True time delay beamspace wideband source localization

Abstract

A novel method for signal subspace processing in the beamspace of a true time delay (TTD) beamformer bank is presented. The method permits the directions of arrival of broadband sources to be estimated accurately, efficiently and non-iteratively. This is achieved by exploiting the properties of the TTD beamformer bank, which simultaneously introduces spatial diversity into the data set while maintaining the broadband nature of the data. The beamspace manifold is derived and simulation results are presented. The method is shown to improve on the processing efficiency of previous broadband methods while maintaining source location estimation accuracy superior to conventional methods. It is also shown to resolve closely spaced and disparately spaced sources in a single algorithmic pass. The method is compared to previous method in terms of bias and RMSE.