Narrowband FM cellular system

Abstract

This paper describes the voice and data transmission parameters of a spectrallyefficient analog FDMA cellular system having 12.5 kHz channel assignments.Low-speed 100 bps Manchester data is transmitted during voice activity and provides channel control. In addition, 200 bps baseband data patterns support channel supervision. The use of this sub-audible 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 faking protection over current systems.