An Overview of Direction-of-arrival Estimation Using an Antenna Array with Four Elements

The Direction-of-Arrival (DOA) estimation techniques using antenna arrays are applied in large areas of research fields and have received great attention in literature. Mobile communication, Sonar and Radar are just some examples among a large number of possible applications. For example, in military application, it is very important to recognize the direction of any threat. Another example of commercial application is to identify the direction of an emergency cell phone call so that the rescue unit can act in time to the right location. Thereby, DOA estimation using a traditional fixed antenna has many limitations and becomes inappropriate in such applications. In this letter, we describe a DOA estimation system based on an antenna array and five port circuits for detecting arrival angles in azimuth plane of signals pitched by the antenna array. For this, we have based on Multiple Signal Classification (MUSIC) algorithm, which showed a certain limit of its performance in spite of its big reputation by the researchers. In our case, we only consider uncorrelated signals and assume the channel parameters corresponding to a real context. The purpose is to compare the quality of the detected angle in term of precision depending on the number of the samples depicted. ADS software and MATLAB are used to achieve this study. The simulation results on the proposed system designed to operate at 2.4 GHz frequency indicate that MUSIC algorithm is unable to automatically detect and localize the DOA of signals with high accuracy. Other algorithms exist and may provide more precision but require more computation time.