Abstract:

To enhance the phase measurement accuracy with a fixed amount of samples, a double subsegment measuring phase method is proposed, which is derived from all phase fast Fourier transform(FFT). In the proposed method, only the first subsegment and the last subsegment among the N subsegments included in all phase FFT are taken out, and accurate phase measurement can be finished through synthesizing the phase information of the peak spectra from these two segments FFT spectrums. Theoretic analysis is also conducted to analyze the reason why the proposed method has higher phase measurement accuracy than that of all phase FFT in noisy circumstance. Moreover, simulation also shows that, when the signal-to-noise rate is not too low, the phase estimation variance of the proposed method is between that of all phase FFT and Cramer Rao lower bound CRLB of two parameters, which endows the proposed method with wide application prospects.