FPGA-Based Orthogonal–Array IMUSIC Algorithm for Robust DOA Estimation

Abstract

This paper presents an FPGA-based Improved MUSIC (IMUSIC) algorithm employing an Orthogonal–Array architecture for accurate and hardware-efficient direction-of-arrival (DOA) estimation. The proposed Orthogonal–Array enhances spatial diversity and improves subspace separation, enabling robust DOA estimation under noisy and limited-snapshot conditions. A hardware-oriented IMUSIC framework is developed to achieve high resolution while maintaining low computational complexity and resource efficiency. Performance evaluation using root mean square error (RMSE) analysis demonstrates that the proposed approach consistently outperforms conventional MUSIC, Capon, and Root-MUSIC methods and closely approaches the Cramér–Rao Bound across a wide range of signal-to-noise ratios and snapshot counts. The results confirm the suitability of the proposed FPGA-based Orthogonal–Array IMUSIC algorithm for real-time smart antenna, radar, and wireless communication applications.