various radio techniques, the radio network and the terminal send the entire identifier of the cell where the terminal is to become the "Core Network".
  • the "Core Network” thus knows the global cell ID where the terminal wants or has to go.
  • the "Core Network Node" previously erases the old global cell identifier from its memory and stores the new identifier.
  • the invention thus consists, in particular, of storing, in addition to the global cell identifier n, the time t at which the storage took place.
  • the invention is applicable both when both cells are operated upon initiation of a cell change by the same core network node (intra-exchange), as well as when operating on cells of different core network nodes (interchange).
  • the global cell identifier n is due to a change update the location of the terminal, so according to the invention the last global cell identifier n and the time t of storage, which had been stored as the current identifier n, in another additional temporary memory as previous identifier n-1 with the associated time stamp t-1 stored before the new current cell identifier n + 1 is stored and thereby the older cell identifier n and the old time stamp t is overwritten by the new time stamp t + 1.
  • the global cell identifier n of the cell in which the terminal is currently registered
  • the time t-1 at which the previous global cell identifier n-1 was stored i. the time t-1 of registration in the previous cell n-1
  • the current cell treats the former cell and the next cell by two different "Core Network Nodes", ie manages and operates when a request is received in the "Core Network”, the global cell identifier n is due a change of the location of the terminal to update, so according to the invention, the last global cell identifier n and the time t of storage, which had been stored as the current identifier n, in another additional temporary memory as previous identifier n-1 with the associated time stamp t -1 is stored before the new current cell identifier n + 1 is stored, thereby overwriting the older cell identifier n and the old time stamp t by the new time stamp t + 1.
  • the global cell identifier n of the cell in which the terminal was last registered in this node which can be interpreted as a previous cell.
  • the invention uses the above information to provide a redundant, i. unnecessary change of the cell in which the terminal is registered, i. is registered to recognize.
  • the radio network When a terminal announces itself due to the quality of the radio coverage to change from one cell n to another cell n + 1, the radio network sends the entire identifier of the cell n + 1 where the terminal wants to go.
  • the radio network decides to command the terminal to change from the current cell n to another cell n + 1, the radio network sends the entire identifier of the cell n + 1 where the terminal should go the core network.
  • the "Core Network” node compares according to the invention the global cell identifier n-1, where the terminal was previously registered, and the cell identifier n + 1, where the terminal is to be registered, in particular in the case where the cell with the identifier n + 1 and n-1 are handled by the same "Core Network” node.
  • the invention is also applicable when the cell n, where the terminal was last registered, and the cell n + 1, where the terminal is to be registered, is assigned to two different core network nodes, ie in the event that the terminal of a Cell assigned to another "Core Network” node should switch to this "Core Network” node.
  • a corresponding message is generated on the network side in order to prevent an immediate re-triggering of a change procedure
  • the identifier of a cell n, n + 1 comprises a cell identification and an area identification.
  • cell change covers both the change from one cell n to another cell n + 1 of the same radio technology, as well as the change from one cell n of a first radio technology to another cell n + 1 of another radio technology.
  • the data on the network side rejected changes comprising at least the identifiers of the cells (n, n + 1) and / or the identifier of the mobile station are stored on the network side for further processing.
  • the "core network” can thus conduct a statistic, ie store such data and thereby both count the unnecessary cell changes and store data of the affected customer and terminals in order to allow the operator the most affected customers and / or cells and / or Identify terminal types.
  • Figure 1 shows an unstable state with multiple switching between two cells within a core network node
  • FIG. 2 shows an unstable state with multiple changes between two cells of two different core network nodes
  • FIG. 3 is a flow chart of a first embodiment of the method according to the invention.
  • Figure 4 is a flowchart of a second embodiment of the method according to the invention.
  • FIGS. 1 and 2 unstable states are shown, as a result of which a repeated cell change of a registered mobile radio terminal takes place from a first cell 1 into a second cell 2 and vice versa within the mobile radio system.
  • the first cell 1 is operated by a first core network node 10 (core network 10) and the second cell 2 is operated by a second core network node 20 (core network 20), ie the cells 1, 2 in various core networks 10, 20 are involved.
  • both the first cell 1 and the second cell 2 are operated by a single core network node 30 (core network 30), ie, the cells 1, 2 are integrated into the same core network node 30 here are and are managed by this.
  • the cell identification 1 and the time t1 of this first registration are detected.
  • the fields for the previous registration are not yet occupied in this case, since the logging in of the terminal takes place for the first time, for example after switching on the device.
  • a cell change 11 is triggered from the first cell 1 to another cell 2.
  • the identifier 2 of this cell and the time t2 of the registration are stored in this cell 2.
  • the core network node 10 has the data of the previously used cell 1 and the time t1 of the earlier registration and the target cell 1 and further the time t3 of registration in this cell 1vor.
  • a cell change 11 is triggered from the first cell 1 to another cell 2.
  • the identifier 2 of this cell and the time t2 of the registration are stored in this cell 2.
  • the core network has the data of the previously used cell 1 and the time t1 of the earlier registration in cell 1 and, furthermore, the data of the cell currently used cell 2 at time t2 of registration in this cell 2 before and the next cell 1 at time t3.
  • the identifiers and time stamps of the registration of the mobile radio terminal are present in the current, current cell as well as in the previously used cell.
  • the core network nodes (ie the core network) additionally store, at least temporarily, the time t at which the global cell identifier n is stored during the registration of the terminal.
  • the core network nodes store the previous global cell identifier n-1 and the time stamp t-1 at which the cell identifier n-1 was registered and stored so that the current cell identifier n and the former cell identifier n-1 are stored. 1 available to the Core Network.
  • a parameter is defined in the core network node, which specifies how long after a change a change from one cell and back to the same cell is detected as before, and thus counted and treated as superfluous.
  • the "core network" nodes compare the current time t + 1 with the time t (in case of switching between two different nodes) or (t-1) in case of a change within the same node to which the terminal was previously registered and which has been stored, and if the difference ⁇ t between the two time stamps t-1, t + 1 or less than the timer, the cell change is detected as unnecessary.
  • n identifier of the current cell n + 1 identifier of the cell to be changed to; t-1 time (time stamp) of the registration in the previous cell n-1; t time (timestamp) of the registration in the current cell n; t + 1 time of request of change to the next cell n + 1
  • the core network ie the core network nodes, have detected a superfluous request for a cell switch, the core network nodes deny the requested cell switch and send a dedicated reason (reject cause) that can be interpreted accordingly by the terminal and the wireless network a new request for the same cell change does not take place immediately thereafter.
  • the "core network nodes" preferably store the customer data, the terminal identifier, the cell identifier and all other information that is necessary for later processing / evaluation of the unnecessary cell changes to improve the quality of the wireless network and the services offered.
  • FIG. 3 shows a flowchart of an embodiment of the method according to the invention for detecting unstable states in the event that the terminal is represented within the same core network node.
  • the identification of the current cell n is stored in step 110 and the time stamp t of the registration of the mobile radio terminal in the current cell n is stored in the next step 120.
  • the registration of the mobile station in the current cell n is the moment of the booking of the mobile station in this cell of the mobile network meant, respectively the time t of the change in the current cell n.
  • the core network on the part of the mobile station or on the part of the radio network receives a request 130 to change to another cell n + 1 within the network, it is checked whether data of a previous cell n-1 are present. However, this is only the case if the mobile station was previously registered in another cell n-1 before registration in the current cell n.
  • Step 150 cached the identifier of the current cell n and the time of registration t in this current cell n and determined that it is an ordinary handover process, ie, an ordinary handover procedure 160, which is performed accordingly.
  • a next step 170 it is now checked whether the identifier of the target cell n + 1 matches the identifier of the previous cell n-1. This is done in the next step 180. If the target cell n + 1 and the previous cell n-1 are not identical to each other, then it is an ordinary switching procedure which is triggered and performed in the next step 190.
  • a predeterminable time threshold is exceeded, then it is an ordinary change process that is triggered and carried out in a next step 210 since enough time has elapsed since the previous registration.
  • a redundant change procedure 220 is detected and a change to the cell n + 1 that with the preceding cell n -1 can be prevented. If such a superfluous cell change 220 is detected, an initial step is taken in an intermediate step 230, which allows a further evaluation: at least one counter is incremented.
  • step 240 further data such as, for example, the identifier of the target cell n + 1 and the identifier of the source cell n as well as the corresponding time stamp of the registrations for further optional evaluations 250 can be detected and stored.
  • the identification of an unstable state by detecting a superfluous cell change allows the deposition of a corresponding denial message 270, which can be evaluated by the radio network and / or the mobile station accordingly, so that a further request not triggered immediately following the network-side denial of the cell change again becomes.
  • step 260 if the operator of the "Core Network" node has so desired by configuration. "Should a denial of the needless cell change request not be desired, then the" Core Network "node becomes Initiate and perform an ordinary switching procedure in the next step 261.
  • FIG. 4 shows a flow diagram of a further embodiment of the method according to the invention for detecting unstable states in the event that the terminal is to switch between two different "core network" nodes.
  • the core network on the part of the mobile station or on the part of the radio network receives a request 330 to change to another cell n + 1 within the network but from another "core network" node, it is checked whether data of a previous cell n are present , However, if the mobile station was registered for the first time in the current cell n, for example because the terminal has never been registered in this "core network" node, then after checking 340, whether the data of the previous cell n is present and it is detected in that this is not the case, in step 350 the identifier of the future cell as well as the time of the registration t have been temporarily stored in this current cell n and it is determined that this is an ordinary switching process, ie an ordinary switching procedure 360, which is carried out accordingly ,
  • the mobile radio terminal in front of the current cell n had already been registered in a previous cell n, the identifier of the previous cell n and the time t of the registration were buffered in this previous cell and are now available for evaluation.
  • a next step 370 it is now checked whether the identifier of the target cell n + 1 matches the identifier of the previous cell n. This is done in the next step 380. If the target cell n + 1 and the previous cell n are not identical to one another, then this is an ordinary change procedure that is triggered and executed in the next step 390.
  • a predeterminable time threshold is exceeded, then it is an ordinary change process that is triggered and carried out in a next step 410, since enough time has elapsed since the previous registration.
  • step 440 further data such as, for example, the identifier of the target cell n + 1 and the identifier of the source cell n as well as the corresponding time stamp of the registrations for further optional evaluations 450 can be detected and stored.
  • the identification of an unstable state by determining a superfluous cell change allows discontinuation of a corresponding refusal message 470, which can be evaluated by the radio network and / or the mobile station accordingly, so that a further request is not triggered again immediately following the network refusal of the cell change becomes.
  • step 460 if the operator of the "core network” node has not wished to do so, and refusing to deny the needless cell change request becomes the "core network” node initiate and perform an ordinary switching procedure in the next step 461.

Abstract

La présente invention concerne un procédé pour faire fonctionner un réseau de communication mobile cellulaire, chaque cellule (n) du réseau de communication mobile présentant un identifiant univoque (n), et l'identifiant de la cellule courante (n) pour un terminal de communication mobile inscrit couramment dans une cellule, étant enregistré temporairement côté réseau. En outre, au moins l'instant (t) d'inscription dans la cellule courante (n) est enregistré, en particulier temporairement, afin notamment de détecter côté réseau des transferts de cellule inutiles.
PCT/EP2009/001536 2009-01-29 2009-03-04 Procédé pour détecter des transferts de cellule inutiles dans un réseau de communication mobile WO2010085985A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
ES09839066.9T ES2641768T3 (es) 2009-01-29 2009-03-04 Procedimiento para el reconocimiento de cambios de célula innecesarias en una red de telefonía móvil
PL09839066T PL2392159T3 (pl) 2009-01-29 2009-03-04 Sposób rozpoznawania niepotrzebnej zmiany komórki w mobilnej radiowej sieci komórkowej
EP09839066.9A EP2392159B1 (fr) 2009-01-29 2009-03-04 Procédé pour détecter des transferts de cellule inutiles dans un réseau de communication mobile

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
PCT/EP2009/000565 WO2010085974A1 (fr) 2009-01-29 2009-01-29 Procédé pour détecter des transferts intercellulaires inutiles dans un réseau de communication mobile
EPPCT/EP2009/000565 2009-01-29

Publications (1)

Publication Number Publication Date
WO2010085985A1 true WO2010085985A1 (fr) 2010-08-05

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Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/EP2009/000565 WO2010085974A1 (fr) 2009-01-29 2009-01-29 Procédé pour détecter des transferts intercellulaires inutiles dans un réseau de communication mobile
PCT/EP2009/001536 WO2010085985A1 (fr) 2009-01-29 2009-03-04 Procédé pour détecter des transferts de cellule inutiles dans un réseau de communication mobile

Family Applications Before (1)

Application Number Title Priority Date Filing Date
PCT/EP2009/000565 WO2010085974A1 (fr) 2009-01-29 2009-01-29 Procédé pour détecter des transferts intercellulaires inutiles dans un réseau de communication mobile

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ES (1) ES2641768T3 (fr)
WO (2) WO2010085974A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998052375A2 (fr) * 1997-05-13 1998-11-19 Nokia Networks Oy Procede de passage
EP0969685A2 (fr) * 1998-07-02 2000-01-05 Nec Corporation Méthode de contrôle de données d'abonnés dans un réseau de communication mobile
WO2001052589A1 (fr) * 2000-01-10 2001-07-19 Qualcomm Incorporated Procede permettant de realiser un enregistrement de niveau ressources radio dans un systeme de communication sans fil

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998052375A2 (fr) * 1997-05-13 1998-11-19 Nokia Networks Oy Procede de passage
EP0969685A2 (fr) * 1998-07-02 2000-01-05 Nec Corporation Méthode de contrôle de données d'abonnés dans un réseau de communication mobile
WO2001052589A1 (fr) * 2000-01-10 2001-07-19 Qualcomm Incorporated Procede permettant de realiser un enregistrement de niveau ressources radio dans un systeme de communication sans fil

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Publication number Publication date
WO2010085974A1 (fr) 2010-08-05
ES2641768T3 (es) 2017-11-13

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