Performance Comparison of Omni and Cardioid Directional Microphones for Indoor Angle of Arrival Sound Source Localization

The sound source localization technology brings the possibility of mapping the sound source positions. In this paper, angle-of-arrival (AOA) has been chosen as the method for achieving sound source localization in an indoor enclosed environment. The dynamic environment and reverberations bring a challenge for AOA-based systems for such applications. By the acknowledgement of microphone directionality, the cardioid-directional microphone systems have been chosen for the localization performance comparison with omni-directional microphone systems, in order to investigate which microphone is superior in AOA indoor sound source localization. To reduce the hardware complexity, the number of microphones used during the experiment has been limited to 4. A localization improvement has been proposed with a weighting factor. The comparison has been done for both types of microphones with 3 different array manifolds under the same system setup. The comparison shows that the cardioid-directional microphone system has an overall higher accuracy.