getwindow.m

数字信号处理基于matlab 文件内容 /conv(卷积部分) dupconv 重叠保留法 freqcirconv 频域圆周卷积 freqconv 频域卷积 timecirconv

function [wn,d] = getwindow( len,db )
%UNTITLED1 Summary of this function goes here
%  This function return windos wn and D (2*pi/N)
%  len is the window length,db is the stop-band attenuation
if db<21
    wn=boxcar(len);
    d=2;
else if db<44
        wn=hanning(len);
        d=4;
    else if db<53
            wn=hamming(len);
            d=4;
        else if db<74
                wn=blackman(len);
                d=6;
            else error ('Stop-band too big')
            end
        end
    end
end