butterworth+chebcv的matlab 程序

				%实现Chebyshev模拟滤波器的去归一化并且进行双线性变换子程序u_buttap.m
				function[b,a]=g_bilinear(N,Omegac,epi,fs)
				[z,p,k]=chy_lingjidian(N,epi)
				p=p*Omegac;k=k*Omegac^N;
				
				fs=2*fs;
				ad=(fs+p)./(fs-p);
				zd=(fs+z)./(fs-z);
				kd=(prod(fs-z)./prod(prod(fs-p)));
				
				bd=[zd;-ones(length(p)-length(z),1)];
				a=poly(ad);
				b=poly(bd);
				b=b*kd*k;