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How London cracked mobile phone coverage on the Underground

I'm old enough to remember the first attempt at 'mobile underground'. Maybe I've forgotten the name but it was something like BT Phone Zone, though google returns zero relevant results, so perhaps it was called something else. In lieu of public call boxes, BT trialled a base station that was installed in some tube stations (almost certainly Oxford St and Tottenham Court Rd), and with the correct 'wireless handset' as long as you were within 10 feet of it, or thereabouts, you could make a call. I'm sure I remember a semi-circle painted on the ground that if you stood in, you were in range.

2 hours agoDrBazza

Whilst I have seen the Rabbit fittings others have mentioned I do remember mention of a "zone phone" and suspect we're recalling the same thing...

5 minutes agomark_undoio

Just to add a piece of data to support this:

> It turns out the phone signal inside the station can be better than the one above ground

I was surprised when I noticed I had 5G in the tunnel, ran a speed test and hit 641Mbps down!

https://www.speedtest.net/result/i/6831252952

8 hours agosaulr

That always hurts. I live in a particularly nice bit of London and there is virtually no mobile phone service other than voice and can only get 80 meg ADSL. Yet the mole people get better service. Grr.

7 hours agodgxyz

I almost moved into a nice warehouse space in farringdon once only to discover it only got 12 meg service somehow. I didn't even know you could get less than 80meg now.

21 minutes agozipy124

One might even suspect that the particularly nice parts of London are full of NIMBYs who successfully petition against the eyesore of mobile masts being put up…

(Circumstantial evidence is that a particularly extra nice part of central London has no tube station, ostensibly to keep the riff-raff out, and is the only area with a proposed station on Crossrail 2 that voted against having a new station!)

6 hours agoMagnumOpus

There's plenty of riff raff here. Like me :)

5 hours agodgxyz

That directly goes against the earlier post where you said you lived in a particularly nice part of town

3 hours agohotstickyballs

London has a very high ratio of extremely nice houses on a road opposite council houses, or former council houses. There can often be a very large mix of housing in one area.

20 minutes agozipy124

There are a good number of places in the world where people of varied incomes live relatively close.

2 hours agoceejayoz

London tends to get that because it has never really been planned. It just grew over the course of 1600 years and absorbed other areas as it went. There are plenty of areas where a row of £20m+ homes are opposite blocks of 3-bed flats that go for a hundredth of that price.

Hundreds of years ago, before the rail or underground network, you still needed plenty of working class to live near where the rich people lived as the rich people still needed shops, servants, etc.

Having the city split into individual boroughs means that each borough had to provide for the full economic spectrum. The really expensive boroughs still have plenty of social housing and arbitrary divisions of land mean that things but up against each other from different boroughs.

However, new developments don't always get it right, when big green-field or brown-field sites are converted to residential they often struggle to get the correct right, and you end up with bigger areas that only cater for a subset.

National planning laws are also circumvented or gamed. If a new site requires a certain percent of "affordable housing" the developers will often agree (with the local borouhgh/council) to roll that over with another couple of projects and then build most of the "affordable housing" all in one place, and the diversity of individual areas is diminished.

As you say, there are plenty of other places in the world where this is the case, most of them in countries/cities that have existed for hundreds or thousands of years.

an hour agoalexfoo

> London tends to get that because it has never really been planned.

Not particularly true.

Go to a city in the world that REALLY has "never been planned", then come back and tell me London hasn't. ;)

36 minutes agotraceroute66

Is it practical to pay BT or HyperOptic to run fibre to you? If enough households commit to a contract they’ll sometimes do it for free.

an hour agosignal11

I have the opposite problem where I can only get HyperOptic. Not even OpenReach stuff. No problem with bandwidth but zero price competition, and 5G broadband isn’t viable either.

Going from £70/mo for gigabit to £65/mo for 500mb is insulting.

5 hours agoljm

Wait, why can't you get Openreach ? Even if it was a new build by idiots who forgot to push the "Free fibre, yes please" button when breaking ground you should have DSL at least.

2 hours agotialaramex

As a generalisation: OpenReach prioritise areas that have no fibre.

If Hyperoptic (or someone else like Community Fibre or The 4th Utility, etc) are in an area then OpenReach will put that area nearer to the bottom of their todo list.

It's better if they concentrate on putting fibre into areas that still have 7Mbps wet string DSL than competing in an area that already has one or more Gbps fibre options.

Even then, OpenReach tend to do FTTC first. Then it's case of what the last mile is formed of:

If it's via telephone poles then they get the fibre concentrators installed on the poles (which involves digging up the roads to get fibre to the poles) and then they're ready for the individual fibre runs to each property as and when they want to be connected.

You can see the differences in Google Streetview images in a residential road like: https://maps.app.goo.gl/RK8J8TXZUY6iF3pTA where the the June 2024 images show the fibre concentrators at the top of the pole, and then going back to the 2015 images or before where they aren't present.

If the last mile is underground then the fibre concentrators have to be installed in the service ducts (it's easier for them to deploy fibre alongside their existing copper pairs) and the last 5-50 yards to the actual premises is an absolute lottery, especially as many house redevelopments bury existing underground cables under concrete and other structures and twist/kink things in a way that copper is fine to deal with but there's little chance you can run anything else through whatever conduit is there, let alone something without corners too tight for fibre.

Compare the above overhead wiring fun with a street such as: https://maps.app.goo.gl/oDchjxtaoxPD5Pe86 where there are no telephone poles.

40 minutes agoalexfoo

Reading this hurts. I'm on £26 a month for a gigabit connection in Z4.

2 hours agomarliechiller

Urgh hyperoptic is dog shit as well. CGNAT or pay extra on top of already insulting prices.

5 hours agodgxyz

> Urgh hyperoptic is dog shit as well

Sounds like they haven't changed !

I recall helping out a friend to review a Hyperoptic proposal for their development.

Hyperoptic's idea of "optic" was fibre to a switch in the basement and then unshielded CAT5e to the users premises.

If that wasn't bad enough, even to the untrained eye, you did not need a measuring tape to see they would have exceeded the CAT length limit by quite some margin for many of the users.

And that's before their claims of owning the external fibre when in reality they were just contracting an ethernet service from BT.

So yeah, I would not touch Hyperoptic with a bargepole. I suspect the other altnets are no better .... "sell, build, disappear off to the sunset" was the impression I got.

Reading some of the reviews on the internet about post-sales support I'm not surprised in the slightest that users often struggle to get support once the salesdroid has long departed their doorstep.

40 minutes agotraceroute66

I feel like I'm going crazy. Hyperoptic is fine. I pay 40 quid for gigabit, and it's stable and fast.

an hour agomaleldil

Like many of London's woes, that's because of planning, councils have to approve infrastructure and block it: https://www.londoncentric.media/p/why-exactly-is-londons-pho...

I'd say it's developing-world tier, but a lot of the developing world has really good 5G signal these days.

8 hours agoSecondHandTofu

There are also some absolute morons out there. Couple of local things around me...

First I went to one of the local town planning meetings in my area when they were rolling out FTTC. This one was due to a rather old person objecting to the placement of a streetside box which was not even outside her property and no one who it would have affected could see it or cared about it. I raised my objections about her being a NIMBY old fart and was asked to leave. She single-handedly blocked it for 5 years due to council connections. She dropped dead. Stuck on 20 meg ADSL until that happened.

Second, they built a 5g mast put didn't put any equipment in it and left it 3 months. Several local threads on Facebook from the tweakers about how it was causing all sorts of completely unrelated problems from tinnitus to covid to mind control. Then someone burned it. There is still no equipment in the cabinet or mast today, nearly 4 years on. No one got 5g.

7 hours agodgxyz

Second, they built a 5g mast put didn't put any equipment in it and left it 3 months. Several local threads on Facebook from the tweakers about how it was causing all sorts of completely unrelated problems from tinnitus to covid to mind control. Then someone burned it. There is still no equipment in the cabinet or mast today, nearly 4 years on. No one got 5g.

Reminds me of this infamous decade-old story:

https://web.archive.org/web/20161010203002/http://mybroadban...

6 hours agouserbinator

This is standard advice among ham radio operators. If you're putting up a tower, put it up, mount the antennas, run the feedlines, but resist the temptation to operate for a while. Or use it for receive-only.

Log your activity, or lack thereof, meticulously. Perhaps a critical part was back-ordered, or more expensive than expected, and note in the log how it still hasn't arrived so you still aren't able to operate. If complaints come in, get them to be maximally public about it, ideally in a town meeting or something, then whip out your logbook and coup-fourré. Let the wackos show themselves to be wackos, then quietly start operating some time later.

2 hours agomyself248

PvP systems are absolutely exhausting. What a waste of energy

2 hours agoHPsquared

This happens a million times all over the country by YouTube and social media addicted morons. Who go on to complain about how "nothing ever gets done in this country" and they want the "good old days" back.

Except in the good old days things just got done when there was demand for them and NIMBYs were told to fuck off.

5 hours agophatfish

I'd say it's developing-world tier, but a lot of the developing world has really good 5G signal these days.

They also have a much bigger population using exclusively mobiles rather than landlines, since their infrastructure developed when the former was already available, and it's cheaper to just put up a few towers than run one landline to each subscriber.

6 hours agouserbinator

During Covid people were attacking engineering laying fibre because it was “5g”, and facebook had told them 5g caused Covid.

7 hours agohdgvhicv

tl;dr people reject installing ugly masts in densely urbanised neighbourhoods, meaning there often isn't enough capacity for everyone to get fast 5G.

7 hours agomgaunard

Great - what does customers do with 640 Mbps downstream in the metro then? :-D :-D

2 hours agoKellyCriterion

Take their laptops and do any big bulky downloads/uploads they have queued up.

an hour agoalexfoo

Pretty neat but as someone who commutes every day on the New York subway I hope it’s never “cracked” here. Phone usage without headphones is already annoying enough and I greatly appreciate the various people trying to take calls eventually lose service.

14 hours agodbish

It’s a tough choice, is it worse to hear their phone calls, or hear 2 seconds of every bit of TikTok/Instagram feed trash. Either way, no cellular access seems a plus.

13 hours agolostlogin

Honestly I'd prefer to listen to phone calls over brainless reels. Both are hell.

7 hours agothrow567643u8

The worst is not calls, it is the thousands of zombies hooked up on tiktok 24/7, of course with headphones, so completely unaware and indifferent to their environment, who block tunnels, escalators, turnstiles, etc.

7 hours agocm2187

In the 90s we read the paper and dumbed with our magnetic tickets. In the 00s we listened to MP3s while playing snake on an oyster. In the 10s we played Andy birds and listened to iTunes with a credit card at the turnstile. In the 20s we doom scroll and listen to Spotify while tapping out with our phone.

I don’t see the issue.

7 hours agohdgvhicv

All of that that they did while they sit. I don’t remember people reading the newspapers while slow walking in the middle of a corridor. And the problem with headphones is that they make people unaware of their surrounding, alone in the world, and therefore for instance unaware that there is someone on their left that they will cut the way to. Small incivilities, but repeat several times a day every day and it gets seriously annoying.

7 hours agocm2187

Certainly people would do that. And sending text messages in the 00s. People have been wearing headphones while commuting for a generation, and (not on the underground but certainly on trains) people in the 80s and 90s were far more obnoxious - get stuck on a busy train between people having conversations about inane stuff while smoking.

Public transport is far better today than it was 30 years ago, annoyances are far less than they were.

2 hours agohdgvhicv

> Public transport is far better today than it was 30 years ago

One exception.

Give me the Routemaster bus back.

The real ones, not the Boris ones.

Those who know, know. ;)

21 minutes agotraceroute66

People need targets to deflect the anger against themselves. Don’t take that away from them!

20 minutes ago47282847

Who still calls anyway? Literally all my friends exclusively message now (on WhatsApp).

It would be really annoying if I were out of touch for the whole duration of subway trips. But in my city it works great. Here the 3 main providers pooled together and shared the installation.

8 hours agowolvoleo

> Literally all my friends exclusively message now (on WhatsApp).

An annoyingly large number of them send audio messages. It’s worse for everyone involved.

11 minutes agokergonath

One or two people per carriage/bus.

8 hours agothrow567643u8

This behaviour is so bad on London (above ground) trains, if they ever do 'crack it' and roll out mobile signal to the Underground, those tiny carriages will be unbearable.

8 hours agothrow567643u8

There already is signal on many underground lines, and it’s pretty rare that people are playing things out loud in my experience?

8 hours agop10jkle

London, increasingly common. I’d say a third of the time when I take the tube. Combine that with people making loud calls, 100% of the time. But I find people imposing their music or tiktok videos more obnoxious than a builder discussing his next job a bit loudly.

7 hours agocm2187

A third of the time?

Sorry, nonsense. I use the tube several times a day and it's a real rarity.

I do worry about the tube becoming a cacophony of phone calls, but really? Everyone message now anyway so I reckon that'll be a rarity too.

7 hours agoLightBug1

I think it will depend on your route and the time of your commute. I see fairly distinct behaviour at different times on the tube & Elizabeth Line: come in or leave late and it's full of people who are much less considerate, go in with the majority and there's a bit more social pressure against being inconsiderate.

an hour agonmstoker

I also never see this behaviour, but I pretty much only use the tube for commuting at peak times. I think commuters are generally better behaved. The sheer density of people means that anti social behaviour will get angrily shut down very quickly.

5 hours agobspammer

It may also be highly dependent on which direction you travel. When you travel east from the city, you get totally different demographics than when you travel west.

7 hours agocm2187

Yes, the demographic plays a big role.

3 hours agothrow567643u8

Really? What do you mean?

6 hours agoLightBug1

They mean more immigrants live in certain neighbourhoods.

3 hours agoimmibis

My daily train to/from London Bridge to West Croydon is borderline unbearable.

8 hours agothrow567643u8

It's because phones speakers aren't loud enough to be audible over the sound of the tube itself!

It is noticeable on buses and overground when people play things out load, but to be honest quite rare in the grand scheme of things.

8 hours agohereonout2

That's true. I made several complaints about that to TFL before capitulating and just settling for noise-cancelling headphones.

Never been happier.

The clincher was noticing that the drivers themselves had access to ear defenders ... TFL said that that's because they're down there for extended periods of time. Sounds reasonable but I'm not buying that as a way out of not fixing the issue and exposing my ears to the worst bits of the tube.

Also has the ancillary benefits of blocking out those rare times (for me) when people do have their phone on speaker or are having a chat I'm uninterested in.

6 hours agoLightBug1

Somehow even though there's great cell coverage in Warsaw metro people aren't being obnoxious with it.

8 hours agoRicoElectrico

What is the thing with people using phones without headphones? And making calls on public transport? When did that become a thing? It’s the most obnoxious selfish behaviour and it shocks me every time.

It’s not just Gen Z either, I’ve seen a few boomers do it and even a couple of millennials.

6 hours agorhubarbtree

Ten of so years ago I was on a train and the women opposite me gave all her credit card details to someone over the phone — anyone close by could have had fun with them

6 hours agoyoungtaff

Is that still a thing in the USA that you can buy with just a credit card number, validity date, name and 3 digit code?

In the EU we have psd2 mandating a second factor. Usually an app where the transaction has to be confirmed.

an hour agomaster-lincoln

Yep. the US has always been behind on this bc both the card companies and the merchants are loath to spend an extra .01% to implement better security.

Apple Pay on mac is the best we got. Looking forward to getting a new mac this year in part just for that.

38 minutes agogorfian_robot

Not to excuse other people's behavior but buying a decent pair of noise canceling headphones or earbuds will make putting up with it a whole lot easier. You don't even have to listen to anything, or you can put rain noises and thunderstorms. It's as much better soundscape than public transport.

12 hours agoesperent

That also creates a problem that people then can not hear important announcements or be aware of dangers (such as knife wielding attackers, as happened on an LNER train just late last year)

9 hours agohexbin010

You can still hear those things, just not obnoxiously loudly. NC works best against static sounds. Speech still makes it through. Just not as loud.

If you're in a busy car enough people will hear it to be aware, and if you're on your own you will hear the announcement clearly.

Besides it's really a one in 10 million chance you'll get stabbed on the metro, not worth worrying about. The chance of getting hit by a car in traffic is much higher. That feeling of always being in some kind of danger seems to be very American, I never really see that in people here in Europe. I think it's the sensationalism in the press there, every little incident is blown up to massive "BREAKING NEWS!" proportions.

8 hours agowolvoleo

A deaf person wouldn't be able to either. We need better non audible ways of signalling.

7 hours ago7952

Noise cancelling headphones on NYC public transit is insanity.

11 hours agobuckle8017

Why?

8 hours agoTheFuzzball

You want to be aware of your surroundings.

4 hours agodbish

Why is your need for silence more important than other people's need to communicate?

11 hours agoedent

Neither of those things are needs, it’s just wants and preferring your own wants over others is completely normal.

Imagine trying to live your life where other people’s desires by default overrode you own.

10 hours agoRetric

Because silence is a common good, like clean air. It's everyone's. When people fill it with their noise they effectively privatize it for the duration. When they shout on speakerphone or play their music or blare sound from their apps it's especially selfish.

7 hours agonanna

Imagine trying to live your life where other people’s desires by default overrode you own.

Unfortunately that happens a lot; it's called the government.

9 hours agouserbinator

Collective vs individuals desires

8 hours agotrueismywork

Collectivism killed hundreds of millions of people, so I'll take individualism thanks.

3 hours agoimmibis

They can use headphones. The problem is listening to someone scroll through tiktok with volume on max.

8 hours agoCalRobert

Simply being polite. Understanding there are other people in the world you inhabit. Things like that.

4 hours agodbish

Etiquette. Some are raised with it.

8 hours agothrow567643u8

Their silence disrupts no one, but one call or loud song disrupts 20-40 people their peace.

Don't be a douche.

8 hours agojorvi

It's actually against byelaws to play music or other loud sounds on transport in London and they can prosecute you if they so wished...

It's about acknowledging it's a shared resource and respecting the space. No loud noises, no littering, no being drunk etc

These days people act like they're the only ones travelling

9 hours agohexbin010

Looks like TFL issued a whopping three fines in total last year...

https://www.bbc.co.uk/news/articles/cdx4lje9jpjo

7 hours agonanna

I know, it's pathetic. It's partly because they don't want to pay for the staff to do the enforcement and partly probably some other reasons.

In classic British style they just try to influence and nudge people with campaigns and posters. That way the organisation doesn't have to deal with awkward accusations of racism etc

5 hours agohexbin010

You do understand that one of those “needs”affects others around you, and one of them leaves them in peace, right? Also I’m sure parent wasn’t referring to emergency calls

9 hours agocatoc

You’re be a bit contrarian there and I’m quite sure you actually believe it’s far more nuanced than that

6 hours agoyoungtaff

I had assumed the delay was technical but it turns out it was mostly about finding a business model that worked for everyone. It is good they finally settled on a shared infrastructure approach so they do not have to crowd the tunnels with extra equipment.

14 hours agodfajgljsldkjag

I wonder if they considered using the existing metal tracks as antennae, or even https://en.wikipedia.org/wiki/Power_line_communication to feed base stations in the trains themselves.

So the ESN in the tunnels runs at 400 MHz, far lower than the 700 to 3,600 MHz range usually used by smartphones.

It's worth noting that 450MHz was listed as one of the GSM bands, but apparently was never used: https://en.wikipedia.org/wiki/GSM_frequency_bands#GSM-450

8 hours agouserbinator

> It's worth noting that 450MHz was listed as one of the GSM bands, but apparently was never used

It's specified for 4G/LTE (Band 31, 72 & 73) and 5G (Band n31 & n72) as well! The bandwidth is pretty low though at just 5 MHz, but it's used for special purpose stuff like electricity meters. I'm not aware of any consumer devices that use this frequency.

2 hours agofundatus

Weird because very few phones have that band. Requires much larger antennas. Twice as long as for 800Mhz.

Edit: ah I see why, this is exclusively about the Emergency Services network, not for regular phones.

In that sense it seems a bit similar to GSM-R used by the railways here.

6 hours agowolvoleo

I use the underground frequently. It doesn't really feel like half of it is covered. Where it is available, it works amazingly. I might have been using the other half by sheer luck.

8 hours agocagz

I find it works pretty well, at least that I’m consistently surprised I have any signal at all. Sometimes I need to disable private relay to get it to work with all the switchovers. There’s also frequent swapping between the 5G signal and the Wi-Fi that comes auto-enabled on my phone by my carrier who provides a client certificate entitling me to it.

I’m not sure about the privacy implications of this whole setup. It’s basically turned the underground into a surveillance dragnet that can hoover up all sorts of interesting metadata… hostnames, hardware identifiers, traveling patterns, DNS queries, SNI requests… and an untold amount of unencrypted communications across weird protocols and devices..

an hour agochatmasta

This is the new system for emergency communications? TfL just finished up an upgrade on that in 2021. That upgrade was built by Thales.[1] That system is purely for operational use, and is not cell phone compatible. It's compatible with the gear cops and fire brigades use. Is it being replaced?

As late as 2018, the classic century-old system, with two bare wires on insulators on the tunnel walls, was still maintained.[2] Clipping a telephone handset to the two wires would connect to a dispatcher, and the wires were placed so that reaching out of the driver's cab to do this was possible. In addition, squeezing the wires together by hand would trip a relay and cut traction power. Is that still operational? The 2011 replacement was ISDN.

[1] https://www.thalesgroup.com/en/news-centre/press-releases/th...

[2] https://www.railengineer.co.uk/communications-on-the-central...

10 hours agoAnimats

The classic system does sound pretty elegant really.

7 hours ago7952

It always better to have a backup.

8 hours agoxvilka

Definitely not. Try it in Tokyo, every single line, every single station has high speed coverage. I can’t recall signal ever dropping out for me.

7 hours agocedws

London’s first line predates tokyos by like 60 years and was literally the test ground for how to make underground’s

The challenge isn’t the technology but rather the environment you’re trying to retrofit

7 hours agoHavoc

So if I follow, you’re saying that because London’s underground is older than Tokyo’s, it somehow changes the physical environment of the tunnels or their surroundings such that installing the required technology is more difficult?

Please expand…

7 hours agomft_

The way this is usually done is through a radiating wire that goes on the wall from station to station. This solution requires a lot of power. The stations in London are very small, leaving very little space for a transformer that can provide said power.

Because of that they rely on directional antennas that cover sections of the tunnel - but those need to be straight, otherwise another antenna is required to cover that corner. There is also very little head-room in the tube tunnels in London. You can see how things get more and more complicated as you dig deeper into the problem.

2 hours agoredleader55

You’ve not been in London’s deep underground lines I take it? Some of the tunnels are so ancient and cramped that tall people can’t stand straight in most of the carriages. As the article says there just isn’t space to add equipment. Same reason they’re struggling to add air conditioning to older lines - no clearance

The recently built lines had 5G etc from the start. It’s not difficult when the environment isn’t constraining you. Even malls add indoor 5g these days

5 hours agoHavoc

There is very limited clearance inside the tunnels, and a lot of electrical noise from existing systems.

6 hours agoTheOtherHobbes

The tunnels are particularly narrow and lived with iron rings. There's less space for adding equipment.

6 hours agoSymbiote

That's the standard excuse but it's the same on the Elizabeth line which was commissioned only a few years ago.

7 hours agocedws

I'm having a really hard reading this. Not only are the paragraphs are so short, they each feel like part of a uncompleted thought.

The content doesn't feel AI generated, but maybe it is? I read somewhere that short paragraphs is an AI signature!?

11 hours agomatham

> What happens if a train has to stop in the middle of the tunnel, and you phone for help? [...] the system has been deliberately configured to transmit the location of the nearest tube station, where access can be arranged. That’s why sometimes you might check your smartphone map, and it will display the “wrong” location, because that’s the best one for a 999 call to use.

This doesn't seem correct - cell towers don't just transmit a location that phones then pickup and use? Unless this is some emergency specific feature I'm not aware of?

2 hours agojoelkoen

> This doesn't seem correct - cell towers don't just transmit a location that phones then pickup and use?

I think it works like this: Towers transmit location. If the phone has no other source of location data, it'll fall back to "probably within radio range of this only tower I can hear"

an hour agobobmcnamara

Interesting! I know Sweden was not first, but Stockholm has had 3g coverage in the subway since 2005 and 4g since 2016.

9 hours agozith

Lots of countries do where the underground is near the surface, but London it is very deep.

2 hours agojustincormack

One of the frustrating things about international roaming in the UK is typically your plan does not include coverage on this neutral network on the underground

13 hours agodotBen

I was thinking it could be a radio band issue?

I had a fun situation when I had friends visiting me in Japan for a road trip. One friend's US-model Android phone didn't support the specific low bands used for sparse coverage in rural Japan, but the repeaters inside of the tunnels were all on standard 2100 MHz, so whenever we drove through a tunnel he rushed to his phone to get some messages through. Kind of the opposite to what you usually experience with loss of signal in tunnels :)

4 hours agokalleboo

Source? As someone that comes back to London every month, I’ve been able to roam the same as anywhere else in the UK. I’d be shocked if this were true.

10 hours agoinlustra

Did the UK stop people from just picking up a cheap SIM at the Airport? I always like a local number when traveling. Anyway, Indian Roaming plans are so cheap these days that it's much easier and cheaper to just subscribe to them as part of the plan. These days, I don’t even need to add/activate it or anything, the providers turn it ON when I start my phone outside India and turn it off when I re-activate back in India.

11 hours agoBrajeshwar

I think I saw vending machines with SIM cards recently in Heathrow airport.

6 hours agoSymbiote

I don't think that's correct.

With the old WiFi networks (Virgin, Vodafone WiFi, etc.), yes.

With the new 4G+5G coverage, you can access that the same as you access above ground coverage.

6 hours agomikelward

The main problem if you're roaming is that you're considered a lower-priority customer, and since the network is often saturated already, you don't get any bandwidth.

7 hours agomgaunard

They didn't. In the Bakerloo line there is no coverage save for wifi on stations, not on tracks.

an hour agocorimaith

Are the dual redundant leaky feeders configured to act as a MIMO array?

7 hours agotimthorn

From looking at the WiFi ssid’s broadcast at the New York subway stations, I believe Boldyn also does the phone coverage here too

14 hours agoTsiklon
[deleted]
14 hours ago

> There’s another distance limit at work here, and that is the speed of light. It takes milliseconds for the signal in your phone to reach the hotel above ground and be handed over to the mobile network.

It takes roughly 100us for light to travel 30km – Can you explain how the speed of light is relevant here?

8 hours agobede

.. and in 1mS it travels 300km. Maybe they just want to sound technical, somewhat to match the rest of the article. They certainly didn't use chat gpt, so maybe that's a good thing.

2 hours agomianos

Anyone who lives in London knows that phone coverage on the Tube is anything but "cracked".

8 hours agoiLoveOncall

As a resident with a phone problem I miss the underground not having any signal. Other people using TikTok doesn’t bother me so much because it’s relatively rare. My own tendencies with screen time bother me more. No internet actually forced me to read books more and I miss that.

But this is a lot better for tourists who need the internet to navigate underground. So I’m pleased for them.

8 hours agotestdelacc1

How London enabled TikTok addicts to annoy other passengers

9 hours agohexbin010

The Paris metro figured this out perfectly way back in 2021 - full bars, 5G.

9 hours agoinshard

The Paris metro is mostly cut-and-cover. It isn't very deep. The deepest tube lines are around 60m underground.

8 hours agoedent

Are you suggesting the mobile signal comes from above the ground in Paris?

2 hours agoredleader55

No. I'm suggesting it is easier and cheaper to retrofit equipment. Not to mention dealing with the extra heat.

38 minutes agoedent
[deleted]
9 hours ago

>There’s another distance limit at work here, and that is the speed of light. It takes milliseconds for the signal in your phone to reach the hotel above ground and be handed over to the mobile network. But if it takes too long to get from phone to hotel, then your phone call s..a.rt..s..t o. br..e..ak up. As it happens, that distance is about 12km, so Boldyn needs nine hotels around London to cover the whole of the Underground

I find that interesting. Another fascinating rabbit hole the article has sent me down is that there is an unused station called north end. I've been down that stretch before and i had no idea. Does anyone know if passengers can see it?

9 hours agoFridayoLeary

There's a small surface building that doesn't look like a station, platforms are visible if you're paying attention, and it can be used for emergency evacuations.

5 hours agoTheOtherHobbes

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5 hours agoegao1980

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