A Low-Profile UHF SATCOM Antenna

A low-profile circularly polarized stacked patch antenna with U-slots was designed, fabricated, and measured at 240-300 MHz for satellite and communications applications. U-slots on the driven patch are proposed, and its design is optimized to improve the bandwidth of the antenna. In addition, the -10 dB return loss has been compromised in favor of a wider, stable, and acceptable performance bandwidth. The proposed antenna has a size of 0.36λ_c × 0.36λ_c × 0.035λ_c. A bandwidth of 22% and gain of 3.5 dBiC with axial ratio below 2.5 dB are achieved in the 240-300 MHz band.