matlab雷达目标回波仿真

close all;clearvars;clc;
dbstop if error;
fid = fopen('tempiqa1.dat' , 'w+');
%% 模拟目标运动轨迹以及天线的基本参数
Pt = 10e-3;                                                           %发送信号功率w
Gt = 10;                                                                %天线增益 db
RCS =1.5;                                                              %取汽车的典型值,反射物的横截面积 平方米
ADCsamplef1 = 2e6;                                             %ADC采样率,主要是由于其中存在等待，为了保证时长的准确，此处chirp时长为8us ； 其中3us采样，5us等待
Framet = 50e-3;                                                    %扫频间隔为50ms
c = 3E8;
lambda = 3E8/77E9;
Aeff = lambda/2 * 0.04;                                         %接受天线的有效面积m^2
numRxAnnate = 4;                                                 %接收天线个数
d = lambda/2;
DistanceOfEachAnnate = [0 d 2*d 3*d]; %接收天线间距，以第一幅接收天线为0，以后每一段为两幅接收天线之间的间距;

% sction1 距离精度高，速度精度低段
SampleRsec1 = 16;
SampleVsec1 = 1024;
Bandsec1 = 20E6;
T1 = 1/ADCsamplef1*(SampleRsec1);
U1 = Bandsec1/T1;
DR1 = c/ 2 / Bandsec1;
DV1 = lambda/ 2 / T1 / SampleVsec1;
t1 = [0:SampleRsec1-1]/ADCsamplef1;
F1  = zeros(SampleVsec1,SampleRsec1);

% sction2 距离精度高，速度精度低段
ADCsamplef2 = 5.4e6;      %ADC采样率,主要是由于其中存在等待，为了保证时长的准确，此处chirp时长为47us ； 其中42us采样，5us等待
SampleRsec2 = 256;
SampleVsec2 = 128;
Bandsec2 = 800e6;
T2 = 1/ADCsamplef2*(SampleRsec2);
U2 = Bandsec2/T2;
DR2 = c/ 2 / Bandsec2;
DV2 = lambda/ 2 / T2 / SampleVsec2;
t2 = [0:SampleRsec2-1]/ADCsamplef2;
F2  = zeros(SampleVsec2,SampleRsec2);


% 目标回波信号
Frame = 300;                                                                             %至少要大于目标的帧数
TargetNumber = 3;                                                                    %回波目标个数
TargerFrameOrignalMatrix             = [Frame Frame Frame];        %如果目标出现帧数帧数超出，则目标被删除
TargerRangeOrignalMatrix             = [25 5 13];                           %m 距离
TargerVolectyOrignalMatrix           = [10  12 18];                        %m/s 速度为正表示远离 ， 速度为负表示靠近
TargerAccelerationOrignalMatrix    = [0 1 5];                               %m/s ^2
TargerRoadOrignalMatrix                = [2 0 0];                              %默认设定目标为直线运动，此处给出目标的车道位置，目标的角度信息由距离关系自动计算。其中0表示中间车道，左边为负右边为正
Mode = 0;

%%  信号模拟
%目标信号建模
Fk = [1 Framet;0 1];
Bk = [(Framet^2)/2  Framet]';
% 峰值点结构体定义
peakout.point_r = 0;peakout.point_v = 0;peakout.I1 = 0;peakout.Q1 = 0;
peakout.I2 = 0;peakout.Q2 = 0;peakout.I3 = 0;peakout.Q3 = 0;peakout.I4 = 0;peakout.Q4 = 0;
peaknum = 3072;

for i = 1 : TargetNumber        %目标个数循环
    
    Targetdeta = zeros(2 ,Frame );
    Targetdeta(:,1) = [TargerRangeOrignalMatrix(i) TargerVolectyOrignalMatrix(i)]';
    
    for j = 2 : TargerFrameOrignalMatrix(i)     %目标帧数循环
            
            Targetdeta(1:2,j) = Fk*Targetdeta(1:2,j-1) + Bk.*TargerAccelerationOrignalMatrix(i);
            Targetdeta(3,j) = asind(3.6*TargerRoadOrignalMatrix(i) / Targetdeta(1 , j));
            
            if (Targetdeta(1 , j) < 0)
                Targetdeta(1 , j) = 0;
                Targetdeta(2 , j) = 0;
            end
    end  
    
    Target(i).target =  Targetdeta();
    
    
    Target(i).Pr =  Pt*Gt./(4*pi.*Target(i).target(1,:).^2) .* RCS .* (1/4/pi./Target(i).target(1,:).^2.*Aeff);
    Target(i).sn = 1.3806505e-24 * 800e6 *  (32+(9/5)*25);
    
end

figure;
for i = 1 : TargetNumber
    plot(Target(i).target(1,:).*sind(Target(i).target(3,:)) , Target(i).target(1,:) ,   '*');
    hold on;
end

% 模拟回波时域信号
h1 = figure;
h2 = figure;
h3 = figure;

for cnt = 1 : Frame
       
     set(0,'CurrentFigure' , h3);
     for i = 1 : TargetNumber
         
         plot(cnt , Target(i).target(1,cnt) , 'o');
         hold on;       
         xlabel('帧数');
         ylabel('距离');
     end
    
   if(mod(cnt,2) == 0)
       
       Mode = 1;    %表示srsect1段 16*1024 20Mhz
       %  初始化天线存储内存
       for annatacnt = 1 : numRxAnnate
            srsec1(annatacnt).RX = zeros( SampleVsec1 , SampleRsec1);
       end
       
        for k = 1 :TargetNumber         
            
            for anrxcnt = 1 : numRxAnnate
       
                    dphi(anrxcnt) = 2*pi*DistanceOfEachAnnate(anrxcnt)*sind(Target(k).target(3,cnt)) / lambda;  
            end          
            
            %sec1 段回波数据模拟
            for i=1:SampleVsec1
                for j=1:SampleRsec1
                    R = Target(k).target(1,cnt) +Target(k).target(2,cnt)*(i-1)*T1 + Target(k).target(2,cnt)*t1(j);
                    f = 2*R/lambda + 2*U1*R*t1(j)/c;
                    w = 2*pi*f;
                    F1(i,j) = w + (rand(1)-0.5)/0.1/180*pi;
                end
            end

            for i=1:SampleVsec1
                for j=1:SampleRsec1
                     w = F1(i,j);
                     
                     for anncnt = 1 : numRxAnnate
                         
                          srsec1(anncnt).RX(i,j) =  srsec1(anncnt).RX(i,j) +sqrt( Target(k).Pr(cnt))* exp(sqrt(-1)*(w + dphi(anncnt))) + (rand(1) - 0.5)* sqrt( Target(k).sn);% *  %dphi(anncnt)
                     end
                    
                end
            end
        end
        srsecrx1 = srsec1(1).RX';
        srsecrx2 = srsec1(2).RX';
        srsecrx3 = srsec1(3).RX';
        srsecrx4 = srsec1(4).RX';
        
        black_manR = blackman(SampleRsec1);
        black_manV = blackman(SampleVsec1)';
        SR1 = srsecrx1.*repmat(black_manR,1,SampleVsec1);
        SR1 = SR1.*repmat(black_manV,SampleRsec1,1);
        fft_data1_1d = fft(SR1,SampleRsec1);
        fft_data1_1d = fft_data1_1d';
        fft_data1_2d = fft(fft_data1_1d,SampleVsec1);
        abs_data1 = abs(fft_data1_2d);
        
        %
        SR2 = srsecrx2.*repmat(black_manR,1,SampleVsec1);
        SR2 = SR2.*repmat(black_manV,SampleRsec1,1);
        fft_data2_1d = fft(SR2,SampleRsec2);
        fft_data2_1d = fft_data2_1d';
        fft_data2_2d = fft(fft_data2_1d,SampleVsec1);
        abs_data2 = abs(fft_data2_2d);
        
        %
        SR3 = srsecrx3.*repmat(black_manR,1,SampleVsec1);
        SR3 = SR3.*repmat(black_manV,SampleRsec1,1);
        fft_data3_1d = fft(SR3,SampleRsec1);
        fft_data3_1d = fft_data3_1d';
        fft_data3_2d = fft(fft_data3_1d,SampleVsec1);
        abs_data3 = abs(fft_data3_2d);
        %
        
        SR4 = srsecrx4.*repmat(black_manR,1,SampleVsec1);
        SR4 = SR4.*repmat(black_manV,SampleRsec1,1);
        fft_data4_1d = fft(SR4,SampleRsec1);
        fft_data4_1d = fft_data4_1d';
        fft_data4_2d = fft(fft_data4_1d,SampleVsec1);
        abs_data4 = abs(fft_data4_2d);
        
         set(0,'CurrentFigure' , h1);
        mesh(abs_data1);
        title( strcat('一维20Mhz 16点 ； dr = ' , num2str(DR1) ,'m ； 二维1024点； dv = ' , num2str(DV1) , 'm/s'));
        xlabel('距离维');
        ylabel('速度维');
   else
           
           Mode = 2;    %表示srsect1段 256*128 800Mhz 
            %  初始化天线存储内存
            for annatacnt = 1 : numRxAnnate
                
                srsec2(annatacnt).RX = zeros( SampleVsec2 , SampleRsec2);
            end
       
             %sec2 段回波数据模拟
             for k = 1 :TargetNumber   
                     
                    for anrxcnt = 1 : numRxAnnate

                            dphi(anrxcnt) = 2*pi*DistanceOfEachAnnate(anrxcnt)*sind(Target(k).target(3,cnt)) / lambda;   
                    end
                 
                    %sec2 段回波数据模拟
                    for i=1:SampleVsec2
                        for j=1:SampleRsec2
                            R = Target(k).target(1,cnt) +Target(k).target(2,cnt)*(i-1)*T2 + Target(k).target(2,cnt)*t2(j);
                            f = 2*R/lambda + 2*U2*R*t2(j)/c;
                            w = 2*pi*f;
                            F2(i,j) = w + (rand(1)-0.5)/0.1/180*pi;
                        end
                    end

                    for i=1:SampleVsec2
                        for j=1:SampleRsec2
                            w = F2(i,j);
                            
                             for anncnt = 1 : numRxAnnate
                                 
                                    srsec2(anncnt).RX(i,j) = srsec2(anncnt).RX(i,j) + sqrt( Target(k).Pr(cnt)) * exp(sqrt(-1)*(w + dphi(anncnt)))+ (rand(1) - 0.5)* sqrt( Target(k).sn);
                             end                                               
                        end
                    end             
             end
             
        srsecrx1 = srsec2(1).RX';
        srsecrx2 = srsec2(2).RX';
        srsecrx3 = srsec2(3).RX';
        srsecrx4 = srsec2(4).RX';
        
        black_manR = blackman(SampleRsec2);
        black_manV = blackman(SampleVsec2)';
        SR1 = srsecrx1.*repmat(black_manR,1,SampleVsec2);
        SR1 = SR1.*repmat(black_manV,SampleRsec2,1);
        fft_data1_1d = fft(SR1,SampleRsec2);
        fft_data1_1d = fft_data1_1d';
        fft_data1_2d = fft(fft_data1_1d,SampleVsec2);
        abs_data1 = abs(fft_data1_2d);
        
        %
        SR2 = srsecrx2.*repmat(black_manR,1,SampleVsec2);
        SR2 = SR2.*repmat(black_manV,SampleRsec2,1);
        fft_data2_1d = fft(SR2,SampleRsec2);
        fft_data2_1d = fft_data2_1d';
        fft_data2_2d = fft(fft_data2_1d,SampleVsec2);
        abs_data2 = abs(fft_data2_2d);
        
        %
        SR3 = srsecrx3.*repmat(black_manR,1,SampleVsec2);
        SR3 = SR3.*repmat(black_manV,SampleRsec2,1);
        fft_data3_1d = fft(SR3,SampleRsec2);
        fft_data3_1d = fft_data3_1d';
        fft_data3_2d = fft(fft_data3_1d,SampleVsec2);
        abs_data3 = abs(fft_data3_2d);
        %
        
        SR4 = srsecrx4.*repmat(black_manR,1,SampleVsec2);
        SR4 = SR4.*repmat(black_manV,SampleRsec2,1);
        fft_data4_1d = fft(SR4,SampleRsec2);
        fft_data4_1d = fft_data4_1d';
        fft_data4_2d = fft(fft_data4_1d,SampleVsec2);
        abs_data4 = abs(fft_data4_2d);
        
        set(0,'CurrentFigure' , h2);
        mesh(abs_data1);
        title( strcat('一维800Mhz 256点 ； dr = ' , num2str(DR2) ,'m ； 二维128点； dv =  ' , num2str(DV2) , 'm/s'));
        xlabel('距离维');
        ylabel('速度维');
   end
   
   %%  找峰值点，并把峰值点传出来
   avemeans = mean(abs_data1)*1.5;
   avemeans = repmat(avemeans , size(abs_data1 , 1) , 1);
   peak_matrix = imregionalmax(abs_data1);
   peak_matrix = peak_matrix .* abs_data1;
   peak_matrix(peak_matrix < avemeans) = 0;
   peak_matrix = peak_matrix * 1e6;
   g_menxian = avemeans(1,:)*1e6;
   [point_r point_v]= find(peak_matrix > 0);
   
   len = length(point_r);
   if len > 3072
       len = 3072;
   end
   
   for peakcnt = 1 : 3072
       peakout(peakcnt).point_r = 0; peakout(peakcnt).point_v=0;
       peakout(peakcnt).I1 = 0;peakout(peakcnt).Q1 = 0;
       peakout(peakcnt).I2 = 0; peakout(peakcnt).Q2 = 0;
       peakout(peakcnt).I3 = 0; peakout(peakcnt).Q3 = 0;
       peakout(peakcnt).I4 = 0; peakout(peakcnt).Q4 = 0;
   end
   %peak_matrix为峰值点位置 ； g_menxian为门限值，之后组帧数据传输出去
   for peakcnt = 1 : length(point_r)
       
       peakout(peakcnt).point_r = point_r(peakcnt);
       peakout(peakcnt).point_v = point_v(peakcnt);
       peakout(peakcnt).I1 = real(fft_data1_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).Q1 = imag(fft_data1_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).I2 = real(fft_data2_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).Q2 = imag(fft_data2_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).I3 = real(fft_data3_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).Q3 = imag(fft_data3_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).I4 = real(fft_data4_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
       peakout(peakcnt).Q4 = imag(fft_data4_2d( point_r(peakcnt) , point_v(peakcnt))) *  1e6;
   end
   
   for peakcnt = 1 : 3072
       
       fwrite(fid, peakout(peakcnt).point_r , 'uint16');
       fwrite(fid, peakout(peakcnt).point_v , 'uint16');
       fwrite(fid, int16(peakout(peakcnt).I1) , 'int16');
       fwrite(fid, int16(peakout(peakcnt).Q1) , 'int16');
       fwrite(fid, int16(peakout(peakcnt).I2) , 'int16');
       fwrite(fid, int16(peakout(peakcnt).Q2) , 'int16');
       fwrite(fid, int16(peakout(peakcnt).I3) , 'int16');
       fwrite(fid, int16(peakout(peakcnt).Q3) , 'int16'); 
       fwrite(fid, int16(peakout(peakcnt).I4) , 'int16');
       fwrite(fid, int16(peakout(peakcnt).Q4) , 'int16');     
       
   end
   
   pause(0.01);
end

fclose(fid);