V-Band “Bull´s Eye” Antenna for CubeSat Applications

We simulate and measure the radiation pattern of a V-band “Bull´s eye” antenna for communication between CubeSats. We also propose a modification that allows the beam direction to be arbitrarily chosen over a ±20° range, useful for swarms where CubeSats must communicate with more than one neighbor. The “Bull´s eye” antenna offers high gain in a low profile, which makes it readily integrable into a CubeSat chassis. We study the relationship between the number of indented rings, and overall gain, for emission along the boresight, finding seven rings is optimal. Anechoic chamber pattern measurements show good agreement between measurement and simulation for both E-plane and H-plane. The simulated gain is 19.1 dBi at the intended operating frequency of 60 GHz, and is better than 16.7 dBi over the 5.06-GHz bandwidth, with a 19.7-dBi peak gain, and the resonant frequency is centered at 60.08 GHz with S₁₁-parameter of -55.4 dB. We simulate designs with center-shifted rings, indicating smoothly increasing beam deflection with ring offset, and maximum deflection of 19.8° (16.1°) in E-plane (H-plane) at the maximum shift of one indentation width.