非常好的dds功率谱性能仿真，matlab源码

%------------------------------------------------------------------------------- function data = psdplotsetup(inparg); %PLOTSETUP Setup arguments to plot with PSDPLOT. % PLOTSETUP returns a structure DATA to be used with PSDPLOT % with the following fields: % DATA.FREQ = wplot (Frequency data) % DATA.FREQLABEL = xlab (Frequency axis --x axis-- label) % DATA.FREQLIM = xlim (Frequency axis --x axis-- limits) % DATA.MAG = Pxx (Magnitude data (possibly in dB)) % DATA.MAGLABEL = ylab (Magnitude label) Pxx = inparg.Pxx; w = inparg.w; % Generate the correct labels if strmatch(lower(inparg.units),'rad/sample'), xlab = 'Normalized Frequency (\times\pi rad/sample)'; w = w./pi; ylabend = '/ rad/sample)'; elseif strmatch(lower(inparg.units),'hz') xlab = 'Frequency (Hz)'; ylabend = '/Hz)'; end % Scale the psd correctly if strmatch(lower(inparg.yscale),'db'), Pxx = db(Pxx,'power'); ylab = ['Power Spectral Density (dB' ylabend]; elseif strmatch(lower(inparg.yscale),{'linear','squared'}), % 'squared' is allowed % for backwards compat. ylab = ['Power Spectral Density (Power' ylabend]; end data.freq = w; data.freqlabel = xlab; data.freqlim = [w(1) w(end)]; data.mag = Pxx; data.maglabel = ylab; % [EOF] psdplot.m