The effects of phase noise on the coherent detection of optical on-off keying

An analytical treatment of the detection bit error rate (BER) for on-off keyed (OOK) coherent lightwave signals corrupted by phase noise is presented. In the reception scheme considered, the lightwave signal is heterodyne-detected to produce an electrical bandpass signal, which is then noncoherently detected to produce the baseband pulse stream. Square-law envelope detection followed by low-pass filtering is assumed. This enables the computation of the BER as a function of IF signal-to-noise ratio (SNR) for different degrees of phase noise severity. In the process, critical parameters such as decision threshold and IF filter bandwidth are optimized. It is shown that if these receiver parameters are suitably chosen, very large amounts of phase noise can be tolerated with little increase in required SNR.<>