 introduction of a PCN. IEE Coloquium GSM and PCN En- Proc. IEEE, April. hanced Mobile Services, IEE Digest no. 1991/023. Gaskell, P.S. (1991) Elaboration of the DGS1800 standard for PCN Martin, P.C. Networks and Telecommunications Design and Oper- service. IEE Colloquium GSM and PCN Enhanced Mobile ation, John Wiley and Sons. Services, IEE Digest no. 1991/023. HMSO (1989) Phones on The Move, UK Department of Industry. Mischa, S. (1988) Telecommunications Networks Protocols, Mod- elling and Analysis, Addison-Wesley Publishing Co. Jakes, W.C.Jr. (Ed.) Microwave Mobile Communications, Wiley-In- terscience. Vincent, G. (1990) Personal communication: the dream and the Knight, P. (1991) Network planning using GSM and GSM based reality, IEE Review, 36, (8), September. standards. IEE Colloquium GSM and PCN Enhanced Mobile William, C.Y.L. (1986) Mobile Communications Design Fun- Services, IEE Digest no. 1991/023. damentals, Sams. Cordless telecommunications R S Swain C Eng MIEE BT Laboratories Contents Introduction 49/3 Digital technology 49/3 49.3 CT2/CAI digital specification 49/4 DECT digital specification 49/8 References 49/13 This page intentionally left blank Introduction 49/3 49.1 Introduction (21MHz and 46MHz). More recently the North American market has concentrated both directions of transmission in the region of Cordless telephone products first appeared as a low cost option for 49MHz in order to give more transmission channels and hence more the home in North America during the late 1970's. Technically it transmission capacity. The technology, however, is basically the was a radio extension telephone that operated at low power, to same and retains the very attractive low production cost. conserve operating time between battery charges, and frequencies of 1.7MHz (base to handset) and 49MHz (handset to base). The 49.1.3 European 900MHz analogue standard chosen technology was analogue frequency modulation which re- sulted in prices around $100 for a residential unit. Although range Another body of opinion in Eur