Quality presentation method especially for GSM radio network

The present invention relates to a method for Integration of cordless telephone networks, in particular the DECT standard, especially in GSM cellular networks Mobile networks.

Known mobile telephone networks, for. Example, the GSM standard, are to Supply of fixed in vehicles or equipment compact, mobile handsets are provided. are also known Schurlostelefone according to the DECT standard, the fixed networks operate. As mobile switching centers after GSM standard are called Mobile Service Switching Centres MSC, the normal next functionalities Exchanges in addition the mobility of terminals support. In this case, a special mobility Management, MM applied.

There are already cases discussed z. T. also specified in which is a DECT system network side with a GSM system, ie over the A-interface (interface between Switching center and base station) or an ISDN Compound with each other. A network-based compound to achieve between a GSM network and a DECT network but requires expensive Specification and Development work and can not be realized in a short time. If there were an opportunity, at the power connection on already resorting existing components, so would be a short given the time of realization.

In the published patent application DE 43 44 702 A1 is a method and an arrangement for alternately operating a mobile Terminal via a cellular mobile radio system and a described cordless system of a fixed network. Here is it is primarily a call forwarding in case that a call attempt by an entrant over the wireless network fails. It is an alternative call number is provided on which call forwarding is to be switched when the not a participant under his home phone number can be achieved.

Disadvantage of the method described is that having the Diversion localization related, time-consuming of Mobile subscriber. Only in the case of non-availability the subscriber takes place a call forwarding to a predetermined DECT network.

The object of the invention is a method for integration cordless telephone networks into cellular mobile networks propose, which allows the subscriber whenever to supply directly via the network favorable to him.

This object is achieved by the technical teaching of Claim. 1

Substituting an almost universal coverage through a GSM network ahead, so it is possible according to the GSM internal mobility management function the DECT network over the GSM air interface to make it accessible.

The basic idea of ​​the invention is that a subscriber who over a two terminal systems has always the currently cheaper network is within range and called them directly is by starting from first GSM operation, the terminal constantly checks whether the participants in a by DECT network medically underserved area resident. If this is the case, will continue to be examined by the terminal if the subscriber is authorized to have access to the relevant DECT network. Is also this condition is fulfilled, the terminal initiates a Location update procedure (Location Update procedure) so that the GSM network to the present location (Location Area) can determine the subscriber.

After the location update is carried out successfully, , the terminal in the corresponding DECT mode pass. now When a call for the subscriber, then the current location of the subscriber with previously stored Location data compared to which corresponding numbers individual DECT networks are associated. The switching center (MSC) of the GSM network "knows" now that the subscriber under the respective DECT network is within range and conducts a Connection with the aid of the GSM mobility Management directly to the number of the respective DECT Network a. Outgoing calls from the participants are directly handled via the DECT network. According to the invention can be private DECT systems useful with GSM mobile radio systems combine. Communication via a DECT network offers the Participants significant advantages:

<ul><li>- High voice quality through cordless landline connection</li><li>- High traffic density in a small space, without interference</li><li>- Lower call costs for the subscriber because Landline tariffs.</li></ul>

Another advantage is the full integration of any DECT Networks in the GSM network with only minor modifications to the Networks and terminals. The terminal technology is already provided, the network-side standardization is up to some areas completed.

The supplied by DECT networks areas are called "islands" viewed in the GSM network. The islands have GSM Supply, but also offer the opportunity to cost-effective and higher quality DECT technology to use. Access to these DECT networks owning participants (depending by subscriber profile, multiple islands at different Locations possible), this participant the DECT network use. Wanted a participant previously use both networks, he needed two terminals, a GSM-compatible and a DECT compliant device. As a result of the possible variety of the islands is not possible, an ordinary to implement call forwarding to an unknown location, is it inventively provided that the GSM network in a shape Entry in the home location register (HLR) via the instantaneous Location of the subscriber is informed.

Similar to the GSM network so must the terminal as soon as a Location Change notes this change the HLR of the GSM Network notified so that the network is known, in which Location Area (Location Area) the subscriber is located. Knowledge of the HER on the whereabouts must be a the location area assigned number be assigned to a person calls to address them accordingly. In order to use the existing GSM Infrastructure without modification thereof, that the DECT Networks an their own location area (Location Area) can be assigned. This Location Area in With an existing customer is then a corresponding Number within the Community.

Regarding the location update procedure and the Notification of the HLR about the whereabouts of OPERATOR different scenarios are possible:

<ul><li>a) Actual components known from GSM Location Update Procedure.</li><li>b) setting on or off call forwarding (call forwarding unconditional).</li><li>c) short message to a newly einzurichtendes, intelligent Network element, the order notified the new phone number becomes.</li><li>d) call to a new einzurichtendes, intelligent network element, the then notified via DTMF tones the new phone number becomes.</li><li>e) modification of the GSM specification to specifically the DECT GSM roaming support functionality.</li></ul>

Further features of the invention emerge from the dependent claims forth.

So is continually monitored by the terminal, whether it is in an area covered by a cordless telephone network area is. This is a prerequisite for Cordless telephone operation. If the terminal is in a is by a cordless telephone network medically underserved area and the subscriber is authorized in the relevant grid, is by the terminal in the mobile network, a location update (Location Update Procedure) initiated to the whereabouts the subscriber to determine. The current whereabouts of the Subscriber as an entry in the home location register (HLR with GSM) the mobile radio network and continuously updated. After successful location update is the terminal optional or automatically by the mobile operation in the Cordless phone operation via.

The admissibility of the participant in the cordless telephone network can by attempt to connect or corresponding System IDs are checked, as well as in Mobile communications are applied. Each of the participants permissible cordless telephone network is an individual phone number associated with which is known to the mobile radio network, and under the the participants in the respective cordless telephone network is achievable.

About the cordless telephone network incoming calls are directly routed to the mobile device, as long as the participants in Supply range of the cordless telephone network is.

The connection between the mobile network and Cordless telephone network with GSM networks by means of Mobility Mangagement module, wherein the number of possible, integratable cordless telephone networks is arbitrary.