ORTHOGONAL MULTIPLEX SIGNAL PROCESSOR

PURPOSE:To keep the compatibility with an existing NTSC receiver and to extend the service area. CONSTITUTION:A transmitter side correlation discrimination device 41 outputs a selector control signal alpha based on line correlation of a video signal. A correlation encoder 55 controls the polarity of a digital audio data signal for each lien based on the selector control signal alpha. An orthogonal modulation device 3 applies orthogonal modulation to the video signal and a digital audio data signal from the correlation encoder 55 and the result is transmitted. A receiver side correlation discrimination device 61 obtains a selector control signal alpha' based on the line correlation of the demodulation video signal. A correlation decoder 62 controls the polarity of a demodulated digital audio signal for each line based on the selector control signal alpha' and adds/subtracts them to suppress a leaked component of the video signal and the digital audio data are reproduced.