RSSI-Based Heading Control for Robust Long-Range Aerial Communication in UAV Networks

Directional antenna-based aerial networking (DAAN) is referred as a promising technology to meet the dynamic data demands for unmanned aerial vehicles (UAVs). However, the narrow radiation pattern of directional antennas and the mobility of UAVs make it challenging to form a robust DAAN. This paper presents a heading control strategy for UAV-carried directional antennas to establish a robust long-range aerial communication channel. The heading control process is mainly divided into two phases, i.e., position estimation and angle adjustment. In the first phase, a proportional-derivative-based tracking controller is designed for each UAV to ensure the consistency of heights, pitch, and roll angles. Particularly, the received signal strength indicator is adopted as an auxiliary measuring component, and then a consensus-based unscented Kalman filtering algorithm is developed to estimate the position of UAVs. With the estimated position information, a feedback-based heading controller is designed for directional antenna in the second phase to enable robust long-range aerial communication channel. Moreover, the convergence conditions and Cramer-Rao lower bounds are also provided. Finally, simulation results are presented to demonstrate the effectiveness of the proposed strategy. It is shown that the influence of malicious measurements can be reduced, and the signal strength can be significantly improved as compared with the omni-directional antenna-based works.