Internet In The (Le) Tunnel

[RGG]

I know I must be a bit late to this party.

I'm just a little bit sleep deprived.
We enter the tunnel and I'm browsing the internet traveling in Le Shuttle.
After some time I realise that I'm still connected.
After more time we come back up to the surface and I've been connected throughout.
I'm trying to work this out.

Back home I google and find out there's 4g throughout the journey.
I never knew that - but how cool.

[mikef]

It switches from your UK provider to/from a French one about half way. I always jump from from my UK phone to my France phone when it switches. No idea why, they both have huge data allowances these days

[miniman]

Which makes it all the more tiresome that it seems utterly impossible to maintain a signal between Paddington and Reading.

[RGG]

miniman said:

Which makes it all the more tiresome that it seems utterly impossible to maintain a signal between Paddington and Reading.

Exactly.

I have to admit in my presently exhausted mind - my first visual thought were "the masts" in the tunnel.
How did they do it.

Time for bed and a big sleep, I think.

Afterthought -

I wonder what happens to the signal in a concrete tube?
Is is amplified?
Hopefully a technical bod will come along shortly.

Edited by RGG on Sunday 28th September 21:38

[eliot]

RGG said:

Exactly.

I have to admit in my presently exhausted mind - my first visual thought were "the masts" in the tunnel.
How did they do it.

Time for bed and a big sleep, I think.

Afterthought -

I wonder what happens to the signal in a concrete tube?
Is is amplified?
Hopefully a technical bod will come along shortly.

Normally they use a technique called "leaky coax" - which as the name suggests, is a long run of coax cable that leaks enough signal from itself for your phone - so like a very very long linear antenna.

https://www.roadphone.co.uk/leaky-feeder/

Edited by eliot on Monday 29th September 06:25

[Michael_B]

When I take the train to our Italy office, there is a strong Swisscom 4G signal from Geneva until the border half way through the Simplon tunnel, then nothing.

TIM 4G sporadically appears as the train approaches Domodossola and the signal remains intermittent all the way to the suburbs of NW Milan.

[RGG]

eliot said:

RGG said:

Exactly.

I have to admit in my presently exhausted mind - my first visual thought were "the masts" in the tunnel.
How did they do it.

Time for bed and a big sleep, I think.

Afterthought -

I wonder what happens to the signal in a concrete tube?
Is is amplified?
Hopefully a technical bod will come along shortly.

Normally they use a technique called "leaky coax" - which as the name suggests, is a long run of coax cable that leaks enough signal from itself for your phone - so like a very very long linear antenna.

https://www.roadphone.co.uk/leaky-feeder/

Edited by eliot on Monday 29th September 06:25

Thanks Eliot, yes I looked it up just before I went to sleep - very interesting.