# convolution and groupdelay

I have been given a sinusoidal signal x in time domain,asked to investigate the frequncy responce of the signal using matlab and observing the result,and using grpdelay(x,1) command in matlab to observe the group delay of the signal .and taking y=conv(x,x);which define the convolution of x signal by itself and then asked to use the grpdelay(y,1). My question here is what change should I exspect to see in group delay figure of conv(x,x)? or better to say how convolving of the signal by itself would effect the group delay of the signal. Thanks

## 1 Answer

There is some confusion here. Frequency Response and Group Delay are properties of a System not the properties of a signal. You can only calculate the spectrum of a signal (magnitude and phase). A "signal" doesn't have group delay unless it's the impulse response of an LTI system.

• But you could view any signal as the impulse response of an LTI system. I think the question is valid. – user7358 Feb 21 '14 at 22:53