Microwave Backhaul

InfamousTeal · 04-06-2015, 13:55

Hi everyone, thought I'd make a new thread for this rather than asking on the end of Three 4G thread for example, cos it applies to all networks really.

I'm interested in the whole Backhaul section of networks, particularly microwave atm. Here in N Ireland, the MBNL masts all have at least 1 /2 microwave dishes on them, I'm guessing fibre is going in somewhere, and practically every single mast around here is "looking at" each other.

Planning permission shows which masts are looking at who. (there aren't many masts so it's not hard!)

I was wondering, because of this daisy-chain like setup, if a mast goes down, say for maintenance, upgrades, just engineers changing something for an hour, does that knock out the microwave? Surely if the power is off, it would? Which.. Would mean so many more masts would suddenly lose their Backhaul.

I'm trying to work out which mast is getting fibre around here, by mapping the microwave paths of each one.

But I know for sure that my local mast went completely down for maintenance last week, for a day, and it's part of a daisy-chain of microwaves, spanning about 20 miles west. So, did half of the north west suddenly lose Backhaul? Or , does the microwave transmitter have a different power source?

Sorry for the waffling

wrexham103.4 · 04-06-2015, 16:48

They daisy chain around here too, right pain in the arse when u don't have any signal for a 15 mile radius. Vodafone and O2 seem to be ok when power is lost

InfamousTeal · 05-06-2015, 12:20

So does anyone know if powering off a mast knocks out microwave?

I've found one near me that's "looking at" at least 6 different towers

DevonBloke · 05-06-2015, 14:54

I don't know but my guess would be it depends on the kit and how it's set up.
I would imagine the whole backhaul part that the MW dishes terminate in were separate to the the actual 2G/3G/4G rack unit. The cellular modules would plug into them via optical or Ethernet surely?
So you could power off the cellular without affecting the MW link.
Just a guess but seems sensible.

lost boy · 05-06-2015, 15:05

Quote:

Originally Posted by InfamousTeal

So does anyone know if powering off a mast knocks out microwave?

I've found one near me that's "looking at" at least 6 different towers

I'm no expert, but I'd say it would depend on if there's any redundancy or not.

I know T-Mobile, back in the day, used to have a LONG daisy chain going on here, which due to overloading and other technical issues at the 'hub' (for want of a better word) of the chain means that the whole chain used to have no end of problems. Eventually they gave in and erected a new 'hub' more locally, and most of the problems went away. To be honest, the only thing that completely knocks out the T-Mobile half of EE here now is a power outage.

Icaraa · 05-06-2015, 18:27

O2 uses BT for backhaul whereas the others use Virgin Media or Vodafone (C&W) fibre instead where they can. They probably daisy chain and then get onto one of those networks to avoid BT fibre charges.

moox · 05-06-2015, 20:07

Quote:

Originally Posted by DevonBloke

I don't know but my guess would be it depends on the kit and how it's set up.
I would imagine the whole backhaul part that the MW dishes terminate in were separate to the the actual 2G/3G/4G rack unit. The cellular modules would plug into them via optical or Ethernet surely?
So you could power off the cellular without affecting the MW link.
Just a guess but seems sensible.

There's a document flying around from MBNL showing how to connect and configure NEC Pasolink radios for EE/3, so that would confirm it

(it would also make logistical sense to order the 3G/4G base stations with a standard configuration and use separate units for whatever backhaul was available)

Redcoat · 05-06-2015, 21:20

Some sites MBNL use in Northern Ireland can be quite remote to access and/or not be close to fibre links. Nearly all the ex-Orange sites that were upgraded had included larger microwave aerials to be installed presumably to allow better wireless links with faster throughput and reliability.

I've generally assumed in cases like this for MBNL in rural areas, there is a relationship between cell sites similar to that for the UHF DTT network, where there are "main" mother cell sites that are connected to fat fibre connections in towns on reasonably high locations, with cell sites in more isolated areas where fibre connections can't be reached without excessive cost are connected to the main cell site via microwave link in a similar way a UHF TV relay station is connected to a main station for its feed to broadcast, with in most cases this microwave link to the mother station being only one link but in some cases two and in extreme cases three or even more. There will be plenty of instances though that a microwave aerial will be present even if the cell site is linked to fibre backhaul, with the microwave link acting as a backup.

04-06-2015, 13:55	#1
InfamousTeal Forum Member Join Date: Oct 2014 Location: Northern Ireland Posts: 303	Microwave Backhaul Hi everyone, thought I'd make a new thread for this rather than asking on the end of Three 4G thread for example, cos it applies to all networks really. I'm interested in the whole Backhaul section of networks, particularly microwave atm. Here in N Ireland, the MBNL masts all have at least 1 /2 microwave dishes on them, I'm guessing fibre is going in somewhere, and practically every single mast around here is "looking at" each other. Planning permission shows which masts are looking at who. (there aren't many masts so it's not hard!) I was wondering, because of this daisy-chain like setup, if a mast goes down, say for maintenance, upgrades, just engineers changing something for an hour, does that knock out the microwave? Surely if the power is off, it would? Which.. Would mean so many more masts would suddenly lose their Backhaul. I'm trying to work out which mast is getting fibre around here, by mapping the microwave paths of each one. But I know for sure that my local mast went completely down for maintenance last week, for a day, and it's part of a daisy-chain of microwaves, spanning about 20 miles west. So, did half of the north west suddenly lose Backhaul? Or , does the microwave transmitter have a different power source? Sorry for the waffling

04-06-2015, 16:48	#2
wrexham103.4 Forum Member Join Date: Oct 2009 Posts: 3,140	They daisy chain around here too, right pain in the arse when u don't have any signal for a 15 mile radius. Vodafone and O2 seem to be ok when power is lost

05-06-2015, 12:20	#3
InfamousTeal Forum Member Join Date: Oct 2014 Location: Northern Ireland Posts: 303	So does anyone know if powering off a mast knocks out microwave? I've found one near me that's "looking at" at least 6 different towers

05-06-2015, 14:54	#4
DevonBloke Forum Member Join Date: Apr 2011 Location: Totnes, Devon Posts: 6,694	I don't know but my guess would be it depends on the kit and how it's set up. I would imagine the whole backhaul part that the MW dishes terminate in were separate to the the actual 2G/3G/4G rack unit. The cellular modules would plug into them via optical or Ethernet surely? So you could power off the cellular without affecting the MW link. Just a guess but seems sensible.

05-06-2015, 15:05	#5
lost boy Forum Member Join Date: Sep 2005 Location: Norfolkland Posts: 1,787	Quote: Originally Posted by InfamousTeal So does anyone know if powering off a mast knocks out microwave? I've found one near me that's "looking at" at least 6 different towers I'm no expert, but I'd say it would depend on if there's any redundancy or not. I know T-Mobile, back in the day, used to have a LONG daisy chain going on here, which due to overloading and other technical issues at the 'hub' (for want of a better word) of the chain means that the whole chain used to have no end of problems. Eventually they gave in and erected a new 'hub' more locally, and most of the problems went away. To be honest, the only thing that completely knocks out the T-Mobile half of EE here now is a power outage.

05-06-2015, 18:27	#6
Icaraa Forum Member Join Date: Feb 2013 Posts: 1,732	O2 uses BT for backhaul whereas the others use Virgin Media or Vodafone (C&W) fibre instead where they can. They probably daisy chain and then get onto one of those networks to avoid BT fibre charges.

05-06-2015, 20:07	#7
moox Forum Member Join Date: Oct 2004 Posts: 14,645	Quote: Originally Posted by DevonBloke I don't know but my guess would be it depends on the kit and how it's set up. I would imagine the whole backhaul part that the MW dishes terminate in were separate to the the actual 2G/3G/4G rack unit. The cellular modules would plug into them via optical or Ethernet surely? So you could power off the cellular without affecting the MW link. Just a guess but seems sensible. There's a document flying around from MBNL showing how to connect and configure NEC Pasolink radios for EE/3, so that would confirm it (it would also make logistical sense to order the 3G/4G base stations with a standard configuration and use separate units for whatever backhaul was available)

05-06-2015, 21:20	#8
Redcoat Forum Member Join Date: Jun 2001 Location: The wilds of West Tyrone Posts: 2,122	Some sites MBNL use in Northern Ireland can be quite remote to access and/or not be close to fibre links. Nearly all the ex-Orange sites that were upgraded had included larger microwave aerials to be installed presumably to allow better wireless links with faster throughput and reliability. I've generally assumed in cases like this for MBNL in rural areas, there is a relationship between cell sites similar to that for the UHF DTT network, where there are "main" mother cell sites that are connected to fat fibre connections in towns on reasonably high locations, with cell sites in more isolated areas where fibre connections can't be reached without excessive cost are connected to the main cell site via microwave link in a similar way a UHF TV relay station is connected to a main station for its feed to broadcast, with in most cases this microwave link to the mother station being only one link but in some cases two and in extreme cases three or even more. There will be plenty of instances though that a microwave aerial will be present even if the cell site is linked to fibre backhaul, with the microwave link acting as a backup.

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Microwave Backhaul