Effects of low cut-off frequency of optical receiver on the performance of lightwave systems using pilot tones

We investigate the effects of low cut-off frequency of optical receiver on the performance of lightwave systems. The results show that we can reduce the tone-induced power penalty by ∼0.8 dB (tone frequency = 1 MHz) using a high-pass filter in the optical receiver. In addition, our calculation shows that the power penalty can be negligible (<0.1 dB) even when the low cut-off frequency of the 10 Gb/s optical receiver is increased up to ∼10 MHz.