Feed horn

About: Feed horn is a research topic. Over the lifetime, 2395 publications have been published within this topic receiving 26548 citations. The topic is also known as: feedhorn.

Ka-Band Shaped Reflector Hybrid Antenna Illuminated by Microstrip-Fed Horn Array

Abstract: The numerical simulation and experimental results of a shaped reflector hybrid antenna (SRHA) structure are presented. The SRHA design was optimized for a scan range of plusmn3deg for a broadside of 45deg in elevation to maintain a gain of more than 38 dBi and low side-lobes. The designed SRHA has an aperture size of less than 60 times 70 m2 and an offset structure for a low profile to meet the need for a mobile satellite platform. The antenna geometry and reflector surface was determined by a geometrical optic (GO) method and the radiation pattern was obtained by physical optic (PO) analysis. A microstrip horn array was used as a feeder and was composed of eight elements. The number of array elements was chosen so as to maximize antenna performances, such as gain and efficiency, without overdesign. The SRHA breadboard, including a shaped reflector and a feed horn array, was fabricated and measured. The measured results showed good agreement with the simulation and met the performance required of SRHA.

Method and apparatus for automatically identifying an antenna connected to a radio transmitter and for automatically controlling a transmitter

Abstract: A transmission system or apparatus includes a transmitter or source of transmitted RF or microwave power which is selectively connectable via a transmitter connector to an antenna having an antenna feed via an antenna connector so that a variety of antennas with differing characteristics can be used with a given transmitter. Each antenna preferably has a marker or indicating element incorporated into the antenna feed. The marker or indicating element includes a physically measurable property or parameter corresponding to a physical characteristic of the attached antenna. In the preferred embodiment, the indicating element is a resistance connected in parallel with the antenna feed and having a selected resistance value (e.g., in ohms) which indicates the physical characteristic of gain for antenna. The transmission system also includes an indicating element sensor configured to sense or measure the marker or indicating element and generate a transmitter control signal in response to that measurement. The method for automatically generating the control signal can be implemented in programmable steps as computer software and may include use of a Look Up Table (LUT) having a range of indicator element characteristic values and a range of corresponding transmitter control signal values or, alternatively, can include use of a computation sequence which takes an indicator element characteristic value as an input variable and generates a control signal value in response thereto.

Antenna arrangement for providing a frequency independent field distribution with a small feedhorn

Abstract: The present invention relates to an antenna arrangement which uses an imaging reflector (10) combined with a small feed or horn (14) which is capable of launching or receiving a spherical wavefront (18) to obtain a nearly frequency independent field distribution over a large antenna aperture. The antenna arrangement comprises a parabolic main reflector (10) disposed confocally with one focal point of a subreflector means (12) and a feed (14) disposed with the apex of the spherical wavefront at the other focal point of the subreflector means and the aperture of the feed centered on the image of the main reflector. If the rim of the feed aperture corresponds to an image of the edge of the main reflector, spill-over is substantially eliminated. Generally, any feed arrangement comprising a feed and subreflector means which transforms a spherical wavefront from the feed into a spherical wavefront emanating from the focal point of the parabolic main reflector can be used.

Method of forming a feed horn

Abstract: A method of forming a plastic microwave feed horn by first forming a mandrel which is thereafter incorporated into a mold apparatus.

Cassegrain Systems

Abstract: The effective F/D ratio for a parabolic-hyperbolic (Cassegrain) antenna system is shown under practical considerations to be only slightly larger than that of the parabola alone. Furthermore, when advantage is being taken of this increase in effective F/D ratio for the purpose of providing wider angle multiple beam antenna systems, it is shown that the size of the feed horn structure may become prohibitive.