改进这段的代码 function [At,Ph,A2]=EnvelopPhase(X,f0,fs) HX=imag(hilbert(X)); t=0:1/fs:((length(X)-1)/fs); Ac=X.cos(2*pi*f0*t)+HX.sin(2*pi*f0*t); As=HX.cos(2*pi*f0*t)-X.sin(2*pi*f0*t); Ph=atan2(As,Ac); A2=Ac.^2+As.^2; At=sqrt(A2); end function X=Narrowbandsignal(N,f0,delt,fs,M) N1=N-M; xt=randn(1,N1); f1=f0*2/fs; df=delt/fs; ht=fir1(M,[f1-df f1+df]); X=conv(xt,ht); X=X(1:N); end N=10000; f0=10000; delt=400; fs=22000; M=50; al=2; a2=4; a3=8; sitl=pi/6; sit2=pi/4; sit3=pi/3; X=Narrowbandsignal(N,f0,delt,fs,M); X=X/sqrt(var(X)); t=0:1/fs:((N-1)/fs); X1=X+alcos(2pif0t+sitl); X2=X+a2cos(2pif0t+sit2); X3=X+a3cos(2pif0t+sit3); [Atl,Ph1,A21]=EnvelopPhase(X1, f0, fs); [At2,Ph2,A22]=EnvelopPhase(X2, f0, fs); [At3,Ph3,A23]=EnvelopPhase(X3, f0, fs); LA=0:0.4:12; GA1=histcounts(Atl, LA); GA2=histcounts(At2, LA); GA3=histcounts(At3, LA); figure; plot(LA,GA1,':',LA,GA2,'-',LA,GA3,'--'); title('包络的分布直方图'); LP=-pi/2:0.05:pi/2; GP1=histcounts((Ph1-sitl),LP); GP2=histcounts((Ph2-sit2),LP); GP3=histcounts((Ph3-sit3),LP); figure; plot(LP,GP1,':',LP,GP2,'-',LP,GP3,'--'); title('相位的分布直方图'); LA2=0:1:120; GA21=histcounts(A21,LA2); GA22=histcounts(A22,LA2); GA23=histcounts(A23,LA2); figure; plot(LA2,GA21,':', LA2,GA22,'-',LA2,GA23,'--'); title('包络平方值的分布直方图');

在这段代码中，有一些错误需要进行改进：

1. 在 EnvelopPhase 函数中，Ac 和 As 的计算存在错误，应该改为：

Ac = X .* cos(2*pi*f0*t) + HX .* sin(2*pi*f0*t);
As = HX .* cos(2*pi*f0*t) - X .* sin(2*pi*f0*t);

2. 在 Narrowbandsignal 函数中，ht 的计算存在错误，应该改为：

ht = fir1(M, [f1-df, f1+df], 'bandpass');

3. 在主函数中，alcos 函数不存在，应该改为：

X1 = X + al*cos(2*pi*f0*t+sitl);

4. 在主函数中，histcounts 函数用法存在错误，应该改为：

[GA1, ~] = histcounts(Atl, LA);
[GA2, ~] = histcounts(At2, LA);
[GA3, ~] = histcounts(At3, LA);
[GP1, ~] = histcounts((Ph1-sitl), LP);
[GP2, ~] = histcounts((Ph2-sit2), LP);
[GP3, ~] = histcounts((Ph3-sit3), LP);
[GA21, ~] = histcounts(A21,LA2);
[GA22, ~] = histcounts(A22,LA2);
[GA23, ~] = histcounts(A23,LA2);

经过上述修改，代码应该可以正确运行。