Iterative interpolar based switched element direction finding for wideband linear frequency modulated signals

This paper proposes an iterative algorithm to estimate the direction of arrival (DOA) of wideband linear frequency modulated (LFM) signals based on the switched element direction finding (SEDF) technique. Starting from the evidence that traditional DOA estimation algorithms designed for narrowband signals suffer for a performance loss when the chirp rate is large, we propose a fast-iterative interpolation algorithm that exploits both the fractional autocorrelation spectrum and the discrete-time fractional Fourier spectrum, to mitigate the dispersion effect. Numerical simulations corroborate the feasibility and validity of proposed algorithm.