High Resolution Joint Angle and Delay Estimation Using IEEE 802.11ac

Joint angle and delay estimation (JADE) has become a key technique for accurate localization in dense multipath indoor scenarios. This paper addresses the problem of JADE for multiple reflections of a multi-carrier signal impinging on multiple-antenna system. Inspired by the Minimum Variance Distortionless Response (MVDR), we propose an efficient spectral method for this problem. The proposed method is a high resolution estimator which only need two-dimensional search. Unlike the maximum likelihood JADE estimator, the number of paths is not required known a prior. Furthermore, the smoothing technique and diagonal loading technique are exploited to construct reasonable sample covariance matrix. Simulation results using the IEEE 802.11ac standard's setup parameters are provided to validate the proposed method's effectiveness. At a low or medium signal-to-noise ratio (SNR), the performance of the proposed method is superior to the MUSIC-JADE algorithm with path number estimation.