function out = CICdec(decf, diffd, numsecs,x,iwl,owl,wlps)
Hd = mfilt.cicdecim(decf, diffd, numsecs,iwl,owl,wlps);  %得到CIC抽取濾波器
Hd.FilterInternals ='SpecifyPrecision';
%改變?yōu)V波器中默認的字長數(shù)，長度為級數(shù)的兩倍
Hd.SectionWordLengths =[wlps wlps wlps wlps wlps wlps];  
Hd.SectionFracLengths =[8 8 8 8 8 8];  %改變?yōu)V波器中默認的小數(shù)部分長度
Hd.InputFracLength = 8;  %改變默認的輸入小數(shù)部分長度
Hd.OutputFracLength = 8;  %改變默認的輸出小數(shù)部分長度
x_real = real(x);
x_imag = imag(x);
out_real = filter(Hd,x_real); %實部和虛部分別濾波
out_imag = filter(Hd,x_imag);
%得到CIC的輸出，其中對CIC濾波器的增益進行歸一化
out = (double(out_real) + j*double(out_imag))/gain(Hd);