A novel nonuniform sampling method and processing system to overcome the Nyquist limit and suppress the noise

摘要

A method for nonuniform sampling based on amplitude of signals is proposed. It combines sampling rate with amplitude of signals. It make the most of some special samples that it helps to process signal so it is very effective to suppress noise. A sampled threshold should be computed and selected automatically in this algorithm. The mean and maximum amplitudes of signal decide the sampled threshold. It can estimate exactly the frequency of signal hidden beneath the noise when signal-to-noise ratio (SNR) is below -15 dB. The system can detect the signal above 18 MHz at the maximal sampling of 1.5 MHz, achieving 24 times the bandwidth of a classic uniformly digital signal processing (DSP) system that only can detect the signal above 0.75 MHz at the sampling of 1.5 MHz.