diff --git a/DIPCV/lab2/lab2_9.m b/DIPCV/lab2/lab2_9.m
new file mode 100644
index 0000000..67ee850
--- /dev/null
+++ b/DIPCV/lab2/lab2_9.m
@@ -0,0 +1,10 @@
+close all
+clear
+clc
+disp('====E4_5_2.m====');
+I=imread('tire.tif');
+J=histeq(I);
+subplot(2,2,1),imshow(I),ylabel('原图像');
+subplot(2,2,2),imhist(I);
+subplot(2,2,3),imshow(J),ylabel('直方图均衡图像');
+subplot(2,2,4),imhist(J);
\ No newline at end of file
diff --git a/Matlab/comm/lab7_0.slx b/Matlab/comm/lab7_0.slx
index 99d4294..f246eb8 100644
Binary files a/Matlab/comm/lab7_0.slx and b/Matlab/comm/lab7_0.slx differ
diff --git a/Matlab/comm/lab8_0.slx b/Matlab/comm/lab8_0.slx
new file mode 100644
index 0000000..922e37a
Binary files /dev/null and b/Matlab/comm/lab8_0.slx differ
diff --git a/Matlab/comm/lab8_1.m b/Matlab/comm/lab8_1.m
new file mode 100644
index 0000000..962b310
--- /dev/null
+++ b/Matlab/comm/lab8_1.m
@@ -0,0 +1,13 @@
+clc
+clear
+close all
+SNR1=linspace(0.001,5,30);
+for i=1:length(SNR1)
+    fprintf("round %d is runing...\n",i);
+    SNR=10*log10(SNR1(i));
+    sim('lab8_0.slx');
+    Ps(i)=E(1);
+end
+Ps1=1/2*exp(-SNR1);
+plot(SNR1,Ps,'-o',SNR1,Ps1,'-*');
+grid on
\ No newline at end of file