S-band Steerable Yagi Antenna for CubeSats
In this paper, a steerable Yagi-Uda antenna implemented on a dielectric is proposed for S-band CubeSat communications. The steerable Yagi antenna consists of 3 elements lying on an FR4 substrate that form an angle with the CubeSat's surface. The key idea is to mechanically control the angle between the proposed antenna and the CubeSat's surface to achieve steerability and hence establish inter-satellite link. A scanning angle of 60 degrees can be achieved which could potentially support a variety of CubeSat missions. The proposed antenna was simulated using HFSS to show its steerability and S11 and radiation pattern measurements were carried out. The simulation results show that the antenna provides a maximum gain of 8.877dB and reflection coefficient of -16.73dB at 2.45GHz with a -10dB bandwidth of 250MHz. The measured reflection coefficient is -14.6dB with -10dB bandwidth of 200 MHz at a resonant frequency of 2.45GHz. The radiation pattern of the fabricated antenna was measured in the anechoic chamber located at the University of Wollongong and compared with the simulation results.