Performance of an Axially Displaced Ellipse Reflector Antenna With Compact Monopulse Tracking Feed for a Small Aperture Transportable Terminal

• Published in: IEEE transactions on antennas and propagation Vol. 68; no. 3; pp. 2008 - 2015
• Main Authors: Kumar, B. Pavan, Kumar, Chandrakanta, Kumar, V. Senthil, Srinivasan, V. V.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2020; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna feeds; Aperture antennas; Apertures; Axially displaced ellipse (ADE); Cassegrain antennas; Diameters; Geometry; ground station antenna; monopulse tracking; Noise levels; reflector antenna; Reflector antennas; Systems design; Tracking; transportable terminal
• ISSN: 0018-926X; 1558-2221
• DOI: 10.1109/TAP.2019.2948504

Performance of an axially displaced ellipse (ADE) reflector antenna with small aperture (<inline-formula> <tex-math notation="LaTeX">\approx 33~\lambda _{0} </tex-math></inline-formula>) when integrated with monopulse tracking feed is presented for the first time in this article. The results and other system design aspects are compared with the conventional geometries like Prime Focal, Gregorian, and Cassegrain antennas indicating significant electrical and mechanical advantages for a small aperture. These enable the design of a 4.6 m-diameter compact auto-tracking ADE antenna at <inline-formula> <tex-math notation="LaTeX">S </tex-math></inline-formula>-band for deploying on a transportable terminal. The measured gain of the antenna is 37.6 dBic at 2.25 GHz, which corresponds to an aperture efficiency of about 50% and gain over noise-temperature (G/T) ratio is 15.3 dB/K. The measured null depth is 30 dB with respect to the peak for monopulse tracking. These values are very good considering the small size of the aperture and the complexity of the feed.