CFAR

CFAR方法实现
2020-09-06 15:20:13 +08:00
parent c70b7d34d6
commit 34c17ce82a
4 changed files with 243 additions and 0 deletions
--- a/OS_CFAR.m
+++ b/OS_CFAR.m
@@ -0,0 +1,72 @@
+%-OS-CFAR检测器均匀背景与杂波干扰目标背景下性能仿真-
+clc;
+clear all;
+N=32; 
+
+r=3;     %CMLD_CFAR检测器筛除掉r个较大的参考样本单元
+R=N-r;   %参考单元长度
+n=N/2;            %半滑窗长度
+k=3*N/4;
+T=16.2933;        %标称系数
+Pfa=1e-6;         %虚警概率
+syms T0
+g=Pfa-k*nchoosek(R,k)*gamma(R-k+1+T0)*gamma(k)/gamma(R+T0+1);
+x=solve(g);
+T0=double(x);
+M=1e4;             %蒙特卡洛仿真次数
+SNR_dB=5:1:35;        %信噪比
+SNR=10.^(SNR_dB./10);
+Simul_len=length(SNR);  %仿真长度
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%OS-CFAR ideal%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+for i=1:Simul_len
+    Pd(i)=OS_Pd_Fun(N,k,T,SNR(i));
+end
+plot(SNR_dB,Pd,'b');
+hold on
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%OS-CFAR simulation%%%%%%%%%%%%%%%%%%%%%%%%
+for i=1:Simul_len
+    count=0;
+    for j=1:M
+        lambda=1;       %产生噪声，长度为N
+        u=rand(1,N);
+        exp_noise=log(u)*(-lambda);
+        lambda=SNR(i);  %产生待检测单元
+        u=rand(1,2);
+        CUT=log(u(1))*(-lambda);
+        exp_noise(N)=log(u(2))*(-lambda);
+        exp_noise=sort(exp_noise);
+        if(CUT>T*exp_noise(k))
+            count=count+1;
+        end
+    end
+    Pd_sim(i)=count/M;
+end
+plot(SNR_dB,Pd_sim,'-*r');
+hold on
+%%%%%%%%%%%%%%%CMLD_CFAR检测器筛除掉r个较大的参考样本单%%%%%%%%%%%%%%%%%%
+for i=1:Simul_len
+    count=0;
+    for j=1:M
+        lambda=1;       %产生噪声，长度为N-1
+        u=rand(1,N-1);
+        exp_noise(1:N-1)=log(u)*(-lambda);
+        
+        lambda=SNR(i);  %产生待检测单元及一个干扰目标
+        u=rand(1,2);
+        CUT=log(u(1))*(-lambda);
+        exp_noise(N)=log(u(2))*(-lambda);
+        exp_noise=sort(exp_noise);
+         exp_noise1(1:N-r)=exp_noise(1:N-r);
+        if(CUT>T0*exp_noise1(k))
+            count=count+1;
+        end
+    end
+    Pd_sim_1(i)=count/M;
+end
+plot(SNR_dB,Pd_sim_1,'--g');
+hold on
+
+title('OS-CFAR 检测概率曲线,N=32,Pf=1e-6');
+xlabel('信噪比(dB)');ylabel('检测概率');
+legend('OS-ideal','OS-simulation','OS-1interference');