MXPA01002088A - Cdma transmission of packet-switched data - Google Patents

Abstract

A method for conveying packet data from a CDMA mobile station (40) to a GSM network (22), including communicating with a GSM service node to establish a data link from the mobile station (40) to the network (22) via a radio communications base station (32). The packet data are conveyed between the mobile station (40) and the base station (32) over a CDMA air interface and are then transferred over the link between the base station (32) and the network (22).

Description

MULTIPLE ACCESS TRANSMISSION WITH DIVISION OF DATA CODE SWITCHED IN PACKAGES • FIELD OF THE INVENTION 5 The present invention relates generally to wireless telecommunications, and specifically to the transmission of data over advanced cellular communications networks.

BACKGROUND OF THE INVENTION The Global System for Mobile Telecommunications (GSM) is used in cellular telephone networks in many countries around the world. GSM offers a useful range of network services and standards, including facilities for data transmission, as well as voice. Existing GSM networks are based on Time Division Multiple Access (TDMA) digital telecommunications technology. 20 Multiple access with code division (CDMA) is an enhanced digital communications technology, which provides more efficient use of TDMA radio bandwidth, as well as a more reliable, fading-free link between subscribers of cell phones and base stations. The leading CDMA standard is IS-95, promulgated by the Telecommunications Industry Association (TIA). The PCT patent application, PCT / US96 / 20764, which is incorporated herein by reference, discloses a wireless telecommunications system that utilizes a CDMA air interface or interconnect (e.g., basic RF communications protocols) for implement GSM network services and protocols. Using this system, at least some of the TDMA base stations (BSSs) and subscriber units of an existing GSM network would be replaced or supplemented by the corresponding CDMA equipment. The CDMA BSSs in this system are adapted to communicate with the GSM mobile switching centers (MSCs) via an interconnection with GSM the core of the GSM network services is thus maintained, and the change from TDMA to CDMA is transparent for users. Hybrid cellular telecommunications networks, which incorporate elements of GSM and CDMA are also described in PCT patent publications WO 95/24771 and WO 96/21999, and in an article by Tscha, et al., Entitled "A Subscriber Signaling Gateway between CDMA Mobile Station and GSM Mobile Switching Center ", in Proceedings of the 2nd International Conference on Universal Personal Communications Ottawa 81993), page 181-185, which are incorporated by reference herein. None of these publications has to do with the specific problems of data communications. Such problems include the need for protocol compatibility and the different demands of data voice communications. Although TIA has promulgated CDMA air data transmission standards, such as IS-657 and IS-707, the GSM BSS-MSC interconnection is not adequate to support such transmission. Generally speaking, because GSM was developed primarily for circuit-switched transmission, it is not very suitable for packet-switched data, as is commonly transmitted over the Internet. For this reason, the European Institute of Telecommunications Standards (ETSI) has proposed a general packet data service (GPRS) to operate in conjunction with the GSM cellular network. GPRS is described in a number of GSM standards including 02.60, 03.60 and 03.64, which are incorporated by reference herein. When a subscriber unit (or mobile station MS) in a GSM network with GPRS wishes to send and / or receive data switched in packets, the MS through the BSS with which it is in communication, makes contact with a "node of GPRS service support " (SGSN), on a Gb interconnection of the GSM standard.

The data is transmitted and received by the BSS through the SGSN, separately from the voice channels that go through the MSC, to a data network in • packages (PDN), such as the Internet. The SGSN likewise maintains its own separate mobility management and its security facilities. Contrary to GSM-TDMA voice communications, GPRS allows the dynamic allocation of time interval in the air interconnection between the subscriber units and the SGSN. • SUMMARY OF THE INVENTION An object of the present invention is to provide methods and apparatus for transferring packet-switched data through a cellular communications network. In some aspects of the present invention, the data is transported over a CDMA air interconnect. In other aspects of the present invention, the data is transported in the network in accordance with GSM standards, and particularly with the proposed GPRS standard. In the preferred embodiments of the present invention, a mixed GSM / CDMA cellular communications system includes one or more CDMA base stations (BSSs), controlled by a GSM mobile switching center (MSC). Systems of this type are described in the United States patent application entitled "Delivery of Base Station in a Hybrid GSM / CDMA Network", filed on July 20, 1998, • which is assigned to the assignee of the present patent application and is incorporated by reference 5 herein. A subscriber unit in the system, referred to herein as a mobile station (MS), which is in communication with one of the CDMA BSSs over a CDMA air interconnect, transmits and receives packet switched data ™ 10 to through the system via the CDMA BSSs. The MS and CDMA BSS are adapted to operate substantially in accordance with the GSM data network and the signaling protocols. The data transmitted and received by the MS includes preferably the Internet protocol data (IP), but other types of data can similarly ^ be transported. The term "data" as used in the context of the present patent application and in the claims, refers substantially to All types of data are typically transferred through packet switched networks, which may even include voice transmission, as is known in the art. In some preferred embodiments of the In this invention, the system includes a GPRS network, with which the CDMA BSS is communicated, in accordance with the GPRS network and data signaling standards. Preferably, the MS and the CDMA BSS communicate with an SGSN associated with the GPRS network via a standard GSM / GPRS Gb interconnect.

• The transmission of data signaling over a CDMA Um interconnection between the MS and the BSS are adapted to support GSM / GPRS protocols operating on the Gb interconnection, which is substantially unmodified. In other preferred embodiments of the present invention, the CDMA BSS has a direct interconnection to a packet switched network such as the Internet. A network service mode, preferably a service control point (SCP) that works as a specific service node per operator (OSS), is coupled between the GSM MSC and the CDMA BSS. The MSC control or services such as authentication, encryption and ^ billing, preferably through the SCP using an OSS interconnection, for example, the CAMEL interconnection (custom applications for logical augmented mobile network) as it has been proposed by ETSI. There is thus provided, according to a preferred embodiment of the present invention, a method for transporting packet data between a mobile station and a GSM network, which includes: communication with a GSM service node to establish a data link between the mobile station and the network via a radio communications base station; the transfer of data in packets between the mobile station and the base station over a CDMA air interconnection; and the transfer of data on the link between the base station and the network. Preferably, communication with the node includes communication with a GPRS node, and data transfer includes the transfer of data via the GPRS node, where communication with the GPRS node includes communication with SGSN via a Gb interconnection of GSM. Preferably, further, the transfer of the data includes mapping the GPRS frames or structures on CDMA air interconnection, where the mapping of the GPRS data frames includes the use of a link control. CDMA radio to support a logical link control of GPRS. In a preferred embodiment, data transfer includes the transfer of data from a specific GSM operator service, where communication with the node includes communication with a GSM service control point, which communicates with a GSM service control point. switching center via a GSM-specific service interconnection. Preferably, the mobile station communicates with a home location register via a data interconnection of the unstructured GSM supplementary service. Alternatively, the service control point communicates with a switching center via the GSM custom applications enhanced logical connection of the mobile network. Preferably, the method includes changing the mobile station from the base station to another base station, wherein the transfer of data over the link includes routing the data to the other base station using the mobile IP. Preferably, communication with the service node includes communication with a switching center via a GSM interconnection A. In a preferred embodiment, the transfer of the data includes the transfer of data directly between the base station and the network, substantially without passing the data through the service node. Preferably, communication with the service node includes the provision of GSM authentication of the mobile station for a call made on a CDMA air interconnect. Preferably further, the data transfer includes data transfer over a CDMA air interconnection substantially based on an IS interconnection standard. In a preferred embodiment, data transfer includes data transfer at a variable speed. , which responds to a volume of data that is going to be transported over the air interconnection, where the data transfer preferably includes the opening of a fundamental channel to transfer the data and the signaling on it, and which responds to the volume of data. data that opens one or more supplementary channels between the mobile station and the base station to carry the data. Preferably, the opening of the supplementary channels includes the opening of a different number of channels in the reverse forward directions between the mobile station and the base station. Alternatively or additionally, one or more supplementary channels are closed in response to a decrease in the data rate or rate. Preferably, data transfer includes data transfer using the CDMA packet data service, 'IS-657 is IS-707. There is further provided, according to a preferred embodiment of the present invention, the wireless communication apparatus for use in a mobile telecommunications system, which includes: a mobile station, which is coupled to exchange data with the terminal equipment, and that initiates a call to transfer data over a CDMA air interconnect; and a base station, which communicates with a service node of the GSM network to establish a data link responsive to the call initiated by the mobile station, and which transfers the data between the mobile station and the network over the data link Preferably, the service node includes a GPRS node, and wherein the base station transfers the data via the GPRS node using a GPRS communication protocol, wherein the GPRS node includes an SGSN, with which the base station via a GSM Gb interconnection. In a preferred embodiment, the data is transferred over the data link as a GSM-specific service, wherein the GSM network node preferably includes a GSM service control point, which communicates with a center of switching via an operator-specific service interconnection. Alternatively, the mobile station communicates with a home location register via a data interconnection of the structured supplementary service, GSM. Alternatively, in addition, the service control point communicates with a switching center via one of the custom GSM applications for the improved logical interconnection of the mobile network. Preferably, the data link or link includes a direct connection between the base station and the network, wherein the data is transferred over the direct connection substantially without passing through the service node. Preferably, the air interconnection is substantially based on an air interconnection standard of CDMA, IS-95, and the air interconnection operates substantially in accordance with the packet data service of CDMA, IS-657 and IS-707. The present invention will be more fully understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the drawings in which: BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic block diagram of a GSM / CDMA hybrid cellular communications system, in accordance with a preferred embodiment of the present invention; Figures 2A and 2B are schematic block diagrams illustrating groups of communication protocols between the elements of the system of Figure 1, according to a preferred embodiment of the present invention; Figure 3 is a schematic block diagram of a GSM / CDMA hybrid cellular communications system according to another preferred embodiment of the present invention; Figure 4 is a schematic signaling diagram illustrating communication procedures involving elements of the system of Figure 3, in accordance with a preferred embodiment of the present invention; and Figure 5 is a schematic block diagram of a GSM / CDMA hybrid cellular communications system, according to another preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Reference is now made to FIG. 1, which is a schematic block diagram of a GSM / CDMA hybrid cellular communications system, in accordance with a preferred embodiment of the present invention. The system 20 is built around a public land mobile network (PLMN) 22, which is based on the GSM communications standard, as is known in the art and briefly described separately preceded. The infrastructure for such networks already exists and is widely used in many countries, and the present invention has the advantage of making possible the gradual introduction of the CDMA service in conjunction with such a network, without requiring major changes to the existing infrastructure. PLMN 22 comprises at least one mobile services switching center (MSC) 24, or possibly a number of such centers (although only one MSC is shown here for clarity of illustration), which controls the operations of the network within one area geographical. Among other functions, the MSC 24 is responsible for the registration of location of subscriber units and the change of the subscriber units between the base sections, as well as the link of PLMN 22 to a public switched telephone network (PSTN) and / or the packet data network (PDN) 48 for circuit switched data. The PLMN also comprises a network management or administration center (NMC) 26 and a cellular broadcasting center (CBC) 28. The functions of these elements, as well as other aspects of the system 20 and the details regarding the mobile station ( MS) 40 in the system are further described in the aforementioned US and PCT patent applications. The system 20 includes a plurality of MSs 40, which communicate with the PLMN 22 via a plurality of base station subsystems (BSS) 30 and 32 over a wireless RF link to one or more accepted cellular communication frequencies. The MS 40, which is also known as a subscriber unit, is preferably capable of communicating with the GSM BSS 30, using a standard GSM TDMA communication protocol, and the CDMA BSS 32, using communication methods based on CDMA, described later in this. Although for clarity purposes, only one of each MS 40, BSS 30 of GSM and BSS 32 of CDMA is shown in Figure 1, it will be understood that currently / the system 20 typically comprises a plurality of each of these elements of the system . The GSM BSS 30 and the CDMA BSS 32 communicate with and are controlled by the MSC 24, substantially in accordance with the GSM standards, via the A interconnection of the GSM standard. The signaling and data communications between the BSS 32 and the MSC 24 are further described in the aforementioned US patent application entitled "Base Station Change in a GSM / CDMA Hybrid Network", and in another patent application from United States, presented on the same date entitled "Transmission of switched data in GSM circuit over a CDMA link" '. These applications are assigned to the assignee of the present patent application and are incorporated herein by reference. The BSS 32 is also linked to a network 50 of the general packet data service (GPRS), as proposed by the European Institute of Telecommunications Standards (ETSI). The GPRS includes an SGSN 52, which communicates in the signaling and data transmission plans with the BSS 32. The SGSN effectively takes the place of the MSC 24 when the MS 40 requests to transmit or receive data in packets via the BSS, instead of voice traffic. In accordance with GPRS standards, SGSN 52 communicates with PDN 48 via a "gate GPRS service node" (GGSN) 54. The communication protocols between MS 40, BSS 32 and SGSN 52 are described below with reference to Figures 2A and 2B. The communications between the BSS 32 and the CDMA MS 40 are based on a CDMA radio "air interconnection", which is preferably based on the IS95 standard for CDMA communications, and more preferably in the TIA / EIA version -95-B of the standard. BSS 32 is built around a controller of the base station (BSC) 34, which controls and communicates with a number of transceivers of the base station (BTS) 36. Each BTS transmits radio frequency signals to and receives radio frequency signals from MS 40 when the MS is within a geographic area, or cell, served by the particular BTS. On the other hand, when the MS 40 is inside a cell served by the BSS 30 of the GSM, the MS preferably communicates with the BSS 30 over a GSM / TDMA air interconnect. It will be understood, however, that the principles of the present invention are in general to the communication of data on CDMA air interconnection between MS 40 and CDMA BSS 32 (and thence to SGSN 52); and it is not essential that the MS 40 have the capability of TDMA communications with the GSM BSS 30, as well. In order to sustain these interconnections, the MS 40 comprises the mobile equipment (ME) 42, which preferably includes either two radio transceivers, one configured for the operation of TDMA and one for CDMA, or a simple transceiver which can dynamically switch between TDMA and CDMA. The MS includes the mobile termination (MT), it is supported by the terminal equipment (TE) 46 for the input and output of data, including package data. Preferably, the TE 46 comprises a user terminal, such as a personal computer, which is coupled to accept and send out data via ME / MT 42. In addition, the MS 40 comprises a subscriber identity module (SIM) 44 , in accordance with GSM standards. Figure 2A is a block diagram schematically illustrating the series or groups of protocols used in signaling interconnections between MS 40, BSS 32 of CDMA and SGSN 52, in accordance with a preferred embodiment of the present invention. These interfaces or interconnections make it possible for the MS 40 to communicate with the GSM SGSN 52 over a CDMA air interconnection between the MS and the BSS 32. If and when MS 40 is in communication with SGSN 52 via the BSS 30, of GSM, the groups of protocols are in accordance with the GPRS standards, substantially without modification to them. Regardless of whether the MS 40 is in communication via the CDMA BSS 32 or the GSM BSS 30, the higher level communications between MS 40 and SGSN 52 are preferably conducted using a logical link control layer (LLC), such as it is specified by GSM standard 04.64, which is incorporated by reference herein. This layer provides a reliable, coded logical link, which is independent of the underlying CDMA or TDMA radio protocols, so changes or only minimal changes in GPRS 50 are not required in relation to the GSM standard. Similarly, mobility management functions are preferably supported by a layer of GSM GPRS mobility management protocol and session management (GMM / SM), in accordance with GSM standard 03.60, which is also incorporated by reference in the present. This layer provides functions such as GPRS binding, GPRS debunking, security, routing area update, location update and the activation and deactivation of the packet data protocol (PDP) context as described in the GSM standard. The MS 40 communicates with the CDMA BSS 32 over a CDMA Um interconnection, based on the CDMA IS-95 air interconnection, which is modified to support the GSM and GPRS signaling standards. The CDMA air interconnection between the MS 40 and BSS 32 comprises the CDMA layer 1, which operates in a standard IS-95 protocol, and a GSM-CDMA radio link control (RLC), in which the operation IS-95 is adapted to support the LLC layers of GPRS and GMM / SM above it in the group. The RLC layer includes a medium access medium control (MAC) function associated with the RLC layer, which controls the access signaling (request and granting) for the CDMA radio channels and the mapping of the frames of the radio. GSM LLC data on the physical CDMA channel. From the point of view of the LLC layers of GPRS and GMM / SM above it, the GSM-CDMA RLC preferably emulates the GSM-TDMA RLC as specified in standard 04.64, which is incorporated by reference in the I presented. The upper layers (LLC of GPRS and GMM / SM) are not processed by BSS 32, but rather retransmitted through MS 40 and SGSN 52 for processing in a substantially transparent manner to the following CDMA air interconnect layers.

The CDMA BSS 32 communicates with the SGSN 52 over a substantially unmodified GSM / GPRS Gb interconnect. This interconnection preferably includes GSM bis, the network service and the BSS GPRS protocol layers (BSSGP). The network service and the Ll bis layers are preferably defined according to the GSM standard 08.16, and the BSSGP layer is preferably defined according to the GSM standard 08.18, whose standards are incorporated by reference herein. The BSSGP layer transfers the routing and information related to quality of service (QoS) between BSS 32 (or BSS 30) and SGSN 52. The service layer of the network transports the data units in BSSGP packets (PDUs) , based on the frame relay connection between the BSS and SGSN that can traverse a network of frame relay switching nodes. BSS 32 moves layer 1 of the CDMA and the GSM-CDMA RLC protocols exchanged between the BSS and the MS 40 to an appropriate Ll bis, the network service and the BSSGP protocols for transmission to the SGSN 52, and vice versa., Because the CDMA BSC 34 communicates with the SGSN 52 over the standard Gb interconnect, substantially no modifications are required in the core GPRS 50 in order to make possible the addition of the CDMA BSS 32 to the GPRS network. In addition, GPRS 50 need not be certain that there is any difference in identity between the GSM / TDMA BSS 30 and the CDMA BSS 32 since both communicate. with the SGSN 52 in a substantially identical manner over the interconnection Gb. Figure 2b is a block diagram schematically illustrating the groups of protocols involved in the transmission of data between MS 40 and GGSN 54 via CDMA BSS 32 and SGSN 52, in accordance with a preferred embodiment of the present invention . ME / MT 42 exchanges data with TE 46 via any suitable physical interconnection and the high level network operation protocol known in the art, for example, an Internet protocol (IP) or an X.25 protocol. The network operation protocol is retransmitted through BSS 32, SGSN 52 and GGSN 54 to a corresponding host coupled to PDN 48. Network level transmissions (such as IP and X.25) between the MS 40 and a corresponding retransmission layer in SGSN 52, are supported by a subnet-dependent convergence protocol (SDCP), preferably as specified by GSM standard 04.65, which is incorporated by reference herein. The SNDCP layer maps the upper network operation level map onto the LLC layer of GPRS, which is described hereinabove with reference to Figure 2A. The LLC data packets received by the SGSN 52 from the SM 40 are translated by the SGSN to TCP or UDP packets. TCP is generally used when a reliable data link, such as X.25, is required between MS 40 and GGSN 54; and UDP is used when such reliability is not required, as in IP transmission. TCP and UDP are well known in the art, and are respectively defined, for example, in RFC 793 and RFC 768 of the Internet Engineering Task Force (IETF), the documents of which are incorporated herein by reference. TCP or UDP packets in SGSN 52 are encapsulated by a tunneling protocol layer (GTP) for transmission to GGSN 54, preferably as specified by standard 09.60, which is also incorporated by reference herein. As described above with reference to Figure 2A, the RLC / MAC layer provides reliable support for the transmission of packets in data in the GSM standard, generated by the higher level network operation functions of MS 40 (and SGSN 52) on the air interconnection of CDMA layer 1 between MS 40 and BSS 32. The mapping of the GPRS LLC charts on the physical CDMA channel, as well as the access signaling procedures, are made by the MAC function. BSS 32 uses the BSSGP layer to transfer the information from the RLC / MAC layer to SGSN 52, which translates this information into IP data for transmission to GGSN 54. The lower layers Ll and L2 in SGSN 52 can comprise any communication protocols of data, suitable, known in the art. Although the above communication protocol layers are generally described with reference to the functions required to adapt a signaling and a data stream of the MS 40 for transport to GPRS 50, it will be understood that the same protocol layers are also used for adapt signaling and GPRS 50 data for transport to MS 40 and output by TE 46. The GPRS transmits in this way and receives data to and from TE 36 via ME / MT 42 and BSS 32 as if MS 40 was operating in GSM / TDMA mode, substantially regardless of the fact that the data transported between the BSS and the MS are encoded by CDMA. In a preferred embodiment of the present invention, when a data rate or ratio between TE 46 and ME / mT 42 exceeds the CDMA traffic channel rates, a feature of IS-95 known as the average data rate transmission ( MDR) is used to accommodate excess data, under the control of the MAC function described hereinabove. In this case, MS 40 and BSS 32 open multiple traffic channels between them. Since there is often a greater volume of data being transported in one direction than in the other (more frequently in a forward direction, for example from BSS 32 to MS 40) the number of channels opened in both directions does not need to be equal . For example, there may be four front channels and only open reverse channels. In each direction, there is preferably a fundamental code traffic channel, which carries the signaling (Figure 2A) together with the data, and up to seven supplementary code traffic channels for the high-speed data. The fundamental channel is substantially active continuously, while the supplementary channels are activated as necessary based on the total data rate or proportion at any time. The use of MDR for the transmission of high-speed, GSM-switched circuit data (HSCSD) is similarly described in the aforementioned U.S. patent application entitled "Transmission of Data Switched by GSM Circuit over a Link. of CDMA ". Figure 3 is a schematic block diagram illustrating a hybrid GSM / CDMA cellular communication system 21 according to a preferred alternative embodiment of the present invention. System 21 is similar to system 20 shown in Figure 1, except that in system 21, standard CDMA data communications, preferably based on IS-707, are offered as a specific GSM operator service, for example, a packet data transfer service that is not specifically defined or supported by the GSM network specification. In this case, the data in MS packets 40, preferably in the form of IP data, are transferred to PDN 48 directly by the GSM-CDMA BSCs 34, rather than through GPRS 50. (The system 21 may or not include a GPRS, independent of the data link in IP packet, direct, shown in Figure 3). PDN 48 preferably comprises the Internet or is connected to the Internet, although the architecture of the system 21 can similarly be used to link in MS 40 other types of data networks known in the art, such as LANs, WANs and "intranets". The data is preferably transported between the MS 40 and the BSSs 32 according to the CDMA IS-657 and IS-707 standards mentioned hereinabove. A router associated with PDN 48 routes the IP messages for MS 40 via any BSC 34 that is in communication with MS. Preferably, when MS 40 is changed from one BSC to another, the PDN is informed of the change and reroutes the IP messages to the new BSC based on the Mobile IP Standard. The Mobile IP standard is defined in the RFCs of the IETF, specifically they include the RFCs 2002, 2003, and 2004, which are incorporated by reference herein. A GSM service node known as a service control point (SCP) 58 communicates with the BSCs 34 and with the MSC 24 so that it is possible for the MSC to control MS 40 access to the system 21 and manage the network services such as billing, in connection with the transmission of data in packets through the BSCs. SCP 58 communicates MSC 24 via an interconnection of the GSM operator specific service (OSS). BSS 32 thus has several interconnections that are used to support data transfer between MS 40 and PDN 48: • the CDMA air interconnection between BTS 36 and MS 40; • the interconnection of IP to PDN 48; • the interconnection from A to MSC 24; and • an owner interconnection for SCP 58. Figure 4 is a schematic signaling diagram, illustrating the procedures involved in system elements 21, shown in Figure 3A, and the transfer of IP traffic between MS 40 and PDN. 48, according to a preferred embodiment of the present invention. When MS 40 has data to send, it initiates a GSM call to BSS 32, which consequently makes contact with MSC 24 to request the start of the call. MSC 24 authenticates to MS 40 and adjusts an encryption or encoding mode (if applicable), in accordance with GSM standards, and then consults SCP 58 in order to proceed with the call. The SCP then notifies BSS 32 that it is allowed to proceed with the call. At this point, the BSS allows the MS 40 to send and receive IP data packets to and from MS 40, in accordance with IS-657 and IS-707, and transfers the packets to PDN 48, and again from the PDN to MS . When MS 40 has finished sending and receiving the data, it notifies BSS 32, which consequently sends a request to SCP 58 and / or to MSC 24 to release the call. The BSS then transfers the billing information in relation to the call to the SCP 58, which passes the information to the MSC 24 or directly to a billing system associated with the PLMN 22. In a preferred, alternative embodiment of the present invention, the SCP 58 communicates with the MSC 24 via a GSM CAMEL interconnection (custom applications for the improved mobile network logics), instead of the OSS interconnection described hereinabove. CAMEL, although still in development, is intended to provide a standardized structure for such communications, rather than the owner OSS interconnection. CAMEL is defined in standards 02.78, 03.78 and 09.78, which are incorporated by reference herein. Figure 5 schematically illustrates a hybrid GSM / CDMA cellular communications system 23 according to another preferred embodiment of the present invention. In the system 23, the BSCs 34 are linked to the PDN 48 as shown in Figure 3, but SCP 58 is bound and transfers the service data to a home location register (HLR) 60 associated with the PLMN 22, instead from MSC 24. In this case, MS 40 transfers unstructured supplementary service data (USSD) to the HLR, as indicated by dashed lines in Figure 5, and the HLR communicates with the SCP via an interconnection of proper owner. Although preferred embodiments are described herein above with reference to a particular GSM / CDMA hybrid system, it will be appreciated that the principles of the present invention can be similarly applied to effect the transfer of data over air, in other hybrid communication systems as well. Similarly, although the systems and methods described hereinabove make specific reference to the transfer of data in IP packet, these can also be used for other modes and standards of data communications. The scope of the present invention encompasses not only the complete systems and communication processes described hereinabove, but also various innovative elements of these systems and processes, as well as the combinations and subcombinations thereof. It will be appreciated in this way that the preferred embodiments described above are cited by way of example, and the full scope of the invention is limited only by the claims.

Claims (34)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property: 1. A method for transferring data in packets between a mobile station and a GSM network, comprising: communication with a GSM mode of service to establish a data link between the mobile station and the network via a radio communication base station - the transfer of packet data between the mobile station and the base station over a CDMA air interconnection; and the transfer of data on the link between the base station and the network. A method according to claim 1, wherein the communication with the node comprises communication with a GPRS node, and wherein the transfer of the data comprises the transfer of the data via the GPRS node. 3. A method according to claim 2, wherein the communication with the new GPRS comprises communication with an SGSN via a Gb interconnection of GSM. 4. A method according to claim 2, wherein the data transfer comprises the mapping of the GPRS tables on the CDMA air interconnection. A method according to claim 4, wherein the mapping of the GPRS data frames comprises the use of a CDMA radio link control, to support a GPRS logical link control. 6. A method according to claim 1, wherein the transfer of the data comprises the transfer of the data as a specific service of GSM operator. A method according to claim 6, wherein communication with the node comprises communication with a GSM service control point, which communicates with a switching center via the GSM operator specific service interconnection. A method according to claim 7, wherein the mobile station communicates with a home location register via a GSM unstructured supplementary service data interconnection. 9. A method according to claim 7, wherein the service control point communicates with a switching center via the custom GSM applications for enhanced logical interconnection of the mobile network. A method according to claim 6, and comprising the change of mobile station from the base station to another base station, wherein the transfer of data over the link comprises routing the data to the other base station using mobile IP . A method according to claim 1, wherein communication with the service node comprises communication with a switching center via a GSM interconnection A. 12. A method according to claim 1, wherein the transfer of the data comprises the transfer of the data directly between the base station and the network, substantially without passing the data through the service node. A method according to claim 1, wherein the communication with the service node comprises the provision of GSM authentication of the mobile station for a call made on the CDMA air interconnect. A method according to claim 1, wherein the transfer of the data comprises the transfer of data over a CDMA air interconnection based substantially on an IS-95 interconnection standard. 15. A method according to claim 14, wherein the data transfer comprises transferring the data at a variable speed, which responds to a volume of data that is to be transferred over the air interconnection. 16. A method according to claim 15, wherein the transfer of the data comprises the opening of a fundamental channel for the transfer of the data and the signaling on it, and which responds to the volume of data that opens one or more supplementary channels between the station mobile and the base station to carry the data. 17. A method according to claim 16, wherein the opening of the supplementary channels comprises opening a different number of channels in the forward and reverse directions between the mobile station and the base station. 18. A method according to claim 16, and comprising the closing of one or more supplementary channels in response to a decrease in the data rate. 19. A method according to claim 1, wherein the data transfer comprises the transfer of the data using the packet data service of CDMA, IS-657 and IS-707. 20. A wireless communication apparatus, for use in a mobile communication system, comprising: a mobile station, which is coupled to exchange data with the terminal equipment, and which initiates a call to transfer the data over an interconnection of CDMA air; and a base station, which communicates with a service node of the GSM network to establish a data link responsive to the call initiated by the mobile station, and which transfers the data between the mobile station and the network over the data link The apparatus according to claim 20, wherein the service node comprises a GPRS node, and wherein the base station transfers the data via the GPRS node using a GPRS communication protocol. 22. The apparatus according to claim 21, wherein the GPRS node comprises an SGSN, with which the base station is communicated via a GSM Gb interconnection. 23. The apparatus according to claim 20, wherein the data is transferred over the data link as a GSM-specific operator service. 24. The apparatus according to claim 23, wherein the node of the GSM network comprises a GSM service control point, which communicates with a switching center via an operator specific service interconnection. 25. The apparatus according to claim 23, wherein the mobile station communicates with a home location register via an unstructured GSM supplementary service data interconnect. 26. The apparatus according to claim 23, wherein the service control point communicates with a switching center via one of the custom GSM applications for the improved logical interconnection of the mobile network. 27. The apparatus according to claim 20, wherein the data link comprises a direct connection between the base station and the network. The apparatus according to claim 27, wherein the data is transferred over the direct connection, substantially without passing through the service node. 29. The apparatus according to claim 20, wherein the air interconnection is substantially based on an air interconnection standard of CDMA, IS-95. 30. The apparatus according to claim 29, wherein the data is transferred over the air interconnection at a variable speed, which responds to a volume of the data. The apparatus according to claim 30, wherein the air interconnection comprises a fundamental channel for transferring and signaling the data thereon, and one or more supplementary channels that are opened in response to the volume of data to carry the data. 32. The apparatus according to claim 31, in one or more supplementary channels comprise a different number of channels in the forward and reverse directions between the mobile station and the base station. The apparatus according to claim 31, and wherein one or more supplementary channels are closed in response to a decrease in the data rate. 34. The apparatus according to claim 29, wherein the air interconnection operates substantially in accordance with the CDMA, IS-657 and IS-707 packet data service.