基于DSP的周期信号等效采样系统设计与实现

针对现有的常规的等效时间采样系统必须具备准确的模拟触发电路，必须具备精确的定时电路或时长检测电路，并且波形重建时间长甚至不能完全重建的问题，提出一种基于DSP的新型周期信号等效采样系统设计。该系统采用三个两两互质频率进行三轮采样，从三轮采样数据估计出被测周期信号的基频和其它参数，从而重构出被测周期信号波形。实验证明，该采样系统在最大实时采样率为200MSps时的等效采样率可以达到10GSps。

Design and Implementation of the DSP Based on Equivalent Time Sampling System

A new equivalent time sampling system based on DSP is invented to solve the problem of normal equivalent time sampling system, which needs accurate trigger circuit, precision timing circuit or time measuring circuit. Sometimes the normal equivalent time sampling system even cannot wholly reconstruct the signal waveform. In the DSP based equivalent time sampling system, three kinds of sampling clock, frequency of which are coprime each other, are adopted to sample three times. And three groups of data are acquired. The basic frequency and other parameters of the periodic signal are estimated from three groups of data. And the periodic signal waveform is reconstructed. It has been tested by experiments that the equivalent time sampling rate of the DSP based equivalent time sampling system is 10GSps when the maximum real sampling rate of the system is 200MSps.