Performance analysis of optical heterodyne FSK systems with nonuniform laser FM response

A simple analytical model for evaluating the system performance due to the combined effects of receiver noise, laser phase noise, and laser non-uniform FM response in wide-deviation heterodyne optical FSK system with envelope detection is presented. With this approach, the relative effectiveness of several linecoding schemes, such as alternate mark inversion (AMI), Manchester coding (MC), and delay modulation (DM), in counteracting the pattern dependent performance degradation due to non-flat FM response has been quantitatively assessed. Theoretical and simulation results show that the performance of linecoded systems are within 0.7 dB at bit error probability of 10/sup -9/ from the random non-return to zero (NRZ) FSK system with flat FM response.<
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