Joint Direction-of-Arrival and Time-of-Arrival Estimation with Ultra-wideband Elliptical Arrays

TL;DR

This paper introduces a versatile ultra-wideband technique for joint DoA and ToA estimation using elliptical arrays, enabling flexible array configurations and robust performance in multipath wireless environments.

Contribution

The method allows for simultaneous use of elliptical, circular, and linear arrays with a unified implementation, improving signal discrimination and estimation accuracy in complex scenarios.

Findings

Accurate DoA and ToA estimations in simulations and experiments.

Robustness against noise and sensor placement uncertainty.

Flexible array configurations with improved detection performance.

Abstract

This paper presents a general technique for the joint Direction-of-Arrival (DoA) and Time-of-Arrival (ToA) estimation in multipath environments. The proposed ultra-wideband technique is based on phase-mode expansions and the use of nearly frequency-invariant elliptical arrays. New possibilities open with the present approach, as not only elliptical, but also circular and linear (highly flattened) arrays can be considered with the same implementation. Systematic selection/rejection of signals-of-interest/signals-not-of-interest in smart wireless environments is possible, unlike with previous approaches based on circular arrays. Concentric elliptical arrays of many sizes and eccentricities can be jointly considered, with the subsequent improvement that entails in DoA and ToA detection. This leads to the realization of pseudo-random array patterns; namely, quasi-arbitrary geometries created from the superposition of multiple elliptical arrays. Some simulation and experimental tests (measurements in an anechoic chamber) are carried out for several frequency bands to check the correct performance of the method. The method is proven to give accurate estimations in all tested scenarios, and to be robust against noise and position uncertainty in sensor placement.