... Beamwidth defines the field of view 2. ... Large diameter = high sensitivity = small beamwidth 3 To calculate the radiation pattern : Compute field in focal plane from surface currents excited by the incoming wavefront. ... Feed Legs (quadrupod on the AT antennas) plane wave shadows (radiation which does not reach the main reflector) spherical wave shadows (radiation blocked between the main and the sub-reflector) 6 Surface Errors н Ruze formula Let be the rms surface error. ...
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Ссылки http://www.atnf.csiro.au/whats_on/workshops/synthesis2001/material/antennas.pdf -- 1072.6 Кб -- 15.01.2002 Похожие документы
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... Twenty-Six Year Monitoring of Water Masers IAU Symposium 242, Alice Springs 1 Contents of the work A sample of H2O maser emission sources has been observed since 1980. ... Rudnitskij et al. ... Twenty-Six Year Monitoring of Water Masers IAU Symposium 242, Alice Springs 4 Maser in a protoplanetary disc (S255) Flux density, Jy S255: H2O line profile 5 February 2002 Radial velocity, LSR, km/s Rudnitskij et al. ... Twenty-Six Year Monitoring of Water Masers IAU Symposium 242, Alice Springs 12 ...
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Ссылки http://www.atnf.csiro.au/research/masermeeting/web_papers/523_Rudnitskij.pdf -- 481.0 Кб -- 26.04.2007 Похожие документы