Introduction of data services into mobile telephone systems

A general and important effort has been undertaken in recent years to develop both data networks and mobile telephone systems. These two areas have grown, however, independently without much attention to their mutual coherence. Thus, to overcome this situation, recent research has been preparing the introduction of data services into the mobile aera. Several approaches in this research are the following: 1. The creation of dedicated networks 2. The creation of mixed networks 3. The introduction of data communication in existing mobile-telephone networks. Most of the papers on this subject deal with the first two approaches. But in fact it is the last approach that is identical to what has been the introduction of data communication into telephone switched networks during the last ten years, and it is this last approach that is presented in this paper. The problems of compatibility between the CCITT recommendations for modems and data networks on one hand and the criteria with which mobile radio networks have to comply on the other hand are the heart of the discussion.