Modifications to Finite Difference Algorithm for Polynomial Phase Signal Parameter Estimation

The finite difference (FD) algorithm is a recently proposed algorithm for single-component polynomial phase signal (PPS) parameter estimation. It can handle high-order PPSs, while being computationally simple. A drawback of the algorithm is that it cannot operate at lower signal-to-noise ratios (SNRs). We propose modifications to allow the FD algorithm to operate at lower SNRs. The modifications are magnitude weighting for phase values, phase difference filtering, and iterating the polynomial refinement step. Simulation shows that these modifications can reduce the algorithm's SNR threshold by 5 dB, without greatly increasing the computational complexity.