Joana S. Silva

Tx-Rx Lens-Based Satellite-on-the-Move Ka-Band Antenna

A simple low-cost mobile ground terminal antenna for Ka-band satellite communications is presented. The antenna is composed of a shaped dielectric lens which tilts and rotates in front of a feed to direct the beam. The wideband feed system is composed of a quad-ridged horn with a 45° slant aperture and a coaxial-to-quad-ridged circular waveguide transition. The lens allows simple mechanical beam steering from 0 ° to 65 ° in relation to the zenith and 360 ° in azimuth by rotating both the lens and the feed slanted aperture. Performance measurements of a manufactured prototype prove the beam tilting capabilities in elevation with a maximum gain of 22 dBi and scan loss below 3 dB at 20 GHz and 24 dBi gain with less than 4.5 dB scan loss at 30 GHz.

A planar feed for SOTM Ka-band lens antennas

Ka-band satellite technology has been drawing growing interest from public transportation industry to military applications, due to its advantages of higher speed links, smaller terminals and reduced costs. These well-recognized characteristics have also boosted the interest in exploiting the Ka-band devices for personal use in small boats or all-terrain vehicles. This paper presents a simple, low-cost and compact mobile ground terminal antenna useful for satellite communications on-the-move (SOTM) applications. The system operates in the downlink Ka band (19.7 - 20.2 GHz). It consists of a shaped dielectric lens fed by a circularly polarized (CP) patch antenna. The lens system allows a mechanical beam steering from 0° to 57° in relation to the zenith, with a scan loss below of 4.5 dB. A comparison is provided between this system and a previous one using the same lens but fed by a horn antenna, demonstrating the potential of planar structures as low profile feeders for SOTM lens antennas.