Mobile radio communication system

Abstract

A mobile radio communication system having a mobile radio communication network and a mobile radio subscriber appliance, wherein a unit in the network layer of the core network of the mobile radio communication network is configured to transmit to the mobile radio subscriber appliance a first message, based on an occurrence of a predetermined event, with a request for a statement which describes at least one radio characteristic of the mobile radio subscriber appliance.

Claims

1. One or more non-transitory, computer-readable media having instructions that, when executed by one or more processors, cause an apparatus to: identify a request for inter-system handover information received in a routing area update accept message; generate a routing area update complete message to include an information element to include the requested inter-system handover information; and cause the routing area update complete message to be transmitted to a network, wherein the information element includes an inter-radio access technology (RAT) information container that includes predefined configuration information or radio capability information about a mobile device.

2. The one or more non-transitory, computer-readable media of claim 1, wherein the inter-RAT information container includes the predefined configuration information about the mobile device.

3. The one or more non-transitory, computer-readable media of claim 1, wherein the inter-RAT information container includes security information.

4. The one or more non-transitory, computer-readable media of claim 3, wherein the security information includes a START PS value.

5. The one or more non-transitory, computer-readable media of claim 1, wherein the inter-RAT information container includes the radio capability information.

6. The one or more non-transitory, computer-readable media of claim 1, wherein the information element is a type 4 information element with a minimum length of three octets.

7. The one or more non-transitory, computer-readable media of claim 6, wherein the information element has a maximum length of 40 octets.

8. A method comprising: identifying a request for inter-system handover information received in a routing area update accept message; generating a routing area update complete message to include an information element to include the requested inter-system handover information; and causing the routing area update complete message to be transmitted to a network, wherein the information element includes an inter-radio access technology (RAT) information container that includes predefined configuration information or radio capability information about a mobile device.

9. The method of claim 8, wherein the inter-RAT information container includes the predefined configuration information about the mobile device.

10. The method of claim 8, wherein the inter-RAT information container includes security information.

11. The method of claim 10, wherein the security information includes a START PS value.

12. The method of claim 8, wherein the inter-RAT information container includes the radio capability information.

13. The method of claim 8, wherein the information element is a type 4 information element with a minimum length of three octets.

14. The method of claim 13, wherein the information element has a maximum length of 40 octets.

15. One or more non-transitory, computer-readable media having instructions that, when executed by one or more processors, cause a device to: generate a routing area update accept message to include a request for inter-system handover information; cause the routing area update accept message to be transmitted to a mobile radio subscriber appliance; and identify, in a routing area update complete message received from the mobile radio subscriber appliance, an information element that includes the requested inter-system handover information, wherein the information element includes an inter-radio access technology (RAT) information container that includes predefined configuration information or radio capability information about a mobile device.

16. The one or more non-transitory, computer-readable media of claim 15, wherein the instructions, when executed, further cause the device to: perform one or more handover operations based on the inter-system handover information.

17. The one or more non-transitory, computer-readable media of claim 15, wherein the inter-RAT information container includes the predefined configuration information about the mobile device.

18. The one or more non-transitory, computer-readable media of claim 15, wherein the inter-RAT information container includes security information.

19. The one or more non-transitory, computer-readable media of claim 18, wherein the security information includes a START PS value.

20. The one or more non-transitory, computer-readable media of claim 15, wherein the inter-RAT information container includes the radio capability information about the mobile device.

21. The one or more non-transitory, computer-readable media of claim 15, wherein the information element is a type 4 information element with a minimum length of three octets.

22. A method comprising: generating a routing area update accept message to include a request for inter-system handover information; causing the routing area update accept message to be transmitted to a mobile radio subscriber appliance; and identifying, in a routing area update complete message received from the mobile radio subscriber appliance, an information element that includes the requested inter-system handover information, wherein the information element includes an inter-radio access technology (RAT) information container that includes predefined configuration information or radio capability information about a mobile device.

23. The method of claim 22, further comprising: performing one or more handover operations based on the inter-system handover information.

24. The method of claim 22, wherein the inter-RAT information container includes the predefined configuration information about the mobile device.

25. The method of claim 22, wherein the information element includes security information.

26. The method of claim 25, wherein the security information includes a START PS value.

27. The method of claim 22, wherein the inter-RAT information container includes the radio capability information about the mobile device.

28. The method of claim 22, wherein the information element is a type 4 information element with a minimum length of three octets.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The use of the same reference number in different instances in the description and the figures may indicate similar or identical items.

(2) FIG. 1 shows a communication system based on an exemplary embodiment of the invention.

(3) FIG. 2 shows a message flowchart based on an exemplary embodiment of the invention.

(4) FIG. 3 shows Table 1 illustrating an information element based on an exemplary embodiment.

(5) FIG. 4 shows Table 2 illustrating an inter-RAT information container based on an exemplary embodiment.

DETAILED DESCRIPTION

(6) FIG. 1 shows a communication system 100 based on an exemplary embodiment of the invention.

(7) The communication system 100 has a GSM (Global System for Mobile Communications) mobile radio network 101 and a UMTS (Universal Mobile Telecommunication System) mobile radio network 102.

(8) A mobile radio subscriber appliance 103 is both GSM compatible and UMTS compatible. That is to say that the mobile radio subscriber appliance 103 can set up radio communication links to the GSM mobile radio network 101 and can set up radio communication links to the UMTS mobile radio network 102.

(9) When a radio communication link has been set up between the mobile radio subscriber appliance 103 and the GSM mobile radio network, it is provided by the GSM mobile radio network using a BTS (Base Transceiver Station) 104, a base station in the GSM mobile radio network 101. The BTS 104 is coupled to a BSC (Base Station Controller) 105 and is managed by it. The BTS 104 and the BSC 105 are part of the GERAN (GSM Edge Radio Access Network; EDGE: Enhanced Data Rate for GSM Evolution) 106 of the GSM mobile radio network 101. The GERAN 106 is the radio access network of the GSM mobile radio network 101.

(10) So that the GSM mobile radio network 101 is able to provide, in particular, packet-switched communication links and packet-switched communication services, for example data transfers to and from the Internet 108, the BSC 105 is coupled to a first SGSN (Serving GPRS Support Node) 107. The first SGSN 107 is coupled to a first GGSN (Gateway GPRS Support Node) 109, which is coupled to the Internet 108 and has the functionality of a gateway.

(11) The first SGSN 107 and the first GGSN 109 are part of the core network 110 of the GSM mobile radio network 101.

(12) When a radio communication link has been set up between the mobile radio subscriber appliance 103 and the UMTS mobile radio network 102, it is provided by means of a NodeB 111, a UMTS base station. The NodeB 111 is managed by an RNC (Radio Network Controller) 112. So that the UMTS mobile radio network 102 is able to provide packet-switched communication links and packet-switched communication services, for example data transfers to and from the Internet 108, the RNC 112 is coupled to a second SGSN 113. The second SGSN 113 is coupled to a second GGSN 114, which in similar fashion to the first GGSN 109 has the functionality of a gateway and is coupled to the Internet 108.

(13) The NodeB 111 and the RNC 112 are part of the UTRAN (Universal Terrestrial Radio Access Network) 115 in the UMTS mobile radio network 102. The UTRAN 115 is the radio access network of the UMTS mobile radio network 102.

(14) The second SGSN 113 and the second GGSN 114 are part of the core network 116 of the UMTS mobile radio network 102.

(15) The first SGSN 107 and the second SGSN 113 are coupled to one another. In one embodiment, the first SGSN 107 and the second SGSN 113 are one and the same SGSN (shared SGSN).

(16) When a packet-switched communication link has been set up from the mobile radio subscriber appliance 103 to the Internet 108, for example, using a radio communication link to the GSM mobile radio network 101, it is possible, if the mobile radio subscriber appliance 103 is in the domain of the UMTS mobile radio network 102, to clear down the radio communication link to the GSM mobile radio network 101, and the packet-switched communication link can be extended to the UMTS mobile radio network 102 using a radio communication link which has just been set up. That is to say that it is possible to perform inter-system handover of the packet-switched communication link from the GSM mobile radio network 101 to the UMTS mobile radio network 102, or in other words inter-system handover of the packet-switched communication link from the GERAN 106 to the UTRAN 115.

(17) To be able to perform such inter-system handover, however, it is necessary for the RNC 112 to have information specific to the mobile radio subscriber appliance 103. By way of example, as in 3GPP TS 25,331; 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Radio Resource Control (RRC); Protocol Specification (Release 5), section 10.3.3.42, this information is:

(18) TABLE-US-00001 Information Element/ Type and Semantics Group name Need reference description Access stratum MP Enumerated Indicates the release release indicator (R99) of the UE according to [35]. The IE also indicates the release of the RRC transfer syntax supported by the UE CV- Enumerated 13 spare values are not_rr (REL-4, needed. c_conn ection REL-5 SetupC complete REL-6) DL capability with OP Enumerated simultaneous HS- (32 kbps) DSCH configuration 64 kbps, 128 kbps, 384 kbps) PDCP capability MP PDCP capability 10.3.3.24 RLC capability MP RLC capability 10.3.3.34 Transport channel MP Transport capability channel capability 10.3.3.40 RF capability FDD OP RF capability FDD 10.3.3.33 RF capability TDD OP RF capability One TDD RF TDD 10.3.3.33b capability entity shall be included for every Chip rate capability supported Physical channel MP Physical capability channel capability 10.3.3.25 UE multi-mode/multi- MP UE multi- RAT capability mode/multi-RAT capability 10.3.3.41 Securing capability MP Security capability 10.3.3.37 UE positioning MP UE positioning capability capability 10.3.3.45 Measurement CH- Measurement capability fdd_re q_sup capability 10.3.3.21

(19) This information is subsequently called the required information (for inter-system handover).

(20) In the case of the exemplary embodiment explained below, the information specific to the mobile radio subscriber appliance 201 which the RNC 205 needs to know for inter-system handover between the GERAN 106 and UTRAN 115 is transmitted as part of a GPRS Attach to the first SGSN 203 and is forwarded from there to the RNC 205.

(21) FIG. 2 shows a message flowchart 200 based on an exemplary embodiment of the invention.

(22) The message flow shown takes place between a mobile radio subscriber appliance 201, a BSC 202, a first SGSN 203, a second SGSN 204 and an RNC 205, which are arranged and in form explained with reference to FIG. 1.

(23) It is assumed that a first radio communication link has been set up from the mobile radio subscriber appliance 201 to the GSM mobile radio network 101.

(24) In step 206, the mobile radio subscriber appliance 201 transmits an Attach Request message 220 to the first SGSN 203, which message contains the request for a GPRS Attach for the mobile radio subscriber appliance 201, that is to say registration of the mobile radio subscriber appliance 201 at the first SGSN 203.

(25) The Attach Request message 220 is a conventional Attach Request message for requesting a GPRS Attach and is in form described in 3GPP TS 24.008 V6.7.0; 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 6), for example.

(26) It is assumed that the GPRS Attach for the mobile radio subscriber appliance 201 is successful at the first SGSN 203.

(27) The first SGSN 203 decides whether to request the required information from the mobile radio subscriber appliance 201. By way of example, the first SGSN 203 can decide to request the required information from the mobile radio subscriber appliance 201 if the GSM mobile radio network 101 supports packet-switched inter-system handover, that is to say inter-system handover of a packet-switched communication link or of a packet-switched communication service to the UMTS mobile radio network. If the GSM mobile radio network 101 does not support packet-switched inter-system handover to the UMTS mobile radio network 102, then the first SGSN 107 will decide not to request the required information from the mobile radio subscriber appliance 201. In this example, however, it is assumed that the GSM mobile radio network 101 does support packet-switched inter-system handover to the UMTS mobile radio network 102.

(28) The first SGSN 203 may also decide, by way of example, to request the required information from the mobile radio subscriber appliance 201 if the mobile radio subscriber appliance 201 is in a geographical area in which both the GSM mobile radio network 101 and the UNITS mobile radio network 102 can be used using the mobile radio subscriber appliance 103.

(29) In this example, it is assumed that the first SGSN 203 decides to request the required information from the mobile radio subscriber appliance 201.

(30) In step 207, the first SGSN 203 transmits an Attach Accept message 221 to the mobile radio subscriber appliance 201, The first SGSN 203 uses the Attach Accept message 221 to acknowledge to the mobile radio subscriber appliance 201 that the GPRS Attach for the mobile radio subscriber appliance 201 has been successful. In addition, the Attach Accept message 221 contains the request to the mobile radio subscriber appliance 201 for transmission of the required information to the first SGSN 203.

(31) By way of example, the Attach Accept message 221 is in form explained in 3GPP TS 24,008 V6.7.0; 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 6), but additionally has the specification that the mobile radio subscriber appliance 201 needs to transmit the required information to the first SGSN 203.

(32) To this end, the Attach Accept message 221 may contain, by way of example, an information element (IE) which is in form shown in table 1 of FIG. 3 in accordance with some embodiments.

(33) In this context, the value 0 of the parameter UE-RAC indicates that the required information is not being requested, and the value 1 of the parameter UE-RAC indicates that the required information is being requested.

(34) In step 208, the mobile radio subscriber appliance 201 transmits to the first SGSN 203 an Attach Complete message 222, which is in similar form to the Attach Complete message described in 3GPP TS 24.008 V6.7.0; 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 6), but additionally has an inter-RAT information container containing the required information.

(35) In this embodiment, the inter-RAT information container is an information element of type 4 based on GPP with a minimum length of 3 octets. The limitation of the maximum length is given by the maximum number of octets in an L3 message based on 3 GPP, see 3GPP TS 44.006; 3.sup.rd Generation Partnership Project; Technical Specification Group GSM EDGE Radio Access Network; Mobile Station Base Station System (MS-BSS) interface; Data Link (DL) layer specification (Release 5). The inter-RAT information container is in form shown in table 2 of FIG. 4 in accordance with some embodiments.

(36) The value portion (see line 3 of table 2) of the inter-RAT information container is the inter-RAT Handover info as defined in 3GPP TS 25.331; 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Radio Resource Control (RRC); Protocol Specification (Release 5).

(37) The inter-RAT information container contains the required information. The inter-RAT information container may also contain security information, for example a START PS value, that is to say an input parameter for the encryption method used, which parameter is intended to be used after inter-system handover. The inter-RAT information container may also contain further information, for example prescribed configuration information.

(38) The first SGSN 203 stores the required information transmitted to it.

(39) It is assumed that following the successful GPRS Attach from the mobile radio subscriber appliance 201 to the Internet 108 a packet-switched communication link is set up. When setting up the communication link, the SGSN 203 transmits the required information to the BSC 202 in step 209.

(40) It is also assumed that the mobile radio subscriber appliance 201 is in the domain of a UMTS radio cell of the UMTS mobile radio network 102 in step 210, for example the user of the mobile radio subscriber appliance 201 has taken the mobile radio subscriber appliance 201 into a UMTS radio cell of the UMTS mobile radio network 102. The mobile radio subscriber appliance 201 performs radio measurements and measures the reception quality of the UMTS mobile radio network 102 and of the GSM mobile radio network 101 and notifies the BSC 202 of the measurement results.

(41) In step 211, the BSC 202 takes into account the required information in deciding that the packet-switched communication link which was set up at the first SGSN 203 after the GPRS Attach for the mobile radio subscriber appliance 201 now needs to be extended using the UMTS mobile radio network 102, that is to say that a new packet-switched communication link to the Internet 108 needs to be provided using the UMTS mobile radio network 102, and the packet-switched communication link using the GSM mobile radio network needs to be cleared down.

(42) It is thus necessary to perform inter-system handover of the packet-switched communication link from the GSM mobile radio network 101 to the UMTS mobile radio network 102.

(43) By way of example, a decision is made that the packet-switched communication link to the Internet 108 now needs to be provided using the UMTS mobile radio network 102, since in this way a higher data transmission rate is possible than when using the GSM mobile radio network 101. The movement of the mobile radio subscriber appliance 103 may also mean that the reception quality of the GSM mobile radio network 101 has become so poor that the measurement results of the radio measurements are taken as a basis for deciding that inter-system handover to the UMTS mobile radio network 102 needs to be performed. In addition, it is possible That the user of the mobile radio subscriber appliance 201 wishes to use a communication service which can be provided only using the UMTS mobile radio network 102.

(44) On the basis of the decision that inter-system handover needs to be performed, the BSC 202 sends a first handover request message 223 to the SGSN 203, which is used to request inter-system handover of the existing packet-switched communication link from the GSM mobile radio network 101 to the UMTS mobile radio network 102.

(45) In step 212, the SGSN 203 sends a second handover request message 224 to the RNC 205, which is used to ask the RNC 205 to make the necessary preparations for the inter-system handover.

(46) In particular, a second radio communication link needs to be set up from the mobile radio subscriber appliance 201 to the UMTS mobile radio network 102, so that the packet-switched communication link can in the future be provided by means of the second SGSN 113 and the UMTS mobile radio network 102.

(47) It is assumed that a decision is made that the second radio communication link needs to be cleared down using the NodeB 111 (for example because the mobile radio subscriber appliance has moved into the domain of the NodeB 111).

(48) The second handover request message 224 contains the required information, which is transmitted to the RNC 205 in this way.

(49) In step 213, the second RNC 205 takes into account the required information in reserving radio resources for the second radio communication link and acknowledges the second handover request message 224 using a first acknowledgement message 225.

(50) In step 214, the first SGSN 203 sends a first Handover Command message 226 to the BSC 202. The BSC 202, for its part, transmits a second Handover Command message 227 to the mobile radio subscriber appliance 201 in step 215.

(51) In step 218, the mobile radio subscriber appliance transmits a Handover Complete message 228 to the RNC 205 in order to acknowledge that it is now using the second radio communication link for the data transmission.

(52) In the embodiment described, the required information is requested by the first SGSN 203 as part of the GPRS Attach for the mobile radio subscriber appliance 201 (Attach Accept message 221), and the required information is also transmitted to the first SGSN 203 as part of the GPRS Attach (Attach Complete message 222).

(53) In another embodiment, the required information is requested and transmitted as part of a Routing Area Update. In a similar fashion to the Attach Request message 220, the mobile radio subscriber appliance 201 transmits a Routing Area Update Request message as part of a Routing Area Update procedure. This is described in 3GPP TS 24.008 V6.7.0; 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 6). The first SGSN 203 responds to the Routing Area Update Request message with a Routing Area Update Accept message, which is essentially in a form as in 3GPP TS 24.008 V6.7.0; 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 6), but in this embodiment contains the request to the mobile radio subscriber appliance 201 to transmit the required information to the first SGSN 203.

(54) The mobile radio subscriber appliance 201 then responds with a Routing Area Update Complete message, which is in the form described in 3GPP TS 24.008 V6.7.0; 3rd Generation Partnership Project; Technical Specification Group Core Network; Mobile radio interface Layer 3 specification; Core network protocols; Stage 3 (Release 6) but additionally contains the required information.

(55) In other embodiments, a hybrid form of the procedures described above is used for requesting and transmitting the required information. By way of example, the first SGSN 203 requests transmission of the required information from the mobile radio subscriber appliance using a Routing Area Accept message, and the mobile radio subscriber appliance 201 transmits the required information as part of a GPRS Attach using a Routing Area Update Complete message.

(56) In addition to the required information being requested and transmitted as part of a registration signaling procedure such as a Routing Area Update and a GPRS Attach, the required information may also be requested and transmitted as part of a different procedure. By way of example, one embodiment defines a new GMM (GPRS Mobility Management) procedure in comparison with the prior art, which procedure involves the required information being requested by the first SGSN 203 and being transmitted from the mobile radio subscriber appliance 201 to the first SGSN 203.

(57) This new GMM procedure is carried out when a predetermined event occurs or when a predetermined criterion has been met. An example of a predetermined event of this type is when the mobile radio subscriber appliance 201 moves into a geographical area in which both the GSM mobile radio network 101 and the UMTS mobile radio network 102 are available, that is to say that radio communication links can be set up both to the GSM mobile radio network 101 and to the UMTS mobile radio network 102.

(58) In one embodiment, the mobile radio subscriber appliance receives signaling determining whether the GSM mobile radio network 101 supports inter-system handover to the UMTS mobile radio network 102.

(59) By way of example, this is done using an Information Request message containing an information element (IE), for example, which is in the form shown in table 1. The mobile radio subscriber appliance then transmits in an Information Provision message which has an inter-RAT information container containing the required information.

(60) In this embodiment, the inter-RAT information container is an information element of type 4 based on GPP with a minimum length of 3 octets. The limitation of the maximum length is given by the maximum number of octets in an L3 message based on 3 GPP, see 3GPP TS 44.006; 3rd Generation Partnership Project; Technical Specification Group GSM EDGE Radio Access Network; Mobile Station-Base Station System (MS-BSS) interface; Data Link (DL) layer specification (Release 6). The inter-RAT information container is in the form shown in table 2.