資源簡介
點(diǎn)目標(biāo)質(zhì)量評估,一維積分旁瓣比、峰值旁瓣比
代碼片段和文件信息
%%%%%%%%%%%%%%%%%評估指標(biāo)為點(diǎn)目標(biāo)距離向和方位向峰值坐標(biāo)、峰值旁瓣比、一維積分旁瓣比、二維積分旁瓣比、剖面圖%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%處理矩陣列為距離向%%%%%%%%%%%%%%%%%
%%%%%一維積分旁瓣比定義第一零點(diǎn)以外為旁瓣,二維積分旁瓣比主瓣近似矩形計(jì)算%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%
clc;
clear?all;
Nr=512;
Na=2048;
fs=1e9;
v0=6887.683;
PRF=44887.73;
c=3e8;
%%%%%%%%%%%%%%%%讀取數(shù)據(jù)%%%%%%%%%%%%%%%%%%%%
%回波數(shù)據(jù)
echo=[];
shu=[];
M=[];
guodu=zeros(1Nr);
fid=fopen(‘評估結(jié)果.SAR_Result.dat‘‘rb‘);
for?i=1:Na
???M=fread(fidNr*2‘float‘);
???for?m=1:Nr
???????guodu(1m)=M(2*m-1)+M(2*m)*1j;
???end
???echo(i:)=guodu;
end
fclose(fid);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%二維插值處理,D2為二維插值倍數(shù)%%%%%%%%%%%%%%%%%%
echo=echo‘;%%每列有512個點(diǎn),列為距離向
Max=max(max(abs(echo)));??%最大值
[XY]=find(abs(echo)==Max);%峰值坐標(biāo)
?DArea=echo(X-128:X+128Y-128:Y+128);?%%取257*257區(qū)域
?E1=fftshift(fft(DArea)1);%先距離向
?E2=fftshift(fft(E1.‘)1);
?D2=8;%二維D2倍插值
?A3=[zeros(257floor(257*(D2-1)/2))?E2?zeros(257(D2-1)*257-floor(257*(D2-1)/2))];
?A4=[zeros(D2*257floor(257*(D2-1)/2))?A3.‘?zeros(D2*257(D2-1)*257-floor(257*(D2-1)/2))];
?A4=A4.‘;
?A5=ifft(fftshift(A41));
?A6=ifft(fftshift(A5.‘1));%%%轉(zhuǎn)回時域;
?%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%一維維插值處理,D1為插值倍數(shù)%%%%%%%%%%%%%%%%%%
?Max_one=max(max(abs(A6)));??%最大值
[ij]=find(abs(A6)==Max_one);%最大值所在行列
A=A6(i-128:i+128j);%抽取列距離向
B=A6(ij-128:j+128);%抽取行,方位向
A1=fftshift(fft(A.‘));
B1=fftshift(fft(B));
D1=128;%插值倍數(shù)
R1=[zeros(1floor(length(A1)*(D1-1)/2))?A1?zeros(1floor(length(A1)*(D1-1)/2))];
B2=[zeros(1floor(length(B1)*(D1-1)/2))?B1?zeros(1floor(length(B1)*(D1-1)/2))];
R2=abs(ifft(fftshift(R1)));%%距離向插值后到時域
A2=abs(ifft(fftshift(B2)));%%方位向插值后到時域
r2=20*log10(R2/max(R2));%%距離向歸一化
a2=20*log10(A2/max(A2));%%方位向歸一化
%%%%%%%%%%%距離向分辨率%%%%%%%%%%%%%%%%%%%%%%
[max_rPOS_r]=max(r2);
r3=POS_r;
%%%%%%%%%%%%%%左邊3DB點(diǎn)%%%%%%%%%%%%
while(r2(r3)>-3)??
?r3=r3-1;
end;
rWidth_3db1=r3;
%%%%%%%%%%%%%找左邊第一零點(diǎn)%%%%%%%%%%%%%%
for?r4=rWidth_3db1:-1:1
????if?R2(r4) ???break
????end
end
zero_left=r4;
%%%%%%%%%%%%%找左邊第一旁瓣值%%%%%%%%%%%%%%
for?r5=zero_left-1:-1:1
????if?R2(r5)>R2(r5-1)
???break
????end
end
%%%%%%%%%%%%%左邊旁瓣能量%%%%%%%%%%%%%%
r_Sum_sidelobe1=0;?
for?rs1=1:zero_left-1???
r_Sum_sidelobe1?=?r_Sum_sidelobe1?+R2(rs1)?*?R2(rs1);%%%左邊旁瓣求和
end
%%%%%%%%%%%%%%右邊3DB點(diǎn)%%%%%%%%%%%%
r3=POS_r+1;
while(r2(r3)>-3)
?r3=r3+1;
end;
rWidth_3db2=r3;
%%%%%%%%%%%%%找右邊第一零點(diǎn)%%%%%%%%%%%%%%
for?r6=rWidth_3db2:length(r2)
????if?R2(r6) ???break
????end
end
zero_right=r6;
%%%%%%%%%%%%%找右邊第一旁瓣值%%%%%%%%%%%%%%
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
%%%%%%%%%%%%%右邊旁瓣能量%%%%%%%%%%%%%%
r_Sum_sidelobe?=r_Sum_sidelobe1?;
for?rs2=zero_right+1:length(r2)
r_Sum_sidelobe=r_Sum_sidelobe?+R2(rs2)*R2(rs2);
end
%%%%%%%%%%%%找第一旁瓣較大值%%%%%%%%%%%%%%
rMax_sidelobe=max(R2(r5)R2(r7));
rMax_mainlobe=max(R2);
%%%%%%%%%%%%
?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件???????5997??2013-04-19?21:05??pointevaluate.m
?????文件???????5291??2013-04-19?23:15??pointevaluate_xy.m
?????文件????8388608??2013-01-07?10:37??評估結(jié)果.SAR_Result.dat
?????文件???????5795??2013-04-19?20:32??erweijifenpangbanbi.asv
-----------?---------??----------?-----??----
??????????????8405691????????????????????4
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