Friday 28 August 2020

DRM for FM Bands - An article by Sh. Y. Pal former ADG, AIR


All India Radio (AIR) has adopted the Digital Radio Mondiale (DRM) standard for digital terrestrial radio broadcasting in MW and SW bands. Thirty-eight high-power DRM transmitters are carrying regular digital transmissions, either in pure digital and/or in simulcast mode.Sometime back, AIR had issued instructions to increase the transmission hours of such transmitters in pure digital mode. Also each of the four metro cities had been asked to operate one transmitter in Pure Digital Mode. Over 80% of the Indian population was expected to be able to receive radio programs in digital. And this is before most of these transmitters started operating in pure DRM digital mode.The COVID-19 lockdown has adversely affected the digital transmission schedule in pure digital but we are confident that it will be restored soon.


The stakeholders’ efforts are also paying off, as the ecosystem for DRM digital receivers has evolved in India, from domestic chipset development to receiver design and production.The Indian auto industry has responded very positively. Over 2 million cars on Indian roads have line-fit DRM receivers, and this number is increasing every day.Five leading automotive manufacturers — Maruti/Suzuki, Hyundai, Mahindra, MG Motors and Toyota — are rolling out cars with built-in DRM receivers. Most of the other leading car manufacturers are understood to be in the process of incorporating them but are waiting to see the demand first.Development and production of standalone DRM receivers is also being taken up fast by Indian as well as foreign companies.Made-in-India Avion DRM receivers are already available online at Amazon. The DRM receiver prototype by Inntot, another India company, has been successfully demonstrated. The company paired with Clarion for manufacturing DRM car receivers and is looking for partners for starting large-scale production of standalone DRM receivers.Foreign companies — Gospell, Starwaves, Titus and Nedis — have come out with a number of models of standalone as well as car models of DRM receivers. Cambridge Consultants in the U.K. have just unveiled the prototype of a low-cost DRM receiver. Korean companies RF2Digital and AlgorKorea are also developing software-defined DRM radios.To further boost the presence of digital radio in the country, AIR has taken a number of initiatives and it held a DRM Stakeholders Meeting in February, which was addressed by the CEO and Member (Finance) of the Prasar Bharati. A Project Management Unit (PMU) has also been constituted to ensure that DRM Digital Radio is rolled out successfully.


AIR is broadcasting in the FM band also for local coverage. It provides about 43% coverage of the 1.3 billion population. Private broadcasters in India are allowed to broadcast in FM only but it is not possible to meet their demand for additional FM services, particularly in big cities, due to limited spectrum available for FM broadcasting. Their coverage is also limited to about 40%.Therefore, the Telecom Regulatory Authority of India (TRAI), the broadcasting sector regulator, has recommended that private FM broadcasters be allowed to broadcast in digital in the white spaces in the VHF band II (FM band). Though TRAI has not specified which digital broadcast standard is to be used, it is recommended that white spaces may be auctioned by 200 kHz bandwidth blocks.India is currently carrying out trials of ITU-approved standards, including DRM, in the FM band. DRM is fully compatible with the existing FM band transmissions. It utilizes the unused white spaces in the spectrum, technically unavailable for further analog FM expansion.Using DRM, in the allocated 200 kHz bandwidth, a broadcaster can transmit up to six high-quality audio services along with a host of value-added services and Emergency Warning Functionality (EWF). All digital services work without disturbing the existing analog FM services.DRM standard can be supported natively on all mobile phones based on the already available tuners for analog FM reception. No additional hardware and, therefore, no additional design or component cost is required to enable DRM digital FM support on these phones.The DRM App for mobile phones has already been developed and demonstrated by a number of organizations. Only the mobile phone manufacturers need to provide access of the baseband digital output. The mobile phone industry is also expecting the clear policy announcement for the country to start incorporating this functionality in future phone models.For legacy phone models, external FM front-end dongles have been developed. These dongles along with the already developed DRM radio app can be used to receive full DRM FM functions. This has been demonstrated successfully by a number of developers.As the DRM standard works in all the broadcast bands, most of the DRM desktop receivers available today or in development are already prepared for DRM in the FM band. Several of them have demonstrated their working in all the broadcast bands, including FM band.The designers/manufacturers of DRM receivers are thus eagerly waiting for the official policy announcements of the Indian government to finalize the digital FM support in their DRM receiver models. Use of DRM in FM band by AIR and private broadcasters in India would motivate them further to incorporate DRM FM facility in the receivers being produced and/or designed by them.It is thus the right time for India to go for digital broadcasting in the FM band, too, using the DRM standard already adopted in MW and SW bands. Indian industry is looking towards meeting the huge domestic demand and is ready for massive exports.Read other recent stories and commentaries about digital radio

Session on DRM – Advanced Radio for All



The Digital Radio Mondiale (DRM) Consortium invites you to the two hour session called 

“DRM – Advanced Radio for All” 

9th September 2020 

1000 – 1200 UTC 

At this DRM event some of its members and affiliates will showcase their latest DRM developments, products and technical advances. This is an excellent opportunity to get the latest DRM updates or simply ask questions and connect with the worldwide DRM family. 

For details click the link below: 

Friday 21 August 2020

Operation of MW DRM Transmitter in Simulcast & Pure DRM mode at single frequency(Fc-9) for reception of Digital signal

In India,so far AIR stations have been operating MW DRM transmitters in simulcast and pure DRM mode at Fc+9 and Fc digital carrier respectively. Due to different carrier frequencies for receiving digital signal, the listeners were required to tune the receivers back and forth.
The matter has been examined to overcome the inconvenience of listeners. It has now been decided to operate the Transmitter at Fc-9 single digital carrier frequency in both simulcast and pure DRM mode with effective from 01-09-2020. Inthe chart given below AIR Pune is listed at Sr. No. 23 among all other stations in India. So be tuned to AIR Pune at 783 KHZ digital carrier frequency from 1st September, 2020 and enjoy.

Wednesday 19 August 2020

DREAM DRM SOFWARE for DRM


 


DREAM DRM SOFWARE for drm receivers

Dream is a fully Open Source DRM30 and AM Software Radio with advanced features for both amateur and professional use. It runs on Mac, Windows and Linux and can be used with any receiver supported by the Hamlib radio control libraries. It supports decoding of audio, text messages, EPG, AFS, BWS, Journaline and MOT Slide Show. It fully supports the RSCI for professional remote logging. Binaries and source code are available.

The PC-based DRM+ Test Receiver allows you to investigate and demonstrate the audio and multimedia capabilities of DRM+ broadcasting as well as perform field trials and intensive measurement campaigns


For details click lin below:https:

Wednesday 5 August 2020

DRM FOR FM – MEASURES UP TO EXPECTATIONS IN INDONESIA

DRM FOR FM – MEASURES UP TO EXPECTATIONS IN INDONESIA


Radio Republik Indonesia (RRI) has just conducted measurements proving the DRM in FM is spectrum, energy efficient delivering audio and text in superior quality without any interference even in very crowded FM environments. 

RRI has always been on the forefront in the field of radio broadcasting and on-line radio.

The successful testing and measurements carried out in July came on the back of pioneering DRM deployments in the FM band.

PREPARATION 

On 10 June 2020, a digital radio transmitter was installed and commissioned by RRI at Pelubharan Ratu in Sukabumi province, West Java. For this purpose, the Digital Radio Mondiale (DRM)[1] digital radio system was used: this innovative step meant this is the first ever digital radio broadcasting station in Indonesia and in Southeast Asia.

Currently, the Pelubharan Ratu digital radio station is broadcasting three programmes in digital form, RRI Pro 1, RRI Pro 3 and, through its digital technology, news and current affairs information in textual form (in writing) in Bhasa Indonesia. The data provision is done through a digital system known as Journaline. The possibilities are immense as the system can cater to news and other information spanning 64,000 pages.

The second such digital radio transmitter was installed and commissioned on 11 June 2020 at Pantai Labuan in Banten Regency, West Java. Following this, the third DRM FM digital radio transmitter was installed and commissioned in July 2020 in Cilacap, Java Tengah province. These stations also provide similar programmes and digital services. In addition, by August 10, RRI plans to install and commission two more DRM FM transmitters in Painan, West Sumatra and in Labuan Bajo, Nusa Tengarah Timor province in eastern Indonesia.

In July RRI conducted the evaluation of trials and measurements of the Digital Radio Mondiale (DRM) technology in Pelabuhan Ratu area, Sukabumi, West Java, an area often struck by natural disasters.

These activities carried out on Wednesday (23/7/2020) and (Thursday (24/7/2020) were conducted in preparation for the implementation of digital radio.

DRM is an open all-band standard digital audio broadcasting radio technology recommended by ITU and ETSI (EN 302 245 and ES 201 980). DRM has several features and benefits including the incorporated feature of Emergency Warning Functionality (EWF).

DRM can be a digitisation solution both in the MF radio frequency band, or VHF Band II (FM). Irrespective of band, since the DRM standard is one, each DRM radio frequency channel can accommodate up to three broadcast programs (audio) along with text data (presented as news media, advertising, public information, and so on).

DRM is both spectrum and energy efficient and delivers local, regional, national and international coverage. Unlike analogue DRM can be used to achieve broader coverage using the Single Frequency Network (SFN) feature.

DRM can be used on the MF radio frequency bands using the same bandwidth as analogue (AM) and this was successfully demonstrated in Indonesia during the Bogor and Bali trials.

If DRM is used in the VHF Band II it only utilises a 96 kHz that can accommodate up to three audio channels and one data channel. This was also demonstrated by RRI in their trial conducted with the DRM Consortium in Batam. So, half the spectrum for up to three audio channels and one data channel, rather than one analogue audio only programme in FM.

In Indonesia FM is widely used in large cities, so there are not many FM radio frequencies available now. To avoid interference between FM radio broadcasts, the FM broadcast radio frequency channel is ideally separated by 400 kHz (adjacent-4). As DRM can fit in these guard spaces DRM can be a solution even in the cities with a very congested FM spectrum.

The DRM for FM RRI measurements in West Java were carried out for two days, namely 23 and 24 July 2020. The first day, they started with six Test Points (TP), namely TP1 on Karang Hawu Beach, TP2 Karang Papak Beach, TP3 Kadaka Beach, TP4 Vihara Nam Hay Kwan Se Im Pu Sa, TP5 Batu Bintang Beach and TP6 Pantai Loji.

The sixth test point location was obtained based on the results of simulated computer predictions of radiation coverage of an analogue 1 kW FM transmitter.

Measurements were aimed at technically evaluating DRM transmissions and features that can be broadcast through DRM transmitters.

CONCLUSIONS

Based on the results of the field measurements obtained in the six test points covered by the 1kW transmitter it was noted that these can be served with only 50 watts of DRM power delivering throughout a good DRM audio quality. In testing a simulcast broadcast using 1 kW and 800 Watt with spacing distance 150 kHz between the middle frequency FM and DRM, the measurement showed no interference between FM and DRM. The DRM quality was at least equally good to FM, but the sound quality of DRM was even better than FM.

The field test results are thus consistent with the ITU-R Recommendations BS. 1114 and BS. 1660. The next measurement is scheduled to be held at RRI Central Jakarta in August 2020.

Source:https://www.drm.org/drm-for-fm-measures-up-to-expectations-in-indonesia/