Trying to identify the mode of this signal.

KA7U · January 2017

Do you know what this signal is?

Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/a3/06613b1a06c1d261c95779bec0ac3d.png

KA7U · January 2017

I have not been able to identify this signal. I received it again tonight on a lower frequency.
Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/79/a11343be62734916bebb46afb7cb78.png

KA7U · January 2017

Here is another wide digital signal that I have not yet identified.

Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/17/13b8f2c1873cded9e480c4c465aae9.png

G8JNJ · January 2017

Hi,

You may find the Signal ID WiKi to be of help when trying to identify unusual signals.

http://www.sigidwiki.com/wiki/Signal_Identification_Guide

Regards,

Martin - G8JNJ

KA7U · January 2017

Martin,

Thanks for the link. I've used it, but it doesn't seem to include the signals in question. It is a very helpful site though.

Ron - KA

G8JNJ · January 2017

Hi Ron,

The first one looks a bit like a half bandwidth Link-11 signal. I have seen these too, but have not so far been able to positively identify them.

The second is almost certainly some type of Over the Horizon Radar. I conclude this because of the occupied bandwidth which is much greater than any of the other digital data/voice modes.

Take a look at the spectrum plot of the Danish system on this webpage

http://www.iarums-r1.org/iarums/radar-2012.pdf

Regards,

Martin - G8JNJ

G8JNJ · January 2017

Hi Ron,

It's Link-11.

I found an identical signal this morning and it meets the spec

http://www.lucabarbi.it/oldweb/th/TH_Link11.pdf

Regards,

Martin - G8JNJ

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/10/0f1adcb486bb49013c709f8a6d39e4.png

KA7U · January 2017

OK, this is a different signal. It varies in duration and there are long periods between transmission. It doesn't seem to fit anything I've seen before. Occasionally FSK preceeds it. While uploading this video, a G2-ALE signal came on just slightly off this frequency. I wonder if this is related.

Any ideas?

Ron - KA7U

G8JNJ · January 2017

It sounds a bit like either HFDL or CIS-3000, but the lack of sync tones and varying length of the data bursts suggest otherwise.

Can you zoom in adjust the waterfall Max / Min settings so that it's possible to see the while spectrum in more detail.

e.g. is it one continuous wide band OFDM type signal or multiple PSK carriers.

Regards,

Martin - G8JNJ

KA7U · January 2017

OK, Martin,

This signal proves to be a bit elusive. It starts at indeterminate times and runs for short durations, usually. Occasionally it goes longer. So I think the short runs are announcement, or ID, and the slightly longer transmissions are probably sending something more. Just guessing. Because the transmissions are short, it has been difficult tonight to get a good sample on video, but here is possibly enough to determine what it is.

Ron - KA7U

G8JNJ · January 2017

Hi Ron,

OK here's a screen grab of HFDL

I was suggesting that you adjust the waterfall Max and Min settings so that it may be possible to see any spectral lines and be able to count how many there are.

This and the occupied bandwidth would give further clues as to it's type.

If you want to wade through a lot of information here's a useful link.

http://www.wavecom.ch/content/ext/DecoderOnlineHelp/default.htm#!worddocuments/milstanagcodecheck1.htm

Regards,

Martin

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/0d/b78048780e267398b7c0c7ba7b4940.png

KA7U · January 2017

Martin,
This may well be a form of HFDL but it isn't the garden variety HFDL used by the Airlines. MultiPSK decodes that HFDL nicely but it doesn't track with this signal at all. This is a busy section of frequencies. I keep coming here to listen and look. I might check other KiwiSDR and see how it goes in different locations. I will start with yours.
Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/29/2e1c0490834f960816a78e895f7deb.png

G8JNJ · January 2017

Hi Ron,

Sorry I think I may have mislead you with my previous post.

I wasn't suggesting that it was HFDL, but I was using the screen grab to try and demonstrate what I meant about adjusting the waterfall controls so that it's possible to see more details of the modulation structure, which may help to narrow it down.

HFDL has a short burst of carrier before the main datastream, which I don't think is present on your transmission.

Regards,

Martin - G8JNJ

G8JNJ · January 2017

Hi,

Does anyone have any idea about these signals which pop up throughout the 2-30MHz spectrum.

They occupy about 8KHz of bandwidth, typically last about 2 seconds and often repeat every 10 to 20 seconds.

I suspect they may similar to the Jorn Over The Horizon Radar

https://en.wikipedia.org/wiki/Jindalee_Operational_Radar_Network

http://www.iarums-r1.org/iarums/radar-2012.pdf

But it's very strong here in the UK for the Australian site, so you may know better.

Regards,

Martin - G8JNJ

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/c1/e20bb03e1367656c6d8479f5f2aab2.png

G8JNJ · January 2017

Whilst monitoring another signal has popped up on an adjacent frequency.

This one seems to occupy a narrower bandwidth and has used three different sweep rates, which is more typical of JORN.

Regards,

Martin - G8JNJ

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/1b/c1a3715b74f8c12bc68f5c74aa3294.png

KA7U · January 2017

I don't know what it is either Martin, but I did see this signal @ 17:25 UTC this morning. I also saw the JORN type signal at that time but up frequency about 200 KHz. Both signals were substantially lower in amplitude than your reception. At the noise level actually.
Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/e4/b4c940087dc3e5e59712928cef145e.png

KA7U · January 2017

Martin, There are quite few signals that defy description. This one looks like an over sized Stanag or maybe 4 stacked signals? I don't know, but it is big and loud.
Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/cd/a63f543e938bd6c9d5b6413282dd39.png
https://forum.kiwisdr.com/uploads/Uploader/04/c4f2dd0f89a4f4f4b7acf666264f63.png

G8JNJ · January 2017

Hi Ron,

I think it's one of the Russian CIS modes.

The best candidate is probably CIS-128 as it has is about the correct bandwidth, has multiple modulated carriers with a missing carrier in the middle of the spectrum.

http://www.sigidwiki.com/wiki/CIS-128

The tag above the frequency says CIS-12 but this transmission is much wider, however if the CIS have been logged using one mode on this frequency they probably use other modes on it too.

You can usually differentiate between STANAG and CIS modes as the latter tends to have distinct vertical bands on the waterfall, the exact number depends upon the mode in use.

In contrast STANAG just tends to just look like a continuous block of noise.

The distinct ripple pattern across the waveform is due to multipath propagation causing phase cancellation and addition of the signal at various frequencies depending upon the instantaneous path length of the signals reflected off the ionosphere. This is what makes me think the source is not 'local'.

Regards,

Martin - G8JNJ

KA7U · March 2017

Here is a new one I found tonight. The digital would run for a bit and then a robot voice in spanish would say quattro and another word that I never made out.

Time was about 5:45 UTC.

Ron - KA7U

Attachments:
https://forum.kiwisdr.com/uploads/Uploader/64/a122a17f37ad9a068ce0acbf9aaaaf.png

G8JNJ · March 2017

Hi Ron,

It's HM01, Radio Habana in Cuba.

One of the remaining numbers stations.

The tones could be to trigger a recorder or similar at the RX.

Regards,

Martin - G8JNJ

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