Low complexity non-decision-aided carrier frequency offset estimator

In burst mode communication, a precise frequency correction is required. For digital modulated QAM signals with a relationally symmetric constellation, a feedforward low complexity carrier frequency offset estimator, operating in non-decision-aided mode, is proposed. Two new phase unwrapping methods are proposed to extend the estimation range of the estimator. At moderate to high signal-to-noise ratios the estimation range is extended to ±1/(2MT) for 2 π/M rotation symmetric constellation. The implementation complexity of the new estimator increases linearly with the observation length. The performance is assessed by computer simulation for 4QAM signals