There is always some counter evidence which disproves something…
On the two flights Shoreham to Oban and back, 400nm, up to 5500ft or so, I not once managed to get any wx data over 3G 4G or anything else. The telegram wx bot never worked. It would come back with the data requested hours before only when one was about to land…
So satellite phones still have their uses 
Peter wrote:
How would a low tower density produce slow speed? It would give you a poor level of service for sure – basically what we have in the UK countryside which is probably 90% (by land area, a
How would a low tower density produce slow speed? It would give you a poor level of service for sure – basically what we have in the UK countryside which is probably 90% (by land area, and away from motorways) GPRS-only…
Isn’t the real issue the bandwidth of the “backbone” network?
A lot of towers are joined up with microwave links, and there is a fibre connecting to the system here and there.
They probably had to beef up all that stuff for 4G to be any good.
But, on the topic here, and regardless of the network speed, there seems to be a problem in some places with a good signal but no data. Mainly seen in France, IME.
I don’t know the details but AFAIK the connection is initially always done with GSM, and then the client negotiates the data connection, using the usual ATDT*99# followed by DHCP etc etc. It has to be GSM (not GPRS 3G 4G etc) initially because there is no other way to implement incoming voice or sms. So I think blacklisting of devices at altitude is done at the initial GSM connection level. It would make sense. I believe @byteworks might know about this.
The UK didn’t have enough density and so had very poor data speeds compared with Germany and Nordics.
How?
Peter wrote:
But German UMTS was about 10x faster than UK 3G. Of the order of 10mbits/sec versus 300kbits/sec down and under 100k up. 3G/HSPA UK is 3mbits/sec down and 300kbits/sec up.
That was mostly related to cell tower density.
Here is the explanation of the different symbols from Apple.
alioth wrote:
Another thing I’ve noticed is when on 4G, the annoying “bip b b bip b b bip b b bip” sounds have returned in nearby audio equipment, which I thought was something that only occurred with GSM’s TDMA transmissions.
Maybe has to do with some kind of fallback to 2G for voice while you’re using LTE data, according to this quote from the above linked page (though it talks about 3G, but if that is not available I would suspect your phone to use 2G):
If your carrier or network don’t support VoLTE, your iPhone might use 3G for data during voice calls. Contact your carrier for more information about simultaneous voice and data.
Peter wrote:
Do you get 4G or LTE showing up on the same phone?
Yes. It’s an iphone 6.
I’m in the US at the moment, and I put a PAYG T-Mobile SIM in it: here, most of the time it shows “LTE” but sometimes it shows “4G”. There has to be a difference but from what’s been discussed above, LTE is the only 4G technology so I don’t know why there’s a different string. Back home with a Manx Telecom SIM it only ever shows “4G” (or 3G if it falls back).
Another thing I’ve noticed is when on 4G, the annoying “bip b b bip b b bip b b bip” sounds have returned in nearby audio equipment, which I thought was something that only occurred with GSM’s TDMA transmissions.
Peter wrote:
OK; I think Germany used the term UMTS whereas the UK called it 3G.
They mean different things. 3G, 4G etc. refer to “generations” of mobile data communication, while UMTS etc. refer to specific technical standards. The Wikipedia pages on 3G, 4G etc mention the various standards used.
The bandwidth numbers for 3G/UMTS were largely useless because they came with terrible latency. Only very specific use cases perform well with high bandwidth high latency connections.
In terms of mobile data, 4G/LTE was the real breakthrough and cannot be compared to everything we had before. LTE is as good as DSL and it is true, it also works 100x better when airborne.
PS: June 15th roaming charges in the EU will be history. That’s is a significant advantage for a lot of people.
