Continuous-Transverse-Stub Arrays Empower Ka-Band Antennas

Ka-band satellite constellations have been deployed to meet the increased demand for broadband satellite-communication (satcom) systems. This band has an allocated frequency range from 17.7 to 21.2 GHz for receiving (Rx) units, while transmitting (Tx) units span 27.5 to 31.0 GHz. Both the Tx and Rx bands place stringent requirements on the antenna. To meet these, several solutions have recently been proposed. Arrays of continuous-transverse-stubs (CTSs) are a good candidate for advanced antenna systems, owing to their advanced performance and fabrication stability. By way of example, researchers from the University of Rennes 1, Sorbonne University, and the Centre National d’Etudes Spatiales (CNES) in France recently developed a CTS array for Ka-band applications.

CTS arrays, which can resemble connected arrays of slots, consist of broad stubs connected to a parallel-plate waveguide (PPW) feeding system. When the PPW structure feeds the stubs in parallel, the CTS array can achieve a very wide bandwidth and a wide scanning capability. The team designed a CTS array of 16 slots, targeting an operating frequency range of 27.5 to 31.0 GHz. A PPW corporate-feed network was utilized to feed the CTS array in parallel. The antenna achieved greater than 27.6 dBi of gain as well as efficiency in excess of 80% across the entire frequency range. See “Continuous Transverse Stub Array for Ka-Band Applications,” IEEE Transactions on Antennas and Propagation, Nov. 2015, p. 4,792.