psd calculaton using simulink block

Started by nand...@ymail.com February 2, 2010
hai,
i am new to simulik and am using matlab 7.0 version.I want to calculate psd (welch) of a .wav file in simulink. but i dont have welch estimator in signal processing tool box.
Also how to display the result? if i use 'fft spectrum' viewer, it displays frame by frame, but i want the overall.
hi,

>i am new to simulik and am using matlab 7.0 version.I want to calculate psd >(welch) of a .wav file in simulink. but i dont have welch estimator in >signal processing tool box.

There is a function pwelch in Signal Processing Toolbox, which You can use for calculating Welch PSD estimates within MATLAB scripts (m-files). You can also plot Welch PSD estimate in Simulink with the standard Spectrum Scope block by setting its parameters appropriately. For example, if You check Buffer Input flag and set Buffer Size = 1024, Buffer Overlap = 512 and Number Of Spectral averages = 3 then You'll get a 1024-point PSD estimate with 50% segment overlap on a 2048-point sequence.

>Also how to display the result? if i use 'fft spectrum' viewer, it displays
>frame by frame, but i want the overall.

I don't understand why do You want to use Simulink for this. Simulink is a good tool for simulating behavior of a system in time, but if all You need is to plot an overall PSD estimate of a fixed-length dataset then it would be much easier to write a simple m-file.

--
Alexander