可以仿真的锁相环的matlab代码.doc

%频偏：-60Hz%相偏：在02*pi内随机分布 %程序及结果如下：clear all;close all;%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if PLL_Mode = 1I_Data=ones(Simulation_Length,1);Q_Data=I_Data;else if PLL_Mode = 2I_Data=randint(Simulation_Length,1)*2-1;Q_Data=zeros(Simulation_Length,1);else I_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/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(Simulation_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;for i=2:Simulation_LengthSignal_PLL(i)=Signal_Channel(i)*exp(-j*mod(NCO_Phase(i-1),2*pi);I_PLL(i)=real(Signal_PLL(i);Q_PLL(i)=imag(Signal_PLL(i);if PLL_Mode = 1Discriminator_Out(i)=atan2(Q_PLL(i),I_PLL(i);else if PLL_Mode = 2Discriminator_Out(i)=sign(I_PLL(i)*Q_PLL(i)/abs(Signal_PLL(i);elseDiscriminator_Out(i)=(sign(I_PLL(i)*Q_PLL(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%画图显示结果figuresubplot(2,2,1)plot(-PLL_Freq_Part(2:Simulation_Length)*Freq_Sample);grid on;title(锁相环频率响应曲线);axis(1 Simulation_Length -100 100);subplot(2,2,2)plot(PLL_Phase_Part(2:Simulation_Length)*180/pi);title(锁相环相位响应曲线);axis(1 Simulation_Length -2 2);grid on;%设定显示范围Show_D=300; %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:Show_U),*);title(进入锁相环的数据星座图);axis(-2 2 -2 2);grid on;hold on;subplot(2,2,3)plot(Signal_PLL(Show_D:Show_U),r*);grid on;subplot(2,2,4)plot(Signal_PLL(Show_D:Show_U),r*);title(锁相环锁定及稳定后的数据星座图);axis(-2 2 -2 2);grid on; figure%设定显示范围Show_D=300; %起始位置Show_U=350; %终止位置Show_Length=Show_U-Show_D;subplot(2,2,1)plot(I_Data(Show_D:Show_U);grid on;title(I路信息数据);axis(1 Show_Length -2 2);subplot(2,2,2)plot(Q_Data(Show_D:Show_U);grid on;title(Q路信息数据);axis(1 Show_Length -2 2);subplot(2,2,3)plot(I_PLL(Show_D:Show_U);grid on;title(锁相环