It’s between Queensway & Holland Park.
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LU/Elizabeth Line 4G update
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I've got to say that's pretty ridiculous that the signalling equipment is so poorly RF shielded that LTE can interfere with it (assuming that is the problem, which sounds like it). To me that seems like one of the most basic tests this kind of equipment should go through.
I also wonder how fixable it actually is without spending a fortune (which noone has the money for right now and possible ever).
Wasn't there also endless interference problems on the Heathrow tunnel too with the existing ATP (iirc) system?
I suppose it may have to be fixed as the new emergency services network uses LTE and it will also interfere with that.
From insider sources, this, and on-train WiFi, is meant to go live Q2/3 2023.
All equipment is installed in the tunnels, it's just BAI and the networks not ready to switch it on yet.
Absolutely amateur hour, 2023 on a brand spanking new railway, the 'worlds first digital railway' and there's no phone signal in the tunnels
I do enjoy that Holland Park of all places has 4G ahead of any of the Elizabeth line, the place is a time warp
pethadine82
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Could signals be sent in the running rails at a certain frequency range and each carriage had WiFI antennas ? Not to familiar with the physics . But something like DOCSIS?
pethadine82
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Could you explain why?
It's infeasible. Track circuits mean that each signalling block's rails are isolated from the next with spacers, meaning that each block would need to have separate connection to a form of backhaul, plus the issue of making sure it doesn't interfere with signalling systems, plus general reliability, etc. It's certainly possible, but likely not to give any meaningful speeds to a 12-coach train full of commuters.
Saw Geoff Marshall tweeting about the 4G. Some of the replies are interesting:
Some people getting 5G already
Also someone suggesting they got 4G somewhere on the victoria line - not sure how accurate, anyone know if that is possible? Perhaps at oxford circus as I think that was listed in the next 'coming soon' batch?
Some people getting 5G already
Also someone suggesting they got 4G somewhere on the victoria line - not sure how accurate, anyone know if that is possible? Perhaps at oxford circus as I think that was listed in the next 'coming soon' batch?
Some handsets including my Samsung will claim you're getting 5G when it's 4G LTE. An app such as nPerf will confirm if it's 5G or not.
nPerf can't even confirm for sure. It's the way the 3GPP spec is written in regards to upper layer indication (ULI) and the "5G available" signal in LTE SIB2 signalling.
The only way to know for sure is using your phone's modem diagnostic interface.
I've found nPerf to be pretty accurate and reflects the info in network testing apps.
Vodafone and EE (well likely all) are testing standalone 5G, with Vodafone already live in a few places, and it seems the networks are planning how to use mmWave here - which might be something for congested platforms and concourses in the future.
Vodafone and EE (well likely all) are testing standalone 5G, with Vodafone already live in a few places, and it seems the networks are planning how to use mmWave here - which might be something for congested platforms and concourses in the future.
Vodafone will be running 5G SA on n8 at the least (but wasn't live in late December when I tested for it), with the limited trial customer set. EE won't (but might have the network misconfigured to broadcast SA signalling without their core authentication services).
The networks aren't really planning how to use mmWave here, really. Only EE has shown an interest, but we need at least two networks for anything to begin to happen due to equipment vendors and UE manufacturers not being interested at the moment.
Three has no interest in SA at the moment, and is currently deploying NR CA to all their 5G sites in the country, as well as continuing their densification projects with Ph7/8/9 builds nationwide.
TfL confirm 4G and 5G are available on the 'new' bits here - not JLE: https://tfl.gov.uk/info-for/business-and-advertisers/creating-a-connected-london
For the record, both they and the operators claimed 5G was available when it first switched on in December, but it wasn't actually available then. The network was under the impression it was (was telling devices to perform measurements for 5G), but no 5G carriers were actually live. This has the dual effect of showing a 5G icon but not actually giving 5G.
EE is incredible in stations though, hitting the theoretical maximum of close to 900 Mbps on 4G alone.
I was invited to a Qualcomm event today (couldn't go) which was discussing the UK plans for mmWave, so I hope to see the outcome in the next few days. As you say, only EE ever had it in their road map, but there does appear to be some interest in using it in very specific locations, and obviously Qualcomm has an interest in as much as most European 5G handsets don't have support - so any decisions made now will influence the devices we get in the next 12-18 months.
As for Three, their strategy for a dense network of poles is fine as long as they can get through all the planning issues, as there are often big gaps due to problems. As such Three can boast incredible speeds on 5G but in a very patchy way.
Three also has started to use carrier aggregation on 5G to get speeds up to or over 2Gbps. I expect EE will be doing this soon, and I'm already impressed with the 4G speeds offered on EE in more and more places, with speeds in excess of 400Mbps (and quite consistently, certainly not just at 1am or something). That has made the limited coverage on the tube all the more impressive and without even needing 5G (yet).
Oh nice, do let me know!
I am aware of an upcoming EE trial in the first half of this year, but can't say anything yet...
Are you basing your figures off that Ericsson Dots tweet from Saturday, by chance?
Three's performance is very good, but as you say patchy at best. They're also in a habit of misplanning at backhaul constrains at the moment, where they build two sites within 150m or so because two different teams worked on them, or where they upgrade a site to their max config setup, but fail to upgrade the backhaul from the 300-or-so Mbps originally.They already do! You can often find n28-n78 across the UK, typically also with n28 and/or DSS n1. Some sites also have dedicated n7 and n3, too. They've got a total of 6 NR layers now — basically just relying on better device capabilities now. I have a write-up about this (pre n7) from last year: https://davwheat.dev/blog/2022/04/19/ee-nr-ca
All the Three 'poles of wonder' near me that were once limited to around 300 are now unrestricted and topping 1Gbps with ease, albeit over a relatively small coverage area (seems to reach around 300-400 metres at most) so I hope they're addressing the backhaul issues. The problem is, even with a large number of these in my town there are still huge gaps because they don't overlap at all.
It's an odd rollout strategy as it will take potentially years to get the required density, albeit by the time they do the network is going to be incredible.. At least until either they can't afford to maintain all of them, or they partner up with Vodafone and decommission loads of them!
I suggest I'm/we're now venturing wildly off topic here!
It's an odd rollout strategy as it will take potentially years to get the required density, albeit by the time they do the network is going to be incredible.. At least until either they can't afford to maintain all of them, or they partner up with Vodafone and decommission loads of them!
I suggest I'm/we're now venturing wildly off topic here!
I was getting full 5G on o2 between Gloucester Road and Bayswater on the circle line a couple of days ago. Perhaps coming from the surface - but was wondering if it could be from leaky feeder given Notting hill gate has been done. But apparently o2 can't even join the newer lines on TfL so maybe it was the surface after all.
I’ve had trouble on both Jubilee and Central lines in the past week when on phone calls, that as I depart a station the call drops out (and the signal bars go down to none) and then the signal then immediately goes back to full. The phone call never ends however (unless I hang up) but the call never carries on.
I’m on an MVNO that doesn’t support Wi-Fi calling so it isn’t an issue with it patching over to a Wi-Fi call and then dropping off as the train leaves the station.
I’m on an MVNO that doesn’t support Wi-Fi calling so it isn’t an issue with it patching over to a Wi-Fi call and then dropping off as the train leaves the station.
There seems to be a lot of work going on right now, and some stations are only covered within the station and not in the tunnels - so I guess they have to configure things so you can hand off from one cell to another seamlessly - and maybe they haven't done that yet? Or it might just be a problem they're working on.
JonnyM
Member
I reckon they are still making tweaks, I travel regularly on the west end of the Central line and there are times at either Holland Park, Queensway or Notting Hill Gate that the signal suddenly drops like a stone while at one of these stations. In tunnel reception has been solid though. Still no sign of signal at Tottenham Court Road or Oxford Circus, although there have been further anntena installations at TCR. On Vodafone if that makes any difference.
It's because there's no handover programmed between the leaky feeders (tunnels) and the stations. As you're in a station, you're connected to a DAS (distributed antenna system) located on the ceiling (pics below).
When you enter a train and depart down the tunnel, your phone clings on to that DAS system's signal until it physically cannot anymore, then it enters a searching mode, which then picks up the leaky feeders in the tunnel. These feeders are split when you reach roughly half-way between most stations, which results in the same situation leaving one station's feeder system and re-attaching to the next set of feeders.
For a seamless call and browsing experience, networks need to set up handover from one system to the other, which can be done, but seemingly hasn't been yet.
I used to work for someone whose previous role was engineering those sort of handovers, I recall that he said they were triggered by signal strength thresholds. It seems likely that they are gathering data on how the handset signal behaves while aboard moving trains, so that sensible thresholds can be designed.
According to his stories, the thresholds offer quite a lot of flexibility, and some designs of his were specifically adapted to ensure that handsets aboard mainline trains entering short undercrofts would try harder to remain connected to the same cell tower, rather than have to swap back when re-emerging into the open. In other scenarios, at festivals care was taken to keep much of the traffic confined to the dedicated temporary cells erected there (rather than roam too easily to the permanent cells in nearby villages).
JonnyM
Member
Thanks. That is interesting and good to know. The inner geek within me has been wanting to take pictures of the antennas on the ceilings but I'm conscious that I'll probably get caught on some LU CCTV.
Anyway, do you know why some are metal boxes, and some are white? Like the pics above? Also, at TCR on both the Central and Northern line platforms there are three boxes. Two of them are like the ones above, but the third is slightly smaller and seems to be made of plastic. Any idea what the third box is for? There are also three boxes at Notting Hill Gate, but only two at Holland Park and Queensway.