针对低信噪比条件下短时正弦信号的高精度频率估计问题,提出一种同频等长信号加权融合算法。首先,建立同频等长信号频谱模型,构造具有相位连续化特性和噪声对消特性的相位补偿矩阵;然后,利用相位补偿矩阵对同频等长信号频谱进行加权融合,使之基本达到与其总长度相等的相位连续信号频谱的分析效果;最后,谱峰搜索加权融合后的频谱,获得高精度的频率估计值。算法分析与仿真实验表明,与现有方法相比,本算法精度较高,计算量较小,抗噪性较强,普适性好,适用于任意类型的同频等长信号。
For high precise frequency estimation of the short sinusoid signal at low signal-to-noise ratio(SNR),a weighted fusion algorithm for frequency estimation of the short signal with the same frequency and length(SFL-Signal) is proposed.The spectrum model of SFL-Signal and the phase compensation matrix with phase coherent and noise cancellation are constructed.Secondly,the SFL-signal spectrum is weight-fused with the phase compensation matrix to obtain the result almost the same as that of the spectrum of the phase-coherent sinusoid signal.Consequently,high frequency estimation precision is obtained with spectral peak searching of the weight-fusion spectrum.Algorithm analysis and simulation results show that,compared with the existing methods,the proposed algorithm works better in term of precision,calculation complexity,noise immunity,and fits for any type of SFL-Signal.