The intention of this report is to give a picture of existing digital radio systems as well as of future systems under development. The emphasis is put on systems based on European standards and on research done in Europe. The following systems are introduced: · GSM, a second generation public mobile system offering speech, data and supplementary services with basically global coverage. · DCS1800, a variant of the GSM standards offering more capacity in urban areas by using a higher frequency band. · TETRA, a private mobile radio system providing high reliability and short set-up times needed by emergency applications. · DECT, an air interface specification for applications such as cordless telephones and RLANs (Radio Local Area Networks). ...