DOA estimation of ultra wideband signals using multiple constant beamwidth beamformers

Direction-of-arrival (DOA) estimation for ultra wideband (UWB) array has received considerable attention in high-precision UWB localization. A novel beamspace-based DOA estimation method for UWB signals is proposed in the paper by designing multiple constant beamwidth beamformers. The bandwidth of UWB signal is decomposed into several narrowband bins. The array response vectors at different frequency bins are transformed into the one at reference frequency. Chebyshev weight and discrete Fourier transform (DFT) weight are used as the beamforming weights at reference frequency, respectively. Then multiple constant beamwidth beamformers are designed using frequency invariant beamforming method, and DOA estimation method in beam space is given. In the simulations, the impact of different parameters is also discussed.