Re: Detection of signal

M.L. wrote:
Hello NG (again) :o)

How would you DSP wizards go about solving this apparently simple
problem?:

A signal (time, sample-value) is given and in this a pulse is present
at an unknown time t. The shape of the pulse is not known nor is the
duration, only that it rises significantly above the noise-level, so it
should be recognizable, at least by manual inspection. I would like to
write a program that can detect this pulse.

So what strategy should one employ to detect this unknown waveform?
Since the exact shape is not known, cross-correlation is no good.. So
should I just detect when the amplitude rises above an average
noise-value? Or implement some sort of running diff. that will suddenly
rise with a sudden increase in the slope of the signal?

Any ideas? Any standard way to proceed?


There are really no standard ways. One way is to try to think of what a "worse case" waveform would look like and try to design a detector to the worst case. Some people would consider a burst of noise to be a worst case signal.

You can approach the unknown duration problem by using a bank of detectors that span some min/max duration.

Since you imply that your signal is high SNR, simple is usually good enough.



Thanks!

Best,

M.L.

.

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