Cassegrain antenna

About: Cassegrain antenna is a research topic. Over the lifetime, 3207 publications have been published within this topic receiving 28278 citations.

Parabolic cylindrical reflector antenna at 60 GHz with line feed in gap waveguide technology

Abstract: A parabolic cylindrical reflector antenna is proposed in this paper for wireless multi-gigabit communications at 60 GHz. The line feed is realized by a power distribution in parallel plate waveguide (PPW). Inside the PPW waveguide there are metal pin rows forming the contours of an H-plane horn structure in front of a parabolic reflector, where we see possible mechanical advantages in not requiring metal contact of the pins to more than one metal plate. They will still work as a total reflecting wall by making use of the same stopband features as in gap waveguide technology. The result is a low loss, low cost and very versatile 60 GHz antenna with high gain. The electrical design for maximum aperture efficiency and minimum loss is explained.

Loss-free scanning antenna

Abstract: A system for, and a method of, scanning a collimated beam of electromagnetic radiation with a very large primary reflector of an antenna system without loss (ie, with zero phase error) and without moving the primary reflector The system is a two dimensional scan, loss-free, Cassegrain antenna system which comprises a stationary, parabolic-shaped, primary reflector, and a smaller, movable, parabolic-shaped subreflector, and also a movable, plane wave, electromagnetic radiation beam source interposed between the two reflectors It is shown that, without moving the primary reflector, the beam can be scanned over wide angles with no phase error in the plane of scan, provided that the source and the subreflector are rotated about the focal point of the antenna in a specific manner A unique angular relationship between the source and the subreflector is required for each scan angle, and is taught The method includes the step of using this antenna system in scanning the beam from the primary reflector, without any phase error and without moving the primary reflector

Surface accuracy measurement of a deployable mesh reflector by planar near-field scanning

Abstract: Using a near-field antenna measurement facility, it is possible to simultaneously evaluate the surface accuracy of a reflector antenna as well as the far-field pattern of the antenna for a short time. The surface errors of a 2-m deployable mesh reflector for satellite use were measured by a planar near-field system. As a result, the influence of periodic structures, due to the antenna ribs, is clearly observed. Also, the surface accuracy obtained with the near field scanning technique coincides well with that obtained by an optical measurement technique. >

Co-located multi-band antenna

Abstract: A multi-band reflector antenna having a main reflector, a sub reflector, a first feed and a second feed. The first feed, the sub reflector and the main reflector positioned in a Gregorian optic configuration wherein an output of the first feed is directed to the sub reflector, from the sub reflector to the main reflector and from the main reflector into a first beam. The sub reflector may be shaped to distribute the output of the first feed reflecting off the sub reflector onto the main reflector whereby a central area of the main reflector has a lower illumination than a surrounding outer area of the main reflector and or elongated vertically. The second feed projecting from a hole in the sub reflector is oriented whereby an output of the second feed is directed to the main reflector and from the main reflector into a second beam.

Reflector, an antenna using a reflector and a manufacturing method for a reflector

Abstract: The present invention relates to a reflector (20; 30; 40) for use in an antenna (10; 50). The reflector (20; 30; 40) is arranged to be used as an earth plane of the antenna (10) and the reflector is corrugated to form current pockets. The reflector (20; 30; 40) comprises at least two separate parts (21, 22; 21, 22, 31, 32; 41, 42), and the parts are electrically coupled to each other to commonly form the earth plane of the antenna (10; 50). The invention also relates to an antenna including a reflector, and to a method for manufacturing a reflector.