How are most mobile masts fed?

I'm talking about the backhaul/data connection to the internet, or whatever else you want to call it. I'm not really wondering about voice but I suppose that's interesting as well, so feel free to educate, educators.

I appreciate that there will be no short, solid answer to this, as it will depend on whether the transmitter(s) are on top of a telephone exchange, or on top of a mountain. Yes, I have used an amount of exaggeration to better explain my question, there.

What I'm asking is whether or not most mobile masts, say in a field but not in a ridiculously remote location, are almost always fed by underground fibre, or whether they ever relay data to each other, a bit like TV repeater transmitters have for decades. If so, is it only in extreme circumstances?

There was recently a mobile mast built close-ish to me (not one will will serve me very often, I just went to look at it out of interest), and from day one it had two small dishes on it below the mobile transmitting cells. They look to be pointing at too much of an upward angle to be receiving anything from another transmitter, but I did wonder what they were for. The 4G latency would be terrible if it was being relayed between masts, wouldn't it? You can see exactly where they mole-ploughed power to it, but I don't know anything about how they get the data link to it.

Here is a photo of the mast I'm talking about, if that helps. As I said, the dishes look to be pointing at a point far, far higher than any mobile mast. It's halfway up a small hill, in order to cover a village below, it's not underneath a mountain or anything.

Cheers for any useful or interesting info.

Edited by deleted (Fri 03-Jun-16 22:19:37)

What is used depends on location, but point to point microwave/wireless is used and that mast seems to have some on it.

Preference is usually for a fibre connection for reliability and ease of increasing backhaul capacity.

What gets used depends on relative costs and geography of an area.

Wow, I didn't think that would be the case. If you can access any specific information, that mast is in Bildeston (or rather just outside it), Suffolk. OS grid ref. is TL 9929 5047.

http://pedroc.co.uk/

is the site you want,

that is a Mobile Infrastructure Project Mast, for EE, 3 (MBNL) and Vodafone, O2 (Cornerstone)

Ah, cheers. I've got a tab open with that bloke's Twitter feed, but didn't know he had a site.

Fibre mainly. I'm always surprised by how many masts are fed by overhead fibre, that's increased recently too and will increase as Openreach refine their overhead fibre processes and continue signing deals with the various electricity companies to use their poles to deliver overhead fibre. Not always easy to spot as the fibre usually dives underground again about 30-50m prior to the mobile transmitter.

Thanks for the link to my site thomaswarne01.

Yep, standard MIP mast.
Kathrein dual low band for: 800MHz 4G and 900MHz 2G/3G. Vodafone/O2
Huawei tri band. High, high, low: 1800, 2100, 800 for EE/3
Most MIPs that I've found so far are microwave fed; the microwave feed route is usually on the planning application.Modern Microwave links can provide in excess of 1gbps each way so work well for many masts.

Your page is excellent, thank you, I've learned a lot.

I might have missed a notice, but I took photos of all the planning permission signs I could see, and the only mention of a microwave link (which I should have picked up on, in retrospect... I simply thought the latency would prevent it from being true 4G; obviously I was wrong) was literally the mention of "...1no microwave link by Telefonica O2 UK Ltd.". Before that they'd declared "3no Antennas". There is a separate notice on T-Mobile headed paper (which I was surprised to see), which didn't mention any number of anything, just a mandatory "objection" notice, re: paragraphs 17 and 18, which I can gather is a mandatory thing, because there's also a third notice from Arqiva saying basically the same thing.

I will re-visit it soonish, and check if I've missed anything, I'd love to know where the microwave signal comes from. Is there a rough limit on how far it can be? And must it be perfect line-of-sight? Exactly what does a microwave transmitter look like, on a mast transmitting to one like this? Cheers for any info, I know I'm asking a lot of questions.

If it helps, both providers list the cell name/site name is SUF0172. The Telefonica notice refers to the "cell number" as TEF70226, and the T-Mobile refers to the "cell reference" as BAB060. With the latter reference, I assume BAB refers to Babergh District Council, to save anyone a search for local info. The main Arqiva "Keep Out" sign lists it as site 301569 and MIP0172.

Edited by deleted (Thu 09-Jun-16 00:37:21)

In reply to a post by gazzyk1ns:

Exactly what does a microwave transmitter look like, on a mast transmitting to one like this?

One of those dishes is a transmitter and the other is a receiver.

Microwave links are narrow beams which is why the dishes are used as they focus the beam.

Terrestrial radio, TV and phone transmitters need to cover the maximum possible area so don't have a focussing dish.

( Satellite transmitters do as they have to limit their signal to a certain area. )

Thanks once again.

So... I almost daren't ask this, because theoretically I can work out the answer, but then theoretically I "knew" that this mast was "probably fed by fibre" last week.

Is one dish for the uplink and then one for the downlink of data, for that single mast, or have they built in the capacity for that mast itself to relay data to another? I ask primarily because it seems that you have photos of arrays on your site which only have one microwave dish, so that confuses things (for me) slightly. I do have a proper close-up of the top of the mast (but not as good as any on your site, which shows the colours of the cable tags/sockets, etc... and that doesn't seem to be in question, anyway).

Sorry again to asks basic questions which might have been covered elsewehere, and cheers.

Edited by deleted (Thu 09-Jun-16 05:46:44)

Yes, that's correct, one is a transmitter one is a receiver. It is possible to have a bidirectional dish but usually there is a transmitter and a receiver, and yours both point to the same place.

They will require direct line of sight, but potentially the link could be 100km or more with the right kit.

Microwave links are commonly used for other things too, eg the military like them as they are very directional and you can't "tap" them without interrupting them and thereby tipping people off.

They could decide to daisy chain them in the future if they wanted.

There is no reason that this would not be "true 4G", microwave links are easily capable of higher bandwidth and lower maintenance than 4G.

Ubiquiti do some microwave kit, they even let you play with proposed links on their site.

Airfibre products here: https://www.ubnt.com/products/

Link planner here: https://airlink.ubnt.com/

Edited by nemeth782 (Thu 09-Jun-16 10:33:42)

The microwave dishes are not one transmit and one receive, they are full duplex and one is for each operator/company,
So one dish is for EE/3 (managed by MBNL) and another is for Vodafone/O2 (managed by Cornerstone Communications LTD)

2 company's 4 operators.

and latency on microwave is believe it or not is becoming allot less than fibre, as there is not so many miles and hops/routers for a signal to go, as it is pointing directly to another mast, avoiding towns, hills and valleys, and the entire amount of bandwidth is managed my the operator/company, not subject to any slowdowns via a wholesale network such as BT Wholesale,

So, in theory, at a big relay station where lots of mast's point to, Operator A (EE/3 MBNL) would have a lets say 10Gb leased line with guaranteed bandwidth via a wholesaler, and that shared amount of bandwidth would be fed to 10+ masts via their own microwave, instead of having fibre at each mast, which is costly and not always feasible, and can be subject to slowdowns as it might not be a leased line at the site, just fibre, and by having the guaranteed bandwidth centrally they can manage it themselves and distribute it via microwave from site to site. so latency is very small and not noticeable.
and completely in control of the operator.

In reply to a post by thomaswarne01:

and latency on microwave is believe it or not is becoming allot less than fibre, as there is not so many miles and hops/routers for a signal to go, as it is pointing directly to another mast, avoiding towns, hills and valleys,

The guys making their money as "high frequency traders" depend on getting the lowest latency possible between financial exchanges.

One cross-atlantic fibre, named Hibernia Express, is designed to follow the great circle route for UK to New York, to help achieve this.

However, the companies tend to prefer microwave links, and want them to be in the straightest possible line. Here's a feel for someone who has been tracking the links between London and Frankfurt, and the sites used to send microwave across the channel:
https://sniperinmahwah.wordpress.com/2016/01/26/hft-...

The BBC had a program about this, which mentions the use of microwave between Basildon and Frankfurt - as Basildon is the home of some major stock exchanges (as is Slough). A 3 minute clip mentions that difference in latency to Frankfurt as
Fibre latency, Basildon to Frankfurt, is 8.4ms.
Microwave latency, Basildon to Frankfurt, is 4.4ms.

http://www.bbc.co.uk/programmes/p026qp2x

In reply to a post by thomaswarne01:

So one dish is for EE/3 (managed by MBNL) and another is for Vodafone/O2 (managed by Cornerstone Communications LTD)

MBNL run the shared Radio Access Network (RAN) infrastructure for EE and Three, but CTIL only run the physical tower/site and apparently none of the radio infrastructure. So its quite possible under the joint Beacon project that Vodafone and Telefonica UK (trading as O2) have decided to share a microwave connection. Or its possible one network has used fibre and one has used microwave for back haul. Whereas on an MBNL site its more likely that EE/Three will have engaged MBNL to deliver a shared backhaul connection.

CTIL is simpler than MBNL, as a physical infrastructure share. MBNL was originally set up as a site and 3G RAN share which reduces equipment cabinet / electricity etc costs, but 2G (EE only) and 4G is implemented independently; however for both networks. Not all EE sites are owned/managed by MBNL, and its unclear what the future holds here (probably commercially sensitive since the failed purchase of O2 by Three's owners CK Hutchison).

Sources: http://www.ctil.co.uk/ - and - http://www.mbnl.co.uk/

Wikipedia

The UK telecommunications regulator, Ofcom, states that it "encourages mobile network operators to share masts and/or sites where possible" [2] and the Mobile Operators Association (MOA) has published a paper on the subject.[3] There is some co-operation between networks. Mobile Broadband Network Limited (MBNL) is a joint venture between 3UK and T-Mobile (now EE), and O2 and Vodafone have established a joint team called Cornerstone. The two schemes are different in that MBNL shares antennas while Cornerstone shares sites but not antennas.

Edited by jchamier (Thu 09-Jun-16 14:41:02)

In reply to a post by nemeth782:

Microwave links are commonly used for other things too, eg the military like them as they are very directional and you can't "tap" them without interrupting them and thereby tipping people off.

Well, not always the case!

http://www.lamont.me.uk/capenhurst/original.html

Where we lived at that time (Penyffordd), I could see the tower glinting in the distance as I drove along the A550 towards Hawarden.

It looked like a ventilation system for whatever was underground at the Capenhurst (British Nuclear Fuels) site. But in retrospect, could see the microwave "windows" at the top.

Cheers!

Edited by Ancient_Mariner (Fri 10-Jun-16 19:58:22)

You understand most of the microwave links are run by BT don't you?

In reply to a post by Ancient_Mariner:

In reply to a post by nemeth782:

Microwave links are commonly used for other things too, eg the military like them as they are very directional and you can't "tap" them without interrupting them and thereby tipping people off.

Well, not always the case!

http://www.lamont.me.uk/capenhurst/original.html

Where we lived at that time (Penyffordd), I could see the tower glinting in the distance as I drove along the A550 towards Hawarden.

It looked like a ventilation system for whatever was underground at the Capenhurst (British Nuclear Fuels) site. But in retrospect, could see the microwave "windows" at the top.

Cheers!

I live nearby and had no idea. That tower didn't last long, I wonder why they bothered? At that time BT had been moving their trunk lines to fibre for years. I guess by 1994 that process was complete and the tower was redundant.

Edited by deleted (Fri 10-Jun-16 20:47:21)