matlab计算峰值旁瓣比和积分旁瓣比

%%%%%%%%%%%%%%%%%评估指标为点目标距离向和方位向峰值坐标、峰值旁瓣比、一维积分旁瓣比、二维积分旁瓣比、剖面图%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%处理矩阵列为距离向%%%%%%%%%%%%%%%%% %%%%%一维积分旁瓣比定义第一零点以外为旁瓣，二维积分旁瓣比主瓣近似矩形计算%%%%%%%%%%%%%%%%% %%%%%%%%%%%%%%%%%%%%% clc; clear all; Nr=512; Na=2048; fs=1e9; v0=6887.683; PRF=44887.73; c=3e8; %%%%%%%%%%%%%%%%读取数据%%%%%%%%%%%%%%%%%%%% %回波数据 echo=[]; shu=[]; M=[]; guodu=zeros(1,Nr); fid=fopen('评估结果.SAR_Result.dat','rb'); for i=1:Na M=fread(fid,Nr*2,'float'); for m=1:Nr guodu(1,m)=M(2*m-1)+M(2*m)*1j; end echo(i,:)=guodu; end fclose(fid); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%二维插值处理，D2为二维插值倍数%%%%%%%%%%%%%%%%%% echo=echo';%%每列有512个点，列为距离向 Max=max(max(abs(echo))); %最大值 [X,Y]=find(abs(echo)==Max);%峰值坐标 DArea=echo(X-128:X+128,Y-128:Y+128); %%取257*257区域 E1=fftshift(fft(DArea),1);%先距离向 E2=fftshift(fft(E1.'),1); D2=8;%二维D2倍插值 A3=[zeros(257,floor(257*(D2-1)/2)) E2 zeros(257,(D2-1)*257-floor(257*(D2-1)/2))]; A4=[zeros(D2*257,floor(257*(D2-1)/2)) A3.' zeros(D2*257,(D2-1)*257-floor(257*(D2-1)/2))]; A4=A4.'; A5=ifft(fftshift(A4,1)); A6=ifft(fftshift(A5.',1));%%%转回时域； %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%一维维插值处理，D1为插值倍数%%%%%%%%%%%%%%%%%% Max_one=max(max(abs(A6))); %最大值 [i,j]=find(abs(A6)==Max_one);%最大值所在行列 A=A6(i-128:i+128,j);%抽取列,距离向 B=A6(i,j-128:j+128);%抽取行，方位向 A1=fftshift(fft(A.')); B1=fftshift(fft(B)); D1=128;%插值倍数 R1=[zeros(1,floor(length(A1)*(D1-1)/2)) A1 zeros(1,floor(length(A1)*(D1-1)/2))]; B2=[zeros(1,floor(length(B1)*(D1-1)/2)) B1 zeros(1,floor(length(B1)*(D1-1)/2))]; R2=abs(ifft(fftshift(R1)));%%距离向插值后到时域 A2=abs(ifft(fftshift(B2)));%%方位向插值后到时域 r2=20*log10(R2/max(R2));%%距离向归一化 a2=20*log10(A2/max(A2));%%方位向归一化 %%%%%%%%%%%距离向分辨率%%%%%%%%%%%%%%%%%%%%%% [max_r,POS_r]=max(r2); r3=POS_r; %%%%%%%%%%%%%%左边3DB点%%%%%%%%%%%% while(r2(r3)>-3) r3=r3-1; end; rWidth_3db1=r3; %%%%%%%%%%%%%找左边第一零点%%%%%%%%%%%%%% for r4=rWidth_3db1:-1:1 if R2(r4)<R2(r4-1) break end end zero_left=r4; %%%%%%%%%%%%%找左边第一旁瓣值%%%%%%%%%%%%%% for r5=zero_left-1:-1:1 if R2(r5)>R2(r5-1) break end end %%%%%%%%%%%%%左边旁瓣能量%%%%%%%%%%%%%% r_Sum_sidelobe1=0; for rs1=1:zero_left-1 r_Sum_sidelobe1 = r_Sum_sidelobe1 +R2(rs1) * R2(rs1);%%%左边旁瓣求和 end %%%%%%%%%%%%%%右边3DB点%%%%%%%%%%%% r3=POS_r+1; while(r2(r3)>-3) r3=r3+1; end; rWidth_3db2=r3; %%%%%%%%%%%%%找右边第一零点%%%%%%%%%%%%%% for r6=rWidth_3db2:length(r2) if R2(r6)<R2(r6+1) break end end zero_right=r6; %%%%%%%%%%%%%找右边第一旁瓣值%%%%%%%%%%%%%% for r7=zero_right+1:length(r2) if R2(r7)>R2(r7+1) break end end %%%%%%%%%%%%%主瓣能量%%%%%%%%%%%%%% r_Sum_mainlobe=0; for r8=zero_left:zero_right r_Sum_mainlobe= r_Sum_mainlobe+R2(r8)*R2(r8); end %%%%%%%%%%%%%右边旁瓣能量%%%%%%%%%%%%%% r_Sum_sidelobe =r_Sum_sidelobe1 ; for rs2=zero_right+1:length(r2) r_Sum_sidelobe=r_Sum_sidelobe +R2(rs2)*R2(rs2); end %%%%%%%%%%%%找第一旁瓣较大值%%%%%%%%%%%%%% rMax_sidelobe=max(R2(r5),R2(r7)); rMax_mainlobe=max(R2); %%%%%%%%%%%%%距离向指标计算%%%%%%%%%%%%% figure(1);plot(r2);title('距离向切面'); ISLRr=10*log10(r_Sum_sidelobe/r_Sum_mainlobe);%%%距离向积分旁瓣比 PSLRr=20*log10(rMax_sidelobe/rMax_mainlobe);;%%%距离向峰值旁瓣比 r_3db=rWidth_3db2-rWidth_3db1+2;%3db 带宽 fenbianlv_r=c*r_3db/(2*fs*D1*D2); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%%%%%%%%%方位向分辨率%%%%%%%%%%%%%%%%%%%%%% [max_a,POS_a]=max(a2); a3=POS_a; a_Sum_sidelobe1=0; %%%%%%%%%%%%%%左边3DB点%%%%%%%%%%%% while(a2(a3)>-3) a3=a3-1; end; aWidth_3db1=a3; %%%%%%%%%%%%%找左边第一零点%%%%%%%%%%%%%% for a4=aWidth_3db1:-1:1 if A2(a4)<A2(a4-1) break end end a_zero_left=a4; %%%%%%%%%%%%%找左边第一旁瓣值%%%%%%%%%%%%%% for a5=a_zero_left-1:-1:1 if A2(a5)>A2(a5-1) break end end %%%%%%%%%%%%%左边旁瓣能量%%%%%%%%%%%%%% for as1=1:a_zero_left-1 a_Sum_sidelobe1 = a_Sum_sidelobe1 +A2(as1) * A2(as1);%%%左边旁瓣求和 end %%%%%%%%%%%%%%右边3DB点%%%%%%%%%%%% a3=POS_a+1; while(a2(a3)>-3) a3=a3+1; end; aWidth_3db2=a3; %%%%%%%%%%%%%找右边第一零点%%%%%%%%%%%%%% for a6=aWidth_3db2:length(a2) if A2(a6)<A2(a6+1) break end end a_zero_right=a6; %%%%%%%%%%%%%找右边第一旁瓣值%%%%%%%%%%%%%% for a7=a_zero_right+1:length(a2) if A2(a7)>A2(a7+1) break end end %%%%%%%%%%%%%主瓣能量%%%%%%%%%%%%%% a_Sum_mainlobe=0; for a8=a_zero_left:a_zero_right a_Sum_mainlobe=a_Sum_mainlobe+A2(a8)*A2(a8); end %%%%%%%%%%%%%右边旁瓣能量%%%%%%%%%%%%%% a_Sum_sidelobe =a_Sum_sidelobe1 ; for as2=a_zero_right+1:length(a2) a_Sum_sidelobe=a_Sum_sidelobe +A2(as2)*A2(as2); end %%%%%%%%%%%%找第一旁瓣较大值%%%%%%%%%%%%%% aMax_sidelobe=max(A2(a5),A2(a7)); aMax_mainlobe=max(A2); %%%%%%%%%%%%%方位向指标计算%%%%%%%%%%%%% figure(2);plot(a2);title('方位向切面'); a_3db=aWidth_3db2-aWidth_3db1+2;%3db 带宽 fenbianlv_a=v0*a_3db/(PRF*D1*D2); ISLRa=10*log10(a_Sum_sidelobe/a_Sum_mainlobe);%%%距离向积分旁瓣比 PSLRa=20*log10(aMax_sidelobe/aMax_mainlobe);%%%距离向峰值旁瓣比 %%%%%%%%%%%%二维积分旁瓣比%%%%%%%%%%%%% %%%%%%%%%%%主瓣近似矩形计算%%%%%%%%%%%%% %%%%%%%%%%%%%计算总能量%%%%%%%%%%%%% totallobe=0; A7=abs(A6); for m=1:length(A7) for n=1:length(A7) totallobe=totallobe+A7(m,n)*A7(m,n); end end %%%%%%%%%%%%%确定主瓣%%%%%%%%%%%%% two_r_zero=floor((zero_right-zero_left)/D1); two_a_zero=floor((a_zero_right-a_zero_left)/D1); %%%%%%%%%%%%%计算主瓣能量%%%%%%%%%%%%% mainlobe=0; for t1=i-floor(two_a_zero/2):i+floor(two_a_zero/2) for t2=j-floor(two_r_zero/2):j+floor(two_r_zero/2) mainlobe=mainlobe+A7(t1,t2)*A7(t1,t2); end end ISLR=10*log10(( totallobe-mainlobe)/mainlobe); %%%%%%%%%%%%%X，Y为峰值坐标%%%%%%%%%%%%%