摘要
中国区域卫星定位系统(CAPS)是卫星导航通信一体化的系统。当利用CAPS微小卫星终端系统进行卫星通信时,所用的天线口径极小,增益低,终端的有效全向辐射功率EIRPe较小,整个通信链路的余量较小。虽然C波段的降雨衰减远没有Ku波段大,但是相对于微小卫星终端的整个卫星通信链路来说,降雨带来的信号衰减、地球站接收天线G/T值的变化以及对卫星通信上、下行链路载噪比的影响也是不可忽视的。文章对这些影响进行了分析,并利用ITU-R给出的降雨衰减预报模式,给出了C波段的降雨衰减的计算方法及结果,并且分析了降雨对CAPS微小卫星通信系统的整个链路余量的影响。
The Chinese Area Positioning System （CAPS） is based on communication satellites with integrated capability. In the CAPS Micro-MSAT satellite communication system, the earth terminal transmitting antenna is omnidirectional, with the transmitting gain of only 0~3dBi, thus leading to the results that the effective isotropic radiated power （EIRP） of the earth terminal is so low that this communication system is an uplink power limited system. Although the rain attenuation is far less than that of Ku band, the signal attenuation, the variation of the receiving antenna G/T and the influence to the uplink and downlink by rain could＇ t be neglected. This paper analyzes this influence, and provides the calculating method and results about the rain attenuation of C band according to the ITU-R rain attenuation prediction model recommendations, and the influence on the CAPS Micro-MSAT system link margin.
出处
《通信技术》
2009年第6期8-10,共3页
Communications Technology
基金
国家重点基础研究发展计划(973计划)资助(编号:2007CB815500)
