Europe approves second DAB multimedia standard

A new standard for carrying multimedia traffic on the DAB digital radio signal has been approved by the European trade body Etsi.

DAB (Digital Audio Broadcast) transmissions have been used almost exclusively for audio in Britain, but there is growing interest in using the same signal, and possibly the same transmitting infrastructure, to send TV and other multimedia to mobile devices such as smartphones.

The new DAB-IP standard was welcomed by BT, which plans to use it for a mobile broadcasting service called BT-Movio. The original DAB standard, being digital, is capable of transmitting any kind of data, but it lacked the robustness required for multimedia.

Nigel Robson, a spokesman for Radioscape, one of Britain's two big DAB technology specialists, explained: "It does not matter that much if you drop a couple of bits in audio, but if you are tramsmitting TV a dropped frame can be very noticeable."

Korea has another multimedia DAB standard called DMB. Robson said the two standards would not cause any trouble at Radioscape because it uses software-defined radio, in conjunction with a general-purpose signal processor, and can resolve any differences by tweaking the code.

Rival Frontier Silicon , which designs dedicated DAB chips, could not comment immediately.

DAB stations are currently very constrained in the bandwidth they can give to multimedia broadcasts. But DAB multimedia is sure to be one technology competing for the new spectrum that will be freed up over the next five years, mostly by the switchover from analogue to digital broadcasting.

Some companies favour rival DVB-H, a variant of the digital signal used for terrestrial Freeview broadcasts. But in the UK DAB has a headstart because much infrastructure is already in place.