Digital radio gets some bandwidth

Digital audio broadcasting (DAB) in the country appears set to move beyond satellite radio WorldSpace, the only platform it is currently available on.

The new national frequency allocation plan, which has just been chalked out by the government, has a provision for DAB.

According to the plan, which is effective from this month, introduction of DAB may be considered in the 174-230 MHz frequency band in the four metros to start with and on a case-by-case basis in other parts of the country subsequently.

DAB refers to audio broadcasting where analogue audio is converted into a digital signal and transmitted on the AM or FM frequency range. This results in compact disc-like audio quality. The technology was first introduced in the UK in 1995, and is now present across Europe.

All India Radio is learnt to be keen to bring DAB into the country. Telephony and mobile TV are among the other new areas the latest frequency allocation plan has made room for.

For instance, it talks of rural communications. “Requirement of rural communications may be considered for coordination in the frequency band 368-380 MHz on a case-by-case basis.”

Also, the plan incorporates frequency bands for remote cardiac monitoring wireless medical devices. In fact, the plan has made use of very low power remote cardiac monitoring wireless medical devices, medical implant communication/ telemetry systems and other medical wireless devices in the frequency band 402-405 MHz exempt from licensing requirements.

It also mentions new areas like digital seismic telemetry, anti-collision device applications, train control, mobile train radio systems and deep space research operations.

Within telephony, too, the plan talks of newer areas. For example, it mentions the requirement of micro-cellular wireless access systems for telecom services. This system would be considered on the frequency band of 1,880-1,990 MHz on a case-by-case basis.

In his introductory remark on the new frequency allocation plan, telecom secretary Siddhartha Behura has said that “With the emergence of new technologies and with astounding growth of telecom services all over the world, the spectrum management process has become extremely complex and intricate. It is necessary that all spectrum and orbit users, whether government or private, work in the spirit of mutual understanding and cooperation and utilise these resources in an optimal manner with self-discipline.”

Interestingly, the national frequency allocation plan makes a reference to the “harmful interference” from wireless access systems. It says appropriate measures of incorporating filters in the wireless access systems for telecom services shall be taken.

Also, appropriate measures for putting filters in cellular based networks for blocking signals leaking through the extended cellular frequency bands shall be taken, the plan document adds.