www.gusucode.com > GPS仿真Matlab编程源码程序 > GPS仿真Matlab编程源码程序/signalgen.m
% *********** This program generate simulated GPS signal ***************** function signal=signalgen(svnum_sig,t1_sig,fs_sig,T1_sig,tdelay_sig,fc1,codeFreq) % svnum_sig:卫星序号 % t1_sig:采样开始时刻 % fs_sig:采样频率 % T1_sig:采样时间 % Tdelay_sig:信号延时时间 % fc1:载波频率 % 修改时间 2007年7月 % t1_sig=1.764e-3;fs_sig=1/5e6;T1_sig=1e-3,tdelay_sig,fc1 % t_sig_1=t1_sig:1/fs_sig:100e-3-1/fs_sig; % t_sig_2=100e-3:1/fs_sig:T1_sig; % t_sig=[t_sig_1,t_sig_2]; t_sig=t1_sig:1/fs_sig:t1_sig+T1_sig-1/fs_sig; Nt_sig=length(t_sig); sig1=exp(1i*2*pi*fc1*(t_sig-tdelay_sig)); %sig1=sin(2*pi*(1.254657e6+10)*(t_sig-tdelay_sig)+2*pi*51.46*(t_sig-tdelay_sig).^2+2*pi*17.15*(t_sig-tdelay_sig).^3); %sig1=sin(2*pi*1.254657e6.*(t_sig-tdelay_sig)+2*pi*100*(t_sig-50e-3)); % sig1_1=sin(2*pi*1.254657e6.*(t_sig_1-tdelay_sig)); % sig1_2=sin(2*pi*1.254657e6.*(t_sig_2-tdelay_sig)+2*pi*50*(t_sig_2-tdelay_sig-100e-3)); % sig1=[sig1_1,sig1_2]; %code2=digitizg(Nt,fs_sig,0,svnum_sig); codelay=codelaygen(Nt_sig,fs_sig,tdelay_sig,svnum_sig,t1_sig,codeFreq); signal=sig1.*codelay; %signal=signal;%+0.5*rand(1,Nt_sig); % N=20480; % NN=[1:N]; % NN1=NN*fs/20480; %S=fft(signal1,N); %figure,plot(NN1,abs(S)) %[b,a]=myfilter(fs); %signal=filter(b,a,signal1); %Fsignal2=fft(signal(1:N),N); %NN2=NN*fs/20480; %figure %plot(NN2,abs(Fsignal2))