Once again I have the privilege of interviewing more DRM luminaries. Through the urging of my pal Benn, I contacted Dr. Pablo Angueira of the Department of Electronics & Telecommunication, University of the Basque Country, Spain. He in turn agreed to be interviewed tag-team style with his colleague and recent PhD graduate, Dr. Iván Peña. I posed several questions and below are their responses. I have to say, this may be the first time that these two illustrious gentlemen have been interviewed in English! So here we are with yet another drmna.info exclusive! Be aware that several articles about their extensive DRM research are cited in our Bibliography section.1. Firstly, DRM has been proven to be an excellent replacement for the 100 year old non-digital broadcasting technologies. Why do you think it is taking so long for it to be adopted?
The delay on the DRM adoption is not probably due to a single factor but to a combination of several circumstances. The most relevant ones are the lack of inexpensive commercial receivers, the nonexistence of a specific date for the switch off of the analogue radio broadcasting services and the fact that DRM is currently accepted by the ITU only for frequencies below 30 MHz and these bands are less attractive to radio listeners than the FM bands. Probably, the adoption process of this technology will be faster with the DRM+ standardization.
2. Both of you have studied 26 MHz local broadcasting options for DRM. Do you believe this band is viable for DRM and is it being implemented beyond experimentation right now?
It is an optimal solution to exploit more efficiently a band currently allocated for long-distance transmissions by means of sky wave propagation, but scarcely used so far due to the signal fluctuations associated to the ionospheric conditions. However, adopting a local regulatory scenario and following similar planning procedures to the ones defined for other broadcasting services in the VHF band, instead of considering international coordination, digital local services in the 26 MHz could favor the development of community radios or be used for occasional events such as festival, fairs, conferences…
Nevertheless, it is also true that broadcasters should assume mutual ionospheric interferences due to signal refractions in the Es or F layers. Regarding the implementation, it is still necessary to carry out experimental tests so as to determine the influence of regular ionospheric propagation (higher solar activity levels than the current ones will be required to obtain representative data) and also to characterize the indoor reception.
3. India has determined to use DRM as their digital solution. Do you feel it will be successful (particularly for the current lack of affordable receivers)? How about Russia and Brazil? Can DRM succeed in these countries, or is Internet service (radio listening via Internet) too strong?
We think that the DRM is a very good option considering that one of the major benefits is that it is a non-proprietary system. However, it is true that TV, radio, telephony and other multimedia services seem to converge towards Internet. Even so, Radio broadcasting and Radio listening via Internet are not mutually exclusive and specifically, the case of broadcasting in the 26 MHz band could be a good alternative for less developed countries, cities and/or areas that are characterized by a noteworthy lack of technology. After all, the installation of a DRM 26 MHz transmitter is relatively easy.
4. What do you feel are the biggest barriers for DRM implementation worldwide? What is it that holds up the manufacture of reasonably priced receivers when we now see a proliferation of nearly disposable electronic devices (MP3 players, digital cameras, etc)?
Unquestionably, the biggest barriers are the lack of affordable receivers and the need to provide a standard for both the AM and FM bands. Regarding this second aspect, it seems that will be solved in a reasonable period of time, since the DRM Consortium is making a great effort with DRM+. The problem with receivers is more complicated as the higher the number of listeners the lower the price but to increase the first ones is necessary to offer an economic solution.
The answer could be a combination of two factors: On one hand, it would be necessary to fix a date for the analogue radio switch off, since this will motivate the purchase of digital receivers by the radio listeners. On the other hand, manufacturers should do a substantial initial investment that could be relatively risky but that will make possible to come out into the market with a reasonable price. Also, it should be taken into account that the main niche market would be the car receivers, since the most common situation is listening the radio when driving and the receivers in that case are extra equipment that could be included in the car price.
Muchas gracias to Drs. Angueira and Peña for their time in answering my questions. The DRM community is very fortunate to have their expertise!
