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1、%频偏:-60Hz%相偏:在0--2*pi内随机分布%程序及结果如下:clearall;closeall;%定义锁相环的工作模式:单载波为“1”、BPSK调制为“2”、QPSK调制为“3”PLL_Mode=3;%仿真数据长度Simulation_Length=1000;%基带信号ifPLL_Mode==1I_Data=ones(Simulation_Length,1);Q_Data=I_Data;elseifPLL_Mode==2I_Data=randint(Simulation_Length,1)*2-1;Q_Data=zeros(Sim
2、ulation_Length,1);elseI_Data=randint(Simulation_Length,1)*2-1;Q_Data=randint(Simulation_Length,1)*2-1;endendSignal_Source=I_Data+j*Q_Data;%载波信号Freq_Sample=2400;%采样率,HzDelta_Freq=-60;%频偏,HzTime_Sample=1/Freq_Sample;Delta_Phase=rand(1)*2*pi;%随机初相,RadCarrier=exp(j*(Delta_Freq
3、/Freq_Sample*(1:Simulation_Length)+Delta_Phase));%调制处理Signal_Channel=Signal_Source.*Carrier';%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%以下为锁相环处理过程%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%参数清零Signal_PLL=zeros(Simulation_Length,1);NCO_Phase=zeros(Simula
4、tion_Length,1);Discriminator_Out=zeros(Simulation_Length,1);Freq_Control=zeros(Simulation_Length,1);PLL_Phase_Part=zeros(Simulation_Length,1);PLL_Freq_Part=zeros(Simulation_Length,1);%环路处理C1=0.22013;C2=0.0024722;fori=2:Simulation_LengthSignal_PLL(i)=Signal_Channel(i)*exp(-
5、j*mod(NCO_Phase(i-1),2*pi));I_PLL(i)=real(Signal_PLL(i));Q_PLL(i)=imag(Signal_PLL(i));ifPLL_Mode==1Discriminator_Out(i)=atan2(Q_PLL(i),I_PLL(i));elseifPLL_Mode==2Discriminator_Out(i)=sign(I_PLL(i))*Q_PLL(i)/abs(Signal_PLL(i));elseDiscriminator_Out(i)=(sign(I_PLL(i))*Q_PLL(
6、i)-sign(Q_PLL(i))*I_PLL(i)).../(sqrt(2)*abs(Signal_PLL(i)));endendPLL_Phase_Part(i)=Discriminator_Out(i)*C1;Freq_Control(i)=PLL_Phase_Part(i)+PLL_Freq_Part(i-1);PLL_Freq_Part(i)=Discriminator_Out(i)*C2+PLL_Freq_Part(i-1);NCO_Phase(i)=NCO_Phase(i-1)+Freq_Control(i);end%画图显示
7、结果figuresubplot(2,2,1)plot(-PLL_Freq_Part(2:Simulation_Length)*Freq_Sample);gridon;title('锁相环频率响应曲线');axis([1Simulation_Length-100100]);subplot(2,2,2)plot(PLL_Phase_Part(2:Simulation_Length)*180/pi);title('锁相环相位响应曲线');axis([1Simulation_Length-22]);gridon;%设定显示范围Show_D=300;
8、%起始位置Show_U=900;%终止位置Show_Length=Show_U-Show_D;subplot(2,2,3)plot(Signal_Channel(Show_D:S