Cordless-cellular network integration for the 3rd generation personal communication systems

The trend towards the third generation PCS (personal communications systems) calls for support of multimedia services in a multi-layered cell architecture system via multi-air interfaces with multi-operators and multi-services provider, offering a reliable and contiguous world-wide coverage in order to allow seamless roaming for subscribers. The coverage ranges from low speed, high user density environments such as the business sector to high speed, low user density open areas. It is realised that all users and operators' requirements can not be economically met by one system but through a combination and enhancements of existing fixed, cordless, cellular, satellite and data networks, which are designed around a specific set of services and environments. Clearly, there is a need for such systems to interwork together in a co-ordinated manner to satisfy three main requirements of the third generation PCS, i.e. coverage, mobility and service. Interworking between cordless, and cellular systems, e.g. DECT and GSM, is thoroughly investigated. The mobility related issues in the context of registration, location management and call routing are discussed. Then the signalling load issue in the interworking system is investigated and some new techniques are proposed to reduce the imposed signalling load on the cellular system's network.