基于EPFD的NGSO下行链路对GSO地球站的干扰分析方法

Interference Analysis Method of NGSO Downlink to GSO Earth Station Based on EPFD

非静止轨道(NG SO)与静止轨道(G SO)卫星系统在部分频段同频共存,《无线电规则》中规定在卫星固定业务(FS S)、卫星广播业务(B S S)划分频段内NG SO系统须满足规定的等效功率通量密度(EPFD)限值以保护G SO系统。文章阐述了EPFD的定义,指出EPFDdown是两系统共存最具有制约性的参数,梳理了根据国际电信联盟无线电通信部门(ITU-R)建议书S.1503计算EPFDdown的流程,包括生成功率通量密度(PFD)包络、确定计算内容,定义最差几何形状(WCG)和决策,最后给出使用Transf inite软件进行NGSO下行链路对GSO地球站的干扰分析流程示例。

NGSO and GSO satellite system coexist in some frequency bands.The Radio Regulation stipulates that the NGSO system must meet the specified EPFD limit to protect GSO system in FSS and BSS frequency band.This paper expounds the definition of EPFD and points out that EPFDdown is the most restrictive parameter in the frequency sharing between two systems;The process of calculating EPFDdown with ITU-R Recommendation S.1503 is sorted out,including generating PFD mask,determining calculation content,defining the Worst Case Geometry(WCG)and decision-making;An interference analysis case of NGSO downlink to GSO earth station using Transfinite software is given.