Applications of SAW Convolvers to Spread-Spectrum Communication and Wideband Radar

Abstract

Surface acoustic wave (SAW) convolvers and support circuitry have been developed to provide matched filtering of wideband waveforms having lime-bandwidth products exceeding IO3 and continu- ously changing spreading codes for both spread-spectrum communication and wideband radar applications. For spread-spectrum Communication, additional signal processing techniques have been developed to provide correlation of waveforms having time-bandwidth products of IO6 or more with a search window of microseconds for a 100-MHz signal as well as to perform antimultipath processing for data demodulation and for ranging. For wideband radar, high-speed optoelectronic track-and-hold circuits for range gating as well as buffering and charge-coupled-device matrix- matrix-product chips for Doppler processing are being incorporated along with a SAW convolver to provide 0.75-m range resolution and 32 Doppler bins for each of 1280 range bins.