Patent Publication Number: US-2006009187-A1

Title: Multi-mode interoperable mobile station communications architectures and methods

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      The present application is a continuation of commonly assigned U.S. patent application Ser. No. 10/228,484 filed on 27 Aug. 2002 with like title, from which the benefits under 35 U.S.C. 120 are claimed, the contents of which are hereby incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE  
      The present disclosure relates generally to wireless mobile station communications, and more particularly to wireless mobile station communication architectures with multi-mode interoperability, for example, communications supporting time division multiple access (TDMA) based and spread spectrum based modes of operation, wireless devices having multi-mode architectures and methods therefor.  
     BACKGROUND  
      Wireless cellular communication mobile stations with multi-service interoperability will enable communications in areas served by different communications protocols, otherwise referred to herein as a heterogeneous communications environments.  
      The initial deployment of new communications technologies is characterized typically by limited areas of new technology service in contiguous regions served by legacy technologies. In many countries, for example, the W-CDMA implementation of Universal Mobile Telecommunications Services (UMTS) will be deployed initially on isolated islands of service in a sea served by existing Groupe Special Mobile services (GSM)/Generalized Packet Radio Services (GPRS) network infrastructure.  
      UMTS services will not be offered over substantial contiguous areas until new technology infrastructure is installed or until existing infrastructure is upgraded, but this will require substantial capital outlays by telecommunications services providers and may not be complete for some time, resulting in a heterogeneous communications environment in many geographic regions for the foreseeable future.  
      Multi-mode cellular handsets capable of operating in areas served by emerging and legacy communications infrastructures will provide users earlier access to the emerging communications technology and hasten its deployment. Multi-mode wireless communications devices are also desirable for communications in other heterogeneous environments.  
      Mobile wireless communications devices will require architectures with multi-mode interoperability for seamless operation in heterogeneous communications environments.  
      The various aspects, features and advantages of the present disclosure will become more fully apparent to those having ordinary skill in the art upon careful consideration of the following Detailed Description with the accompanying drawings described below. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an exemplary communications coverage area served by two different communications protocols.  
       FIG. 2  is an exemplary multi-mode mobile station communications architecture.  
       FIG. 3  is a more detailed schematic of an exemplary multi-mode mobile station architecture for GSM and W-CDMA communications.  
       FIG. 4  is an exemplary radio resource coordinator module for multi-mode communication architectures.  
       FIG. 5  is an exemplary mobility management component for multi-mode communication architectures.  
       FIG. 6  is an exemplary data router configuration.  
       FIG. 7  is another exemplary data router configuration.  
       FIG. 8  is another exemplary data router configuration. 
    
    
     DETAILED DESCRIPTION  
       FIG. 1  is an exemplary heterogeneous communications environment  100  comprising a relatively contiguous GSM/GPRS coverage area  110  and several isolated W-CDMA coverage areas  120  and  122 . The heterogeneous environment of  FIG. 1  is typical of the early stages of deployment of advanced communications network infrastructure, e.g., a W-CDMA network, in area where an existing infrastructure, e.g., GSM/GPRS, is already well established. The exemplary environment  100  is not limited to one served by the exemplary radio access networks, but may be served more generally by a heterogeneous network comprising any radio access technologies, for example, one comprising 3 rd  and 4 th  generation communications service and beyond.  
      For multi-mode wireless communications devices operating in heterogeneous networks, for example a mobile terminal following user route  130  in  FIG. 1 , it is desirable for the communications devices to simultaneously monitor cells of the different radio access networks in idle and active modes to perform cell selection and handover procedures, including the bi-directional handoff of radio access bearer services, for example in networks comprising GSM Base Station Subsystems (BSS) and Universal Terrestrial Radio Access Network (UTRAN) access networks.  
       FIG. 2  is an exemplary multi-mode mobile wireless communications device architecture  200  comprising generally an application layer  210  interfaced with a services layer  220  interfaced with a multi-mode layer  230 , comprising at least two interoperable radio access technologies, interfaced with a hardware layer  240 .  
      In  FIG. 2 , the application layer  200 , at the top of the model, comprises generally one or more application subsystems. In the exemplary architecture  300  of  FIG. 3 , the application layer  310  includes a single application subsystem comprising an AT command parser  312 , an application manager  314 , and, for example, Synergy applications. The application layer may also include generally other application subsystems, for example a Java Virtual Machine and its corresponding applications, among other application subsystems.  
      In  FIG. 3 , the exemplary services layer  320  comprises a Data Flow Service Provider (DFSP)  322 , a Data Session Service Provider (DSSP)  324 , and Connection Management (CM) components  326 . The application layer interfaces with the services layers and communications therebetween are performed by function calls, for example Application Utility Functions (AUF). Communications also occur within the application and services layers, for example, between the DFSP  324  and the DSSP  324 .  
      The multi-mode layer comprises generally an interoperability entity that interconnects the radio access technologies. In  FIG. 2 , the first radio access technology  232  is a GSM/GPRS radio access technology, which may include an extension, for example EDGE or EDGE Classic. The second radio access technology  234  is a non-GSM technology, for example Wideband Code Division Multiple Access (W-CDMA) Universal Mobile Telecommunications Services (UMTS) radio access technology.  
      In  FIG. 2 , the multi-mode layer, or engine layer, comprises generally a common subsystem  236  comprising components shared among the different radio access technologies, for example mobility management layer, data router, connectivity components, etc. The engine layer also includes a time critical functionality control component  238 , which is shared among the radio access technologies, for example for measurement control, scheduling, cell selection, etc. as discussed more fully below.  
      In the exemplary architecture of  FIG. 3 , the components shared by the first and second radio access technologies include the application layer  310  and the services layer  320 . In one embodiment, several components of the multi-mode layer  330  are also shared by the radio access technologies, including the mobility management component  332 , the Session Management (SM) component  334 , the Radio Link Protocol (RLP) component  336 , and other components discussed further below. In  FIG. 3 , a Digital Signal Processing (DSP) component  350  includes generally modulation and demodulation functionality for the corresponding radio access technologies, WCDMA and GSM/GPRS in the exemplary embodiment.  
      In the exemplary embodiment of  FIG. 3 , the architecture includes a radio resource layer  338  for transitioning between the first and second radio access technologies. In this exemplary embodiment, the radio resource layer is shared by the radio access technologies.  
       FIG. 4  is a more detailed illustration of the radio resource layer  400  comprising a radio resource component  402  including a state transition component  410  and first and second state machines  420  and  430  for the corresponding radio access technologies. Other state machines may be included for embodiments that include additional radio access technologies. The state transition component  410  generally allocates resources among the first and second radio access technologies. The state transition component also maintains current state information while transitioning from one state machine to the other to enable returning to the current state if the transition is unsuccessful.  
      In the exemplary embodiment of  FIG. 4 , the first state machine  420  is coupled generally to a W-CDMA radio resource entity (RRC)  440 , which includes a W-CDMA message parser  442 , a message builder  444 , and a layer configuration controller  446 , among other known functionality elements. The second state machine  430  is coupled to the GPRS radio resource (GRR)/GSM radio resource (RR) entity  450 , which includes a GSM/GPRS message parser  452 , a message builder  454 , and a configuration controller  456 , among other known elements. The radio resource entities  440  and  450  and corresponding elements are specific to the radio access technologies in the device.  
      In  FIG. 3 , the radio resource layer  338  communicates radio resource status and other control information, for example registration area and NAS system information, PLMN availability, etc., to a mobility management layer, and in the exemplary embodiment to a mobility management component  332  thereof, the functionality of which is discussed more fully below.  
      In  FIG. 3 , a timing component  340  is coupled to the radio resource layer  338 . The exemplary timing component  340  is divided into a real-time task processing portion  342 , and an interrupt-processing portion  344 . The real-time task portion is coupled to corresponding portions of the radio access technologies for performing real-time processing, and the interrupt-processing portion is coupled to the radio access technologies for performing interrupt processing.  
      Time critical radio access technology functionality, for example, Public Land Mobile Network (PLMN) selection, cell selection and reselection, signal measurement, handover, etc., is coordinated by a real-time coordinator  343  in the real-time portion of the timing component. The real-time coordinator reports status and other information to the radio resource layer  338 , and the real-time coordinator controls switching between radio access technologies under control from the radio resource component  337 .  
      For example, during initial cell selection the radio resource component  337  controls cell selection on the appropriate radio access technology, for example GSM or W-CDMA in the exemplary embodiment, commands power measurement and channel synchronization, commands to read system information scheduled by Radio Resource (RR) component, and follows cell selection procedure to camp on the most suitable cell. After finding a cell to camp on, the radio resource component sends an indication to RR/RRC. If no cells are found suitable on the desired radio access technology, cell selection procedure on the other radio access technology is selected. If no suitable cells are found, an available PLMN list is sent to radio resource component.  
      The timing component also controls interrupt processing, for example medium access control (MAC) functionality of the first and second radio access technologies. The W-CDMA Layer 1/MAC interruption service routine (ISR) functionality includes, for example, DSP timing, transport to logical and vice verse channel mapping, etc. The timing component also controls interrupt processing for the GSM/GPRS Layer 1 MAC ISR, for example Adaptive Gain Control (AGC), Adaptive Frequency Control (AFC), waveform generation, MAC procedures, etc.  
      Interrupt processing information is communicated from each Layer 1 MAC ISR to the corresponding radio link control (RLC) components  346  and  348  of the first and second radio access technologies and to a DSP  350  via an Micro Controller Unit (MCU)/DSP interface  352  common to both radio access technologies.  
       FIG. 5  is an exemplary mobility management task layer  500  comprising a mobility management component  510  coupled a GPRS Mobility Management (GMM), element  520  and to a Mobility Management (MM) element  530 . The GMM and MM components include functionality blocks specific to the integrated radio access technology, for example registration, de-registration and location management, authentication, message building and parsing, etc.  
      The mobility management layer interfaces with the radio resource layer  540 , the radio access technology L1-task layer  550 , the GSM Logical Link Control (LLC) entity  560 , the Session Management (SM) entity  570 , the MMICM  580 , and the DSSP  590 . These interfaces are also illustrated generally in  FIG. 3 . The mobility management layer also interfaces with and provides radio access technology status information to the data router as discussed below.  
      In the exemplary embodiment of  FIG. 3 , a data router  360  is coupled to the services layer  320 , and particularly to the data flow service provider (DFSP)  322  thereof by a bi-direction data bus. The data router  360  is also coupled to the first and second radio access technologies, and in the exemplary embodiment to a W-CDMA Packet Data Communications Protocol (PDCP)  362  and to a GSM Sub Network Dependent Communications Protocol (SNDCP)  364 .  
      The data router  360  generally routes data between the services layer  320  and one of the radio access technologies. In  FIG. 3 , the radio resource component  338  is coupled to the data router  360  by the mobility management module  332 , which provides control information to the data router for selecting one of the radio access technologies. In  FIG. 6 , the data router  600  is configured for routing data from the DFSP  610  to the PDCP  620  for W-CDMA radio access technology (RAT). In  FIG. 7 , the data router  700  is configured for null mode, as occurs when the radio access technology is undefined, and  FIG. 8  illustrates the data router  800  configured for routing data from the DFSP  810  to the SNDCP  820  for GSM radio access technology.  
      While the present disclosure and what is considered presently to be the best mode thereof have been described in a manner that establishes possession thereof by the inventors and that enables those of ordinary skill in the art to make and use the same, it will be understood and appreciated that there are many equivalents to the exemplary embodiments disclosed herein and that myriad modifications and variations may be made thereto without departing from the scope and spirit thereof, which are to be limited not by the exemplary embodiments but by the appended claims.