Quantization-Loss Analysis for Array Signal-Source Localization

This work investigates the problem of low SNR signal-source localization with an array of sensors. Keeping the receive system simple, we focus on analog-to-digital converters (ADC) with coarse resolution. In order to increase the localization accuracy and minimize the size of the receiver, we discuss the effect of analog filtering and antenna spacing on the Fisher information measure. In particular, the beneficial influence of temporal and spatial noise correlation produced by the analog receive filter and antenna coupling is considered. Results for the extreme case of 1-bit hard-limiting quantizers show that it is possible to compensate the quantization-loss of the optimum unbiased estimator through the correct choice of the analog frontend and antenna design. Further, our investigation shows that for array receivers high resolution parameter estimation is still possible with antenna spacings far below lambda=2.