Enhanced Direction of Arrival Estimation via Received Signal Strength of Directional Antennas

Abstract

Direction of arrival (DoA) estimation is required in civilian and military applications such as in wireless communications, search and rescue, security, law enforcement, sonar, and seismology. In the context of security and law enforcement, recently the number of accidents and incidents involving unmanned aerial vehicles (UAVs) have increased significantly with million of dollars losses being reported. Therefore, research on (DoA) estimation for the localization of intruding UAVs is crucial to develop systems to avoid these losses in the future. Previous works on (DoA) estimation via received signal strength (RSS) value used a conformal antenna array over a platonic solid geometry and applied the multiple signal classification (MUSIC) algorithm. Since MUSIC is proposed for omni directional antennas, when the antenna has a high directivity, MUSIC is no longer suitable for RSS-based algorithms. In a previous work, we proposed a novel algorithm for RSS-based (DoA) estimation. In this paper, we propose an enhanced framework using arrays of directional antennas for (DoA) estimation with the motivation of localizing drones exploiting their transmitted NTSC signal. We evaluate the performance of the proposed framework for different angular spacing between the antennas on the array. We evaluate its the performance for two different directivity gain patterns of the antennas. Finally, we validate our framework experimentally using off-the-shelf antennas and acquire signals using a software defined radio (SDR) in a measurement campaign. The experimental results show a satisfactory accuracy for the majority of our measurements.