关键词: 欠采样, 多正弦波信号, Nyquist采样, 低信噪比

Abstract: To solve the problem of low computation speed and high cost caused by A/D converter and latter processors in high-frequency section, a novel method for multiple frequencies estimation of high-frequency sinusoidal signals based on sub-Nyquist is proposed. Signals are divided into two channels, which are sampled in sub-Nyquist frequency respectively. A new signal is constructed through the two channel signals to obtain a dummy Nyquist value. Fourier transformation is used to obtain the frequency estimation. The frequency can be obtained directly when there is only one signal. Under the circumstance of multiple signals, the two channels FT results are applied to eliminating the false frequency caused by frequency crossing. Simulation results verify the effectiveness of the proposed algorithm.

Key words: sub-Nyquist sampling, multiple sinusoidal signal, Nyquist sampling, low signal noise ratio