Directional-of-Arrival Estimation for A Novel Non-uniform Linear Array

Non-uniform linear arrays (NLAs) usually have the ability to form a larger array aperture than conventional uniform linear arrays (ULAs) with the same number of sensors. In this paper, we proposed a directional-of-arrival (DOA) estimation scheme for a novel kind of NLA, in which sensors are placed in a quadratic rule instead of the equal interval in ULAs. In this way, the received signal of the NLA of a single snapshot can be taken as an LFM signal, and consequently the DOA estimation problem can be cast as the LFM parameters estimation problem. Next, the fractional Fourier transform (FrFT) is employed to estimate the DOAs of the sources together with the CLEAN strategy. Finally, various simulations are carried out and results are shown to verify the performance of the proposed DOA estimation method for this novel NLAs.