JP5650764B2 - Assisted state transition of user equipment (UE) for delay sensitive applications within a wireless communication system - Google Patents

Description

Priority Claims under 35 USC 119 This patent application is assigned to the ASSISTED filed on February 17, 2010, each assigned to the assignee of this application and expressly incorporated herein by reference. US Patent Provisional Application No. 61 / 305,364 entitled `` STATE TRANSITION OF A USER EQUIPMENT (UE) FOR DELAY SENSITIVE APPLICATIONS WITHIN A WIRELESS COMMUNICATIONS SYSTEM '' and `` ASSISTED STATE TRANSITIONS OF A USER '' filed on February 5, 2010 US Provisional Application No. 61 / 301,919, entitled “EQUIPMENT WITHIN A WIRELESS COMMUNICATIONS SYSTEM”.

Reference to co-pending patent applications This patent application is assigned to the `` MANAGING DEDICATED CHANNEL RESOURCE ALLOCATION TO USER '' filed on February 5, 2010, each assigned to the assignee of this application and specifically incorporated herein by reference. Co-pending U.S. Patent Application No. 61 / 301,929 entitled `` EQUIPMENT BASED ON RADIO BEARER TRAFFIC WITHIN A WIRELESS COMMUNICATIONS SYSTEM '', `` SELECTIVE ALLOCATION OF DEDICATED CHANNEL (DCH) RESOURCES WITHIN A WIRELESS COMMUNICATIONS '' US Provisional Patent Application No. 61 / 297,963, named SYSTEM, and TRANSITIONING A USER EQUIPMENT (UE) TO A DEDICATED CHANNEL STATE DURING SETUP OF A COMMUNICATION SESSION DURING A WIRELESS filed on May 17, 2010 Relates to co-pending US Patent Application No. 12 / 781,666 entitled “COMMUNICATIONS SYSTEM”.

  Embodiments relate to assisted state transition of user equipment (UE) for delay-sensitive applications in a wireless communication system.

  Wireless communication systems include first generation analog wireless telephone service (1G), second generation (2G) digital wireless telephone service (including provisional 2.5G and 2.75G networks), and third generation (3G) high-speed data / Internet It has evolved through various generations, including supported wireless services. Currently, many different types of wireless communication systems are in use, including cellular systems and personal communications service (PCS) systems. Examples of known cellular systems include Cellular Analog Advanced Mobile Phone System (AMPS), Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), TDMA Global System There are digital cellular systems based on the For Mobile Connection (GSM®) variant, and newer hybrid digital communication systems that use both TDMA and CDMA technologies.

  A method for providing CDMA mobile communications is referred to herein as IS-95, a TIA / EIA / IS-95-A entitled “Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System”. In the United States by the Telecommunications Industry Association / Electronic Industry Association. The combined AMPS & CDMA system is described in TIA / EIA standard IS-98. Other communication systems include IMT-2000 / UM, or international mobile telecommunications system 2000 /, targeting broadband CDMA (W-CDMA), CDMA2000 (e.g. CDMA2000 1xEV-DO standard, etc.) or TD-SCDMA. It is described in the universal mobile communication system standard.

  In a W-CDMA wireless communication system, user equipment (UE) is a fixed location Node B (cell site or cell) that supports communication links or services in a specific geographic region adjacent to or around the base station. (Also called). Node B is a packet data network that uses a standard Internet Engineering Task Force (IETF) -based protocol that generally supports methods for differentiating traffic based on quality of service (QoS) requirements. Provide entry points to the radio access network (RAN). Thus, Node B typically interacts with the UE via the over-the-air interface and with the RAN via Internet Protocol (IP) network data packets.

  In wireless telecommunications systems, push-to-talk (PTT) functionality is prevalent in the service sector and consumers. PTT may support “dispatch” voice services that operate over standard commercial wireless infrastructures such as W-CDMA, CDMA, FDMA, TDMA, GSM, etc. In the dispatch model, communication between endpoints (eg, UEs) occurs within a virtual group, and one “speaker” voice is transmitted to one or more “listeners”. A single instance of this type of communication is usually referred to as a dispatch call, or simply a PTT call. A PTT call is a group instantiation that defines call characteristics. A group is essentially defined by a member list and related information, such as a group name or group identification information.

  In an embodiment, the application server sends a call message configured to request the start of a communication session to be arbitrated by the application server between the originating UE and the at least one target UE. ). In response to the call message, the application server selectively transmits dummy data to the serving access network of the given UE to facilitate the transition to the dedicated channel state of the given UE associated with the communication session. For example, the application server can selectively send dummy data based on the size of the call message and / or the type of communication session.

  BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the embodiments of the present invention and the attendant advantages thereof, reference is made to the following detailed description and accompanying drawings that are presented by way of illustration only and not to limit the invention. If it is better understood by considering it together, it will be easily obtained.

FIG. 2 illustrates a wireless network architecture that supports user equipment and a radio access network in accordance with at least one embodiment of the invention. FIG. 2 is a diagram illustrating the core network of FIG. 1 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of the wireless communication system of FIG. 1 in more detail. FIG. 6 illustrates an example of user equipment according to at least one embodiment of the invention. FIG. 6 illustrates a state determination process performed at an application server in a wireless communication system. FIG. 4B is an exemplary implementation of a portion of the process of FIG. 4A, in accordance with an embodiment of the present invention. FIG. 4B is an exemplary implementation of a portion of the process of FIG. 4A, in accordance with an embodiment of the present invention. FIG. 4B is an exemplary implementation of another portion of the process of FIG. 4A, in accordance with an embodiment of the present invention. FIG. 4B is an exemplary implementation of another portion of the process of FIG. 4A, in accordance with an embodiment of the present invention. FIG. 4B is an exemplary implementation of a portion of the process of FIG. 4A, in accordance with an embodiment of the present invention. FIG. 4D shows an alternative implementation of the process of FIG. 4F according to another embodiment of the invention. FIG. 4B illustrates another exemplary implementation of a portion of the process of FIG. 4A, according to an embodiment of the invention.

  Aspects of the invention are disclosed in the following description and related drawings directed to specific embodiments of the invention. Alternate embodiments may be devised without departing from the scope of the invention. Furthermore, well-known elements of the invention will not be described in detail or will be omitted so as not to obscure the relevant details of the invention.

  The terms “exemplary” and / or “example” are used herein to mean “serving as an example, instance, or illustration”. Any embodiment described herein as "exemplary" and / or "example" is not necessarily to be construed as preferred or advantageous over other embodiments. Similarly, the term “embodiments of the present invention” does not require that all embodiments of the present invention include the discussed features, advantages or modes of operation.

  Moreover, many embodiments are described in terms of a series of operations to be performed by, for example, elements of a computing device. The various operations described herein can be performed by particular circuits (e.g., application specific integrated circuits (ASICs)), by program instructions executed by one or more processors, or a combination of both. Be recognized. Further, these sequences of operations described herein can be performed in any form of computer-readable storage medium that stores a corresponding set of computer instructions that, when executed, cause an associated processor to perform the functions described herein. It can be considered that it is completely embodied. Thus, various aspects of the invention may be embodied in a number of different forms that are all intended to fall within the scope of the claimed subject matter. Further, for each embodiment described herein, the corresponding form of any such embodiment is described herein as, for example, "logic configured to" perform the described operations. There is.

  A high data rate (HDR) subscriber station, referred to herein as user equipment (UE), may be mobile or fixed and may communicate with one or more access points (APs), which may be referred to as Node Bs. it can. The UE transmits and receives data packets to and from a radio network controller (RNC) via one or more of the Node Bs. Node B and RNC are parts of a network called a radio access network (RAN). The radio access network can transport voice and data packets between multiple UEs.

  The radio access network may be further connected to additional networks external to the radio access network, such core networks may include certain carrier-related servers and devices, as well as corporate intranets, the Internet, public switched telephone networks (PSTN), Serving General Packet Radio Service (GPRS) Support Node (SGSN), Gateway GPRS Support Node (GGSN), etc., including connections to other networks, such as voice and Data packets can be transported. A UE that has established an active traffic channel connection with one or more Node Bs can be referred to as an active UE and can be referred to as being in a traffic state. A UE that is in the process of establishing an active traffic channel (TCH) connection with one or more Node Bs may be referred to as being in a connection setup state. A UE may be any data device that communicates through a wireless channel or a wired channel. The UE may further be any of several types of devices including, but not limited to, a PC card, a CompactFlash device, an external or internal modem, or a wireless or wired phone. . The communication link through which the UE sends signals to Node B is referred to as the uplink channel (eg, reverse traffic channel, control channel, access channel, etc.). The communication link through which Node B sends signals to the UE is referred to as the downlink channel (eg, paging channel, control channel, broadcast channel, forward traffic channel, etc.). As used herein, the term traffic channel (TCH) may refer to either an uplink / reverse or downlink / forward traffic channel.

  FIG. 1 shows a block diagram of an exemplary embodiment of a wireless communication system 100 in accordance with at least one embodiment of the invention. System 100 can connect access terminal 102 to network equipment that provides a data connection between a packet-switched data network (eg, an intranet, the Internet, and / or core network 126) and UEs 102, 108, 110, 112. A UE such as a mobile phone 102 communicating with an access network or radio access network (RAN) 120 via an air interface 104 may be included. As shown herein, the UE may be a pager 110, shown as a separate computer platform 112 with a mobile phone 102, a personal digital assistant 108, here a two-way text pager, and even a wireless communication portal. Thus, embodiments of the present invention include, but are not limited to, a wireless communication portal, including, but not limited to, a wireless modem, a PCMCIA card, a personal computer, a telephone, or any combination or partial combination thereof, or a wireless communication function It can be realized in any form of access terminal having Further, as used herein, the term “UE” in other communication protocols (ie, other than W-CDMA) is interchangeably referred to as “access terminal”, “AT”, “wireless device”, “client device”. ”,“ Mobile terminal ”,“ mobile station ”, and variants thereof.

  Referring again to FIG. 1, the interrelationship between the components of the wireless communication system 100 and the elements of the exemplary embodiments of the present invention are not limited to the illustrated configuration. System 100 is only an example, and remote UEs, such as wireless client computing devices 102, 108, 110, 112, can be wirelessly between and / or not limited to, core network 126, Internet, PSTN, Any system that allows communication between components connected via air interface 104 and RAN 120 may be included, including SGSN, GGSN, and / or other remote servers.

  The RAN 120 controls messages sent to the RNC 122 (generally sent as data packets). The RNC 122 is responsible for signaling, establishing, and tearing down the bearer channel (ie, data channel) between the serving general packet radio service (GPRS) support node (SGSN) and the UE 102/108/110/112. If link layer encryption is possible, the RNC 122 encrypts the content before transferring the content via the air interface 104. The functionality of RNC 122 is well known in the art and will not be described further for the sake of brevity. Core network 126 may communicate with RNC 122 over a network, the Internet, and / or the public switched telephone network (PSTN). Alternatively, the RNC 122 can connect directly to the Internet or an external network. In general, the network or Internet connection between the core network 126 and the RNC 122 transfers data, and the PSTN transfers voice information. The RNC 122 can be connected to a plurality of Node Bs 124. In a manner similar to core network 126, RNC 122 is typically connected to Node B 124 by a network, the Internet, and / or the PSTN for data transfer and / or voice information transfer. Node B 124 may broadcast the data message wirelessly to a UE, such as mobile phone 102, for example. As is known in the art, Node B 124, RNC 122, and other components may form RAN 120. However, alternative configurations may be used and the invention is not limited to the configuration shown. For example, in another embodiment, the functionality of one or more of RNC 122 and Node B 124 can be reduced to a single “hybrid” module that has the functionality of both RNC 122 and Node B 124.

  FIG. 2A shows a core network 126 according to one embodiment of the invention. In particular, FIG. 2A shows the components of a general packet radio service (GPRS) core network implemented in a W-CDMA system. In the embodiment of FIG. 2A, the core network 126 includes a serving GPRS support node (SGSN) 160, a gateway GPRS support node (GGSN) 165, and the Internet 175. However, it should be understood that in alternative embodiments, the Internet 175 and / or some of the other components may be located outside of the core network.

  In general, GPRS is a protocol used by Global System for Mobile communications (GSM) telephones to transmit Internet Protocol (IP) packets. The GPRS core network (eg, GGSN 165 and one or more SGSN 160) is the central part of the GPRS system and also supports W-CDMA based 3G networks. The GPRS core network is an integral part of the GSM® core network and provides mobility management, session management, and transport of IP packet services in GSM® and W-CDMA networks.

  The GPRS Tunneling Protocol (GTP) is a limited IP protocol for the GPRS core network. GTP is a protocol that allows GSM® or W-CDMA network end users (for example, access terminals) to move around from one location to the Internet while staying connected to the Internet. is there. This is accomplished by transferring the subscriber's data from the subscriber's current SSGN 160 to the GGSN 165 that is processing the subscriber's session.

  Three forms of GTP are used by the GPRS core network: (i) GTP-U, (ii) GTP-C, and (iii) GTP ′ (GTP Prime). GTP-U is used to transfer user data in a tunnel separated for each packet data protocol (PDP) context. GTP-C is used for control signaling (eg, PDP context setup and deletion, GSN reachability verification, updates or changes when a subscriber moves from one SGSN to another, etc.). GTP ′ is used for transferring charging data from the GSN to the charging function.

  Referring to FIG. 2A, the GGSN 165 serves as an interface between the GPRS backbone network (not shown) and the external packet data network 175. The GGSN 165 extracts packet data in the associated packet data protocol (PDP) format (eg, IP or PPP) from the GPRS incoming packet coming from the SGSN 160 and transmits the packet over the corresponding packet data network. In the other direction, the incoming data packet is directed by the GGSN 165 to the SGSN 160, which manages and controls the radio access bearer (RAB) of the destination UE served by the RAN 120. Thereby, GGSN 165 stores the current SGSN address of the target UE and the profile of the user in its location register (eg, in the PDP context). The GGSN serves as an IP address assignment and is the default router for connected UEs. The GGSN also performs authentication and billing functions.

  In one example, SGSN 160 is representative of one of many SGSNs in core network 126. Each SGSN serves to deliver data packets from and to the UE within the associated geographic service area. SGSN 160 tasks include packet routing and forwarding, mobility management (eg, connection / disconnection and location management), logical link management, and authentication and charging functions. The SGSN location register contains location information (e.g. current cell, current VLR, etc.) and user profiles of all GPRS users registered in SGSN 160 (e.g. IMSI, PDP address etc. used in packet data network) Are stored in one or more PDP contexts for each user or UE, for example. Therefore, SGSN has (i) reverse tunneling of downlink GTP packets from GGSN 165, (ii) uplink tunnel of IP packets in the direction of GGSN 165, and (iii) mobility management when UE moves between SGSN service areas. Execute, (iv) play the role of mobile subscriber billing. As will be appreciated by those skilled in the art, in addition to (i)-(iv), the SGSN configured for the GSM / EDGE network is slightly different compared to the SGSN configured for the W-CDMA network. Has different functions.

  The RAN 120 (or UTRAN or the like in the Universal Mobile Telecommunications System (UMTS) system architecture) communicates with the SGSN 160 via the Iu interface via a transmission protocol such as Frame Relay or IP. SGSN160 is an IP-based interface between SGSN160 and other SGSNs (not shown) and internal GGSN, and GTP protocols defined above (e.g. GTP-U, GTP-C, GTP ', etc.) Communicate with GGSN165 via Gn interface using. Although not shown in FIG. 2A, the Gn interface is also used by the Domain Name System (DNS). The GGSN 165 is connected to a public data network (PDN) (not shown) and then to the Internet 175 either directly via a Gi interface according to the IP protocol or via a wireless application protocol (WAP) gateway.

  A PDP context is a data structure that exists in both SGSN 160 and GGSN 165 that contains communication session information for a particular UE when the UE has an active GPRS session. When a UE wishes to initiate a GPRS communication session, it must first connect to SGSN 160 and then activate a PDP context with GGSN 165. This allocates a PDP context data structure at the SGSN 160 that the subscriber is currently visiting and at the GGSN 165 serving the access point of the UE.

  FIG. 2B shows an example of the wireless communication system 100 of FIG. 1 in more detail. In particular, referring to FIG. 2B, UE1... N are shown as connecting to RAN 120 at locations served by different packet data network endpoints. The example of FIG. 2B is specific to the W-CDMA system and terminology, but it will be understood how FIG. 2B can be modified to fit a 1xEV-DO system. Thus, UE1 and UE3 are to RAN 120 in the portion served by the first packet data network endpoint 162 (e.g. may correspond to SGSN, GGSN, PDSN, home agent (HA), foreign agent (FA), etc.) Connecting. The first packet data network endpoint 162 then passes through the routing unit 188 to the Internet 175 and / or authentication, authorization and accounting (AAA) server 182, provisioning server 184, Internet protocol (IP) multimedia. Connect to one or more of a subsystem (IMS) / session initiation protocol (SIP) registration server 186 and / or an application server 170. UE2 and UE5... N connect to RAN 120 at the portion served by second packet data network endpoint 164 (which may correspond to, for example, SGSN, GGSN, PDSN, FA, HA, etc.). Similar to the first packet data network endpoint 162, the second packet data network endpoint 164 then passes through the routing unit 188 to the Internet 175 and / or AAA server 182, provisioning server 184, IMS / Connect to one or more of SIP registration server 186 and / or application server 170. The UE 4 can connect directly to the Internet 175 and then connect to any of the system components described above via the Internet 175.

  Referring to FIG. 2B, UE1, UE3, and UE5... N are shown as wireless mobile phones, UE2 is shown as a wireless tablet PC, and UE4 is shown as a wired desktop station. However, in other embodiments, the wireless communication system 100 can connect to any type of UE, and the example shown in FIG. 2B may not limit the types of UEs that may be implemented in the system. It will be understood. Also, although AAA 182, provisioning server 184, IMS / SIP registration server 186, and application server 170 are each shown as structurally separate servers, in at least one embodiment of the present invention, of these servers, One or more of the may be integrated.

  2B, the application server 170 is shown as including a plurality of media control complexes (MCC) 1 ... N170B and a plurality of regional dispatchers 1 ... N170A. Collectively, regional dispatchers 170A and MCC 170B, in at least one embodiment, communicate communication sessions within wireless communication system 100 (e.g., half-duplex group communication sessions via IP unicast protocol and / or IP multicast protocol). It is included in an application server 170 that can correspond to a distributed network of servers that collectively function to mediate. For example, a communication session arbitrated by the application server 170 can theoretically occur between UEs located somewhere in the system 100, so as to reduce the latency of the arbitrated communication session (e.g., in North America Multiple regional dispatchers 170A and MCCs are distributed (so that the MCC does not relay media between session participants in China). Thus, with reference to the application server 170, it will be appreciated that related functions may be performed by one or more of the regional dispatchers 170A and / or one or more of the MCCs 170B. Regional dispatcher 170A is generally responsible for any functions related to establishing a communication session (e.g., handling of signaling messages between UEs, scheduling and / or sending of notification messages), and MCC 170B is busy Serves to host the communication session between call instances, including signaling, the actual exchange of media during the arbitrated communication session.

  Referring to FIG. 3, a UE 200 (here, a wireless device), such as a mobile phone, has a platform 202, which is transmitted from the RAN 120 and ultimately a core network 126, the Internet, and / or other Software applications, data, and / or commands that can come from remote servers and networks can be received and executed. The platform 202 can include a transceiver 206 operably coupled to an application specific integrated circuit (“ASIC” 208) or other processor, microprocessor, logic circuit, or other data processing device. The ASIC 208 or other processor executes an application programming interface (“API”) 210 layer that interfaces with any resident program in the memory 212 of the wireless device. The memory 212 may be comprised of read only or random access memory (RAM and ROM), EEPROM, flash card, or any memory common to computer platforms. The platform 202 may also include a local database 214 that can hold applications that are not heavily used in the memory 212. The local database 214 is typically a flash memory cell, but may be any secondary storage device known in the art, such as magnetic media, EEPROM, optical media, tape, software, or hard disk. it can. Internal platform 202 components are operable with external devices such as antenna 222, display 224, push-to-talk button 228, and keypad 226, among other components, as is known in the art. May be combined.

  Thus, one embodiment of the invention can include a UE that includes the ability to perform the functions described herein. As those skilled in the art will appreciate, the various logic elements are incorporated into individual elements, software modules executing on the processor, or any combination of software and hardware to perform the functions disclosed herein. be able to. For example, the ASIC 208, the memory 212, the API 210, and the local database 214 can all be used cooperatively to load, store, and execute the various functions disclosed herein, and thus The logic circuit that performs the function may be distributed over various elements. Instead, the functionality can be integrated into one individual part. Accordingly, the features of UE 200 in FIG. 3 are considered merely illustrative and the invention is not limited to the illustrated features or configurations.

  Wireless communication between UE102 or UE200 and RAN120, for example, code division multiple access (CDMA), W-CDMA, time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple (OFDM), It may be based on different technologies such as Global System for Mobile Communications (GSM), or other protocols that may be used in a wireless or data communication network. For example, in W-CDMA, data communication is generally between client device 102, Node B 124, and RNC 122. The RNC 122 can connect to multiple data networks, such as the core network 126, PSTN, Internet, virtual private network, SGSN, GGSN, and thus the UE 102 or UE 200 can access a wider communication network. As described above and known in the art, voice transmissions and / or data can be transmitted from the RAN to the UE using various networks and configurations. Accordingly, the examples provided herein are not intended to limit embodiments of the present invention, but merely to help explain aspects of embodiments of the present invention.

  In the following, embodiments of the present invention will be generally described according to the W-CDMA protocol and related terms (e.g., UE instead of mobile station (MS), mobile unit (MU), access terminal (AT), etc.). RNC, EV-DO unlike BSC, EV-DO BS or MPT / BS, Node B, etc.). However, it will be readily understood by those skilled in the art how embodiments of the present invention can be applied in connection with wireless communication protocols other than W-CDMA.

  Traditional server arbitrated communication sessions (for example, half-duplex protocol, full-duplex protocol, VoIP, group session over IP unicast, group session over IP multicast, push-to-talk (PTT) session, push-to-transfer (PTX) session The session or call originator sends a request to the application server 170 to initiate a communication session, which then sends the call notification to one or more targets of the call. Forward the message to RAN120.

  The user equipment (UE) can be in either an idle mode or a radio resource control (RRC) connection mode in a universal mobile communication service (UMTS) terrestrial radio access network (UTRAN) (eg, RAN 120).

Based on UE mobility and activity, while in RRC connected mode, the RAN 120 can instruct the UE to transition between several RRC sub-states, namely CELL_PCH, URA_PCH, CELL_FACH, and CELL_DCH states. Can be characterized as follows:
In the CELL_DCH state, in the uplink and downlink, the UE is allocated a dedicated physical channel, the UE is recognized at the cell level by its current active set, and the UE is dedicated transport channel, downlink and uplink (TDD) Shared transport channels are allocated and combinations of these transport channels can be used by the UE.
In CELL_FACH state, the UE is not allocated a dedicated physical channel, the UE continuously monitors the forward access channel (FACH), and the UE is the default common or shared transport channel in the uplink (e.g., channel Is assigned a random access channel (RACH), which is a contention based channel with a power ramp-up procedure to adjust the transmit power, and the UE can transmit according to the access procedure of that transport channel, May be recognized by the RAN 120 at the cell level by the cell in which the UE last performed a previous cell update, and in TDD mode, one or more USCH or DSCH transport channels may be established.
In CELL_PCH state, no dedicated physical channel is allocated to the UE, the UE selects the PCH in the algorithm, monitors the PCH selected via the associated PICH using DRX, and no uplink activity And the location of the UE is recognized by the RAN 120 at the cell level by the cell in which the UE last performed a cell update in the CELL_FACH state.
In the URA_PCH state, no dedicated physical channel is allocated to the UE, and the UE selects the PCH in the algorithm, monitors the PCH selected via the associated PICH using DRX, and does not allow uplink activity The UE location is recognized by the RAN 120 at the registration area level by the UTRAN registration area (URA) assigned to the UE during the last URA update in the CELL_FACH state.

  Thus, the URA_PCH state (or CELL_PCH state) corresponds to a dormant state where the UE periodically wakes up and checks the paging indicator channel (PICH) and, if necessary, the associated downlink paging channel (PCH) For events of cell reselection, periodic cell update, uplink data transmission, paging response, re-entry into service area, the UE can enter the CELL_FACH state and send a cell update message. In the CELL_FACH state, the UE can send a message on the random access channel (RACH) and monitor the forward access channel (FACH). The FACH carries downlink communication from the RAN 120 and is mapped to the secondary common control physical channel (S-CCPCH). From the CELL_FACH state, the UE may enter the CELL_DCH state after a traffic channel (TCH) is obtained based on messaging in the CELL_FACH state. A table showing the mapping from the conventional dedicated traffic channel (DTCH) to the transport channel in the radio resource control (RRC) connection mode is shown in Table 1 as follows.

The notations (rel. 8) and (rel. 7) indicate the relevant 3GPP release, and the indicated channel has been introduced for monitoring or access.

  Communication sessions arbitrated by application server 170 may be associated with delay sensitive or high priority applications and / or services in at least one embodiment. For example, the application server 170 may correspond to a PTT server in at least one embodiment, and key criteria in a PTT session are fast session setup and a given level of quality of service (QoS) throughout the session. It will be understood that it is to maintain.

  As described above, in RRC connected mode, a given UE can operate on either CELL_DCH or CELL_FACH to exchange data with the RAN 120, whereby the given UE can operate on the application server 170. Can reach. As described above, in the CELL_DCH state, the uplink / downlink radio bearer consumes dedicated physical channel resources (eg, UL DCH, DL DCH, E-DCH, F-DPCH, HS-DPCCH, etc.). Some of these resources are also consumed for the operation of the high speed shared channel (ie HSDPA). In the CELL_FACH state, the uplink / downlink radio bearer is mapped to the common transport channel (RACH / FACH). Thereby, no dedicated physical channel resources are consumed in the CELL_FACH state.

  Traditionally, the RAN 120 is based on CELL_FACH and CELL_DCH based on the amount of traffic measured by the RAN 120 (e.g., the serving RNC 122 of the RAN 120) or reported from a given UE itself in one or more measurement reports. Migrate a given UE between Specifically, conventionally, the RAN 120 determines that the associated traffic volume of the UE, measured and / or reported on the uplink, or measured and / or reported on the downlink, transitions to the CELL_DCH state. Thus, a particular UE may be configured to transition from the CELL_FACH state to the CELL_DCH state when greater than one or more of the event 4a thresholds used by the RAN 120.

  Conventionally, when the originating UE sends a call request message to the application server 170 to start a communication session, the originating UE performs a cell update procedure, after which the originating UE enters the CELL_FACH state. Transition to one of the CELL_DCH states. When the originating UE transitions to the CELL_FACH state, the originating UE can transmit a call request message to the RAN 120 in RACH. When the originating UE transitions to the CELL_DCH state, the originating UE can transmit a call request message to the RAN 120 using the reverse link DCH or E-DCH. Call request messages are generally relatively small in size and are typically expected not to exceed the event 4a threshold used by the RAN 120 in determining whether to move the originating UE to the CELL_DCH state.

  In the CELL_FACH state, the originating UE can start sending the call request message sooner (e.g., it is not necessary to establish a radio link (RL) between the serving Node B and the serving RNC in the RAN 120, DCH resources are not consumed by the originating UE, eg, it is not necessary to perform the L1 synchronization procedure between the originating UE and the serving Node B). However, RACH is generally associated with lower data rates compared to DCH or E-DCH. Thus, while it may be possible to start sending a call request message at an earlier point in time, sending a call request message on RACH may in some cases be similar to that on DCH or E-DCH. Compared to transmission, it can take longer to complete. Therefore, it is generally more efficient for the originating UE to transmit more traffic volume on DCH or E-DCH compared to RACH, but a few messages cause overhead due to DCH configuration And can be transmitted relatively efficiently on RACH.

  As stated above, the state of the originating UE (eg, CELL_DCH or CELL_FACH) is determined based on the amount of uplink data that will be transmitted by the originating UE. For example, the standard defines an event 4a threshold for triggering traffic volume measurement (TVM) reporting. The event 4a threshold is defined in the standard and used by the UE to trigger a traffic volume measurement report, which aggregates the buffer occupancy of each uplink radio bearer.

  Other parameters not defined in the standard are the uplink event 4a threshold to cause a state transition to the CELL_DCH state for a given UE and the downlink event 4a to cause a state transition to the CELL_DCH state for a given UE. It is a threshold value. As will be appreciated, the uplink event 4a threshold and the downlink event 4a threshold are “not defined” in the standard, meaning that each threshold may vary by vendor or by implementation on different RANs. Means.

  Referring to the uplink event 4a threshold, in the CELL_FACH state, if the reported uplink buffer occupancy of each radio bearer exceeds the uplink event 4a threshold, the RNC 122 moves the UE to CELL_DCH. In an example, this determination may be made based on aggregated buffer occupancy or individual radio bearer buffer occupancy. If the aggregate buffer occupancy is used to determine the transition to CELL_DCH, the same threshold as that for triggering TVM can be used. Similarly, regarding the downlink event 4a threshold, in the CELL_FACH state, if the downlink buffer occupancy of the UE's radio bearer exceeds the downlink event 4a threshold, the RNC 122 moves the UE to the CELL_DCH state. In an example, this determination may be made based on aggregated buffer occupancy or individual radio bearer buffer occupancy.

  Thus, the size of the call request message may determine whether the originating UE transitions to CELL_FACH state or CELL_DCH state. Specifically, conventionally, one of the event 4a thresholds is used in the RAN 120 to determine the CELL_DCH state. Therefore, when the event 4a threshold is exceeded, the RAN 120 causes the UE to transition to the CELL_DCH state.

  However, the processing speed or responsiveness of the RAN 120 itself can also affect whether the CELL_DCH state or the CELL_FACH state is a more efficient option for sending a call request message. For example, if the RAN 120 can allocate DCH resources to the originating UE within 10 milliseconds (ms) after receiving the cell update message, the transition of the originating UE to the CELL_DCH state is affected by the delay. The transition to DCH may be suitable for sending easy call request messages, and may be relatively fast. On the other hand, if the RAN 120 can allocate a DCH resource to the originating UE after only 100 milliseconds (ms) after receiving the cell update message, the transition to the CELL_DCH state of the originating UE may be relatively slow. Therefore, the transmission of the call request message can be completed sooner if it is actually transmitted by RACH.

  As can be seen, event 4a thresholds are usually more efficient because lower D4 resources are more frequently allocated to UEs that do not necessarily require DCH to complete data exchange in a timely manner. Set high enough to achieve efficient resource utilization. However, it is possible that data transmissions that do not exceed the event 4a threshold can be transmitted more quickly in either the CELL_FACH state or the CELL_DCH state, based on the processing speed of the RAN 120 and the amount of data to be transmitted. However, as stated above, traditional RANs use criteria other than whether the amount of measured or reported traffic exceeds the event 4a threshold when determining the transition to the CELL_DCH state. Do not evaluate.

  W-CDMA Rel.6 introduces a new mechanism called traffic volume indicator (TVI), which allows the calling UE to choose to include the TVI in the cell update message during the cell update procedure. did it. RAN 120 sets the TVI as if it exceeded the event 4a threshold to trigger TVM reporting (i.e., as if the uplink traffic volume buffer occupancy exceeded the event 4a threshold to trigger TVM reporting). Since the cell update message (ie, TVI = true) is interpreted, the RAN 120 directly moves the originating UE to the CELL_DCH state. Alternatively, when the TVI is not included in the cell update message, the RAN 120 shifts the originating UE to the CELL_DCH state only when receiving the traffic volume measurement report of the event 4a.

  Thus, embodiments of the present invention are directed to state transitions assisted by an application server, which allows the application server to selectively send dummy packets to a given UE (eg, originating UE, target UE, etc.). Send. In one example, the application server 170 sets the size of the dummy packet to be equal to or greater than the downlink event 4a threshold so that the RAN 120 is prompted to transition to the CELL_DCH state of a given UE. Thus, the application server 170 can control whether the RAN 120 transitions the given UE to CELL_DCH based on whether the application server 170 sends a dummy packet to the given UE.

  In the following, FIGS. 4A to 4H illustrate a UE state transition process assisted by an application server according to an embodiment of the present invention, where the system 100 is a universal mobile using wideband code division multiple access (W-CDMA). Corresponds to communication system (UMTS). However, one of ordinary skill in the art will understand how FIGS. 4A-4H can be directed to communication sessions with protocols other than W-CDMA. In addition, some signaling messages referred to herein will be described in which application server 170 corresponds to a PTT server. However, it will be appreciated that other embodiments may be directed to servers that provide services other than PTT to the UEs of system 100 (e.g., push-to-transfer (PTX) services, VoIP services, group-text sessions, etc.). .

  FIG. 4A is a diagram illustrating a process of state determination performed at application server 170 in a wireless communication system. Referring to FIG. 4A, assume that application server 170 receives a call request message from a UE attempting to initiate a communication session (eg, a PTT communication session, etc.) (400A). Next, the application server 170 determines whether or not to prompt the originating UE to transition to the CELL_DCH state (405A). In one example, the determination of 405A may be automatic so that application server 170 always determines to prompt the originating UE to transition to the CELL_DCH state upon receiving a call request message. In another example, the determination of 405A may be based on whether application server 170 predicts that the originating UE is already in the CELL_DCH state. For example, the application server 170 can evaluate the size of the call request message, and if the size of the call request message is greater than the uplink event 4a threshold, the application server 170 is based on the uplink traffic volume of the cell request message. Thus, it is estimated that the RAN 120 has already shifted the originating UE to the CELL_DCH state, and thereby determines that the transition to the CELL_DCH is not prompted in the 405A. Alternatively, if the size of the call request message is not greater than the uplink event 4a threshold, the application server 170 has not yet transitioned the originating UE to CELL_DCH state based on the uplink traffic volume of the cell request message Thus, it is determined that the transition to CELL_DCH is promoted in 405A. In a further example, in addition to the size of the call request message, the application server 170 can also consider the UE's roaming state when determining whether the UE is expected to be in the CELL_DCH state. For example, if the UE is in a roaming network with a message size smaller than a threshold (assuming that the application server 170 knows such), the application server 170 has not yet transitioned to CELL_DCH I guess.

  Referring to 405A in FIG. 4A, in another example, the decision by the application server 170 as to whether the originating UE should transition to the CELL_DCH state is the “type” of the communication session (eg, VoIP, PTX, PTT, etc.) May be based on For example, the application server 170 can compare the determined communication session type with a given list of session types to determine whether the originating UE should transition to the CELL_DCH state at 405A. . In one example, if the comparison result indicates that the determined type is on a given list, the application server 170 determines that the session type is to prompt the originating UE to transition to the CELL_DCH state. A given list can be established. In this case, a given list of session types may correspond to relatively delay sensitive communication sessions, such as PTT or PTX sessions. Alternatively, if the comparison results indicate that the determined type is on the given list, the application server 170 avoids prompting the originating UE to transition to the CELL_DCH state. A list may be established. In this case, a given list of session types may correspond to communication sessions that are not particularly sensitive to delay, such as traditional call sessions or VoIP sessions.

  Referring to FIG. 4A, in 405A, when the application server 170 determines to prompt the originating UE to transition to the CELL_DCH state, the application server 170 transmits a call request ACK to the originating UE along with the dummy packet ( 410A). In an example, the dummy packet transmitted at 410A is configured to have at least a size equal to the downlink event 4a threshold so that the RAN 120 is prompted to transition the originating UE to the CELL_DCH state. Further, in 405A, when the application server 170 determines not to prompt the caller UE to enter the CELL_DCH state, the application server 170 transmits a call request ACK to the caller UE without a dummy packet ( 415A).

  The application server 170 further determines whether to prompt at least one target UE to transition to the CELL_DCH state (420A). As will be appreciated, although shown as sequential blocks in FIG. 4A, the determinations of 405A and 420A may be performed simultaneously. In one example, the determination of 420A may be automatic so that application server 170 always determines during the call setup that it prompts the transition of at least one target UE to the CELL_DCH state. In another example, the determination of 420A may be that application server 170 determines that at least one target UE is transitioned to CELL_DCH state by RAN 120 during call setup based on an associated notification message, even if there are no dummy packets. May be based on whether or not expected. For example, the application server 170 can evaluate the size of a notification message sent to at least one target UE at 420A, and the size of the notification message is used by the RAN to determine the transition to CELL_DCH. If it is greater than the downlink event 4a threshold, the application server 170 assumes that the RAN 120 will transition at least one target UE to the CELL_DCH state based on the downlink traffic volume of the announcement message, thereby In 420A, it is determined not to prompt the transition to CELL_DCH. Alternatively, if the size of the notification message sent to the at least one target UE is smaller than the downlink event 4a threshold, the application server 170 may determine that the RAN 120 is at least one based on the downlink traffic volume of the notification message. It is assumed that there is no plan to shift the target UE to the CELL_DCH state, and thereby, it is decided to prompt the transition to CELL_DCH at 420A.

  Referring to 420A in FIG. 4A, in another example, the decision by the application server 170 as to whether to move at least one target UE to the CELL_DCH state depends on the “type” of the communication session (e.g., VoIP, PTX, PTT Etc.). For example, the application server 170 may compare the determined communication session type with a given list of session types to determine whether at least one target UE should transition to the CELL_DCH state at 420A. Can do. In one example, if the comparison result indicates that the determined type is on a given list, the application server 170 determines to prompt the transition of at least one target UE to the CELL_DCH state so that A given list of types can be established. In this case, a given list of session types may correspond to relatively delay sensitive communication sessions, such as PTT or PTX sessions. Alternatively, if the comparison result indicates that the determined type is on a given list, the application server 170 avoids prompting the transition of at least one target UE to CELL_DCH state. A given list may be established. In this case, a given list of session types may correspond to communication sessions that are not particularly sensitive to delay, such as traditional call sessions or VoIP sessions.

  Referring to FIG. 4A, if the application server 170 determines that at 420A prompts the transition of at least one target UE to the CELL_DCH state, the application server 170 determines the location of at least one target UE associated with the call request message. The notification message is transmitted to the at least one target UE together with the dummy packet (425A). In an example, the dummy packet transmitted at 425A is configured to have at least a size equal to the downlink event 4a threshold so that the RAN 120 is prompted to transition at least one target UE to the CELL_DCH state. Also, if the application server 170 decides not to prompt the originating UE to transition to the CELL_DCH state at 420A, the application server 170 determines the location of at least one target UE associated with the call request message and accompanies a dummy packet. Without sending a notification message to at least one target UE (eg, if the notification message itself already exceeds the downlink event 4a threshold) (430A).

  FIG. 4B shows an exemplary implementation of a portion of the process of FIG. 4A, according to an embodiment of the invention. Specifically, FIG. 4B shows an example of the process of FIG. 4A for the originating UE, which originates in a CELL_URA or CELL_PCH state.

  Referring to FIG. 4B, a given UE (“originating UE”) is operating in either URA_PCH or CELL_PCH state (400B), and the originating UE is in the communication session arbitrated by the application server 170. RACH in a call request message for receiving a request to initiate (e.g., a user of a given UE pressing the PTT button) (408B) and the originating UE initiates a communication session in CELL_FACH state Assume that the transmission at 412B is determined.

  In 412B, after deciding to transmit a call request message from the originating UE in RACH in the CELL_FACH state, the originating UE will not allow the RAN 120 to transition the originating UE to the CELL_DCH state, and the cell update message without the TVI (416B). Therefore, the originating UE sends a cell update message without TVI to the RAN 120 with RACH (420B), and the RAN 120 sends a cell update confirmation message with FACH instructing the originating UE to transition to the CELL_FACH state. To respond to the cell update message. As those skilled in the art will appreciate, a transition from the URA_PCH or CELL_PCH state to the CELL_FACH state does not require a radio link (RL) established between the serving Node B and the serving RNC in the RAN 120, so 424B cell update The confirmation message may be sent relatively early compared to a cell update message that instructs the UE to transition to the CELL_DCH state.

  The originating UE receives the cell update confirmation message of 424B and transitions to the CELL_FACH state (428B). Conventionally, when a cell update confirmation message is received from the RAN 120, the originating UE responds with a cell update confirmation response message, after which the originating UE is allowed to transmit data to the RAN 120 via RACH. However, in the embodiment of FIG. 4B, the originating UE and RAN 120 are configured to allow the originating UE to transmit data before the cell update acknowledgment message is transmitted. An example of how the calling UE and RAN 120 may be configured to facilitate this type of “early” data transmission on RACH, which is incorporated herein by reference in its entirety, May 22, 2009 No. 61 / 180,640, US Patent Application Serial No. 091948, entitled “TRANSMITTING A REQUEST TO INITIATE A COMMUNICATION SESSION WITHIN A WIRELESS COMMUNICATIONS SYSTEM”. As will be appreciated, data can be transmitted earlier by sending a call request message before the cell update acknowledgment message, but this is not necessarily an essential feature in each embodiment of the invention. .

  Thus, before the cell update acknowledgment message is sent to RAN 120 in RACH, the originating UE sends a given number of call request messages to RAN 120 in RACH (432B). For example, the calling UE can repeat the call request message at a given interval until at least the call request message is acknowledged by the application server 170, so the first to Nth (N ≧ 1) call requests A message may be sent at 432B. The RAN 120 receives at least one of these call request messages and forwards the call request message to the application server 170 (eg, as in 400A of FIG. 4A) (436B). Upon receiving the call request message and determining the location of the associated call target, the application server 170 announces the communication session to each call target (440B). Since FIG. 4B focuses on the transition to the selective CELL_DCH state of the originating UE rather than the target UE, the logic of any such decision regarding the transition of the target UE to the selective CELL_DCH state is straightforward. Thus, it is omitted in FIG. 4B and will be discussed in more detail in other embodiments of the present invention.

  In 432B, after transmitting the call request message 1... N, the originating UE transmits a cell update confirmation response message to the RAN 120 by RACH (444B). As mentioned above, the cell update acknowledgment message transmission traditionally occurs prior to the transmission of data on RACH, but the originating UE and RAN 120 in particular in the embodiment of FIG. Configured to allow transmission of “early” data.

  Returning to the application server 170, after decoding the call request message from 436B, the application server 170 transmits a call request ACK to the RAN 120 for transmission to the originating UE (448B). The RAN 120 receives the call request ACK from the application server 170, and transmits the call request ACK to the originating UE via FACH (452B). Although the call request ACK is shown as occurring after the announcement message is sent at 440B, in other embodiments of the invention, the call request ACK may be sent at the same time or before the announcement message. I want you to understand.

  As will be appreciated by those skilled in the art, the application server 170 generally does not recognize whether the originating UE is connected to the RAN 120 in the CELL_FACH state or to the RAN 120 in the CELL_DCH state. However, in order to improve performance and reliability during a communication session, the application server 170 generally desires to maintain the originating UE in the CELL_DCH state. Accordingly, in one embodiment of the present invention, application server 170 determines whether to prompt the originating UE to transition to CELL_DCH state at 456B (eg, as at 405A in FIG. 4A). For example, the application server 170 can evaluate the size of the call request message received at 436B to infer whether the originating UE is expected to be already operating in the CELL_DCH state, If the threshold does not exceed the threshold, it can be determined that the originating UE transitions to the CELL_DCH state. Alternatively, the determination of 456B may determine that the originating UE transitions to the CELL_DCH state whenever a call request message is received, regardless of the size of the call request message. In a further example, in addition to the size of the call request message, the application server 170 can also consider the UE's roaming state when determining whether the UE is expected to be in the CELL_DCH state. For example, if the UE is in a roaming network with a message size smaller than a threshold (assuming that the application server 170 knows such), the application server 170 has not yet transitioned to CELL_DCH I guess. In a further example, the application server 170 can evaluate the call type of the communication session to determine whether to prompt the originating UE to transition to the CELL_DCH state at 456B.

  In the embodiment of FIG. 4B, assume that application server 170 decides at 456B to prompt the originating UE to transition to the CELL_DCH state. Therefore, the application server 170 transmits a dummy packet to the RAN 120 for transmission to the originating UE, and the dummy packet has a size equal to or larger than the downlink event 4a threshold (460B). Thus, the dummy packet is set large enough (eg, above the downlink event 4a threshold) to cause a transition mechanism for the originating UE to the RAN 120's unique CELL_DCH state.

  Referring to FIG. 4B, the RAN 120 (specifically, the serving RNC of the RAN 120) receives the dummy packet, and based on the dummy packet that makes the downlink traffic volume larger than the downlink event 4a threshold, Is determined to shift to the CELL_DCH state (464B). Therefore, after establishing a radio link (RL) between serving Node B and serving RNC at RAN 120 for DCH at 468B, RAN 120 transmits a reconfiguration message to the originating UE via FACH (472B). As will be appreciated, the reconfiguration message is based on whether the radio bearer (RB), transport channel (TCH), or physical channel (PCH) is an upper layer of the originating UE to be reconfigured, It may correspond to a radio bearer reconfiguration message, a transport channel reconfiguration message, or a physical channel reconfiguration message.

  The originating UE receives the reconfiguration message, transitions to the CELL_DCH state, executes the L1 synchronization procedure (476B), and then the originating UE sends a reconfiguration complete message to the RAN 120 on DCH or E-DCH. (480B). Then, the RAN 120 transmits a dummy packet to the originating UE via DCH or HS-DSCH (484B), and the originating UE decodes the dummy packet and drops it (488B).

  FIG. 4C shows another exemplary implementation of a portion of the process of FIG. 4A, according to an embodiment of the invention. Specifically, FIG. 4C shows an example of the process of FIG. 4A for the originating UE, where the originating UE starts in a CELL_FACH state.

  Referring to FIG. 4C, a given UE (“originating UE”) is operating in the CELL_FACH state (400C), and a request for the originating UE to initiate a communication session that is arbitrated by the application server 170. (E.g. a user of a given UE presses the PTT button) (404C) and the originating UE sends a call request message in RACH to initiate a communication session in CELL_FACH state Is determined (408C).

  Since the originating UE is already in the CELL_FACH state, the originating UE does not need to perform the cell update procedure to transition to the CELL_FACH state as shown in FIG. 4B. Accordingly, FIG. 4C omits the step of exchanging cell update messages, cell update confirmation messages, and cell update confirmation response messages as in 420B, 424B and 444B of FIG. 4B. Except for this difference, the other parts of FIG. 4C substantially correspond to FIG. 4B and will not be further described for the sake of brevity. Specifically, 412C to 464C in FIG. 4C correspond to 432B to 440B and 448B to 488B in FIG. 4B, respectively.

  FIG. 4D shows an exemplary implementation of another portion of the process of FIG. 4A, according to an embodiment of the invention. Specifically, FIG. 4D shows an example of the process of FIG. 4A for a target UE, where the target UE starts in a CELL_URA or CELL_PCH state.

  Referring to FIG. 4D, a given UE (target UE) is operating in either the URA_PCH state or the CELL_PCH state (400D), and the application server 170 receives a call request message from the originating UE (not shown). Is received (404D). Therefore, the application server 170 transmits a notification message to the RAN 120 for transmission to the target UE (408D).

  As will be appreciated by those skilled in the art, the application server 170 is generally not aware of whether the target UE is connected to the RAN 120 in the CELL_FACH state or the RAN 120 in the CELL_DCH state. However, in order to improve performance and reliability during the communication session, the application server 170 generally desires to maintain the target UE in the CELL_DCH state. Accordingly, in an embodiment of the present invention, the application server 170 determines whether to prompt the target UE to transition to the CELL_DCH state in 412D. For example, the application server 170 can evaluate the size of the notification message sent at 408D to infer whether the target UE is expected to be moved to the CELL_DCH state by the RAN 120, and the notification message is If the threshold is not exceeded, it can be determined to further encourage the target UE to transition to the CELL_DCH state. Alternatively, the determination of 412D may be determined to move the target UE to the CELL_DCH state whenever a notification message is transmitted, regardless of the size of the notification message. In a further example, in addition to the size of the call request message, the application server 170 may also consider the roaming state of the UE when determining whether the UE is expected to be in the CELL_DCH state. For example, if the UE is in a roaming network with a message size smaller than a threshold (assuming that the application server 170 knows such), the application server 170 has not yet transitioned to CELL_DCH I guess. In a further example, the application server 170 can evaluate the call type of the communication session and determine whether to prompt at 412D to move the CELL_DCH state of at least one target UE.

  In the embodiment of FIG. 4D, assume that the application server 170 decides to prompt the target UE to transition to the CELL_DCH state at 412D. Therefore, the application server 170 transmits a dummy packet to the RAN 120 for transmission to the target UE, and the dummy packet has a size equal to or larger than the downlink event 4a threshold (416D). When the notification message is received from 408D, since the target UE is in the URA_PCH state or the CELL_PCH state, the RAN 120 pages the target UE (420D). The target UE decodes the page from 420D and shifts to the CELL_FACH state (424D), and the target UE transmits a cell update message to the RAN 120 by RACH (428D). At 432D, the RAN 120 determines to move the target UE to the CELL_DCH state because the downlink traffic volume exceeds the downlink event 4a threshold due at least in part to dummy packets from 416D. Therefore, the RAN 120 sets up an RL connection between the serving RNC and the serving Node B for the target UE (436D), and sends a cell update confirmation message to the target UE instructing the target UE to transition to the CELL_DCH state. To the target UE (440D). As will be appreciated, the cell update confirmation message is based on whether the radio bearer (RB), transport channel (TCH), or physical channel (PCH) is an upper layer of the target UE to be reconfigured. It may correspond to a radio bearer reconfiguration message, a transport channel reconfiguration message, or a physical channel reconfiguration message.

  The target UE receives the cell update confirmation message, transitions to the CELL_DCH state, executes the L1 synchronization procedure (444D), and then the target UE transmits a cell update confirmation response message to the RAN 120 using DCH or E-DCH. (448D). The RAN 120 then sends an announcement message to the target UE N times (eg, N ≧ 1) at a given interval on DCH or HS-DSCH (452D), and the target UE is on DCH or E-DCH, In response to the notification message by the notification ACK message (456D), the RAN 120 transfers the notification ACK message to the application server 170 (460D). Then, the RAN 120 transmits a dummy packet N times using DCH or HS-DSCH (464D), and the target UE decodes and drops the dummy packet (468D). Therefore, in the embodiment of FIG. 4D, the decision for the dummy packet of the decision to transition to the CELL_DCH state of 420A of FIG. 4A for the target UE occurs with the transmission of the notification message.

  FIG. 4E shows an exemplary implementation of another portion of the process of FIG. 4A, according to an embodiment of the invention. Specifically, FIG. 4E shows an example of the process of FIG. 4A for a target UE, where the target UE starts in a CELL_URA or CELL_PCH state. Also, FIG. 4E determines whether to move the target UE to the CELL_DCH state after a notification ACK is received from the target UE, not when a notification message is transmitted to the target UE, as in FIG. 4D. An application server 170 is shown.

  Referring to FIG. 4E, a given UE (target UE) is operating in either the URA_PCH state or the CELL_PCH state (400E), and the application server 170 receives a call request message from the originating UE (not shown). Is received (404E). Accordingly, the application server 170 transmits a notification message to the RAN 120 for transmission to the target UE (408E).

  When the notification message is received from 408E, since the target UE is in the URA_PCH state or the CELL_PCH state, the RAN 120 pages the target UE (412E). The target UE decodes the page from 412E, transitions to the CELL_FACH state (416E), and the target UE transmits a cell update message to the RAN 120 in RACH (420E). In 424E, the RAN 120 determines not to move the target UE to the CELL_DCH state because the downlink traffic volume does not exceed the downlink event 4a threshold. Therefore, the RAN 120 does not need to set up an RL connection between the serving RNC and the serving Node B for the target UE, but instead N notifications on the FACH at a given interval to the target UE. Send a message (428E). After the notification message is transmitted in 428E, the RAN 120 transmits a cell update confirmation message instructing the target UE to remain in the CELL_FACH state to the target UE using the FACH (432E). As will be appreciated, the cell update confirmation message is based on whether the radio bearer (RB), transport channel (TCH), or physical channel (PCH) is an upper layer of the target UE to be reconfigured. It may correspond to a radio bearer reconfiguration message, a transport channel reconfiguration message, or a physical channel reconfiguration message.

  Conventionally, when a cell update message is received from the target UE, the RAN 120 responds with a cell update confirmation message, after which the RAN 120 is allowed to transmit data to the target UE over FACH. However, in the embodiment of FIG. 4E, the target UE and RAN 120 are configured to allow the RAN 120 to transmit data before the cell update confirmation message is transmitted. An example of how the target UE and RAN 120 may be configured to facilitate this type of “early” data transmission on the FACH, May 22, 2009, incorporated herein by reference in its entirety No. 61 / 180,640, US Patent Application Ser. No. 091948, entitled “TRANSMITTING A REQUEST TO INITIATE A COMMUNICATION SESSION WITHIN A WIRELESS COMMUNICATIONS SYSTEM”. As will be appreciated, data may be transmitted earlier by sending a notification message before the call update confirmation message, but this is not necessarily an essential feature in each embodiment of the invention.

  The target UE responds to the cell update confirmation message by returning a cell update confirmation response message to the RAN 120 by RACH (436E), and the target UE sends a notification ACK message to the RAN 120 by RACH to call 428E. In response to the announcement message (440E), the announcement ACK message is then forwarded by the RAN 120 to the application server 170 (444E).

  The application server 170 receives the notification ACK message, and determines whether to prompt the target UE to transition to the CELL_DCH state at 448E. For example, the application server 170 evaluates the size of the announcement message sent at 408E and / or the size of the announcement ACK message received at 448E, and it is expected that the target UE is already operating in the CELL_DCH state. You can guess whether or not. The application server 170 may then determine to further prompt the target UE to transition to the CELL_DCH state if each of these messages does not exceed the threshold. In a further example, in addition to the size of the call request message, the application server 170 may also consider the roaming state of the UE when determining whether the UE is expected to be in the CELL_DCH state. For example, if the UE is in a roaming network with a message size smaller than a threshold (assuming that the application server 170 knows such), the application server 170 has not yet transitioned to CELL_DCH I guess. Alternatively, the determination of 448E may determine to move the target UE to the CELL_DCH state whenever a notification ACK message is received from the target UE, regardless of the size of the notification message or the size of the notification ACK message. . In a further example, the application server 170 can evaluate the call type of the communication session to determine whether to prompt at 448E to transition the CELL_DCH state of at least one target UE.

  In the embodiment of FIG. 4E, assume that the application server 170 decides to prompt the target UE to transition to the CELL_DCH state at 448E. Accordingly, the application server 170 transmits a dummy packet to the RAN 120 for transmission to the target UE, and the dummy packet has a size equal to or larger than the downlink event 4a threshold (452E). The RAN 120 receives the dummy packet and determines to move the target UE to the CELL_DCH state based on the fact that the downlink traffic amount of the target UE exceeds the downlink event 4a threshold (456E). Accordingly, the RAN 120 sets the RL between the serving RNC and the serving Node B for the target UE (460E), and the RAN 120 sends a reconfiguration message that instructs the target UE to transition to the CELL_DCH state. Transmit to the target UE via FACH (464E).

  The target UE receives the reconfiguration message, transitions to the CELL_DCH state, performs the L1 synchronization procedure (468E), and then the target UE sends a reconfiguration complete message to the RAN 120 on DCH or E-DCH (472E). ). The RAN 120 then transmits a dummy packet to the target UE N times (eg, N ≧ 1) at a given interval on the DCH or HS-DSCH (476E), and the target UE decodes the dummy packet and drops it (480E). Accordingly, in the embodiment of FIG. 4D, the decision on transition to the CELL_DCH state of 420A of FIG. 4A for the target UE occurs when a notification ACK message is received from the target UE.

  FIG. 4F shows another exemplary implementation of a portion of the process of FIG. 4A, according to an embodiment of the invention. Specifically, FIG. 4F is similar to FIG. 4D, except that the target UE is assumed to start in the CELL_FACH state instead of the URA_PCH state or the CELL_PCH state.

  Thus, referring to FIG. 4F, unlike FIG. 4D, it is assumed that a given UE (“target UE”) is operating in the CELL_FACH state (400F). 404F-416F correspond to 404D-416D in FIG. 4D, respectively, and will not be further described for the sake of brevity.

  Since the target UE is already in the CELL_FACH state, the RAN 120 transmits a notification message on the FACH N times at a given interval to the target UE (420F). The header portion of the 420F announcement message transmission may be configured to include a cell identifier (eg, C-RNTI) of the target UE. The announcement message is being sent to the target UE on FACH, but because the downlink traffic volume exceeds the downlink event 4a threshold due at least in part to dummy packets from 416F, 424F, the RAN 120 Decides to transition to CELL_DCH state. Accordingly, the RAN 120 sets up an RL connection between the serving RNC and the serving Node B for the target UE (428F).

  After decoding at least one of the notification messages from 420F, the target UE responds to the notification message by sending a notification ACK message to RAN 120 in RACH (432F), and RAN 120 sends the notification ACK message to the application. Transfer to server 170 (436F).

  After the RL configuration at 428F is complete, the RAN 120 may request a reconfiguration message (e.g., radio bearer (RB), transport channel (TCH), or physical channel (PCH) to instruct the target UE to enter the CELL_DCH state. ) Sends a radio bearer reconfiguration message, transport channel reconfiguration message or physical channel reconfiguration message) to the target UE on the FACH based on whether it is an upper layer of the target UE to be reconfigured (440F ).

  The target UE receives the reconfiguration message, transitions to the CELL_DCH state, performs the L1 synchronization procedure (444F), and then the target UE sends a reconfiguration complete message to the RAN 120 on DCH or E-DCH (448F). ). The RAN 120 then sends a dummy message to the target UE N times (eg, N ≧ 1) at a given interval on DCH or HS-DSCH (452F), and the target UE decodes the dummy packet and drops it (456F). Therefore, in the embodiment of FIG. 4F, the decision for the dummy packet of the decision to transition to the CELL_DCH state of 420A of FIG. 4A for the target UE occurs with the transmission of the notification message.

  It will be appreciated that FIG. 4F shows an example in which a notification ACK is sent in RACH before a reconfiguration complete message is sent by the target UE and while the target UE is still in CELL_FACH state. FIG. 4G shows an alternative implementation of the process of FIG. 4F, where the announcement ACK is sent from the target UE only after a reconfiguration complete message is sent. Therefore, in FIG. 4G, the transmission of the notification ACKs of 432F and 436F in FIG. 4F is not executed. Instead, a notification ACK message is sent at 444G and 448G after the target UE sends a reconfiguration complete message at 440G (eg, as at 448F in FIG. 4). Also, since the target UE has transitioned to the CELL_DCH state at this point in the process of FIG. 4G (436G), the 444G notification ACK message is transmitted on a more reliable and faster DCH or E-DCH. Otherwise, FIG. 4G is similar to FIG. 4F and related elements (eg, 452G and 456G) are not further described for the sake of brevity.

  FIG. 4H illustrates another exemplary implementation of a portion of the process of FIG. 4A, according to an embodiment of the invention. Specifically, FIG. 4H is similar to FIG. 4E except that it is assumed that the target UE starts in the CELL_FACH state instead of the URA_PCH state or the CELL_PCH state.

  Therefore, referring to FIG. 4H, unlike FIG. 4E, it is assumed that a given UE (“target UE”) is operating in the CELL_FACH state (400H). The application server 170 receives a call request message from the originating UE (not shown) (404H). Therefore, the application server 170 transmits a notification message to the RAN 120 for transmission to the target UE (408H).

  When the notification message is received at 408H, the RAN 120 determines that the target UE is not to be shifted to the CELL_DCH state because the downlink traffic volume does not exceed the downlink event 4a threshold (412H). In addition, since the target UE is already in the CELL_FACH state, the RAN 120 transmits N notification messages to the target UE through the FACH at a given interval (416H). The other parts of FIG. 4H are similar to FIG. 4E and will not be further described for the sake of brevity. Specifically, 420H to 460H in FIG. 4H correspond to 440E to 480E in FIG. 4E, respectively.

  While references in the above-described embodiments of the present invention generally use the terms “call” and “session” interchangeably, any call and / or session may be used between different parties. It should be understood that the call is to be interpreted as an alternative to a data transport session that may not be considered technically a “call”. Also, although the above embodiments are generally described with respect to PTT sessions, other embodiments may be targeted for any type of communication session, eg, push-to-transfer (PTX) sessions, emergency VoIP calls, etc. Good.

  Those of skill in the art will understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or optical particles, or any of them Can be represented by a combination.

  Further, it is understood that the various exemplary logic blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or a combination of both. The merchant will be understood. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functions are implemented as hardware or software depends on the specific application and design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in a variety of ways for each particular application, but such implementation decisions should not be construed as departing from the scope of the invention.

  Various exemplary logic blocks, modules, and circuits described with respect to the embodiments disclosed herein include general purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs). ) Or other programmable logic device, individual gate or transistor logic, individual hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, eg, a DSP and microprocessor combination, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. obtain.

  The methods, sequences, and / or algorithms described in connection with the embodiments disclosed herein may be implemented directly in hardware, in software modules executed by a processor, or in a combination of the two. Software modules reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art May be. An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium can reside in an ASIC. The ASIC may reside in a user terminal (eg, access terminal). In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

  In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and computer communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer readable media can be RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage device, or a desired program in the form of instructions or data structures. Any other medium that can be used to carry or store the code and that can be accessed by a computer can be included. Any connection is also properly termed a computer-readable medium. For example, software is sent from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave. Wireless technologies such as coaxial cable, fiber optic cable, twisted pair, DSL, or infrared, radio, and microwave are included within the definition of the medium. As used herein, a disk and a disc include a compact disc (CD), a laser disc, an optical disc, a digital versatile disc (DVD), a flexible disc, and a Blu-ray disc. ) Normally reproduces data magnetically, and a disc optically reproduces data with a laser. Combinations of the above should also be included within the scope of computer-readable media.

  While the above disclosure represents exemplary embodiments of the present invention, various changes and modifications may be made herein without departing from the scope of the invention as defined by the appended claims. Please keep in mind. The functions, steps and / or actions of a method claim according to embodiments of the invention described herein may not be performed in a particular order. Further, although elements of the invention may be described or claimed in the singular, the plural is contemplated unless expressly stated to be limited to the singular.

100 wireless communication system
102 UE
104 Air interface
108 UE
110 UE
112 UE
120 wireless access network
122 RNC
124 Node B
126 Core network
160 Serving GPRS support nodes
162 Packet data network endpoint
165 Gateway GPRS support node
170 Application server
170A regional dispatcher
170B MCC
175 Internet
182 Accounting (AAA) server
184 Provisioning Server
186 IMS / SIP registration server
188 Routing unit
202 platform
206 transceiver
208 Application specific integrated circuits
210 Application Programming Interface
212 memory
214 Local database
222 Antenna
224 display
226 keypad
228 PushTalk button

Claims (24)

A method for selectively transitioning a state of a user equipment UE in a wireless communication system,
Receiving at the application server a call message configured to request initiation of a communication session between the originating UE and at least one target UE, which is arbitrated by the application server;
Transitioning the originating UE of the communication session to a dedicated channel state, selectively transmitting dummy data to a serving access network of the originating UE associated with the communication session in response to the call message And determining whether to transition the originating UE to the dedicated channel state based at least in part on whether the communication session is a delay sensitive application,
The method of selectively transmitting, wherein the dummy data is transmitted based on a result of the determination. A method for selectively transitioning a state of a user equipment UE in a wireless communication system,
Receiving at the application server a call message configured to request initiation of a communication session between the originating UE and at least one target UE, which is arbitrated by the application server;
Transitioning the at least one target UE of the communication session to a dedicated channel state, and selecting dummy data for a serving access network of the at least one target UE associated with the communication session in response to the call message Transmitting and determining, based on the roaming state of the at least one target UE, determining whether to move the at least one target UE to the dedicated channel state,
The method of selectively transmitting, wherein the dummy data is transmitted based on a result of the determination.   The method according to claim 1, wherein the selectively transmitting step transmits the dummy data to the serving access network with an acknowledgment ACK for the call message for transmission to the originating UE.   The selectively transmitting step is configured to announce the dummy data to the serving access network to the at least one target UE for transmitting to the at least one target UE. The method according to claim 2, wherein the method is transmitted together with a notification message. Sending an announcement message configured to announce the communication session to the at least one target UE;
Receiving from the at least one target UE an acknowledgment indicating receipt of the announcement message;
3. The method of claim 2, wherein the selectively transmitting step transmits the dummy data to the serving access network in response to the acknowledgment from the at least one target UE. Further comprising determining whether to cause the originating UE to transition to the dedicated channel state based at least in part on a size of a given message associated with setting up the communication session;
The method of claim 1, wherein the selectively transmitting step transmits the dummy data based on a result of the determination.   The given message in the call message from the originating UE, a notification message sent by the application server to announce the communication to the at least one target UE, and / or in the notification message; The method according to claim 6, corresponding to an acknowledgment received from the at least one target UE in response. Said determining step comprises:
Comparing the size of the given message to a size threshold;
Determining that the originating UE transitions to the dedicated channel state if the result of the comparison indicates that the size of the given message is less than the size threshold;
Determining that the originating UE does not transition to the dedicated channel state if the comparison result indicates that the size of the given message is not less than the size threshold. 6. The method according to 6. If the comparison result indicates that the size of the given message is less than the size threshold, the application server assumes that the originating UE has not yet transitioned to the dedicated channel state When,
If the comparison result indicates that the size of the given message is not less than the size threshold, the application server assumes that the originating UE has already transitioned to the dedicated channel state 9. The method of claim 8, comprising the steps. The comparison result, if the size of the given message indicating that less than a threshold of the size, the application server, the originating UE is without transmission of the dummy data is not shifted to the dedicated channel state Step to guess,
If the comparison result indicates that the size of the given message is not smaller than the size threshold, the application server causes the originating UE to transition to the dedicated channel state without transmitting the dummy data 9. The method of claim 8, comprising the step of inferring. 9. The method of claim 8, wherein the size threshold is not greater than an event 4a traffic volume measurement TVM threshold of the serving access network of the originating UE. If the communication session type corresponds to a push-to-talk PTT or push-to-transfer PTX communication session, the determining step determines to move the originating UE or the at least one target UE to the dedicated channel state. The method according to claim 1 or 2. Said determining step comprises:
Comparing the communication session type with a given list of session types;
The selectively transmitting step transmits the dummy data based on whether the type of the communication session is included in the given list of session types;
The method of claim 1. The step of selectively transmitting comprises:
Configuring a dummy packet to transmit to the originating UE or the at least one target UE, the dummy packet having a size greater than or equal to a size threshold; and
Transmitting the configured dummy packet to the serving access network of the originating UE or the at least one target UE.   If the originating UE or the at least one target UE is not yet in the dedicated channel state, a data packet at least equal to the size sends the originating UE or the at least one target UE to the serving access network. 15. The method of claim 14, wherein the method is expected to prompt a transition to a dedicated channel state.   15. The method of claim 14, wherein the size threshold is greater than or equal to an event 4a traffic volume measurement TVM threshold of the serving access network of the originating UE or the at least one target UE.   The method according to claim 1 or 2, wherein the dedicated channel state corresponds to a CELL_DCH state in which the originating UE or the at least one target UE is allowed to transmit and receive on a given dedicated channel.   The selectively transmitting step transmits the dummy data to the serving access network of the originating UE in response to the reception of the call message regardless of the size of the call message. The method described. An application server configured to selectively transition a state of a user equipment UE within a wireless communication system,
Means for receiving a call message configured to request initiation of a communication session between an originating UE and at least one target UE, which is arbitrated by the application server;
Means for facilitating transition of the communication session to a dedicated channel state of the originating UE;
Means for selectively transmitting dummy data to a serving access network of the originating UE of the communication session associated with the communication session in response to the call message, the communication session being affected by a delay; Means for determining whether to cause the originating UE to transition to the dedicated channel state based at least in part on whether it is an easy application;
Including
Selectively transmitting the dummy data based on a result of the determination;
Application server. An application server configured to selectively transition a state of a user equipment UE within a wireless communication system,
Means for receiving a call message configured to request initiation of a communication session between an originating UE and at least one target UE, which is arbitrated by the application server;
Means for facilitating transition of the communication session to a dedicated channel state of the at least one target UE;
Means for selectively transmitting dummy data to a serving access network of the at least one target UE of the communication session associated with the communication session in response to the call message;
Means for determining whether to move the at least one target UE to the dedicated channel state based on a roaming state of the at least one target UE;
Selectively transmitting the dummy data based on a result of the determination;
Application server. An application server configured to selectively transition a state of a user equipment UE within a wireless communication system,
A logic circuit configured to receive a call message configured to request initiation of a communication session between an originating UE and at least one target UE, which is arbitrated by the application server;
A logic circuit configured to transition the originating UE of the communication session to a dedicated channel state, the serving access of the originating UE of the communication session associated with the communication session in response to the call message Transitioning the originating UE to the dedicated channel state based at least in part on a logic circuit configured to selectively transmit dummy data to the network and whether the communication session is a delay sensitive application An application server, wherein the step of selectively transmitting includes a logic circuit that transmits the dummy data based on a result of the determination. An application server configured to selectively transition a state of a user equipment UE within a wireless communication system,
A logic circuit configured to receive a call message configured to request initiation of a communication session between an originating UE and at least one target UE, which is arbitrated by the application server;
A logic circuit configured to transition the at least one target UE of the communication session to a dedicated channel state, wherein the at least one target of the communication session associated with the communication session in response to the call message A logic circuit configured to selectively transmit dummy data to the serving access network of the UE;
Selectively transmitting based on a logic circuit configured to determine whether to move the at least one target UE to the dedicated channel state based on a roaming state of the at least one target UE, An application server comprising: a logic circuit that transmits the dummy data based on a result of the determination. A computer readable recording medium for recording instructions, wherein when the instructions are executed by an application server configured to selectively transition a state of the user equipment UE in a wireless communication system, the application server operates And the instruction is
Program code for receiving a call message that is configured to request the initiation of a communication session between the originating UE and at least one target UE, which is arbitrated by the application server;
Facilitating the transition of the communication session to a dedicated channel state of the originating UE, and further, in response to the call message, dummy data in the serving access network of the originating UE of the communication session associated with the communication session Program code for selective transmission, and
Program code for determining whether to cause the originating UE to transition to the dedicated channel state based at least in part on whether the communication session is a delay sensitive application;
The computer-readable recording medium, wherein the step of selectively transmitting transmits the dummy data based on the result of the determination. A computer readable recording medium for recording instructions, wherein when the instructions are executed by an application server configured to selectively transition a state of the user equipment UE in a wireless communication system, the application server operates And the instruction is
Program code for receiving a call message that is configured to request the initiation of a communication session between the originating UE and at least one target UE, which is arbitrated by the application server;
Facilitating the transition of the communication session to a dedicated channel state of the at least one target UE, and in response to the call message, the serving access network of the at least one target UE of the communication session associated with the communication session Program code for selectively transmitting dummy data to
Program code for determining whether to move the at least one target UE to the dedicated channel state based on a roaming state of the at least one target UE, and
The computer-readable recording medium, wherein the step of selectively transmitting transmits the dummy data based on the result of the determination.

Images