Wednesday, September 27, 2023

Re: Help in identying a jamming signal

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Hello,

Taking a quick look at your recording, I see some kind of pulsed signal
that follows a regular pattern. The signal is on for a period of ~548
usec, then off for two periods of this duration (~548 usec per period),
and then the same repeats forever (one period on, two periods off). This
doesn't look like anything that would remind me of LTE or 5G.

A wider recording might give more clues, since, since this pulsed signal
appears to be much wider than 2.5 MHz. If you have access to an ADALM
Pluto, you could use Maia SDR (https://maia-sdr.org/) to record. This is
exactly one of the use cases I had in mind when I started the project.

Best,
Daniel.

On 27/09/2023 13:21, veso266@gmail.com wrote:
>
> Hello there all, I hope someone can help me
>
> I am trying to watch some television on CH47 (679.25Mhz)
>
> I am in Slovenia and I am trying to receive and watch Federalna
> Televizija transmitting from Bosnia and Herzegovina (BiH)
>
> But there is very anoying signal bothering me, you can see the problem
> here: https://youtu.be/wt4vEfu7yEI?si=XDQ8wQ-rK-lb8LMW
>
> Instead of seing PAL and hearing sound, I see this anoying lines and
> hear digital data :(
>
> So I decided to bring my Airspy R2 to visually see and record some IQ
> data on whats going on
>
> So this is what I recorded:
> https://transfer.sh/dMhDtqnodK/baseband_679250000Hz_14-23-42_26-09-2023.wav
>
> Center frequency was 679.25Mhz but sadly I was only able to record about
> 2.5Mhz of Bandwith, because my phone could not handle full 10Mhz
>
> As you can see PAL was bearly able to get through this jamming signal
>
> At first I thought it could be 600Mhz 5G NR which is sadly right where I
> want to receive  (663 – 698 Uplink, 617 – 652 Downlink), but thats only
> for US, not Europe
>
> The next suspect could be 5G Extended Lower SMH (which has downlink from
> 698 – 716) but its 20Mhz above my signal, PAL only needs about 6-8Mhz so
> this should not be a problem
>
> Then I thought maybe LTE Lower SMH on 700MHz could be the culprit, which
> again doesnt make any sense (Downlink on 699 – 716Mhz)
>
> I hope something could be done
>
> At least to figure out what signal that is so I can complain to relevant
> local authorities
>
> I am there for a 3 more days, so if needed I can do more messurments
>
> Sadly I only brought Airspy HF+, and Airspy R2 with me nothing more
> capable bandwith vise
>
> I also have Samsung Galaxy S10+ if it can maybe help in messuring LTE
> signals somehow
>
> Thanks to everyone for anwsering
> --
> Sent from myMail for Android
>

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