Robust IQ Imbalance Compensation for Free Space Optics Communications Links

In this paper, we propose a robust IQ compensation scheme for optical communication links, which consists of two compensation stages. Through targeted simulations and experimental measurements, we demonstrate that the proposed approach achieves an improvement of over 1 dB in signal-to-noise ratio (SNR) compared to typical single-stage processing. This double-stage IQ imbalance compensation effectively addresses phase and amplitude imbalance effects that degrade the performance of coherent optical communication systems. By mitigating the imbalances introduced by the receiver front-end and the transmitter modulator, our scheme enhances overall system performance. The improvement in SNR underscores the robustness and reliability of our approach, making it well-suited for high-demand optical communication networks.