Efficient sampling of sparse wideband analog signals
Efficient sampling of sparse wideband analog signals
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DOI：
10.1109/eeei.2008.4736707
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发表时间：
2008-03
期刊：
影响因子：
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通讯作者：
M. Mishali;Yonina C. Eldar;J. Tropp
中科院分区：
文献类型：
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作者：
M. Mishali;Yonina C. Eldar;J. Tropp
周期性非均匀采样是对低于奈奎斯特速率的频谱稀疏信号进行采样的已知方法。该策略依赖于隐含的假设，即各个采样器暴露于整个频率范围。这种假设对于宽带稀疏信号变得不切实际。本文提出了一种不需要全频带前端的替代采样级。相反，信号是用模拟前端捕获的，模拟前端由一组乘法器和低通滤波器组成，其截止频率远低于奈奎斯特频率。从低速率采样恢复原始信号的问题可以在压缩采样的框架内进行研究。适当的参数选择可确保样本唯一确定模拟输入。此外，模拟输入可以用数字算法稳定地重构。数值实验支持了理论分析。
Periodic nonuniform sampling is a known method to sample spectrally sparse signals below the Nyquist rate. This strategy relies on the implicit assumption that the individual samplers are exposed to the entire frequency range. This assumption becomes impractical for wideband sparse signals. The current paper proposes an alternative sampling stage that does not require a full-band front end. Instead, signals are captured with an analog front end that consists of a bank of multipliers and lowpass filters whose cutoff is much lower than the Nyquist rate. The problem of recovering the original signal from the low-rate samples can be studied within the framework of compressive sampling. An appropriate parameter selection ensures that the samples uniquely determine the analog input. Moreover, the analog input can be stably reconstructed with digital algorithms. Numerical experiments support the theoretical analysis.