LAUSR

A simple equation for the estimation of in-band crosstalk-induced power penalty has been derived by considering the symbol peak power as well as the impact of the average intersymbol distance in various modulation formats of optical signals. The derived equation can easily estimate the in-band crosstalk-induced penalty by considering the level of crosstalk and Q-value. Among various formats of signals, the in-band crosstalk-induced penalties in on-off keying (OOK), differential quadrature phase shift keying, and pulse amplitude modulation-4 (PAM-4) signals have been estimated for comparison. From the results, we reconfirmed that the OOK non-return-to-zero signal would be 9 dB more tolerant to in-band crosstalk than the PAM-4 signal. The estimated results agreed well with the measured results.