Analysis of shaped offset-fed reflector satellite antennas for producing a contoured beam to cover the Taiwan region

• Main Authors: Sheng-lung Chen, 陳盛龍
• Other Authors: Wuey-Ru Chuang
• Format: Others
• Language: en_US
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/84867408880653591448

碩士 === 國立成功大學 === 電機工程研究所 === 82 === In order to provide the maximum radiation power over specified coverage areas, communication satellite antenna are often required to produce contoured radiation patterns to fit the desired coverage regions. This has most usually been achieved by using array-fed parabolic rreflector antennas, with beam forming networks (BFN) to adjust the amplitude and phase of each feed, to synthesize desired contoured patterns. However, the complexity of the BFN will increase the RF loss and the weight of the satellite platform. This thesis will investigate the use of a single shaped parabolic reflector antenna and a single feed for producing a contoured beam to cover the Taiwan region. First, the characteristics and parameters of the parabolic reflector antenna will be studied. The geometrical optics (GO) and physical opticals (PO) method are used to caculate the far field and antenna gain. The aperture phase distribution is optimized to synthesize the far-field contoured pattern with the GO method. The reflector surface is then determined from the aperture phase distribution. The radiation performance of the shaped surface is then checked by applying the PO method. Finally, the analysis and calculation of a shaped offset-fed parabolic reflector satellite antenna is performed to produce a contoured beam to cover the Taiwan region.