Wen Weifeng, Yan Haoyue, Zhao Yijiu, Liu Dan, He Hui
Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621999, China.
School of Automation Engineering, University of Electronic Science and Technology of China, Chengdu 611731, China.
Rev Sci Instrum. 2019 Jul;90(7):074706. doi: 10.1063/1.5110266.
A sub-Nyquist coprime sampling system for sparse signals is implemented in this article. The proposed system is composed of coprime sampling hardware and a multicoset signal reconstruction algorithm. A pair of uniform samplers is utilized in the hardware to sample a wideband spare analog signal with an uncertain difference in start times. A time difference acquisition module embedded into a field-programmable gate array and a pulse-expanding circuit are then used to measure the difference in start times. Owing to the different frequencies of the two samplers, the coprime sample sets obtained are nonuniform. Before they are used as input to the multicoset signal reconstruction algorithm, these coprime sample sets need to be regrouped into multicoset sample sets according to the sample pattern. The results of experiments indicate that the signals can be reconstructed at an equivalent rate of the order of gigahertz from sub-Nyquist samples acquired by the designed coprime acquisition system.
本文实现了一种用于稀疏信号的亚奈奎斯特互质采样系统。所提出的系统由互质采样硬件和多集信号重构算法组成。硬件中使用一对均匀采样器对具有不确定起始时间差的宽带稀疏模拟信号进行采样。然后，嵌入现场可编程门阵列的时间差采集模块和脉冲扩展电路用于测量起始时间差。由于两个采样器的频率不同，所获得的互质样本集是非均匀的。在将这些互质样本集用作多集信号重构算法的输入之前，需要根据采样模式将它们重新组合成多集样本集。实验结果表明，通过所设计的互质采集系统采集的亚奈奎斯特样本能够以千兆赫兹量级的等效速率重构信号。
