Performance of ADC resolution-limited optical coherent receivers with DA-ML carrier phase estimation

Abstract

We investigate the performance of decision-aided maximum likelihood (DA-ML) carrier phase estimation (CPE) algorithm in analog-to-digital converter (ADC) resolution-limited optical coherent receivers. The signal model of ADC resolution-limited receiver is established, and its bit error rate with DA-ML CPE in M-ary phase-shift keying (MPSK) system is analyzed. Simulation results show that $$N+2$$N+2 (N bits per symbol)-bit resolution is acceptable and $$N+3$$N+3 bit is sufficient for DA-ML receiver in MPSK $$(M=4, 8, 16)$$(M=4,8,16) system, and for 16-ary quadrature amplitude modulation system, 6-bit resolution is reasonable. Simulation and theoretical analyses both indicate that the optimal ADC quantization range equals to the average amplitude of received symbols which carry the information symbols with the highest energy on the constellation.