Internetworking central for mobile radio network

p0001The invention relates to an interworking central to the preamble of claim 1 and a so-equipped mobile network.

p0002From the by M. Mouly and M.-B. Pautet, self-published, 49 rue Louise Bruneau, 91120 Palaiseau, France, 1992 published book "The GSM", pages 102 and pages 149-154 are adapting means for the GSM mobile network (GSM) known. The adjustment means described therein result from so-called "Interworking Functions" to adapt the data signals to the protocols and data rates used in these networks for data transfers between the mobile network and a telecommunications network. Accordingly, the "Interworking Functions" exporting adaptation funds are used for mutual adjustment of various data transmissions. In the book "The GSM" third paragraph on page 149, describes that these "Interworking Functions" z. B. can be implemented in each mobile station. Further is described there that the "inter-working functions" can be implemented in a network adaptation center that is connected to multiple mobile switching centers. Like these there called "Centralised approach" structure of the mobile network should be set up, is not described therein.

p0003Furthermore, from the article "data transmission in digital mobile networks" of R. Hinz, appeared on pages 37-40 in the journal "telekom praxis", Volume 72, August 1995 Fachverlag Schiele and Schön, Berlin, also have to be "Interworking Functions" known designated matching agent. There indeed different adaptation agents are described, integrating these into a power adjustment headquarters there but not described.

p0004Object of the invention is to provide an interworking Office for a simple construction of a mobile network with the above structure.

p0005The object is achieved by a power adjustment unit with the features of claim 1 and by a so-equipped mobile phone network after the independent claim.

p0006Accordingly, the net adjustment panel is connected to multiple mobile switching centers of the cellular network, establish the communication links between the mobile network and a telecommunications network. The interworking Center contains various adjustment means for adjusting the mobile radio network to different data transmitting node of the telecommunication network and a switching network and at least one associated control, by means of which each of the adjustment means is connectable to each of the mobile switching centers in order to switch optional single one of the adaptation means in individual ones of the data transmission connections.

p0007Thus, the interworking Center contains various adaptation means to adapt data transfers between multiple mobile switching centers of a mobile network and various data transmission node of a telecommunications network and a controlled switching matrix that connects the various adaptation funds optionally with the mobile switching centers.

p0008Characterized a means is provided centrally in the mobile network, wherein each of the mobile switching centers has access to each of the different adaptation means. It must therefore not be all adaptation means multiple, ie separately installed in each mobile switching center. In the interworking Central only as many adaptation means need be provided, as is required with an average utilization of the available data services. The interworking headquarters invention is very inexpensive and easy to set up, for example by making recourse to the assembly of a switching device, already include a switching matrix.

p0009Further embodiments of the invention are disclosed in the dependent claims.

p0010In the following the invention will be described using an exemplary embodiment and with the aid of two figures, of which:<dl id="dl0001"><dt>Fig. 1</dt><dd>schematically shows the structure of a mobile radio network to a central data transmission device and</dd><dt>FIG. 2</dt><dd>the block diagram of the central data transmission device displays.</dd></dl>

p00111 shows schematically the structure of a mobile radio network with a MRS interworking central CIWF and a plurality of associated mobile switching centers MSC, restore the data transmission connections DATA to a telecommunication network TN. The mobile network also includes more connected to the mobile switching centers MSC base station subsystems BSS. The base station subsystems include base station controllers, not shown with connected base stations. Each base station subsystem BSS provides a portion of the mobile radio network MRS, a so-called radio cell cluster. Mobile stations MS moving in the cellular network are wirelessly connected to the base stations of the base station subsystems BSS.

p0012In order to perform data transmission between such a mobile station MS and a subscriber device of the telecommunication network TN, a data transmission connection referred to in the following also shortly compound DATA, made by the mobile station MS via the mobile switching center MSC to a data transmitting node of the telecommunications network. Among data transmitting node is understood here also equipped with a modem subscriber. In Fig. 1, four different data transmission node, a second PAD are exemplified, of which a first MOD represents a modem for a personal computer, a so-called "packet assembler / disassembler" represents V.24 standard, a third PH a so-called "packet handler "is to X.25 standard and a fourth ISDN represents a data transmission node to access the ISDN network. Will send a message EMAIL means of data transmission service "electronic letter (e-mail)" to a subscriber of the telecommunications network TN via his mobile station MS, for example, a mobile subscriber, so here is a data transmission connection is established to the modem MOD and the associated personal computer of the participant. In the example of FIG. 1, the mobile network is a program executed by the GSM standard cellular mobile radio network. Accordingly, the predetermined in the mobile network transmitting data according to a GSM protocol, called the Radio Link Protocol, carried out and adjusted by the adaptation means to a data transfer that is specified by the CCITT standard V.42. These different protocols are used for error correction and data backup and are in Fig. 1, with GSM and V.42. The adjustment of the data transmission and the connection establishment and release is described below with reference to FIG. 2.

p0013In FIG. 2, the interworking central CIWF is shown schematically. This contains various adaptation funds IMF1 to IWFn. In this example, it is for each of the four data transmitting node, an adaptation means are provided. However, only the following two adapter means are here shown in simplified form: a first adaptation means IWF1 for a connection with the modem MOD, and a second adaptation means IWFn for a connection to the data transmitting node ISDN. The interworking Central CIWF further includes an associated with the adaptation means switching network SWT and related controls CC that the switching network SWT control so that random connections between the mobile switching centers and the adaptation means can be produced. This establishes a connection between each mobile switching center and each data transmitting node is possible, whereby the data transmission between the mobile network and the telecommunications network is adapted by the adaptation means corresponding to the requirements of the data transmission node. In the basic operation of the various adaptation funds will not be described here, but refer to the aforementioned article by R. Hinz.

p0014To carry out the aforementioned data service "E-MAIL", the data transmission from the mobile station via the corresponding base station subsystem BSS and the associated mobile switching center MSC is guided to the interworking central CIWF. The signaling information IAM, which sends these mobile switching center MSC in accordance with the protocol GSM to the interworking Central CIWF is evaluated within one of the controllers CC, which controls the switching matrix, that the data transfer is performed on the adaptation means IMF1. This adaptation means adapts the molded according to the protocol GSM data signals to the required for the modem MOD protocol V42.

p0015Each of the adapter means IWF1 to IWFn consists of a processor-controlled circuit, each one of the aforementioned "Interworking Functions" executes. In this example, the first adaptation means evaluates IMF1 coming from the mobile network data signals, converts the modulation rate of 9600 bits / s to 14400 bit / s and modulates the data signals coming from the mobile network. The messages from the telecommunication network TN data signals are demodulated in reverse order, and adapted to the smaller step speed. Accordingly, the adaptation means is bidirectional and includes a modem function to convert the transmitted in the mobile network digital data signals into analog Akkustiksignale for transmission in the telecommunications network.

p0016By the switching network SWT and the associated controllers CC described above optional connections can be switched so that each mobile switching center MSC and therefore each mobile station has MS of the mobile network access to each adaptation agent IMF1 to IWFn. Since on average over time, only a limited number of participants (about 10%) take the same time a data transmission service or assistance, only a limited number must be provided to adaptation funds available within the central data transmission device CIWF. Thus, a low-cost design of the mobile network is possible. Further, be used in the construction of the interworking Center on assemblies which have been developed for a conventional switching center, such as the "System 12" of Alcatel and which already contain a switching matrix and the necessary controls.

p0017Both multiple controllers for distributed control of the switching matrix and a single controller for centralized control are used.

p0018A data transmission connection can not only, as described above, first looped back to the mobile switching centers, before being passed to the telecommunications network. It is also possible to perform the data transmission from the mobile stations to the interworking unit and from there directly to the telecommunications network. Further integration of interworking headquarters in one of the mobile switching centers is conceivable.

p0019The example described above is only one embodiment of the invention in which a mobile radio network is adapted to a telecommunications network. The adaptation means described serve the adjustment of a GSM data transfer a landline data transmission within the data transmission service "e-mail". However, numerous other examples conceivable, such as adaptation to data transmitting nodes for fax services, dual voice and data services or so-called HSCD data services (HSCD: High Switched Data). Furthermore, applications of the invention are also conceivable in which different mobile networks, especially cellular mobile communication networks of different standards are matched.