Code properties analysis for the implementation of a modulated wideband converter

This paper deals with the sub-Nyquist sampling of analog multiband signals. The Modulated Wideband Converter (MWC) is a promising compressive sensing architecture, foreseen to be able to break the usual compromise between bandwidth, noise figure and energy consumption of Analog-to-Digital Converters. The pseudorandom code sequences yielding the sensing matrix are yet the bottleneck of it. Our contributions are multifold: first, a proposal of a new Zadoff-Chu code based real-valued sensing matrix that satisfies cyclic properties and good spectral properties and increases robustness against noise. Second, a quasi systematic study of the influence of code families and of row selection is carried out on different criteria. Especially, the influence on the coherence, vital to limit the number of branches, is investigated. Additionally, an original approach that focuses on evaluating isometric properties is established. These measures are helpful since isometry is essential to noise robustness. Third, the relevance of previous high-level metrics is validated on various codes thanks to a simulation platform. Altogether this study delivers a methodology for a thorough comparison between usual compressive sensing matrices and new proposals.