DOA Estimation of Wideband Signals

For many applications, wideband signals are exploited for localization. A wideband signal is any signal whose energy is distributed over a bandwidth that is large in comparison to the signal’s center frequency. For example, ultrawideband (UWB) noise radars use wideband offering low probability of detection (LPD), while achieving good target detection and high resolution [1]. In the acoustic vehicle tracking scenario, the target emits a set of narrowband harmonics [2]. Direct exploitation of an array of raw wideband signals for localization using traditional narrowband techniques will fail miserably. The shortcoming is that the narrowband methods exploit the fact that time delays directly translate to a phase shift in the frequency domain [3].