Effects of carrier phase estimation on front-end IQ mismatch compensation in mode division multiplexed MIMO coherent receiver

The effects of carrier phase estimation on IQ mismatch compensation are investigated and compared for coherent MIMO optical receiver. We investigate the impacts of phase IQ mismatch on required optical signal-to-noise ratio (OSNR) for coherent MIMO detection. The impacts of number of modes and analog-to-digital converter (ADC) resolution are also evaluated. The results show that decision-directed carrier phase estimator could compensate significant amount of IQ mismatch without employing additional compensation technique, and relaxes requirement of ADC resolution.