akachyan schrieb:
> Hi,
>
> I have a sinusodal signals with fixed frequencies(multi-tone).
> But the signal is randomly on and off.
> What I did is that once the signal is off, I discarded the portion and,
> then, when the signal is on, I attached the signal afterward.
> So, now, the signal becomes phase discontinued, same frequency,though.
>
> My frequency tracking algorithm works with the original sinusoidal
> signals(without off). Not it cannot track the phase-discontinued signal
> properly.
> Is there any way to track the frequency of the signal?
>
> Thank you in advance.
> timothy
>
>
>

The question is what are you trying to achieve? Do you want to know when
a frequency component is on/off. Or do you want to track the exact
position of the relevant components in the frequency domain?
If the second is the case I would suggest you a Kalman-Filter with a
Multi-Target-Tracking Association. That way you can extrapolate the
frequency positions for frames where your component is off.
Otherwise there must be an easier solution.

Greetz,
hagbard