| 22 Jun 2024
DRM best digital radio system as it utilizes present technologies and uses lesser spectrum: Pal

NEW DELHI: Even as the Telecom Regulatory Authority of India has scheduled an open house discussion on digital radio broadcasting based on a paper issued by it on 10 July this year, the Digital Radio Mondiale has strongly urged the government to encourage the efforts of digitising the All India Radio medium wave and shortwave transmissions using the DRM digital standard.

In its response to the consultation paper, the Indian wing of DRM Consortium has said the government should also facilitate full utilisation and announcement of a roadmap for the complete switchover of radio broadcasting, including the private FM and Community Radio Stations, to digital radio in India.

DRM Consortium – India head Yogendra Pal in his detailed response said that the existing analogue transmission equipment (both AM and FM) can be upgraded to DRM operation, reducing initial setup cost (depending on hardware manufacturer/model)

He said when upgrading an analogue transmitter to full-digital operation, the same or more coverage can be achieved, while significantly reducing transmission power, enabling green and cost-optimized broadcast networks for the future.

DRM allows a flexible trade-off between transmission power, coverage requirements and content capacity, to always enable the most economic operation for any given coverage scenario.

The consortium strongly feels that there is an urgent need to frame a roadmap for digital radio broadcasting in all bands. This includes the FM band and private FM broadcasters too.

There is no doubt that FM analogue radio is a very good standard. It provides stereo audio broadcasting, it is a robust and well established. There are millions of FM receivers and there is demand for the expansion of private FM broadcasting and community radio stations.

Referring to the usage of FM spectrum, he said available FM spectrum is not sufficient to meet the full demand by Indian broadcasters and the public. FM Band is from 88MHz to 108 MHz that is, 20 MHz bandwidth. One single FM channel needs 200 kHz bandwidth. So, theoretically, there can be a maximum 100 FM channels in the full FM band.  But, unfortunately, neither is a full band available for broadcasting nor can two adjacent channels be broadcast without some guard band. The same FM frequency can be repeated only after about 400 to 600 km, or with a frequency separation of several hundred kHz. Although FM broadcasting is popular, the possibilities for extending the FM coverage in its band of 88-108 MHz remain limited.

In addition to stereo audio content, analogue FM enables the broadcast of a very low bit data channel. Analogue FM, an early 20th century technology, is a successful standard but, in truth, it has reached its spectrum, coverage and improvement limits. It might be a good solution for now but not a strategic choice for the future, with increasing expectations of the public regarding audio quality, service diversity, and added-value services tying radio in with modern media consumption. This, in time, has to be and will be accompanied and, eventually, replaced by the digital, compressed, enhanced features of digital radio. Using only 50 per cent spectrum, digital (DRM) in VHF band is able to offer multiple services on a single frequency, 5.1 surround sound quality and a number of value-added services along with significant transmission power savings.

So keeping in tune with the vision of the new government, it is time to plan digital broadcasting in VHF (FM) band also using the already adopted DRM standard and thus benefitting from the following salient features:

1.Equally supporting all terrestrial radio broadcasting bands, including MW, SW and VHF bands (with the FM band II included alongside band I and band III). The audio quality offered by DRM is equally excellent on all the transmission bands: MW, SW or VHF.

2.Robust signal unaffected by noise, fading or other forms and interference in all bands.

3.Clear and powerful sound quality with facility for stereo and 5.1 surrounds.

4.More audio content and choice: Up to three audio programmes and one data channel on one frequency.

5.Extra multimedia content: Digital radio listeners can get multimedia content including audio, text, images and in future even small-scale video, such as:

a.Text messages in multiple languages.

b.Journaline – advanced text-based information service supporting all classes of receivers, providing anytime-news for quick look-up on the receiver’s screen; interactivity and geo-awareness allowing targeted advertising.

c.Electronic Programme Guide (EPG), showing what’s up now and next; search for programmes and schedule recordings.

d.Slideshow programme accompanying images and animation.

e.Traffic information.

Due to the inherent advantages of digital broadcasting, broadcasters the world over are adopting high quality digital delivery systems with TV leading the way. Mandatory digitisation of cable TV networks in India is the example. Digitisation of the terrestrial radio broadcasting is also inevitable. In fact, the Planning Commission in 2006 had given timelines for the switch-off of analogue radio and terrestrial TV transmissions in India as well. AIR and DD started taking action in this direction.

AIR has chosen the ITU endorsed DRM standard, with all technical specifications published and freely accessible to the Indian industry for the digitisation of its terrestrial radio networks. But the task of migrating AIR’s terrestrial broadcast services today is still incomplete. Therefore, it is essential that the full potential of DRM digital radio in MW and SW is soon utilised by configuring the best possible audio quality, finalizing the service selection for each location, and adding value-added services such as Journaline text and EWF (DRM’s Emergency Warning Functionality), and a roadmap is provided for the complete switchover of radio broadcasting, including private FM and community radio Stations, to DRM digital in India. This task, demanded to be carried out immediately by the Ministry of Information and Broadcasting will require a department-spanning stringent management that also reaches out to the public and the Indian receiver and automotive industry.

DRM is the newest and most technologically advanced global digital radio standard. It is internationally standardized by ITU and ETSI for digitising terrestrial radio broadcasts in all frequency bands (both AM and FM bands). It is capable of fully serving India’s needs, with all its diverse coverage demands, at low energy costs and with rich and freely accessible features set. DRM is the digital radio standard in direct succession to its analogue predecessor technologies AM and FM. It matches existing ITU-conforming channelization and frequency regulations and maintains full ownership of the technology, its deployment, product development and roll-out in the hands of the Government and industry.

In January 2017, then I and B Minister M Venkaiah Naidu had lauded the national public broadcaster All India Radio (AIR) under Prasar Bharati for having successfully completed Phase I of the national digital radio roll-out. AIR has completed the installation of the nationwide network of 37 powerful medium and shortwave transmitters operating in simulcast or pure DRM mode, resulting from a significant national investment.

Phase II inaugurated by him is aimed at finalizing the selection of programmes per region, the implementation of all DRM features and the improvement of the content quality provided by those transmitters, will ultimately result in the official launch of DRM digital radio services by AIR to listeners.

Though DRM has not officially launched yet as a service to the public, given that Phase II of the national roll-out of DRM digital radio by AIR has just started a few months ago, the industry is already showing their commitment and support to be in the market with products once AIR’s DRM services will officially launch.

Probably the most important factor for establishing modern radio listening habits is the support for AIR’s digital radio roll-out demonstrated by the automotive industry. Mahindra & Mahindra demonstrated their line-fit DRM receiver in car models launched not long ago. Also, Maruti Suzuki has launched cars with DRM line-fit receivers. In early 2017, Hyundai joined by announcing two new car models with native DRM support. By late summer 2017, this has grown to a total of five models ranging from entry-level products to high-end cars – all radio sets with DRM functionality included, at no extra cost.  Many major automotive brands have scheduled the launch of DRM capable car receivers for India in the next two years, almost all of them based on chipsets developed and produced in India.

Today India is in a leading position worldwide by rolling out digital radio on a national level using the DRM standard, with great cooperation and product export opportunities into countries all over Asia-Pacific and beyond. Currently, countries such as Pakistan (for both local coverage in the FM band and large-area coverage in the AM bands), Indonesia, South and Southern Africa, and many more are in the process of adopting and/or rolling-out DRM for national coverage. In addition, a huge portion of the world’s population is already covered by DRM transmissions on international shortwave.

In the past, several digital radio standards have been thoroughly tested and reviewed by Indian authorities, and DRM was tested, identified and confirmed to be the best-suited option for India’s radio digitization needs (incl. the detailed “Report of the Expert Committee on Prasar Bharati” under Dr. Sam Pitroda). DRM is the most advanced standard to-date, incorporating the experiences and lessons learned from previous approaches. It utilizes the latest audio codec “MPEG xHE-AAC”, which ensures the highest possible audio quality even for very robust transmission signals.

From a cost and business perspective, DRM transmission equipment and receivers are easy to calculate and cheap to produce by manufacturers: Firstly, given that DRM is an open standard, no ‘license’ (or ‘permission to use proprietary technology’) is required.

All aspects of the DRM technology are published and freely accessible, and no single company or entity owns the DRM technology. There is no use-fee or revenue sharing approaches for the DRM technology – neither for broadcasters nor for listeners.

DRM can carry up to four services per transmission as a flexible mixture of data and (up to three) audio services

DRM ensures clear sound with the latest MPEG audio codec technology xHE-AAC, enabling multiple stereo programmes in FM quality on a single MW transmission, stereo services over SW, and multiple stereos or even 5.1 surround services in the FM band

Thanks to the Journaline advanced text application, DRM makes the broadcast’s rich textual information treasure with news, sports updates and much more, in the past only available on the broadcaster’s web page, available to all listeners right on the radio sets as part of the radio service – free to air, without the need to pay for Internet access, and simultaneously in a multitude of languages with every DRM transmission.

DRM allows the broadcaster to transmit multiple audio and data services in a single transmission, without any extra cost or the need to sign license contracts.

DRM allows the broadcaster to transmit special or even B2B data applications such as traffic services, without extra cost or the need to sign license contracts.

The ITU approved DRM standard provides identical functionality on all broadcast bands from large-area coverage in the AM bands to local/regional coverage in the FM band, ensuring optimized and low-cost receiver design

DRM is the only digital radio ITU standard to also cover national and international shortwave transmissions

DRM in VHF bands uses less spectrum than current stereo FM broadcasts, whilst additionally deriving the potential benefits of increased robustness, reduced transmission power, increased coverage or additional services: While analogue FM transmissions carry a single audio service within a bandwidth of at least 200 kHz, a DRM digital radio signal carries up to three audio services along with value-added services in better-than-FM quality within only 96 kHz bandwidth for the on-air signal.

It helps in automatically switch for disaster and emergency warnings in case of impending disasters. In large areas, automatically presenting the audio message, while providing detailed information on the screen in all relevant languages simultaneously. Great potential to become the surest and widest means of alerting the population to emergencies.

DRM supports multi- and single-frequency network operation (MFN/SFN). SFN operation allows multiple transmitters to cover a common area on a single frequency, which allows for new and more efficient network designs by extending coverage areas with additional synchronized transmitters as required and solving typical network problems such as signal outages due to shadowing by using small-power gap-filler transmitters. In contrast, analogue FM services required additional individual FM frequencies for each additional transmitter in the network, as otherwise the signal in the overlapping coverage areas would be destroyed.

DRM supports the automatic hand-over to other frequencies and even other networks (AFS – Automatic Frequency Checking & Switching) once the receiver leaves the coverage area of the currently tuned transmission, and keeps the selected service tuned as long as possible while on the move without the needs for any user interaction.

DRM is fully compliant with the frequency allocations of the current FM and its analogue transmissions. And using DRM’s simulcast operation mode, it guarantees for a smooth transition from analogue FM services to future DRM-only operation by initially inserting the new digital services in the existing FM band without affecting the already existing analogue transmissions.

The extension of the license (which should be free, or at nominal cost) would be dependent on the broadcaster getting digital services on the air (within a specified period of i.e. 1or 2 years). This is realistic as the digital signal in DRM is only 100 kHz wide and can be contained within the 800 kHz FM allocation, or it can be placed independently wherever there is a gap in the spectrum (and not necessarily next to the FM frequency).

DRM suggested a smooth and non-disruptive migration from analogue-only FM to future digital-only DRM transmissions in the FM band over a period of time and with full protection for the FM licenses issued to broadcasters as part of Phase III and previously. During this transition period, DRM’s simulcasting capabilities and flexibility in terms of using gaps in the FM spectrum while peacefully co-existing with analogue FM services (and, thereby, greatly extending the overall capacity of the FM band) are key success factors.

DRM has recommended the following 'very flexible' approach:

1.Complete the allocation of Phase III of private FM auctions (for 15 years permission as per the existing policy) as early as possible. And as an incentive for going digital, allocate an additional frequency (absolutely free for, say, 5 years) to each of the successful bidders in VHF band for DRM services with the condition to implement the DRM digital services within a definite period of, say, 1 or 2 years. Failing this initial setup term or failing to continuously operate the additional digital transmission at any time during the proposed 5 year period, the allocation of the additional frequency for DRM digital should be deemed to be cancelled and available for separate auctioning to third parties.

2.Allocate an additional frequency (absolutely free for, say, 5 years) to each of the existing FM broadcasters in VHF band for DRM services on the condition to implement the DRM digital services within, say, 1 or 2 years period. Failing this initial setup term or failing to continuously operate the additional digital transmission at any time during the special license grant (of say 5 years), the allocation of the additional frequency for DRM digital should be deemed to be cancelled and available for separate auctioning to third parties.

3.Irrespective of whether or not the licensee chooses to use the free additional digital-only, licensed FM broadcasters may be permitted at any time during their license term to obtain permission to migrate their main analogue FM frequency to DRM on the existing terms and conditions.

4.Announce that no analogue radio transmissions (including analogue FM license extensions) would be allowed after 15 years or at the end of the current FM license terms, respectively, and develop a policy to renew the licenses of the existing private FM players, as and when these expire, for the maximum period of 15 years from now keeping in view the time for analogue transmissions proposed to be allowed to the successful bidders of Phase III.

5.Within the period of 5 years, develop and announce plans for the allocation of frequencies for DRM digital transmissions in the VHF band for AIR, private FM and Community Radio Stations. Also, keep the requirements in view of the All India Highway Advisory Service in DRM digital proposed to be started by the National Highway Authority of India (NHAI).

6.AIR should also develop and announce its plan for DRM digital implementation in VHF bands, as well as the remaining analogue MW & SW transmitters, as per the above proposed 15-years switchover period from now.

7.Develop and announce a policy for DRM digital implementation for Community Radio stations also along similar lines.