Parabolic reflector

About: Parabolic reflector is a research topic. Over the lifetime, 3375 publications have been published within this topic receiving 30735 citations. The topic is also known as: paraboloid reflector & paraboloidal reflector.

A high-gain shared-aperture dual-band OAM antenna with parabolic reflector

Abstract: This paper presents a novel shared-aperture antenna array for producing orbital angular momentum (OAM) wave in both C- and X-bands with the center frequency of 5.8 and 10 GHz, respectively. To enhance the antenna directivity, a parabolic reflector is specially designed. The microstrip patch with parasitic element is employed to obtain broad bandwidth. The proposed antenna array consists of eight elements at each operating band. The C- and X-bands OAM arrays are combined in the same aperture to coincide the center of the dual-band arrays, which can be used as the feed of the parabolic reflector. The simulated results show that the proposed antenna can generate OAM beams with the maximum directivity of 20.1 dBi and 25.8 dBi at 5.8 and 10 GHz, respectively.

Reflection by a Concave Parabolic Mirror

Abstract: The diffraction of a plane electromagnetic wave axially incident on the concave side of a perfectly conducting parabolic reflector is solved exactly and in closed form in the frequency domain. The method of solution follows the technique originally proposed by Lamb in 1906, who, however, was unable to solve the problem addressed herein. The present solution is obtained by matching the left- and right-propagating fields at the focal line of the mirror.

Secondary and compound concentrators for parabolic-dish solar-thermal power systems

Abstract: A secondary optical element may be added to a parabolic dish solar concentrator to increase the geometric concentration ratio attainable at a given intercept factor. This secondary may be a Fresnel lens or a mirror, such as a compound elliptic concentrator or a hyperbolic trumpet. At a fixed intercept factor, higher overall geometric concentration may be obtainable with a long focal length primary and a suitable secondary matched to it. Use of a secondary to increase the geometric concentration ratio is more likely to e worthwhile if the receiver temperature is high and if errors in the primary are large. Folding the optical path with a secondary may reduce cost by locating the receiver and power conversion equipment closer to the ground and by eliminating the heavy structure needed to support this equipment at the primary focus. Promising folded-path configurations include the Ritchey-Chretien and perhaps some three element geometries. Folding the optical path may be most useful in systems that provide process heat.

Diamond Turning Of Parabolic Mirrors

Abstract: The manufacture and testing of a silver parabolic mirror cut directly with a diamond tool in a high precision numericallycontrolled lathe without subsequent optical figuring or polishing is described. The mirror is 6 in. in diameter with a 1.5 in. facal length, giving an f-number (ratio of focal length to beam diameter) of 0.25.