GPS.zip_GPS 模拟_GPS模拟_gps自动导航pudn_gps路线模拟_卫星运行轨道

%% function [ ri,vi,d_0 ] = satelite( svnum,t,dsheft,dt) %satelite函数用于计算卫星的坐标、速度和伪距 %svnum为卫星编号，t为时间，dsheft为计算出的延时 %ri为卫星坐标，vi为卫星速度，d_0为真实距离 u=3.986005*10^14;%地球引力常数u w=(rem(svnum,4)-1)*pi/2;%近地点辐角w i=55/180*pi;%轨道倾角 Afs=fix(svnum/4)*pi/3;%升焦点赤经Ascending focal scab a=2.6609*10^7;%半长轴a tp=0;%时间基准tp M=sqrt(u/a^3)*(t-tp);%平近点角M e=0.01;%偏心率e E=M;%偏近点角E threshold=0.0001;%阈值 while(abs(E-M-e*sin(E))>threshold) E=M+e*sin(E); end Tay=2*atan(sqrt((1+e)/(1-e))*tan(E/2))/pi*180;%真近点角Trueanomaly Lz_Afs=[cos(Afs),sin(Afs),0;-sin(Afs),cos(Afs),0;0,0,1]; Lx_i=[1,0,0;0,cos(i),sin(i);0,-sin(i),cos(i)]; Lz_u=[cos(w+Tay/180*pi),sin(w+Tay/180*pi),0;-sin(w+Tay/180*pi),cos(w+Tay/180*pi),0;0,0,1]; F_oi=Lz_u*Lx_i*Lz_Afs;%坐标变换矩阵 p=a*(1-e*e);%半通径 ro_x=p/(1+e*cos(Tay/180*pi));%半径 ri=F_oi'*[ro_x,0,0]';%惯性系中位置坐标 vo_x=sqrt(u/p)*e*sin(Tay/180*pi); vo_y=sqrt(u/p)*(1+e*cos(Tay/180*pi)); vi=F_oi'*[vo_x,vo_y,0]';%惯性系中速度坐标 d_0=(dsheft+dt+unifrnd(-0.01,0.01))*3*10^8/(1023*8); end %%