Ofcom is proposing to re-organise and upgrade DTT multiplexes in the UK in an effort to shoehorn in other services.

Speaking at Broadcast Live and Video Forum today, Ofcom's Greg Bensberg said that a move to use compression standards DVB-T2 and MPEG4 and a re-organisation of which channels appear on certain multiplexes would leave a space that could be used by public service broadcasters to provide HD services.

However, although HD is an option for the available space, nothing is guaranteed. Bensberg said: “We have to ask is HD the best thing to occupy the available capacity on a cleared multiplex? We have nothing against HD but there are other uses of spectrum that have an equal say.”

The proposed re-organisation would see certain current DTT channels - including ones from ITV and Channel 4 - moved from a universal multiplex to a national one, which would impact on that channel's country wide penetration.

Bensberg said that “existing services would be protected” but some channels would have to move to a “non universal service.” This would mean that some viewers won't get all the channels while others will get HD ones.

If the proposals are approved there could be space for three HD channels by 2009. All the PSB broadcasters will be invited to pitch ideas for the available spectrum. There would no financial bidding involved.