4G TV interference: Up to a million homes 'need filters'

The 4G signal will be used by the next generation of smartphones and tablets

Almost a million UK homes will need to have filters installed to prevent TV interference from 4G mobile signals - at a cost of £108m.

A smaller number of homes - about 10,000 - will need to switch to satellite or cable TV services in order to avoid degraded picture quality.

Homes that cannot receive these alternative platforms will receive up to £10,000 each to "find a solution".

Costs will be met by the winner of a spectrum auction later this year.

Consultations are currently being held into how spectrum - part of which is used by analogue television - will be offered to mobile operators once airwaves are freed up by the switch to digital.

These airwaves are crucial to mobile operators to create next-generation mobile services.

The winning bidder, or bidders, will be required to pay for the costs of making sure viewers of digital terrestrial television (DTT) will not be affected by the changes.

Unwanted noise

In a consultation document released in August last year, media regulator Ofcom estimated that about 760,000 homes could be affected.

However, the Department for Culture, Media and Sport (DCMS) told the BBC that further research had suggested that number was likely to be closer to 900,000.

Homes falling within a certain range of transmitter towers will automatically have a filter issued, while a helpline will be set up to deal with interference cases outside of the predicted areas.

The filter, which is fitted to a digital TV box, blocks out unwanted noise from the 4G signal.

It can be fitted without the help of an engineer - but over-75s and disabled people will be given assistance if needed.

The DCMS said that in a very small number of homes, the filters would not be sufficient. A platform change - to satellite or cable - will be required, the cost of which will also be covered by the mobile operator.

It is estimated that about 10,000 homes may need to take this measure.

It is also predicted that about 500 homes affected by interference will be unable to receive satellite or cable services.

In these cases, expected to be in rural areas, up to £10,000 per household will be provided to fund alternative solutions to receiving television - such as having fibre cabling installed.

The DCMS said it predicted that small groups of affected houses would be able to pool their funding in order to pay for bigger investments like additional relay transmitters.

'Disruptive'

Without the preventative measures, television pictures would become unclear and fragmented, warned Saverio Romeo, an industry analyst from Frost & Sullivan.

"The LTE [Long Term Evolution] spectrum, particularly on 800Mhz, overlaps part of the DTT spectrum," he said.

Culture Minister Ed Vaizey said 4G technology would give the UK an economic boost

"The closer you are to a base station, the more disruptive the interference."

He said that in addition to the £10,000 fund for the severely disrupted homes, education should be provided in order to help people understand what options were available.

"If you give £10,000 to a lady in Cumbria and say: 'You need to fix it' - I don't think it's enough.

"You need to help people understand new technologies. It's not enough to give subsidies."

A spokesman for the DCMS said additional advice would be given to those receiving the financial help.

Culture Minister Ed Vaizey said adoption of 4G would provide a boost to the UK's digital economy.

"Next-generation mobile services are essential for economic growth. They will bring an estimated benefit of £2-3bn to the UK economy.

"There will be some interference when 4G services are rolled out but we will have the solutions in place to eliminate the disruption to television viewers."