A New Patch Antenna Designed for CubeSat: Dual feed, L\/S dual-band stacked, and circularly polarized

This article describes a dual-feed, L/S-dual-band-stacked, circularly polarized (CP) patch antenna designed for CubeSat. The antenna is formed by three layers and includes a stacked, dual-band patch antenna on the top and a metallic ground with an embedded feeding network at the bottom. Four stubs are symmetrically added around the periphery of each square patch to tune the operating frequency. The feeding network is made of two independent 3-dB branch-line hybrid couplers formed by striplines. A prototype of the designed antenna has been fabricated and measured. Simulated results show good agreement with measured results. Measured return loss is well below -15 dB, while the axial ratio (AR) is better than 2 dB at both operating frequency bands. Moreover, the measured half-power beamwidth (HPBW) exceeds 80? for both working frequencies. Space environment testing procedures were conducted and demonstrated high reliability and antenna stability.