Reflector (antenna)

About: Reflector (antenna) is a research topic. Over the lifetime, 28730 publications have been published within this topic receiving 212618 citations.

Astromesh™ deployable reflectors for ku- and ka-band commercial satellites

Abstract: The potential for the AstroMesh deployable mesh reflectors to support Ku- and Ka-band commercial satellite missions is investigated. The focus of the work is on predicting reflector gain/loss for 6-meter aperture point designs operating at 14 GHz and 30 GHz. The use of RMS surface errors from both systematic and random sources for gain/loss estimates via Ruze is shown to be accurate, and grating lobe performance for the systematic components is shown to be acceptable. Mesh reflectivity performance is given and total loss estimates for viable Ku- and Ka-band point designs are presented.

Semiconductor laser with integral spatial mode filter

Abstract: A semiconductor laser having a light amplifying diode heterostructure with a flared gain region in an external resonant cavity. The flared gain region has a narrow aperture end which may be coupled to a single mode waveguide and a wide output end. A light emitting surface of the heterostructure proximate to the wide end of the flared gain region is partially reflective and combines with an external reflector to form a resonant cavity that is effectively unstable. The intracavity light-emitting surface proximate to the narrow aperture end is antireflection coated. The external reflector may be a planar mirror or a grating reflector. A lens or an optical fiber may couple the aperture end of the flared gain region to the external reflector. Frequency-selective feedback is provided by orienting the grating reflector or providing a prism in the cavity in front of the external planar mirror. Other filtering elements may also be placed in the external cavity. The flared gain region and waveguide may be differentially pumped or modulated with current provided by separate contacts.

Solar energy plant

Abstract: A solar radiation concentrating system (1) comprises at least two reflectors (12, 16) successively arranged along an optical path (4) of the system (1) so that a first (12) of the two reflectors (12, 16) reflects the radiation towards a second (16) of the two reflectors (12, 16). The reflectors (12, 16) have such spectral characteristics as to be capable of highly reflecting the radiation in a reflection range of wavelengths and absorbing the radiation in an absorption range of wavelengths, wherein the absorption range of wavelengths of the first reflector (12) substantially includes the absorption range of wavelengths of the second reflector (16).

Dielectric omnidirectional visible reflector.

Abstract: We demonstrate the fabrication of an all-dielectric omnidirectional mirror for visible frequencies. The dielectric reflector consists of a stack of 19 alternating layers of tin (IV) sulfide and silica. Using a combination of thermal evaporation (for tin sulfide) and thick electron-beam evaporation (for silica), we have achieved a refractive-index contrast of 2.6/1.46 , one of the highest refractive-index contrasts demonstrated in one-dimensional photonic bandgap systems designed for the visible frequency range. The tin sulfide-silica material system developed allowed the formation of a broadband visible reflector with an omnidirectional range greater than 10%. Possible applications of the system include efficient reflectors, high-frequency waveguides for communications and power delivery, and high- Q cavities.

Low sidelobe reflector antenna with shield

Abstract: A front feed reflector antenna with a dish reflector has a wave guide is coupled to a proximal end of the dish reflector, projecting into the dish reflector along a longitudinal axis. A dielectric block may be coupled to a distal end of the waveguide and a sub-reflector coupled to a distal end of the dielectric block. A shield is coupled to the periphery of the dish reflector. A subtended angle between the longitudinal axis and a line between the focal point and a distal periphery of the shield is 50 degrees or less.