PERFORMANCE OPTIMIZATION OF DIRECTLY MODULATED FM-SCM SYSTEMS WITH OPTICAL DISCRIMINATOR

New theoretical models were developed that accurately describe the beh avior of directly modulated communication systems with a predetection optical frequency discriminator. A 10-channel 100 Mbit/s subcarrier mu ltiplexed system with a DFB laser light source and fiber Fabry-Perot d iscriminator was built. For an input optical power of - 17 dBm the sys tem with the 67 GHz Fabry-Perot filter achieved an optimal CNR of 23 d B at the frequency modulation index (beta) of 0.5, compared to optimal CNR of 17 dB at beta almost-equal-to 0.3 for the system with the 10 G Hz discriminator. System performance demonstrated excellent agreement with the theoretical predictions.