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A common but difficult antenna requirement for medium earth orbit (MEO) communication satellite is the generation of simultaneous multiple beams over a wide coverage area. The beams should be highly overlapped in order to provide high coverage gain but yet with sufficient decay in the sidelobes to yield the necessary isolation between every other beam. An efficient antenna solution to this problem...
Multiple beam antennas (MBA) for satellite communications usually provide a contiguous coverage over a specified field-of-view by using high gain overlapping spot beams. The common design objective for all MBAs is to maximize the minimum gain within the coverage region. If the MBA has uniform beams arranged in a hexagonal grid, the minimum gain occurs at the triple beam cross-over and the gain variation...
This paper describes parametric relationships that affect the design of high gain multibeam antennas, discusses tradeoffs, and presents optimized performance of two candidate antennas for wide-angle coverage Advanced Satcom: an aperiodic array with suppressed grating lobes and reduced number of elements, and a side-fed offset Cassegrain system with low scan loss. Given basic performance requirements...
Shaped reflector antennas are capable of producing desired coverage contours on earth by using a single horn thereby avoiding the need for complicated feed arrays and associated beamforming networks (BFNs). The advantages of shaped reflector technology for SATCOM antennas are lower cost, reduced mass and shorter delivery schedule. Development results of a dual-gridded shaped reflector designed for...
Boyle Cheng, PhD, is a faculty assistant professor in the Department of Neurosurgery at Drexel University — Allegheny General Hospital. He is the Director of the Neurosurgery Spine and Biomechanics Laboratory for the newly established Neuroscience Institute. Dr. Cheng joined the System from the University of Pittsburgh, where he served as assistant professor for the Departments of Neurological Surgery...
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