Improved unitary root-MUSIC for DOA estimation based on pseudo-noise resampling

Abstract—A novel pseudo-noise resampling (PR) based unitary root-MUSIC algorithm for direction-of-arrival (DOA) estimation is derived in this letter. Our solution is able to eliminate the ab-normal DOA estimator called outlier and obtain an approximate outlier-free performance in the unitary root-MUSIC algorithm. In particular, we utilize a hypothesis test to detect the outlier. Mean-while, a PR process is applied to form a DOA estimator bank and a corresponding root estimator bank. We propose a distance de-tection strategy which exploits the information contained in the es-timated root estimator to help determine the final DOA estimates when all the DOA estimators fail to pass the reliability test. Fur-thermore, the proposed method is realized in terms of real-valued computations, leading to an efficient implementation. Simulations show that the improved MUSIC scheme can significantly improve the DOA resolution at low signal-to-noise ratios and small samples. Index Terms—Direction-of-arrival (DOA) estimation, pseudo-noise resampling (PR), small sample size, unitary root-music. I