Title :
Narrowband FM cellular system
Author :
Levine, Steve ; Carney, Scott ; Baker, James
Author_Institution :
Motorola Inc., Schaumburg, IL, USA
Abstract :
The voice and data transmission parameters of a spectrally-efficient analog frequency division multiple access (FDMA) cellular system with 12.5 kHz channel assignments are described. Low-speed 100 bit/s Manchester data is transmitted during voice activity and provides channel control. In addition, 200 bit/s baseband data patterns support channel supervision. The use of this subaudible signaling method has yielded improved system operation. Eliminating the high-frequency supervisory audio tone has reduced adjacent-channel interference and has allowed increased voice deviation. Using the low-speed data for control messages does not require interruption of the voice activity. The handoff and disconnect protocols have improved falsing protection over current systems
Keywords :
cellular radio; data communication systems; frequency division multiple access; frequency modulation; radiotelephony; voice communication; 100 bit/s; 12.5 kHz; 200 bit/s; FDMA; FM cellular system; Manchester data; adjacent-channel interference; analog system; baseband data patterns; channel assignments; channel control; channel supervision; data transmission; disconnect protocols; falsing protection; frequency division multiple access; handoff protocol; narrowband system; subaudible signaling method; transmission parameters; voice transmission; Baseband; Channel spacing; Data communication; Frequency division multiaccess; Interference elimination; Narrowband; Protection; Protocols; Research and development; Speech;
Conference_Titel :
Vehicular Technology Conference, 1990 IEEE 40th
Conference_Location :
Orlando, FL
DOI :
10.1109/VETEC.1990.110327
