Multi-rate asynchronous sampling of bandwidth-limited signals

TL;DR

This paper presents an experimental optical system capable of asynchronously under-sampling multiple unknown bandwidth-limited signals within 0-18 GHz using multi-rate sampling and wavelength division multiplexing.

Contribution

It introduces a novel optical system employing multi-rate asynchronous sampling and wavelength division multiplexing for broad-bandwidth signal acquisition.

Findings

Successful reconstruction of phase and amplitude of signals

Effective under-sampling of signals in 0-18 GHz range

Use of optical components for high-frequency sampling

Abstract

We demonstrate experimentally an optical system for under-sampling several bandwidth limited signals with carrier frequencies that are not known apriori that can be located anywhere within a very broad frequency region between 0-18 GHz. The system is based on under-sampling asynchronously at three different sampling rates. The pulses required for the under-sampling are generated by a combination of an electrical comb generator and an electro-absorption modulator. To reduce loss and improve performance the implementation of the optical system is based on a wavelength division multiplexing technique. An accurate reconstruction of both the phase and the amplitude of the signals was obtained when two chirped signals generated simultaneously were sampled.