Robust Direction of Arrival Estimation using Multiple Signal Analysis

Abstract

Direction of arrival (DOA) estimation is one of the focal problems in the fields of Wireless communications, Radar, Sonar, Radio Astronomy and Seismology. The main objective of the DOA estimation is to obtain the desired signals direction as well as the interference signals direction based on the data received from the array sensor at the base station. In literature various techniques are researched for DOA estimation. Among which are two high resolution algorithms, viz. MUSIC (MUltiple SIgnal Classification) and ESPRIT (Estimation of Signal Parameters via Rotational Invariance Technique, MUSIC algorithm is implemented in this paper with Empirical Mode Decomposition technique. The key feature of EMD is to decompose a signal into sum of intrinsic mode functions (IMF) with a final residue of non linear and non stationary signals. The work presented in this paper deals with EMD application to the problem of DOA estimation as a preprocessing technique. This technique separately de-noises the rows of the array data matrix where each row corresponds to the output of a particular sensor array. Especially in low-SNR conditions, the estimation performance of MUSIC algorithm is enhanced significantly when de-noising is given to array data matrix prior to DOA estimation stage.