Identification of unknown frequencies

1

hey all, super noob experimentalist trying to gain a better understanding of the system.

I understand there’s a BW limitation of 2.4MHz, but I was wondering if its possible to scan a given region of frequency for a “hit” to identify a target before localizing? I’ve previously been trying to do this with just a standard SDR and HDSDR which has proven successful for getting me a signal, but then localization has been painful.

I have a general idea of a f0, but I know the true f0 will depend on each unique asset. I think they’re all within 2.4ish MHZ from an average f0 - can you find multiple frequencies wihtin that 2.4MHz even if you don’t know the specific discrete frequencies?

thanks for the guidance,
-Scott

2

This is theoretically possible, but not with the current version of the software as implementing this requires a bit of work.

But even if we did implement it, it would probably be unable to catch signals that transmit for less than ~3-6 seconds. Because once an active frequency is found it would need to tune all tuners to that freq, calibrate for coherence (which can take 3-6s), and then start the DOA algorithm.

So scanning would not really be that useful as by the time the system is ready, many signals would already be back to noise.

3

This is helpful information, thank you Carl. I’ll use a secondary system to “scan” for the carrier pulse and then attempt to use the kraken to lock into the identified signal.

In the future, it would be cool to be able to isolate one of the 5 antennas to do scanning and then the other 4 to a general localization. If it’s something of interest, then you could switch to the 5 antenna array and do full localization.

I understand that’s a big ask, so take it with a grain of salt… but it would be very cool.

Thank you again,
-scott

4

Scott, I wanted to ask a follow up question and see if you developed an efficient way to scan through frequencies to identify ones to target for DF. Is there a 3rd party software solution that will let you scan a chunk of the spectrum using the Kraken sdr hardware? Or did you wind up using a 2nd sdr altogether?