X-Band Archimedean Spiral Antenna Array with Sloped-Wall Backing Cavity

An Archimedean Spiral Antenna Array with Sloped-Wall Backing Cavity was designed to achieve the broad bandwidth with high gain, circular polarization, and low-profile configuration for X-band (8-12 GHz) Deep Space communications for CubeSats. The designed 2 by 2 array showed good impedance matching and a low axial ratio (<; 3 dB) from 8 to 12 GHz. The addition of the slope-wall backing cavity increases the realized gain of the Archimedean Spiral Antenna by greater than 3.2 dBiC across the frequency band without the drop in gain experienced by conventional cavities. The designed array fits on the 1U (100 x 100 mm
²
) face of the CubeSat.