Dynamic allocation of radio resources in a packet switched communications system

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

The present invention relates to mobile communications, such as cellular communications. The present invention is not particularly limited, but is applicable to a GSM type mobile communication device. [0002]

An example of cellular communications that provide voice transmission services is the Motorola integrated digital wide area network, or iDEN system. The system includes wide area base transceivers (EBTSs) at cell sites that connect mobile terminals to fixed network equipment via a TDMA wireless interface and are connected to control base station controllers (BSCs). BSCs are linked to mobile switching stations (MSCs), which provide a public service telephone network (PSTN) for conventional circuit switching, and metro packet switching (MPS), which exchanges for outgoing services. The outgoing application processor (DAP) integrates and controls outgoing communications by registering the identification and location of mobile terminals in this system. [0003]

The iDEN system provides voice transmission services, circuit exchange call services and other data communication services such as short message services. [0004]

U.S. Patent Application 5,416,770 describes a voice-transmitting cellular communication device that transports audio data packets over a Frame Relay link. Communication is established between a plurality of communication units by duplicating the transmission data packet and distributing the duplicated packet to the identification target base station. [0005]

U.S. patent application 5,448,620 describes a mobile terminal capable of operating in both voice transmission mode and telephone interconnect mode. [0006]

A well-known GSM network called the Public Land Mobile Network (PLMN) is schematically illustrated in Figure 1. Connect mobile exchanges (MSCs) 2 to a number of base station controllers (BSCs) 4 via communication links. BSCs 4 are geographically dispersed over the area used by Mobile Exchange 2. Each BSC4 controls one or more Base Transceiver Stations (BTSs) 6 that are remote from the BSC and are connected to the BSC by another communication link. Each BTS 6 transmits a radio signal to a mobile station 8 within the area used by the BTS and receives the radio signal from the mobile station 8. That area is called a "cell". A GSM network comprises a very large number of such cells that are ideally adjacent so that the entire network territory is a continuous service area. [0007]

The mobile communication station 2 is connected to the remaining other mobile exchanges of the mobile communication network 10 via a communication link to other networks such as the Public Switched Telephone Network (PSTN) (not shown). The mobile exchange 2 includes a home location register (HLR) 12 which is a database that stores subscriber authentication data including an international mobile subscriber identity (IMSI) unique to each mobile station 8. The IMSI also stores in the subscriber identification module (SIM) together with other subscriber identification information in the mobile station. [0008]

The mobile exchange also includes a visitor location register (VLR) 14, which is a database that temporarily stores subscriber authentication data for mobile stations that is valid in the area. [0009]

GSM was originally designed to support full-duplex circuit exchange voice telephones. [0010]

A new element of functionality is added to the GSM Phase 2+ technical specification called Advanced Voice Call Item (ASCI). This makes a group call that broadcasts to members inside the group. To establish a broadcast group call, the first mobile station sends a service request to the MSC, including the request group identification. MSC authenticates subscribers with VLR. [0011]

If the authentication check is successful, the MSC requests identification data for the members of the group from the group call register. With this information, the MSC establishes a connection between the receiving mobile station and the group call originator. Each cell in which the receiving mobile station is located pages a notification that includes identification of the called group and a description of the channel assigned for group call broadcasting. The group call originator sends the group call data to each of the cells for broadcasting on the placement channel. [0012]

Another functional element added to GSM within the GSM Phase 2+ technical specification is General Packet Radio Service (GPRS). [0013]

GPRS provides a packet mode service that transfers high-speed and low-speed data over the GSM wireless network and sends signals efficiently. GPRS is designed to support a range of data transfer types, from intermittent and burst data transfers to accidental transfers of large volumes of data. GPRS envisions Internet services, email and other data services. [0014]

GPRS has a mechanism for both point-to-point (PTP) and point-to-multipont (PTM) data packet transfer. In PTM data packet transfer, a data packet is broadcast to all cells within a given geographic area. In each case, other than receiving the data packet correctly and reliably at its destination, GPRS reveals and sends the data packet unless the network side has knowledge of the contents of the data packet. [0015]

Place the GPRS radio interface in any number of TDMA time slots of the GSM mechanical radio interface used for circuit exchange traffic and signal channels. The same GPRS radio source is shared by all mobile stations in the cell. This radio source is retained by or for mobile stations only when data packets are sent. [0016]

Packet-oriented networks Core telecommunications equipment has packet switching in the form of GPRS support nodes (GSNs) interconnected by the GPRS backbone network, and uses protocols such as TCP / IP, X25, etc. for external packet data protocols. It has a packet data network that includes a gateway GPRS support node (GGSN) that sends and receives data packets to and from the (PDP) network. [0017]

A aspect of the present invention provides a method of controlling communication between user stations by a mobile communication system having a wireless interface. The method is; Equipped with a data packet handler connected to the packet data network; Holds control data that displays the status of the telephone between the first user station and the second user station; The radio source is dynamically placed on the radio interface for the transfer of data packets carrying the call data for the phone so that the amount of allocated radio source depends on the amount of call data transferred at various points in the phone. ; The control data controls the transfer of data packets between the first and second user stations by using the data packet handler. [0018]

The state of the telephone is stored in a storage device on the network side, enabling control of communication between mobile stations. The functionality and radio source placement and control characteristics provided by the packet data network do not require an ongoing circuit exchange connection between user stations, even when data transfer is intermittent, during a call. It is like being able to transfer data to. The data to be transferred is voice call data or video call data. [0019]

Another aspect of the present invention provides a method of processing data transfer in a GSM mobile communication system. The method is; Receives the first data packet containing the recipient ID from the first user station; The recipient ID is mapped to the packet network protocol address and thereby sent to a second user station identified by the gateway GPRS support node; It transmits the second data packet including the packet network protocol address to the gateway GPRS support node. [0020]

From this point of view, GPRS provides a function that enables the transfer of data packets between user stations. Here, the first user station uses a well-known recipient ID rather than the packet network protocol address (which is only temporarily placed) to identify the second user station. [0021] [0021]

Another aspect of the present invention provides a method of communicating between user stations by a mobile communication system. Each user station comprises a camera that receives the user's image and a display that displays the image of a remote party, the method establishing a data transfer connection between the user stations and controlling the connection in half-duplex mode. Therefore, during the first cycle sufficient for the user station to transmit and receive the video data forming the video, either the video data is received or only transmitted, and the video data forming the video is transmitted and received. In the second cycle following the first cycle, which is sufficient for the above, the video data is either received only or transmitted only. [0022]

Another aspect of the present invention provides a mobile station adapted for video communication. The mobile terminal has a half-duplex mode communication mode controlled by a data processor, in which mode the transmission of the video data is blocked during reception of the video data, and the video data is transmitted during a cycle selected by the user. Enables transmission. [0023]

These perspectives provide communication methods and mobile stations and are used for new and advantageous video conferencing. By limiting this communication to half-duplex mode, the bandwidth and mobile station power specifications required for the telephone can be reduced. [0024]

Further, it is possible to operate a transmission communication mode in which video data is distributed among a group of recipients who both transmit and receive data. One party catches the phone and sends the video data received by the rest of the parties. The call is then subsequently caught by different parties. [0025]

Yet another aspect of the present invention is set forth in the appended claims, the features of which will become apparent from the following description. [0026]

Embodiments of the present invention will be described herein by way of reference with reference to the accompanying drawings. [0027]

In FIG. 2, the GSM compatible mobile station 8 according to the embodiment of the present invention is a handset, which includes a transceiver antenna 16, a radio frequency transceiver 18, a GPRS module 19 including a packetizer / depacketizer and a buffer storage device, a loudspeaker 22 and a microphone 24. It consists of a connected speech coder / decoder 20, a processor circuit 26 and its associated memory 28, an LCD display 30, a manual input port (keypad) 32 and a push talk button 34. Connect this mobile station to a removable subscriber identification module (SIM, not shown) via electrical contacts. [0028]

FIG. 3 is a schematic view of the GSM type PLMN deployed according to the embodiment of the present invention. The PLMN has a GPRS support node including one or more serving GPRS support nodes (SGSNs) 40 and a gateway GPRS support node (GGSN) 44. The PLMN contains all of the components described in connection with Figure 1. The mobile station 8 can make a circuit exchange call via the MSC immediately after camping in the serving cell as in the prior art. [0029]

The GGSN44 is a node provided to interface PLMN with an external packet data network 46, for example, a TCP / IP network. It contains routing information for active GPRS users in PLMN and is used to send data packets belonging to the Packet Data Protocol Protocol Data Units (PDP PDUs) from the packet data network to the current point of the mobile station's installation in PLMN. .. The GGSN provides a mapping function for mapping Packet Data Protocol (PDP) addresses, thereby identifying mobile users within the packet data network 46 and identifying mobile users within PLMN. The mobile user's PDP address matches the standard address scheme of each network layer service used within the packet data network 46, such as IP version 4 address, IP version 6 address or X.121 address. [0030]

The mobile user may be assigned a permanent or static PDP address stored in mobile stations 8 and HLR12, or may request a temporary or dynamic PDP address to be located by the GGSN44 upon request. Be placed. [0031]

SGSNs40,42 are called serving GPRS support nodes. Because these nodes are nodes that utilize mobile station 8 within their routing area. When you log on to the mobile station's GPRS service, SGSN establishes a mobility management environment that contains information related to mobile station mobility and safety. SGSN also establishes a routing environment called within GPRS as a "PDP environment" using GGSN44, which is used by mobile station 8 to access the packet data network 46. [0032]

The functionality of SGSN and GGSN can be combined within the same mechanical node or kept in different mechanical nodes. [0033]

The packet data network 46 is a public internet, intranet connection, that is, a dedicated line. The packet data network 46 connects with other components, such as the GGSN 56 or fixed terminal 58 of other PLMNs. [0034]

Therefore, adding the functionality of SGSNs40 and GGSN44 in PLMN and GPRS module 19 in mobile station 8 enables the mobile network and users to enable GPRS, which allows mobile users to send and receive packet mode data. For example, a mobile user can use a terminal device attached to mobile station 8 on the public internet to provide the gateway functionality provided by GGSN44 and the rest of the network including SGSNs40, 42, BSCs4, BTSs6, GPRS wireless interfaces. Web pages can be accessed using mobile station 8 via the packet mode transfer functionality provided. [0035]

The GPRS wireless interface is described in GSM 03.64 version 5.1.0; Comprehensive description of the GPRS wireless interface; Stage 2 published by the European Telecommunications Standards Institute, entitled "Digital Cellular Communication System (Phase 2+)". These contents are incorporated here with reference. [0036]

GPRS architecture and transmission mechanism, mobile management functionality, network management functionality, radio source functionality, packet routing transfer functionality, GPRS transmission and information storage are named "Digital Cellular Remote Communication System (Phase 2+)". GSM 03.60 version 5.2.0; General Line Radio Service (GPRS); described in Stage 2 of the European Telecom Standards Association publication. These contents are incorporated here with reference. [0037]

In addition to the standard GPRS core telecommunications equipment, embodiments of the mobile communication system of the present invention include an outgoing packet handler 48, a packet storage device 50, a packet user database (PUD) 52 and a service management terminal 54. [0038]

The packet handler 48 is responsible for setting up virtual connections between GPRS users in the PLMN and replicating packets when distributing data packets to groups of users. [0039]

The packet storage device 50 is responsible for storing data packets intended to be distributed to GPRS users inside the PLMN that cannot be contacted via GPRS when the packet handler 48 receives a data packet for a non-contactable user. [0040]

The packet user database 52 maintains a record of service data used by the packet handler 48 to set up and manage virtual connections between GPRS users in the PLMN. Update the service data in PUD52 using the service management terminal 54. [0041]

PUD52 keeps a record of the call group to identify the members of the call group. Figure 4 shows a record of a representative call group. The fields of a single call group are identified by the call group ID that includes field 60. Two or more mobile station IDs, MSID1, MSID2 ... MSIDn is included in field 62, and each mobile station ID field 62 signals the related mobile station that the call group is currently captured (related phone occupancy). seize) Has field 64. [0042]

In addition to the call group record, the packet user database 52 stores an identification record for each mobile subscriber in PLMN with a valid subscription to the GPRS virtual connection service of the present invention. In Figure 5, each such subscriber has a permanent mobile station ID 66, a field 68 to include the currently deployed PDP address, and a currently problematic mobile subscription to include the call group ID. Has a mobile subscriber record that includes field 66, including field 70 for users. If the PDP address field 68 is empty, this indicates that the mobile station is not currently attached to the GPRS service. If the current call group ID field 70 is empty, this indicates that the subscriber is not currently participating in the GPRS virtual connection call. [0043]

FIG. 6 illustrates the procedure performed by mobile station 8 to participate in the GPRS virtual connection service of the present invention. To use the GPRS service, the user initializes the GPRS logon procedure from mobile station 8 (step 100). [0044]

The GPRS logon signaling procedure is described in GSM 03.60 V.5.2.0, Part 6.5, named "Attach Function", which is specifically incorporated here for reference. This part also describes the procedure for activating the PDP environment at logon and belongs to Part 9.2.2 of the same document name "Activation Procedure" specifically incorporated here for reference. [0045]

After performing the GPRS attach, the mobile station is "ready", packet transfer occurs via the GPRS radio interface between mobile station 8 and PLMN, and a mobility management environment is established with the mobile station and SGSN40. The mobile station then activates its PDP environment by sending a request to SGSN40 to'activate the PDP environment'. If the mobile station uses a static PDP address, the mobile station sends the static PDP address in the request to'activate the PDP environment'. [0046]

SGSN40 queries HLR12, which holds GPRS subscription information for subscribers, to check that mobile station 8 is allowed to activate the PDP address included in the request. If possible, SGSN sends a request to GGSN44 to make a new entry in the PDP environment table held in HLR12 for GGSN44. This PDP environment table has a mobile station entity and a PDP address assigned to the mobile station, and the GGSN44 can map between these two entities, thereby sending data packets between the SGSN40 and the packet data network 46. [0047]

If mobile station 8 is not using a static PDP address, the request for'create a PDP environment'sent to GGSN44 by SGSN40 is a GGSN with a dynamic PDP address that can be signaled to mobile station 8 via SGSN40. Bring. [0048]

Even if the mobile station uses a static PDP address or a dynamic PDP address, the mobile station 8 has a PDP address in each case, thereby identifying the routing for packets arriving from the packet data network 46. The routing inside the PLMN is created by the GPRS data packet encapsulation procedure, which removes encapsulation from the data packets on the GGSN44 and mobile station 8. The encapsulation function is described in Part 9.6 of document GSM 03.60 V.5.2.0, which is partially specifically incorporated here for reference. GPRS clearly supports the transfer of PDP PDUs between external networks and mobile stations. One encapsulation scheme (referred to here as GSN-GSN encapsulation) is used for the GPRS backbone between GSNs in PLMN, and one (here referred to as SGSN-MS encapsulation) is between SGSN40 and mobile station 8. Used for GPRS connection. [0049]

When a PDP environment entry is created in HLR12 by GGSN44 for a newly logged on GPRS user, GGSN44 sends a logon message to the packet handler and the move held in field 66 of the mobile station record held in PUD52. It informs the packet handler 48 of the mapping between station entities, thereby configuring the GGSN44 so that the user is permanently identified within the PLMN and assigned PDP address. Upon receiving the logon message, packet handler 48 puts the placed PDP address in field 68 of the mobile subscriber record for the subscriber in question. [0050]

Upon logging on to the GPRS service, the mobile station sends the data packet to the packet handler 48 and receives the data packet from the packet handler 48. [0051]

The data packet generated in mobile station 8 is transmitted to SGSN40 via BTS6 and BSC4 on the wireless interface. When the SGSN40 receives the packet completely and accurately, it encapsulates the packet in a GPRS backbone network packet sent to the GGSN44. The GGSN44 takes the packet out of the capsule and sends the data packet to the packet handler 48 by the PDP address assigned to the sender as the packet start address of the header part of the data packet. [0052]

The data packet generated in the packet handler 48 is transmitted to the mobile station 8 by attaching the arrangement PDP address held in the PUD 52 for the receiver to the data packet as the destination address in the header part of the data packet. Data packets are sent to GGSN44 via the packet data network 46. In the GGSN44, the PDP address of the receiver is read, and the SGSN using the mobile station is identified from the routing data held in the HLR12. The data packet is then encapsulated in GSN-GSN and sent to the identified SGSN. SGSN decapsulates the GPS backbone network, encapsulates the original data packet in SGSN-MS, and sends it to mobile station 8 via the BSC4, BTS6 and GPRS wireless interfaces. [0053]

When mobile station 8 receives the packet, it removes the SGSN-MS encapsulation and processes the data packet. If the data packet is a voice data packet, the series of packets is reassembled and a voice signal is generated in the mobile terminal. [0054]

The user can set up a phone by selecting a call group for which a virtual connection has been established from the storage table of the call group of which the mobile user is a member via the human-machine interface of the mobile station 8, for example, the keypad 32. Such selection is part of the initialization of the telephone setup transmission procedure (step 102) and is described below in connection with FIG. [0055]

Upon logging on to the GPRS service, the mobile station 8 can receive the telephone setting reception request from the packet handler 48, and initializes the procedure as described below in relation to FIG. Upon entering the telephone, mobile station 8 begins receiving call data packets (step 106) and may also begin transmitting call data packets (step 108), as described below in connection with FIGS. 7 and 8. it can. In addition, the user has the ability to terminate the entry into the phone by interacting with the human-machine interface of the mobile station 8, for example the keypad 32 (step 110), and the mobile station sends an entry termination request to the packet handler 48. Yes (step 112), and the call group ID can be deleted from its current phone record (step 114). [0056]

The user can also log off the GPRS service if desired (step 116), so that the mobile station 8 performs a log-off procedure that includes deleting the subscriber-assigned PDP address in the HLR record stored by the GGSN44 (step 116). 118). Upon receiving a logoff message from SGSN40, GGSN44 sends a logoff message to packet handler 48, resulting in a PDP address placed ahead of PDP address field 68 in the mobile subscriber record retained for subscribers in PUD52. Configure GGSN44 to remove. [0057]

In FIG. 7, when the user first instructs the mobile station 8 to set the phone for a specific call group by pressing the PTT button 34 after selecting the call group from the call group table stored in the SIM of the mobile station 8. The mobile station 8 sends a configuration request containing the selected call group ID as one or more GPRS data packets to the packet handler 48 (step 200). The call handler performs the steps described below in relation to FIG. 8, and upon success of those phone setup steps, the packet handler 48 may send a configuration confirmation message to the mobile station within the timeout settings within the mobile station 8. You can do it or not. If the phone configuration confirmation is not received by the mobile station within the timeout (step 202), the mobile station returns to the general GPRS logon state and mobile station 8 tries again by sending another phone configuration request. [0058] [0058]

When the configuration confirmation message is received from the packet handler 48 within the timeout, the mobile station 8 visually indicates to the user that the virtual connection has been established (step 204). In addition, the mobile station puts the call group ID selected by the user in the current phone record (step 206). [0059]

At this point, as long as the PTT button 34 is held down, the user can send voice data by speaking to the microphone 24. The audio signal is encoded by codec 20, the audio data is packetized, passed through a buffered GPRS module 19 (step 208), and SGSN-for transmission forward of the packet handler 48 on the GPRS radio interface by the radio frequency transceiver 18. MS capsules are encapsulated (step 210). [0060]

As soon as the PTT button 34 is released (step 212), the mobile station 8 creates a transmission end message in the form of a data packet and sends it to the packet handler 48 (step 214). [0061]

In FIG. 8, when a telephone configuration request is received (step 300), the call group ID contained within the telephone configuration request causes the packet handler 48 to identify the recipients who are currently available to receive the telephone configuration message from PUD52. Search the person record (step 302). Each mobile station in the call group record has an associated mobile station identified by the mobile station ID contained in the call group record. For each mobile station record, including the PDP address and non-current call group ID, a packet handler sends a configuration message with the PDP address retrieved for that mobile station (step 304). A mobile station record containing a non-distributed PDP address or a current call group ID is put in a telephone copy table in PUD52, and voice data packets received consecutively for the same call group are stored in the packet storage device 50 for storage. send. If the potential recipient has not yet logged on to the GPRS service, then when packet handler 48 receives a notification that the recipient has logged on, it then sends a configuration message, if desired, earlier unused. The recipient can receive the data held in the packet storage device 50. Similarly, if the recipient is making a different call and the potential recipient is unavailable, the packet handler 48 will set when the packet handler 48 receives an entry termination message from the potential recipient of the preceding call. In response by sending the message to the preceding unavailable recipient, the receiver can receive the data previously held in the packet storage device 50 if desired. If the packet handler does not receive approval from the available recipients who sent the configuration message within the timeout settings of packet handler 48 (step 306), the phone configuration is unsuccessful and the packet handler is in PUD52 or End the procedure without storing the criteria for the phone setup attempt in either of the packet storage devices 50. [0062]

Otherwise, the packet handler 48 puts the call group IDs for both the call setup request caller and the phone setup message recipient with the authorization phone setup into the current call group field 70 (step 308). If another recipient approves the phone settings, put the current call group ID for each of the added recipients in the call group ID field 70. [0063]

In addition, the packet handler 48 sets a phone occupancy flag in field 64 of the call group record corresponding to the mobile station ID of the caller soliciting phone settings, indicating that the caller can now send voice data (step 310). Send a configuration confirmation message to the caller (step 310). [0064]

When the caller receives the configuration confirmation message, the caller presses the PTT button 34 and begins sending the voice data packet received by the packet handler 48, as described in connection with FIG. 7 (step 312). If the number of recipients entering the phone now exceeds a single recipient (step 314), packet handler 48 duplicates the contents of each packet for each recipient (step 316). [0065]

After that, the received packet is transmitted to each entrant recipient (step 318) until the time of the end message is received from the voice packet transmission mobile station 8 (step 320). When the end message is received from the transmitting mobile station 8, the end message is sent to each recipient (step 322) and the phone occupancy flag is removed from field 64 in the call group record corresponding to the caller mobile station ID in PUD52. (Step 324). [0066]

In FIG. 9, when mobile station 8 receives a configuration message from packet handler 48 (step 400), mobile station 8 is included in the header portion of the data packet and is an outgoing call containing the individual subscriber's call group ID and name. Display the identity of the person (step 402). Upon answering, the recipient accepts the call by interacting with the mobile station's human-machine interface (step 404). If the user does not accept, the mobile station will not respond to the configuration message. Otherwise, mobile station 8 sends an approval to packet handler 48 and puts the call group ID in the current phone record held in mobile station memory 28 (steps 406 and 408). [0067]

As a result of the approval received by the packet handler 48, any data packet later transmitted by the voice data originator will be sent to the recipient mobile station 8 using the virtual connection created by the packet handler 48 (step). 410). The receiver mobile station 8 converts the data packet into voice data and outputs it as an audio signal until the time of the end message is received from the packet handler 48 (step 414) (step 412). [0068]

Upon receiving the termination message, the recipient mobile station notifies the user of the end of receiving the audio data packet with an audiovisual display (step 416), indicating that the call group can now be occupied if desired by the recipient. [0069]

To occupy the call group following the phone setup, during the hibernation period, that is, in the case of the previous receiving mobile station, receiving the end-of-sending message and another voice data packet from another party, as in step 214. Any participant presses the PTT button 44 after the advance reception and, in the case of the earlier transmission / reception mobile station, after the user releases the talk button and before receiving the voice data packet from another party. .. [0070]

Again, in FIG. 7, when the mobile station 8 detects that the PTT button is pressed in this hibernation state, the mobile station 8 sends a telephone occupancy request to the packet handler 48 (step 216). The call group ID held in the current call group ID record in the mobile station 8 is automatically included in the telephone occupancy request message by the mobile station. Therefore, the user does not need to re-identify the call group of the currently participating telephone. [0071]

If the phone occupancy confirmation is not received from the packet handler 48 within the timeout period set in the mobile station 8, the mobile station 8 attempts to occupy the phone again at a later stage by sending another phone occupancy request. become. [0072]

Upon receiving a phone occupancy confirmation message from the packet handler 48 (step 218), the user is given an audiovisual display of success, after which the user speaks to the microphone 24 of mobile station 8 while holding down the PTT button. His voice can be sent to all current call group participants. [0073]

In Figure 10, when a phone occupancy request is received (step 500), whether another participant in the phone has the current occupancy of the call group, as indicated by the phone occupancy flag held in field 64 of the call group record. Packet handler 48 queries PUD52 to determine (step 502). If the phone occupancy flag does not appear in the call group record, packet handler 48 sends a phone occupancy confirmation message to the caller of the phone occupancy request (step 504) to accommodate the caller in the call group record held in the PUD. Add a phone occupancy flag to field 64 to do (step 506). [0074]

In FIG. 11, when the user who is currently entering the telephone receives an end-of-participation request from the mobile station (step 600), the packet handler 48 records the record held in the PUD 52 for the originator of the end-of-participation request. Remove the call group ID from the current call group field 70 (step 602). [0075]

Then, if only one participant remains on the phone (step 604), the last remaining participant is sent a call termination message (step 606) and the last participant with the call group ID held in PUD52. Remove from the current call group field in the record (step 608). The record of the unusable recipient is also deleted from the telephone copy table in the PUD, and the voice data packet stored in the packet recording device 50 for the call group is deleted. [0076]

FIG. 12 illustrates another embodiment of the mobile station 700 according to the present invention. The mobile station 700 has the components described in relation to the mobile station embodiment shown in FIG. These components are quoted with the same number and share the functionality described in connection with Mobile Station 8. [0077]

Therefore, the mobile station 700 can make a GPRS virtual connection voice call as described in connection with FIGS. 2 to 11 by the user operating the keypad 32 and the PTT button 34. In addition, the mobile station 700 can operate in video conferencing mode. [0078]

The mobile station 700 has an LCD type display 702 capable of displaying still and video instead of the alphanumeric display 30 of the mobile station 8. In addition, the mobile station 700 has a CCD camera 704 capable of capturing still and / or video and a video data codec capable of encoding and decoding still and / video using well-known static and / video coding techniques such as Jpeg and / or Mpeg4. Has a 706. [0079]

Since the video data codec 706 works with the GPRS module 19, video data can be packetized, depacketized, and transferred via the GPRS wireless interface. [0080] [0080]

The mobile station 700 interacts with the system described in relation to FIG. 2, in particular the packet handler 48, in the same manner as described in relation to each of FIGS. 6-11. Therefore, the packet handler can not only form a virtual audio data connection for a two-way call or a group outbound call, but also a virtual video data connection. The dynamic bandwidth allocation functionality provided by GPRS is captured by the camcorder 704 and at a rate sufficient to transmit the video data encoded in the video data codec 706 via the GPRS wireless interface. Enables the transmission of data. [0081]

In Figure 7, when using the mobile station 700 in video conferencing mode, the mobile station sets up and captures a video call and sends video and audio data for reception by one or more call group participants to the PLMN. Follow the steps above. In this regard, in step 208 described above in connection with FIG. 7, in addition to picking up audio data on the microphone 24 and converting that data to the audio codec 20, receiving video data on the camcorder 704 and its data. There is a conversion to the video codec 706. On the other hand, even if the PTT button 34 is still activated, step 210 involves transmitting both audio and video data in either individual data packets or the same data packet. In this regard, this is called the "PTT" button, but shall include a "push to send audio and video" button. [0082]

In another mode, the video data with the audio data in step 210 is still video data captured by the camera 704 and encoded by the video data codec 706. [0083]

In yet another mode, the mobile station 700 is configured to independently transmit video data, which is video or still video data, in step 210. [0084]

The specific mode used within the mobile station 700 can be selected by the user of the mobile station by interacting with a man-machine interface, such as the keypad 32. [0085]

In FIG. 8, the packet handler 48 can perform the procedure described above to receive and respond to a phone configuration request for a video and / or audio call. In this regard, in step 312, the packet handler receives a video data packet and / or an audio data packet while the recipient occupies the telephone. The packet handler 48 explicitly processes the packet, regardless of the contents of the received data packet. [0086]

In FIG. 9, the mobile station 700 can receive phone setting messages for both video and audio calls and can tolerate the same thing. In this regard, in step 410, the data packets received via the GPRS wireless interface include video and / audio data packets, and step 412 converts those data packets to a video data codec and / or audio codec, video and /. Or with the output of the audio signal to display 702 and / or by loudspeaker 22. [0087]

Therefore, embodiments of the present invention provide methods and devices for making half-duplex video conferencing calls either between two parties or between groups of telephone participants in outgoing mode. It is advantageous in that video data requiring a relatively large amount of bandwidth is transmitted in only one direction at a time, and is intermittent only when the user of the system wants to transmit the video data. Furthermore, the power specification conditions of mobile stations are relatively low. This is in contrast to the conventional concept of video conferencing calls, which constantly transmit video data in full-duplex mode. [0088]

It goes without saying that various modifications and equivalents may be used in connection with the above embodiments, without departing from the scope of the present invention. [0089]

The mobile station 700 embodiment described above can operate in both GPRS virtual connection mode and conventional circuit exchange mode. Other embodiments of the invention include mobile stations that can only operate in the GPRS virtual connection mode of the invention. [0090]

The GPRS virtual connection mode described above in connection with the two embodiments of the present invention is inherently half-duplex unless only one party to the telephone can transmit audio and / or video data at one time. However, GPRS can send and receive data packets at the same time via the wireless interface, so in the case of a two-way call, audio and / video data transfer will occur at the same time to make a full-duplex virtual connection. In this case, neither party "occupies" the call group and neither party is prevented from transmitting audio and / or video data when receiving such data. [0091]

In the above embodiment, the GGSN44 sends a logon and logoff message to the packet handler 48 when the subscriber receives or exits the GPRS service. Other signal feed procedures are also possible. For example, when receiving a telephone configuration request, the packet handler 48 can query the HLR and / or GGSN44 to find out the current status of potential telephone participants. Logon / logoff messages can also be sent from HLR12 to packet handler 48 instead of from GGSN44. [0092]

In the embodiment described above, the control message passing between the mobile station and the packet handler 48 has a call group ID that is considered to be contrasted with the call group record. In the case of a two-way call, replace such a call group ID with a single recipient ID, which is a single recipient record in PUD52. [0093]

In the above case, the packet data network 46 is called an external packet data network. The packet data network 46 is'external'as long as it exceeds the GGSN44, but is under the ownership and control of the PLMN operator. Therefore, it (packet data network) can form part of an intranet, etc., and can also take the form of a single mechanical link between the GGSN44 and the packet handler 48. The functionality of Packet Handler 48 can also be integrated with the functionality of GGSN44. [0094]

In the above description, the packet handler controls the virtual connection between mobile stations operating in the same PLMN. As shown in Figure 3, another PLMN GGSN56 can be accessed from the packet handler via the packet data network 46. Therefore, packet handlers are used to set up virtual connections between mobile stations operating within the illustrated PLMN and mobile stations operating within other PLMNs, including GPRS mission-critical telecommunications equipment. Further, the packet handler 48 can also control a virtual connection between the mobile station operating in the illustrated PLMN and a fixed terminal, for example, the fixed terminal 58 shown in FIG. 3 connected to the packet data network 46. [0095]

In the above embodiment, the occupancy of the call group and the period during which the mobile station transmits audio and / or video data are determined by manually pressing the PTT button 36. Other man-machine interface dialogues are also used to determine the period for which the telephone occupancy operation and the mobile terminal transmit audio or video data, for example, the operation and period are voice driven. [0096]

In the above embodiment, the packet storage device 50 holds a data packet received during a virtual telephone connection of a potential telephone recipient. Further, the packet storage device is used to hold the voice mail message and the data message received via the GPRS service, and the voice mail message and the data message are transmitted to the other party via the GPRS service. Further, the packet storage device 50 receives information transmitted to the user station via the GPRS service upon request, such as stock price information, news, weather, etc. provided as text information, still image information, audio and / or video information. Information can be retained. [0097]

Consider an embodiment of a mobile terminal other than the handset described. For example, the mobile terminal can be a car phone composed of a GPRS enable hardware unit installed in a vehicle and a handheld microphone / pushtalk unit connected to the hardware unit via a wiring cord. [0098]

In the above case, the transfer of audio and video data in the half-duplex communication mode will be described. The data packet transferred by the packet handler 48 between the user stations also forms a text message (short message) transmitted in the telephone environment or in the telephone-independent environment. [0099]

Preferably, the forwarding of text messages is not limited to the packet handler 48, which identifies the available recipients and recipient addresses from the PUD52 for forwarded text messages and for the unavailable recipients. Useful for storing messages in the packet storage device 50 of. [0100]

Here, the GSM type system will be described. This system is at least partially based on the GSM system defined in the GSM Technical Specification published by the European Telecommunications Standards Institute (ETSI), such as the DCS1800 system, PCS1900 system and GSM. Includes third generation systems (eg UMTS). [0101]

It is conceivable that modifications and modifications to the above embodiments will be adopted without departing from the scope of the invention as set forth in the appended claims.

[Simple explanation of drawings]

[Figure 1]

It is a schematic block diagram of a well-known public ground mobile network. [Figure 2]

It is a schematic block diagram of the mobile station according to the 1st Embodiment of this invention. [Fig. 3]

It is a schematic block diagram of the mobile communication network arranged by this invention. [Fig. 4]

It is a schematic diagram of the telephone group record used in connection with the embodiment of this invention. [Fig. 5]

It is a schematic diagram of the mobile subscriber recording storage device related to the embodiment of the present invention. [Fig. 6]

It is a flow diagram which illustrates the technique performed by the mobile station by embodiment of this invention. [Fig. 7]

It is a flow diagram which illustrates the technique performed by the mobile station by embodiment of this invention. [Fig. 8]

It is a flow diagram which illustrates the method executed by the data packet handler by embodiment of this invention. [Fig. 9]

It is a flow diagram which illustrates the technique performed by the mobile station by embodiment of this invention. [Fig. 10]

It is a flow diagram which illustrates the method executed by the data packet handler by embodiment of this invention. [Fig. 11]

It is a flow diagram which illustrates the method executed by the data packet handler by embodiment of this invention. [Fig. 12]

It is a schematic block diagram of the 2nd Embodiment of the mobile station by this invention.