BY AHMED NADEEM

Spectrum is a limited and an indispensable resource that is needed to broadcast TV and radio services . Broadcasters need to ensure that adequate radio spectrum is allocated to them , and that it is carefully managed and efficiently used for future applications .

The UHF broadcasting spectrum ( originally 470-862MHz ), widely used for broadcasting services around the world , has come under substantial pressure in recent years specifically for identification for use by IMT ( International Mobile Telecommunication ). In past World Radiocommunication Conferences ( WRC ), parts of the lower UHF band have been re- allocated to mobile , and sub sequently there has been clearance in many countries of broadcasting from these bands to accommodate IMT systems .

Reduction of these spectrum bands has placed restrictions and constraints on the roll-out and further development of TV broadcasting

services in many countries , despite continued demand for TV services by viewers .

One question is : Why do broadcasters need this much spectrum ? This question is actually more relevant now than before due to the developments taking place in the industry . The case is further prominent in Asia-Pacific , where to date only five countries have completed the analogue switch-off . The analogue-to-digital migration process , to begin with , requires more spectrum to be available , as both analogue and digital signals need to be made available simultaneously in the initial stages — referred to as a simulcast period .

The reason is that the analogue signal cannot be switched off until the digital signal is made available in a similar manner and the public is ready to receive the digital signal through acquiring the necessary set-top boxes or new TV sets . This simulcast period may vary between two and five years , or in some countries even more , depending

on the size of country and scope of implementation . There are a few countries in Asia-Pacific looking at completing the process in the next one to two years but the majority of them are still in the planning stages and could take more than five years until it is completed .

The good news is that collective efforts within the ABU and its sister unions through the World Broadcasting Union ’ s Technical Committee ( WBU-TC ), with support from our members , resulted in a favourable outcome during the previous WRC in 2015 .

WRC-15 took the decision that UHF spectrum band , mainly used by broadcast services such as digital terrestrial TV and radio microphones , is very important for broadcasting services . It was agreed that there would be no region-wide IMT identification in this band and this added security will enable many countries to continue their digital switchover process , without the risk of an impending change in use of the spectrum , possibly

until WRC-23 .

As mentioned above , this leaves just about five years before WRC-23 arrives , and given how the process works , broadcasters are going to come under a lot of pressure come this time . Therefore , it is imperative that broadcasters take the early initiative to discuss this matter with their regulators and their respective governments to secure the necessary spectrum for the process of digitisation and future developments of their services .

Broadcasters and relevant stakeholders need to work together to voice out their concerns on such allocations of spectrum from the UHF broadcasting band to mobile and other services .

Ahmed Nadeem is director , technology and innovation , Asia-Pacific Broadcasting Union ( ABU ).