Xampling: Analog Data Compression

Abstract

We introduce Xampling, a design methodology for analog compressed sensing in which we sample analog bandlimited signals at rates far lower than Nyquist, without loss of information. This allows compression together with the sampling stage. The main principles underlying this framework are the ability to capture a broad signal model, low sampling rate, efficient analog and digital implementation and lowrate baseband processing. In order to break through the Nyquist barrier so as to compress the signals in the sampling process, one has to combine classic methods from sampling theory together with recent developments in compressed sensing. We show that previous attempts at sub-Nyquist sampling suffer from analog implementation issues, large computational loads, and have no baseband processing capabilities. We then introduce the modulated wideband converter which can satisfy all the Xampling desiderata. We also demonstrate a board implementation of our converter which exhibits sub-Nyquist sampling in practice.