OPTICAL DQPSK VIDEO SYSTEM WITH HETERODYNE-DETECTION

Ten 50 Mb/s video channels are transmitted with a quadrature phase shift keying format on five microwave subcarriers. Using a differential encoding technique, no carrier recovery circuit or phase-locked loop is required for demodulation. It is demonstrated that only simply delay and multiply demodulator is necessary. In addition to simplicity, DQPSK modulation also provides very good receiver sensitivity and bandwidth efficiency. With heterodyne detection, a receiver sensitivity of - 41 dBm is achieved.