Digital Broadcast: reducing transmission network energy cost and environmental impact

The worldwide introduction of digital terrestrial TV systems will lead to significant numbers of new transmitters being installed over the next few years. With the recent rise in energy prices, and increasing concerns over environmental impact, it is important that these new transmitters are as energy-efficient as possible.

Operational costs have always been a key issue for broadcasters, and a substantial part of these costs is due to the electricity required to run the transmitters (typically accounting for over 75% of total electricity usage).

Aside from the cost argument for increased transmitter efficiency, there is also a strong desire from the broadcasters to improve their environmental or 'green' credentials and to be seen to be responsible in their use of energy.

Current digital TV transmitters are very power-inefficient due to the use of linear RF power amplifiers (PAs), which typically account for half of the total power used by a transmitter.