Not sure if this is off topic or not so please delete and forgive if it is!
Anyway, I’ve just got my limeSDR up and running on windows 10 with GQRX without any particular dramas.
I’m trying to check what frequencies my phone uses on 4g and find plenty of transmission ‘lines’ from the local base station:
I don’t have the world’s best aerial, but when I move the spectrum view to 832-862 MHz, which is where my phone
should be transmitting, I see a few odd small pikes but not my phone. I turn my phone on and off repeatedly, send receive emails on 4g, upload videos to youtube - no change on the spectrum. I tried analysing some of the spikes that I did see with wireshark and they seemed to be irrelevant.
Any ideas please?
Thanks!
Do you have any way of determining definitively which band or standard your phone is using?
Thank you for your reply. Well, yes, there should be. I’ve tried getting the local tower info which has been ‘tricky’. There’s also the ‘standard frequencies’ that the network _should_use. I should also check out the specs of my phone to see what bands it can actually use for 4g.
The other thing is that I’ve only just got the limeSDR and only just now been able to explore above 1800 MHz so I guess it’s early days. I probably need to get the sails better trimmed on my ship!
It seems like my phone is actually using band 3: (1710 - 1785 and 1805 - 1880)
This is not what I was expecting - the data seems to be in a band 0.2MHz wide comprising of about 30 different signals. It’s also intermittent, which makes sense and always comes on when I press the ‘check email’ button on my pc (The phone is my modem).
I just hope I’m not picking up some kind of signal from the PC itself?
If anybody could confirm that this is a 4g cell phone Rx signal, then that would be really great!
In the meantime, here’s the Base station Tx’s:
Obviously, I wouldn’t be posting this message if I really knew what I was doing so any help is appreciated! It seems like some base tx’s have a stronger signal than others and I don’t know if this is normal - I’m guessing the base station can recognise a phone struggling to connect in an area of poor reception and so gives out a few more decibels to compensate?
Would this help http://www.evrytania.com/lte-tools/lte-cell-scanner w/ rtl-sdr.
I’ve used that to find my local big signal on 742.5e6
Thanks - I might give that a go on my Ubuntu enabled laptop with the limesdr.
To narrow the frequency range used by your provider you can take a look at http://www.spectrummonitoring.com/frequencies/ because all bands are split into smaller parts for different providers and countries.
Better would be to install an App like Netmonitor (for Android) which shows the used frequency Band like 1800 and the ARFCN. The latter can used to get the exact frequency used for up-/downlink communication with help of the calculator on http://niviuk.free.fr/lte_band.php.
Ciao,
Rainer
