A Phase Offset Blind Estimation Algorithm for QAM Modulation and Its FPGA Implementation

This letter presents the design, implementation, and validation of an FPGA-based phase offset estimation and compensation algorithm for RF communication systems. The algorithm improves the vector-valued phase estimator (VVPE) method by selecting the outermost constellation points to improve the phase estimation accuracy, and it supports various QAM modulation schemes. The effectiveness of the algorithm is first verified through MATLAB simulations and Pluto SDR-based experiments, during which the optimal value of the averaging filter parameter N is determined. The algorithm is then implemented on an FPGA, and a test system is developed in conjunction with RF instruments to validate its performance. The experimental results demonstrate that the proposed system achieves high accuracy, low latency, and efficient utilization of hardware resources, making it suitable for practical communication applications.