Differential FM Transmission Scheme for Picture Signals Multiplexed by TAT Bandwidth Compression

Abstract

This paper proposes an efficient new FM transmission scheme for picture signals. The proposed scheme transmits two TV signals over a single channel for the conventional FM transmission of one TV signal. This scheme employs two new techniques : multiplex of picture signals by using TAT (Time-Axis Transform) bandwidth compression and FM transmission of a differential signal. The SN ratio of the reconstructed picture signal and the bit error rate of the control information are analyzed in the proposed scheme. An improvement in the SN ratio of about 6dB is achieved by making a difference in the picture signal and companding its amplitude. The results of the analysis are applied to multiplex transmission systems for international satellite communication and satellite broadcast. These systems are expected to transmit two TV signals over one transmission channel with an SN ratio of more than 40dB.