MUSIC and improved MUSIC algorithm to estimate direction of arrival

The DOA estimation in array signal processing is one of the important and emerging research area. The effectiveness of this direction of arrival estimation greatly determines the performance of smart antennas. It works on the digitized output from each sensor array. The estimation results for coherent signals, broadband signals and multiple signals are of greater consideration. Various information of the parameters relating to a particular wave can be obtained by analyzing the incoming wave that is received by a sensor or an array of sensors. The accuracy in the estimation of direction of arrival is very crucial in array signal processing. DOA estimation has vital applications in radar, sonar, seismology, earthquake, astronomy, biomedicine and communication. This paper presents an overview of direction of arrival estimation using the MUSIC algorithm. This algorithm is a peak search method to estimate the arrival angle. The paper emphasizes on the factors that can affect the results of the estimation process and describes the concept of estimating the arrival angle. The MATLAB simulations shown here highlight the factors that can improve accuracy. The factors include the array element spacing, number of array elements, number of snapshots and the signal incidence angle difference. Attempts are made to bring about better resolution and contrast. As the conventional MUSIC algorithm is found to have less efficiency for coherent signals, better simulations using an improved MUSIC algorithm in provided in this paper.