Random Triggering Based Sub-Nyquist Sampling System for Sparse Multiband Signal

TL;DR

This paper introduces RT-MWCS, a novel sub-Nyquist sampling method for sparse multiband signals that uses random triggering and modulation to achieve efficient signal reconstruction at rates below Nyquist.

Contribution

The paper presents a new random triggering based compressive sampling system that simplifies architecture and improves efficiency for sparse wideband signals.

Findings

RT-MWCS achieves accurate reconstruction at sub-Nyquist rates.

System architecture is simpler and can be implemented with a single channel.

Experimental results confirm effective reconstruction of sparse multiband signals.

Abstract

We propose a novel random triggering based modulated wideband compressive sampling (RT-MWCS) method to facilitate efficient realization of sub-Nyquist rate compressive sampling systems for sparse wideband signals. Under the assumption that the signal is repetitively (not necessarily periodically) triggered, RT-MWCS uses random modulation to obtain measurements of the signal at randomly chosen positions. It uses multiple measurement vector method to estimate the non-zero supports of the signal in the frequency domain. Then, the signal spectrum is solved using least square estimation. The distinct ability of estimating sparse multiband signal is facilitated with the use of level triggering and time to digital converter devices previously used in random equivalent sampling (RES) scheme. Compared to the existing compressive sampling (CS) techniques, such as modulated wideband converter (MWC), RT-MWCS is with simple system architecture and can be implemented with one channel at the cost of more sampling time. Experimental results indicate that, for sparse multiband signal with unknown spectral support, RT-MWCS requires a sampling rate much lower than Nyquist rate, while giving great quality of signal reconstruction.