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A concept/technique is described for reducing the effects of multipath contamination of the main beam, by using antenna phase center diversity. Results of a concept validation test are given.
The frequency selective surfaces (FSS) find application in many diverse area, such as polarizers, antenna reflectors due to their resonance properties. In the case of infinite FSS are used: mode — matching method [1] and spectral — domain approach [2],[3]. For the infinite 20 periodical arrays is convenient to use the Floquet harmonics for the field representation in the free space.
A mechanically-scanned offset reflector with a multiple feed array is proposed as a feasible configuration for a radiometric antenna. The antenna is designed to operate over six different frequency bands, ranging from 6.80 GHz to 90.0 GHz, and is optimized to simultaneously satisfy the requirements on beam footprint overlap, sidelobe and cross-polar levels. Computed electrical performance is presented...
Shaped beam reflector antennas are commonly used in satellite communications applications where performance considerations other than high gain may be of importance. For large antennas, the feed and reflector are usually considered to be uncoupled and are analysed separately [1]. The analysis of the feed requires a more exact solution technique with an integral equation formulation or mode expansion...
A model for determining the antenna phase center and its movement due to multipath reception is defined and analyzed. It is shown that for the azimuth antenna in the Microwave Landing System (MLS) the phase center is susceptible to interaction of the direct signal and the indirect signals reflected by the ground.
Reflector configurations suitable for a multibeam EHF satellite communication receive antenna are reviewed in this paper. Four different antenna systems have been studied and their relative performances are compared. Computer simulations have been performed to analyze the co-polar and cross-polar gain contours of the antennas and the results are discussed.
A JPL Fortran program for designing the main reflector and the subreflector of a Galindo-Williams system with a constant intensity over the aperture of the main reflector was modified for use on our computer system. Geometrical Optics and conservation of energy are the basic laws used for designing this type of surface. The basic computation is a numerical solution of three simultaneous differential...
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