A compact and high-gain Ka-band multibeam continuous transverse stub antenna

We present a low-profile, high-gain continuous transverse stub (CTS) array with wide-scanning capabilities. It achieves state-of-the-art performance by employing just 16 slots fed by a corporate feeding network in parallel plate waveguide technology. A pillbox coupler, based on a parabolic reflector, provides the linear source exciting the network. The beam is steered in H-plane by moving the input horn in the focal plane of the reflector. The radiated properties have been optimized in the 27.5-31 GHz band, but are stable up to 40 GHz. In the targeted band, the antenna is matched below -15 dB and the efficiency is > 80% within a ±30° scanning range. For broadside operation at 29.25 GHz, efficiency and peak gain are 93% and 28.9 dBi, respectively. This design represents a flat and cost-effective solution for high-performance Satcom Ka-band terminals and mobile ground stations.