Topic
Cassegrain antenna
About: Cassegrain antenna is a research topic. Over the lifetime, 3207 publications have been published within this topic receiving 28278 citations.
Papers published on a yearly basis
Papers
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TL;DR: In this article, the sum and difference patterns can be obtained by in-phase and out-of-phase excitations of the two coaxial ports of a crescent-shaped radiating element fed from two sides at an angle close to 90°.
Abstract: A novel ultrawideband pattern diversity antenna, with sum and difference radiation patterns used in monopulse tracking, is proposed. To achieve pattern diversity, a crescent-shaped radiating element is fed from two sides at an angle close to 90°, by two coaxial feeds. The ground is a corner-shaped cavity. The sum and difference patterns can be obtained by in-phase and out-of-phase excitations of the two coaxial ports. A single-element antenna is first studied to show the operating principle of the design. A modified design with two elements is then proposed and studied through simulations and measurements of a fabricated prototype, showing excellent radiation characteristics over a large frequency bandwidth. The application of this antenna as a reflector feed is then studied. It is shown that the antenna can theoretically feed a prime focus reflector with 60% (for the sum pattern) efficiency over a 48% fractional bandwidth (5.5–9 GHz), with a maximum efficiency of 75%. The antenna is compact (5 × 4.1 × 2 cm3) and has low cost and simple fabrication. To the best of authors’ knowledge, this is the first attempt to feed a reflector with this class of antennas.
11 citations
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01 Mar 2010TL;DR: In this paper, a simple planar Yagi-Uda antenna with a single director and a concave parabolic reflector on a thin dielectric substrate is proposed, which can achieve the high directivity of 9.0 dBi, front-to-back ratio of 14.5 dB, cross-polarization level of −38.7 dB, bandwidth of 6.0%, and the radiation efficiency of 85.1%.
Abstract: A simple planar Yagi-Uda antenna with a single director and a concave parabolic reflector on a thin dielectric substrate is proposed. Through the innovative design, the simple Yagi-Uda antenna can achieve the high directivity of 9.0 dBi, front-to-back ratio of 14.5 dB, cross-polarization level of −38.7 dB, bandwidth of 6.0%, and the radiation efficiency of 85.1%, i.e., better than −1 dBi in terms of the 3D average gain. This proposed antenna is especially suitable for the mobile devices with GPS functions.
11 citations
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TL;DR: In this paper, the authors derived a formula to evaluate the relative influence of subreflector and main reflector surface errors on overall tolerance loss for a dual-reflector antenna.
Abstract: A formula is derived to evaluate the relative influence of subreflector and main reflector surface errors on overall tolerance loss for a dual-reflector antenna. Comparisons are made with the results of random-number simulation of surface errors in a Gregorian system.
11 citations
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17 May 2015TL;DR: This paper reviews some recent development in millimetre-wave smart antennas for satellite communications as well as show some results of case studies on this topic.
Abstract: This paper reviews some recent development in millimetre-wave smart antennas for satellite communications as well as show some results of case studies on this topic. Two case studies are presented, including one Ka-band fully integrated active reflectarray with wide-angle beam steering capabilities for SatCom on the move, and one beam-switching array-fed reflector antenna for advanced satellite communications. Design concept of the antenna elements and arrays in each case studies are explained and discussed.
11 citations
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TL;DR: An improved 3-D ray tracing method based on the vector theory of reflection is used to simulate spatial rays transmitting through the antenna system, which will provide a reference for improving the transmission efficiency of long-range communication systems.
Abstract: A novel optical antenna with an off-axis confocal parabolic rotating surfaces configuration is designed for achieving maximum transmission efficiency. An improved 3-D ray tracing method based on the vector theory of reflection is used to simulate spatial rays transmitting through the antenna system. Aberrations and the spatial divergence angles of the output beam, which are caused by on-axial defocusing and off-axial defocusing between the primary reflector and secondary reflector, are visualized and effects on receiver efficiency of the antenna system are analyzed in detail. This work will provide a reference for improving the transmission efficiency of long-range communication systems.
11 citations