一种增加硬件采样密度的方法研究

A method for enhancing the sampling density of data-acquisition equipment

有别于传统的多片ADC通过交替/并行采样方式提高采样频率的方法,本文应用反馈原理,采用延时器组成的单位闭环与数据采集装置串联组成一种基本采样结构。多个基本采样结构组成并行工作的采样装置时,可获得和传统方法相似的采样效果,采样频率提升倍数正比于基本结构的个数。与传统方式不同的是,对于实时性要求不强的场合,只包含单个基本采样结构的低采样装置可实现对高频信号的数据采集,采样频率的提升倍数可以任意设定,但系统完成数据采集的时间也增加相同的倍数。文中采用MATLAB仿真的方式给出了一个将硬件采样频率提升4倍的应用实例,仿真结果的频谱分析验证了方法的正确性。

Applying feedback principle, a basic sampling structure is proposed in this paper. The structure, distinguishing to traditional method of speeding up the sampling rate with interleaving/multiplexing data-acquisition, is composed of a unit closed-loop with time-delay device and a data-acquisition device in series. A sampling device which consists of several basic sampling structure working in parallel has the same performance with traditional method. Comparing with traditional method, the new method has an advantage, i.e. for the occasions with lower real-time requirement, a lower data-acquisition device including a basic sampling structure can achieve a higher sampling rate. The multiples of sampling rate can be set as required at the price of spending the same multiples of time to finish the data acquisition. A simulation example with Matlab is conducted to realize accelerating the sampling rate to 4 times of the original sampling rate with a basic sampling structure. The spectrum analysis of the simulation results of this example proved the correctness of the method.