Subcarrier-Multiplexed Coherent Optical Video Transmission Using Direct FrequencyModulation of Semiconductor Lasers

摘要

An analog subcarrier-multiplexing (SCM) coherent optical system for videotransmission using direct frequency modulation of semiconductor lasers is analyzed. Receiver sensitivity, corresponding to a 56 dB SNR at the output video ports, is approximately -38 dBm for 50 channels and -25 dBm for 100 channels using the FM subcarrier modulation format. These results are obtained for realistic values of receiver thermal noise (3.31 x 10 (-22)A(2)/Hz), laser linewidth (40 MHz), RIN (-150 dB/Hz), and optical bandwidth (20 GHz). Linewidth-induced performance degradation is found to be negligible for up to 50 channels.