Fast Frequency Estimation Methods of Real Sinusoidal Signal from Phase Differences

Based on the principle of minimum mean square error frequency estimation from phase differences,the new modified frequency estimation methods from phase differences directly for real sinusoidal signal are presented in this paper.The new methods can rapidly and efficiently obtain the informations of a real sinusoidal signal's phase on time domain or frequency domain by zero-crossings or FFT transforming.The modified methods can extend the threshold SNR of frequency estimation,and it is easily implemented.