Forming high gain wide beam with NULL steering ability to receive UAV signal based on phased array antenna

Abstract

—Successfully achieving the mission of the unmanned aerial vehicle (UAV) requires high gain data link between the UAV and the ground control station (GCS). The antenna of the ground station must has a narrow, precisely guided beam towards the UAV. Widening the beamwidth in phased array will be on the expense of reducing the gain and increasing the possibility of receiving the interference signal, this may lead to the failure in achieving the desired link. This paper presents a new method to achieve an automatic forming of the reception beam and automatic tracking of the UAV’s signal in the digital phased array without the need of the complex digital signal processing algorithms used in smart antenna. The proposed approach is based on the complex vector multiplication and phase conjugation technique. The UAV will stay on the beak of the array factor. The resulted array is a combination between the retrodirective array and the phased array, its beamwidth equal to the field of view without reducing the gain and with null steering ability. Comparison between the array response of the proposed approach and the array response of a tracking system using the Monopulse Digital Beam Forming algorithm against different values of the phase error deviation is done.