Fourier Domain Synthesis Imaging Using A Wirelessly Coordinated Distributed Antenna Array

In this work we present an experimental demonstration of one-dimensional Fourier-domain imaging using a fully-digital wirelessly coordinated coherent distributed antenna array (CDA) receiver. The nodes consist of two software-defined radios (SDRs) operating with independent system clocks performing wireless time, frequency, and phase coordination without a shared reference such as the global navigation satellite system (GNSS). Two spatially separated noise sources transmit independent noise waveforms with a bandwidth of 25 MHz and a carrier frequency of 915 MHz. Two sources were positioned at angles of $-6.28°$ and $12.95°$ off broadside and imaging was performed. The two sources are clearly resolved to within $3°$ of their expected locations in both the individual and combined source measurements and demonstrating the Fourier-domain image reconstruction principle using a fully-digitally coordinated distributed antenna array.