menuMENU    UK Free TV logo Archive (2002-)

 

 

Click to see updates

How do I know if the 4G broadband will overload my Freeview?

During 2013, some of the frequencies that were used for television before the Digital Switchover will be auctioned off and used to provide 4th generation (4G) mobile broadband. Many homes will need to fit a filter, and a small few will have to switch (for free) to Freesat. Knowing in advance where these homes are is a complicated matter.

During 2013, some of the frequencies that were used for televis
published on UK Free TV

Back in June 2011, we looked at how Ofcom moves to protect Freeview interference from 4G mobile .

Since then, the television Digital Switchover has been finished and 4th generation (4G) mobile broadband services - also known as Long Term Evoluition (LTE) have launched all over the world, including a service from Everything Everywhere (EE) in the UK.

To understand why and how these 4G broadband services will cause problems during 2013, you need to take into consideration a number of technical factors.

Understanding the radio spectrum

The Radio spectrum is the name given to the frequencies of the electromagnetic spectrum that can be usefully used to transmit radio, television and data services.

The top bar on the diagram below (or download) shows a selection of the services used in the UK, with old-fashioned long-wave radio, then medium-wave radio, though FM radio, the digital DAB radio services up to those used for television broadcasting. (See here for a really complex chart).

Radio Spectrum for TV, radio, DAB and mobile phones

The highest frequencies on the diagram, the "ultra high frequencies" (or UHF) band is shown enlarged as the lower purple bar. In this range we can see TV "channels C21 to C60" (blue), second- and third- generation mobile phones (2G orange, 3G pink) and the location for the 4G services.

It is important to note that some of the 2G capacity in the "1800MHz" range has already been converted to 4G operation by Everything Everywhere (EE). The other two yellow boxes show the "800MHz" (to the left) "2.6GHz" (on the right).

For the purpose of Freeview reception, only the 800MHz range need be considered. The other two ranges will not cause Freeview problems.

Protecting Freeview receivers against overload

As we have seen already - Freeview signals: too much of a good thing is bad for you - Freeview boxes are designed to protect themselves against signal overloads. When they do this they close down and people often incorrectly diagnose the problem as being "no signal" when there is too much.

The problem that has to be solved as the 4G services launch, is that the new mobile broadband signals can cause overloads onto the frequencies that are being used for Freeview.

Too much signal One particular problem is that a very common type of Freeview signal decoder, a superheterodyne receivers are sensitive to signals being present nine channels (72MHz) away.

In addition to overloads, 4G may also cause Signal-Interference Noise Ratio degradation, where reception breaks down because the receiver can no longer decode the digital information in the transmission.

Knowing who will win the 4G auction

Too much signalUntil the 4G auction takes place, no one will know which company has the right to use the 800MHz channels for mobile devices. The following companies have qualified to bid:

  • Everything Everywhere Limited (UK)
  • HKT (UK) Company Limited (a subsidiary of PCCW Limited)
  • Hutchison 3G UK Limited
  • MLL Telecom Ltd
  • Niche Spectrum Ventures Limited (a subsidiary of BT Group plc)
  • Telefonica UK Limited
  • Vodafone Limited


Viewing high power television and using low power mobiles

Using the 'Sitefinder' Mobile Phone Base Station Database you can compare the locations of existing mobile phone "masts" with those used for Freeview Transmitters. Here is an example from Brighton and Hove, where a medium-sized single mast (Whitehawk Hill) can cover a whole city, but where hundreds of mobile phone base-stations cover a many smaller-by-comparison areas.

Example of different coverage areas between 4G and Freeview

This illustrates two points. Firstly, that Freeview broadcasts are high powered and one-to-many - mobile devices are low power and peer-to-peer. The mast your TV signal comes from may be miles, sometimes tens or miles away, for your mobile perhaps only meters away.

The second point is that if an existing 2G/3G mobile supplier wins a 800MHz 4G slot, they will wish to use their existing "phone mast" locations (especially the 900MHz ones) as this would be most economical for them. Until the action winners emerge, and then plan their network, only idle speculation about possible interference can be made.

Using the TV frequencies for 4G masts and phones

Research (see here) shows that a 4G mast in relative close proximity, or a mobile 4G handset closer than a meter to an unfiltered Freeview box will cause overloading on many tested devices. The following diagram shows the relationship between the 4G use and the old TV channel designations.

Usage by 4G of old TV transmission channels

Those Freeview transmitters that use channels above C52 are most likely to have receivers that get overloaded by the use of 4G signals in the 800MHz area. FDD is Frequency-division duplexing - the transmitter and receiver operate at different carrier frequencies.

Interpreting the aerial and mast locations

Once the proposed mast locations for 4G services are known, it will then be possible to predict which homes will need to fit the special filters in areas where Freeview uses the higher channel numbers (the C52 to C60 range).

The TV aerial on your rooftop, 4G mast, Freeview transmitter

If you then have a rooftop aerial without a signal amplifier, to get an overload you will need the 4G mast to be in the line-of-sight between your Freeview transmitter and the aerial, or possibly "directly behind" the aerial.

If you then have a rooftop aerial and an amplifier, or perhaps have lower-grade cables, you are likely to need to protect from a 4G overload if the phone mast is close to your rooftop aerial.

Finding transmitters that use the higher range frequencies

Some powerful transmitters and many relays use the high frequencies: Sudbury, Oxford, Belmont, Winter Hill, Tacolneston, Pontop Pike, Mendip, Emley Moor, Clermont Carn, Truskmore and Maghera.

Click below to find out the transmitters in with high frequency allocations:



Protecting Freeview boxes and sets, cables, amplifiers from 4G devices

Again in areas where Freeview uses the higher channel numbers (C52 and above) you may have to protect your Freeview devices from signals from a 4G handset (such as mobile phone, tablet, or USB "dongle").

Your set-top box or Freeview TV, Your aerial cables, 4G mobile device

This may, once again, require the fitting of a special filter, or the upgrading of the "fly leads" used to connect your aerial to the set top box or TV. This may be a particular problem if you have used an indoor aerial or signal amplifier.

Help with TV/radio stations?
Can I receive British Eurosport for free?1
Can I receive DAB radio too?2
Can I get E4 with this service?3
Is sky|one going on Freeview?4
Can I watch for free Financial channels such as CNBC or Bloomberg?5
In this section
Ofcom announces 700 MHz clearance schedule 2017-201
When will I get a new Freeview aerial because of even more mobile broadband? 2
Do not forget that 4G starting soon in 20 cities and towns really soon3
Using UHF channels C61 to C69? Time to retune4
Two final Freeview retunes in Scotland on 24 and 31 July 20135
800MHz band cleared by Digital UK - ready for nationwide 4G use6

Comments
Thursday, 4 April 2013
I
ian from notts
sentiment_satisfiedSilver

7:53 AM
Nottingham

Ian T- having a quick look at "Z-Wave" and i would ASSUME you may have some problems?
a simple reset to another rf frequency for your equipment should suffice, but,
it may well be that the strength of the Z-Wave could stop 4G working in your house ! (generally the opposite of your worries).
the only trouble you should have will be from any wireless networking in use as the hard cabling products will be shielded.
interesting mate

link to this comment
ian from notts's 253 posts GB
P
paul feetenby
11:13 PM
Birkenhead

hi is there a fault with the winter hill transmitter as i have poor signal quality on my freeview tv. i live in birkenhead merseyside

link to this comment
paul feetenby's 2 posts GB
Friday, 5 April 2013
D
Di Staley
7:13 PM
Market Rasen

Hi... We bought a new Humax DTR1010 yesterday .... It is brilliant but keeps telling us that there is a weak signal and there is a lot of pixelation. We have also had a message to say that we may have to re-tune after 10 April. After investigation I see that Winter Hill is doing 'something' on that date! We are in North Lincolnshire...can anyone confirm if our signal/pixelation problem will be resolved after the 10 April....or should we return our PVR.

link to this comment
Di Staley's 1 post GB
M
Michael
sentiment_satisfiedGold

7:51 PM

Di Staley: You're very unlikely to be getting Winter Hill where you are, the messages are likely from Emley Moor, of which a couple of its relays are changing frequencies on the 10th.

I would check the manual retune/signal strength option in the menu to see which UHF channel you are tuned in to for channels 1, 3, 10, 11, 15 and 101 - you may be tuned in to a poorer signal than what is available.

link to this comment
Michael's 358 posts GB
Dave Lindsay
sentiment_very_satisfiedPlatinum

8:26 PM

Di Stanley: Emley Moor is definately broadcasting messages and these appear on BBC One. I don't know whether these also appear on Belmont which is a different region.

link to this comment
Dave Lindsay's 5,724 posts GB
Saturday, 6 April 2013
R
Richard
sentiment_satisfiedBronze

7:14 AM

My house is approx 30yds from O2 mast. Is it inevitable that we will have a problem with our freeview signal? I do not have any aerial amplifiers fitted.

link to this comment
Richard's 28 posts GB
Monday, 8 April 2013
I
ian from notts
sentiment_satisfiedSilver

7:32 AM
Nottingham

Richard- it also depends on which transmitter you are aligned to, which way your aerial faces, where you live and if the O2 mast is to be used for 4G

link to this comment
ian from notts's 253 posts GB
Saturday, 13 April 2013
J
John
5:12 PM

Hello,

Since 4G was introduced the freeview signal for ITV1, Channel 4,5, ITV2, but not ITV3 have been reduced in strength.

My P.C. is W140BG.

Could 4G be the 'cause'?

link to this comment
John's 1 post GB
Monday, 15 April 2013
I
ian from notts
sentiment_satisfiedSilver

8:57 AM
Nottingham

John- as far as i'm aware 4G hasn't yet been introduced anywhere ?

link to this comment
ian from notts's 253 posts GB
Tuesday, 16 April 2013
I
IDP
11:36 PM
Crewe

since the winter Hill retune on APRIL 10TH the channels: itv/channel 4/channel 5 have vanished. Four televisions following several retunes now only list channels 1,2,7,9 onwards.
Any suggestions how to get them back?

link to this comment
IDP's 1 post GB
Select more comments

Your comment please
Please post a question, answer or commentUK Free TV is here to help people. If you are rude or disrespectful all of your posts will be deleted and you will be banned.







Privacy policy: UK Free Privacy policy.