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Radar Pulse Stream Comparison - RF Cafe Forums

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Daniel_T

Post subject: Radar Pulse Stream Comparison

Posted: Wed Mar 16, 2011 5:40 am

Lieutenant

Joined: Tue Mar 15, 2011 2:32 pm
Posts: 1

Hi all,

I am currently working on a project with the aim to write a Matlab program to be able to analyse ESM received data.
I have both synthetic and real data to play with, which has been de-interleavered and has the following info:
1. Time of arrival
2. Frequency
3. Pulse Width
4. Bearing
5. Emitter ID
6. Stream ID
7. Confidence (1 or 0)

So I am basically number crunching in software, with no consideration to hardware.
The tricky part comes in the form of missing pulses or gaps in the stream.
I can assume the PRI of pulses by looking at one stream and calculating the median between TOA.
I have to find a way to compare fragments of streams together to determine whether they are in fact from the same emitter.
I know of ways to fill the gaps with null data then use various techniques such as Discrete Fourier to 'estimate', but my objective is to compare fragments.
I have already written code to filter the data down and provide a user interface for streams/certain emitters to be analysed.

Just wondered if any one had any ideas for comparison methods - I've been told that a similar technique is used in DNA matching?!?

Regards,
Dan.

troy

Post subject: Re: Radar Pulse Stream Comparison

Posted: Thu Apr 28, 2011 4:38 pm

Captain

Joined: Mon Feb 25, 2008 4:53 pm
Posts: 8

It's been a while since I worked on a radar project, but at the time (1990s) we were doing encoded pulse spreading specifically to prevent signature ID. It was sort of a mixture of DSSS and FHSS. It would be statistically impossible to relate successive pulses more than a few PRTs apart (in the case of long range interrogation) unless you had the emitter's vector identified. At that point, why do you need any more information?

Posted 11/12/2012

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