FR2853800A1 - Multi-mode mobile terminals wireless access managing method for cellular telecommunication network, executes queries transmitted by cellular network, where sequencing module sequences queries centrally - Google Patents

Abstract

The method involves deploying radio access technologies (TARs) for radio access networks (RANs), where some TARs are in an active state and others in a passive state. Set of queries transmitted by a cellular network, are executed by an execution module of the TAR, where chronology of execution are managed by a sequencing module. The queries are sequenced in a centralized way by the sequencing module of the active TARs. Independent claims are also included for the following: (a) a software architecture for wireless radio access of a multi-mode mobile terminal; (b) a multi-mode mobile terminal for supporting a number of distinct radio access networks.

Description

SOFTWARE ARCHITECTURE AND METHOD FOR RADIO ACCESS TO A MOBILE TERMINAL

MULTI-MODE

TECHNICAL AREA

  The invention relates to the field of telecommunications and relates more specifically to a method for managing the radio access of a multimode mobile terminal in a cellular telecommunications network in which a plurality of radio access technologies (TAR) are deployed. ) each corresponding to a specific radio access network (RAN), at least one of said TARs being in the active state in the mobile while the other TARs are in a passive state, each TAR comprising at least one module d execution of requests transmitted by the cellular network to said terminal and at least one sequencing module intended to manage the chronology of the execution of said requests.

  The invention also relates to a software architecture intended to implement the method and a terminal comprising said architecture.

  More specifically, the invention finds an application in multimode mobile terminals, that is to say, terminals capable of supporting several distinct radio access technologies. 25 STATE OF THE PRIOR ART Currently, the reference standard in mobile telephony in Europe is the GSM standard (for Global System for Mobile Telecommunications).

  In order to guarantee its evolution towards the third generation, international standardization bodies of SP 21786 HM proposed the standard UMTS (for Universal Mobile Telecommunications System) whose technical specifications are being developed within the 3GPP group (for Third 5 Generation Partnership Project) developed within the partnership called 3GPP. The aim of UMTS standardization is to guarantee full compatibility between UMTS mode and GSM mode.

  Dual-mode GSM / UMTS 10 mobile terminals are classified into four types: Type 1, Type 2, Type 3 and Type 4 which are distinguished by their behavior in the dual-mode context.

  When a Type 1 terminal in GSM mode (respectively in UMTS mode) is located in a GSM radio network or in a UTRA radio network, the radio part of this UTRA terminal (for Universal Terrestrial Radio Access) (respectively GSM) is "inactive" and does not perform any reception quality measurement. Switching from one mode to another can only be done with the intervention of the user.

  When a Type 2 terminal is connected to a GSM radio network (UMTS respectively), the inactive radio part of the terminal (UTRA respectively GSM) can take measurements in order to automatically switch to the network with the best reception quality .

  Type 3 terminals differ from those of Type 2 in that they also offer the possibility of receiving simultaneously in both modes. However, simultaneous transmission by in two modes is not possible. As with SP 21786 HM type 2 terminals, switching from one radio network to another takes place automatically.

  With Type 4 terminals, the transition from one radio network to another takes place automatically and one can receive and transmit simultaneously on both networks.

  Among the four types of terminals in this classification, type 2 dual-mode terminals will be the most widespread. These terminals 10 will allow operators to capitalize on current investments in GSM by taking advantage of existing coverage while familiarizing their subscribers with the new services brought by UMTS.

  The invention relates more specifically to type 2 terminals in which a single radio interface is used in the two modes (GSM and UMTS) to ensure the radio connection between the terminal and the network.

  To this end, three main layers of 20 radio protocols are described in the 3GPP standard for ensuring the radio interface of a mobile terminal with a RAN.

  These three layers are made up of - the physical layer or layer 1, the data link layer or layer 2, - the radio resource control layer (RRC) or layer 3.

  Layer 1 is divided into a physical sublayer PLi intended to execute tasks received asynchronously from the radio resource control layer 3 and a logical sublayer LL1 SP 21786 HM intended to generate a sequencing to allow the physical layer L1 to execute said tasks synchronously.

  FIG. 1 schematically illustrates the implementation of layer 1 in a dual-mode GSM / UMTS terminal.

  The logic sublayer LL1 is physically implemented in the central processing unit CPU (for Central Processing Unit) of the terminal while the physical layer L1 is implemented in a dedicated DSP (for Digital Signal Processing) circuit.

  In each operating mode of the terminal (GSM or UMTS), the logical sublayer LL1 receives asynchronously from layer 3, requests 15 for execution of tasks such as for example requests for measurements on cells neighboring the current cell ( active cell of the network) and generates a sequencing to synchronize the execution by the physical sublayer PLi of said tasks with the radio interface of the active RAN.

  A major problem with the architecture described above stems from the fact that it does not include any means for managing radio access conflicts between the two systems supported by the terminal, in particular in the context of dual-mode intersystem measurements.

  The object of the invention is to propose a software architecture of layer 1 and a method making it possible to improve the radio access of a multimode mobile terminal.

  SP 21786 HM PRESENTATION OF THE INVENTION The invention recommends a method for managing the radio access of a multimode mobile terminal in a cellular telecommunication network in which a plurality of distinct radio access technologies (TAR) are deployed. each corresponding to a specific radio access network (RAN), at least one of said TARs being in the active state in the mobile while the other TARs are in a passive state, each TAR 10 comprising at least one module d execution of requests transmitted by the cellular network to said terminal and at least one sequencing module intended to manage the chronology of the execution of said requests.

  According to the invention, the sequencing of said tasks is carried out centrally by the sequencing module of the active ART in the current cell.

  Preferably, before the execution of a task in a passive cell, - the passive sequencing module sends to the active sequencing module a request to perform a specific task, - on receipt of this request, the active sequencing module programs the execution of said task as a function of the tasks previously programmed by the active TAR and of the specific conditions of the passive TAR, and transmits to the sequencing module of the passive TAR a command to execute the specific task required.

  - The passive sequencing module transmits said command to the passive task execution module.

  SP 21786 HM The invention also relates to a software architecture for the radio access of a mobile multimode terminal in a cellular telecommunication network in which are deployed a plurality of distinct radio access technologies (TAR) each using a network of specific radio access (RAN), said architecture comprising a physical layer dedicated to the execution of tasks transmitted by the cellular network to said terminal in asynchronous requests and a logical layer dedicated to the sequencing of the execution of said requests.

  According to the invention, this architecture comprises a central sequencing module arranged in the logic layer of the active TAR.

  The architecture according to the invention comprises a first communication interface arranged between the logic layer of the active TAR and the logic layer of the passive TAR.

  In a preferred embodiment, the architecture according to the invention further comprises a second communication interface arranged between the physical layer of the active ART and the physical layer of the passive ART.

  The invention also relates to a mobile terminal 25, dual mode GSM / UMTS.

BRIEF DESCRIPTION OF THE DRAWINGS

  Other characteristics and advantages of the invention will emerge from the description which follows, taken by way of nonlimiting example, with reference to the appended figures in which: SP 21786 HM - Figure 1, described above, schematically illustrates the layer 1 of a conventional software architecture for managing the radio access of a dual-mode GSM / UMS mobile terminal, - Figure 2 schematically illustrates layer 1 of a software architecture for managing the radio access of a dual-mode mobile terminal GSM / UMS according to an exemplary embodiment of the invention, - Figure 3 schematically illustrates the 10 steps of a mode of the method according to the invention.

  DETAILED PRESENTATION OF PARTICULAR EMBODIMENTS

  The following description concerns access

  radio of a dual-mode GSM / UMTS mobile terminal camping on a UMTS cell for example and making measurements on neighboring GSM cells.

  FIG. 2 schematically illustrates two stacks of communication protocols corresponding respectively to the radio access technology TAR (RAT in English, for Radio Access Technology) GSM and UMTS. 20 TAR will activate the TAR used in the cell on which the mobile is camped and TAR inactivates the other TAR considered.

  Each of these two stacks comprises an RRC layer intended to manage the radio resources 25 comprising modules 2 intended to manage the signaling on the radio interface and to ensure secure transport of the signaling messages of the upper layers not shown, a sub- physical layer PLi comprising software modules 4 responsible for actually carrying out the measurements on the neighboring UMTS cells and a logical sublayer LL1 comprising SP 21786 HM software modules 6 responsible, inter alia, for sequencing the measurements, ie say to program them at certain times that depend on the other activities that the mobile must perform, on the priority of these measures.

  The requests relating to these measurements are transmitted asynchronously to the physical sublayer PL1 by the RRC layer. The logical sublayer LL1 of each protocol stack synchronizes the 10 asynchronous requests coming from the upper layers with the radio interface of the network.

  The coexistence in the mobile of two stacks of communication protocols, can generate a problem of synchronization of the tasks at the level of the 15 physical sublayers PLi. To avoid this problem, the method according to the invention assigns a different role to the logical sublayers LL1 of the two TARs which coexist in the terminal. To this end, a central measurement sequencer is defined in the logical sublayer LL1 20 of the active TAR which therefore becomes master responsible for the instants of each measurement to be carried out.

  The logical sublayer LL1 of the other passive TAR becomes a slave.

  If measurements are to be made on the slave TAR, the logical sub-layer LL1 of this TAR must request authorization from the master TAR and wait for the latter to allocate time intervals for carrying out these measurements. Then the slave TAR requests the physical sub-layer PLi associated with it to carry out the measurements in the time interval allowed.

  SP 21786 HM The communication between the two logical sublayers LL1 of the two TARs is carried out by means of a first communication interface 8 which makes it possible to interrupt with greater temporal precision 5 the radio link of the physical sublayer PLi of a TAR with the network to replace it with a radio link from the physical sublayer PLi of the other TAR.

  In an alternative embodiment, this precision is improved by a second interface 10 10 arranged between the physical sublayer PLi of the active TAR and the physical layer Li of the passive TAR.

  This interface 10 allows the respective physical sub-layers PLi of the active and passive TARs to exchange information relating to the progress of the processing operations affected by each of the two physical layers.

  In operation, the active logical sublayer LL1 manages the sequencing of all the tasks, both those which must be executed by the active physical sublayer PLi and those which must be executed by the passive physical layer Li.

  FIG. 3 schematically illustrates the method according to the invention.

  In this figure, blocks 12 and 14 respectively represent the active logical LL1 and the passive logical LL1, and blocks 16 and 18 respectively represent the active physical layer PLi and the passive physical layer PLi.

  SP 21786 HM In step 20, the layer the active LL1 sublayer transmits to the layer the passive LL1 sublayer state information specific to the active mode.

  In step 22, the passive LL1 sublayer 5 receives a measurement request from the upper layer RRC, analyzes this request, and transmits it to the layer the active LL1 sublayer (step 24).

  In step 26, the active LL1 sub-layer 10 establishes a sequencing which takes into account the current programming of the measurements which must be executed by the active PLI sublayer and stores (step 28) a sequencing of the measurements which must be executed by the active and passive PLI sublayers.

  In step 30, the active LL1 sublayer allocates to the active PLI sublayer the time intervals necessary to execute the measurements.

  In step 40, the active PLI sublayer performs the measurements, and transmits to the active LL1 sublayer 20 (step 42) a measurement report.

  In step 44, the active LL1 sublayer transmits to the passive LL1 sublayer the functions relating to the measurements programmed in the request received in step 24 and the sequencing of these measurements 25 carried out in step 26.

  In step 46, the passive LLI sublayer generates measurement commands and transmits these commands (step 48) to the passive PLI sublayer.

  In step 50, the passive PLI sublayer 30 sends a radio access request to the active Layer.

  SP 21786 HM On receipt of this request, the active PLi sub-layer authorizes (step 52) continuous access if the terminal is in standby mode or limited access to the time intervals defined in step 26, if the terminal is in active mode .

  In step 54, the passive PLi sublayer performs the measurements in accordance with the sequencing established by the active LL1 sublayer and transmits a measurement report to the passive LL1 sublayer (step 56).

SP 21786 HM

Claims (7)

  1. Method for managing the radio access of a multimode mobile terminal in a cellular telecommunications network in which a plurality of radio access technologies (TAR) are deployed, each corresponding to a radio access network (RAN) ) specific, at least one of said TARs being in the active state in the mobile while the other 10 TARs are in a passive state, each TAR comprising at least one module for executing requests transmitted by the cellular network to said terminal and at least one sequencing module intended to manage the chronology of the execution of said requests, a method characterized in that the sequencing of said tasks is carried out centrally by the sequencing module of the active TAR in the current cell.   2. Method according to claim 1, in which, before the execution of a task in a passive cell, the passive sequencing module sends a request to the active sequencing module to perform a specific task, - on receipt of this request , the active sequencing module schedules the execution of said task as a function of the tasks previously programmed by the active TAR and specific conditions of the passive TAR, and transmits a command to the sequencing module of SP 21786 HM the passive TAR execution of the specific task required, the passive TAR sequencing module transmits said command to the task execution module of the passive TAR.   3. Software architecture for radio access of a mobile multimode terminal in a cellular telecommunication network in which a plurality of distinct radio access technologies (TAR) are deployed, each using a specific radio access network (RAN) , said architecture comprising a physical sub-layer dedicated to the execution of tasks transmitted to the terminal in asynchronous requests and a logical sub-layer dedicated to the sequencing of the execution of said requests, architecture characterized in that it comprises a module sequencing center arranged in the logical sublayer of the active ART.   4. Architecture according to claim 3, characterized in that it comprises a first communication interface (8) arranged between the logical sublayer of the active TAR and the logical sublayer of the passive TAR.   5. Architecture according to claim 4, characterized in that it further comprises a second communication interface (10) arranged between the physical sublayer of the active ART and the physical sublayer of the passive ART.   SP 21786 HM 6. Multimode mobile terminal capable of supporting a plurality of separate radio access networks (RAN), characterized in that it comprises a software architecture according to one of claims 3 to 5.   7. GSM / UMTS dual-mode mobile terminal comprising a software architecture for managing communication with the radio interface of a cellular telecommunications network in which GSM radio access technologies and UMTS radio technology are deployed, one at less of said radio access technologies being in the active state in the current cell while the other radio access technology 15 is in a passive state, said architecture comprising a physical sublayer dedicated to the execution of transmitted tasks to the terminal by the cellular network via asynchronous requests and a logical sublayer dedicated to the sequencing of the execution of said tasks, terminal characterized in that it comprises a central sequencing module arranged in the logical sublayer of the technology radio access active in the current cell. SP 21786 HM