Iterative Distortion Cancellation Algorithms for Single-Sideband Systems

We propose an iterative distortion cancellation algorithm to digitally mitigate the impact of double-sideband dither signal amplitude from the automatic bias control module on Kramers-Kronig receivers without modifying physical layer structures. The algorithm utilizes the KK relation for initial signal decisions and reconstructs the distortion caused by dither signals. Experimental tests in back-to-back showed it improved tolerance to dither amplitudes up to 10% Vπ. For 80-km fiber transmission, the algorithm increased the receiver sensitivity by more than 1 dB, confirming the effectiveness of the proposed distortion cancellation method.