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.

The large adaptive reflector: a 200-m diameter wideband centimeter- to meter-wave radio telescope

Abstract: The Large Adaptive Reflector (LAR) is a concept for a low- cost, large aperture, wideband, radio telescope, designed to operate over the wavelength range from 2 m to 1.4 cm. It consists of a 200-m diameter actuated-surface parabolic reflector with a focal length of 500 m, mounted flat on the ground. The feed is held in place by a tension-structure, consisting of three or more tethers tensioned by the lift of a large, helium-filled aerostat -- a stiff structure that effectively resists wind forces. The telescope is steered by simultaneously changing the lengths of the tethers with winches (thus the position of the feed) and by modifying the shape of the reflector. At all times the reflector configuration is that of an offset parabolic antenna, with the capability to point anywhere in the sky above approximately 15 degree Elevation Angle. At mid-range wavelengths, the feed is a multi-beam prime-focus phased array, about 5 m diameter; at meter wavelengths, it is a single-beam phased array of up to 10 m diameter. Simulations have shown that in operating wind conditions (10 m/s average speed with 2.5 m/s gusts), the position of the feed platform can be stabilized to within a few cm over time scales of approximately 20 s. Research indicates that the telescope concept is feasible and that an order of magnitude improvement in cost per m2 of collecting area over traditional designs of large parabolic antennas can be achieved.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Corrugated horn radiator

Abstract: A corrugated horn radiator which includes a transition zone made up of a number of parts between the smooth-wall feed wave guide 1 having a cross-section which is constant and a horn radiator with regular periodic corrugations 10 with the depth of the corrugations being less than one-quarter wave length relative to the lowest frequency to be transmitted. The transition zone starting at the constant diameter feed wave guide comprises a first section which is conical shaped and then joins a second section which is cylindrical in shape and which serves as a phase drift space and then connects to a second conical smoothed walled portion and then connects to an exponential horn having a pair of corrugations with re-entrant ring-shaped ends (6, 7) which are narrower than the regular periodic corrugation structure 10. The pair of corrugations 6 and 7 connect with a corrugated transition section 8 which comprises a plurality of corrugations which have depths that become progressively less as they approach the regular corrugations 10 and wherein the apex angle of the transition portion 8 is greater than the apex angle of the regular corrugation portion 10. The corrugated horn radiator of the invention has good broad band characteristic and favorable broad band cross-polarization characteristics and the corrugated horn radiator can be employed as a horn antenna or as a feed horn for a Cassegrain or focus fed antenna.

Three dimensional feed through lens with hemispherical coverage

Abstract: A lens antenna (10) having four phased array apertures (12, 14, 16, and 18) positioned for hemispherical coverage is disclosed. An array of phase shifters (52) is disclosed, each of which is interconnected with four radiating elements (54, 56, 58, and 60), one on each of the four apertures. A feed horn (30) is used to feed the lens and switches (48, 50) in the lens are used to switch the energy received from the feed horn to the phase shifter, and after phase shifting, to a selected aperture for radiation. The switches also perform a reciprocal function by switching energy received at an aperture to the phase shifter and then to an aperture for radiation to the feed horn. In a further embodiment, the mounting of transmitting and receiving components, such as a high power amplifier (70) and a low noise amplifier (72), with a combination of DPDT switches in the lens is disclosed and results in a solid state T/R type antenna array. In one embodiment, the switches enable the lens to radiate from three of the apertures for a scan angle of 270 degrees from a single feed horn. The addition of mor efeed horns per face results in multiple radiated beams from a single face.

Dual channel 115 and 230 GHz SIS receivers in operation at the Owens Valley Radio Observatory

Abstract: The Owens Valley Radio Observatory millimeter-wave interferometer array is presently operating with dual-channel SIS (superconductor-insulator-superconductor) tunnel junction receivers. The first channel covers the frequency range from 85 to 120 GHz and the second channel covers the frequency range from 200 to 300 GHz. The mixers consist of a corrugated feed horn, a single-stage circular-to-rectangular waveguide transition a reduced-height waveguide with an SIS junction mounted across the E-plane, and a non-contacting backshort. The mixer block has a built-in RF choke for the IF (intermediate frequency) signal path which is designed to present a short circuit to the junction at frequencies above the 2-GHz IF frequency. The small-area ( >

Ground terminal antenna for Ka-band satellite communications

Abstract: This paper presents a new low-cost antenna intended for moving platforms like planes, high-speed trains or buses, allowing communications with Ka-band satellites Beam scanning capability covers the range from 0° to 65° in elevation and 360° in azimuth The antenna structure is composed by a horn with a 45° slant aperture and a shaped dielectric lens that tilts and rotates in front of the horn to direct the beam, providing simple mechanical steering Scan loss in the elevation plane is of the order of 3 dB