RADIATE (Radio DIgital Am Tests)
Start date: 01/11/2000
End date: 30/04/2002
Action line: IST 1999 - IV.5.4
Main Objectives
The rapid replacement of analogue technology with digital technology in communications, including television
and radio transmissions has not yet affected AM broadcast bands up to 30MHz. They still remain analogue,
and therefore providing low perceived quality and not optimising the use of scarce spectrum resources.
However the AM broadcast bands use frequencies which exhibit particularly beneficial propagation
characteristics; with wide area coverage, either with ground-waves in the case of the Long-wave (LW) and
Medium-wave (MW) bands, or sky-wave propagation in the case of the Short wave (SW) and MW.
A digital transmission system, which could replace the current analogue system, holds the prospect of virtually
eliminating the effects of noise and varying propagation for the listener whilst retaining and enhancing the
beneficial propagation characteristics of these frequency bands. To create that system, an international
consortium was inaugurated in 1998 under the name of Digital Radio Mondiale (DRM) that brought together a
number of broadcasters, transmission operators, transmitter, receiver and integrated circuit manufacturers,
research laboratories and broadcasting unions, with a high proportion of European members. DRM set out a
new digital transmission specification, drawing on work previously done within a European Eureka project,
NADIB, where a preliminary system was designed and tested within the laboratory, using transmitter and
channel simulations.
The RADIATE Project will verify the new standard proposed to the ITU by the DRM consortium for digital
broadcasting of audio and data in the AM bands at frequencies below 30 MHz using a system developed by
the DRM consortium and performing the field testing work that needs to be undertaken to confirm the correct
operation of the different systems modes and features, and the successful reception of broadcast over a
range of propagation conditions.
Technical Approach
An evaluation criteria document will be produced defining the usability, performance and economic criteria
against which the system will be evaluated. A test plan will then be drawn up in consultation with the DRM
technical committee. This plan will describe in detail the transmitters which will transmit to which locations
and when, the locations of the prototype reference receivers within the target area for the transmission. The
planning stage will also define the test signal for both audio and data.
Existing transmitter exciters, receivers and software will be modified or adapted to enable them to work with
the new DRM system. Existing transmitters belonging to the partners will be modified to accept the prototype
equipment while staying within the ITU regulations
The signal will be received and recorded by the prototype receivers for analysis. The analysis of the data will
seek to confirm that the system operates correctly over a broad range of frequencies, propagation conditions
and signal paths. The analysis will commence with the first transmissions providing feedback to the
transmitter operators and manufacturers such that modifications of the transmitter and receiver equipment can
take place during the trial.
The results of the analysis will provide data on the systems performance for the RADIATE partners, DRM
technical committee and the ITU. The DRM system and digital broadcasting in the AM bands below 30Mhz
will be demonstrated at broadcasting conferences and exhibitions around the world to encourage the uptake
of the technology.
A frequency planning and Network planning recommendation will be produced based on the data gathered
during the trial. It will provide data to allow the modification of the existing service planning tool
Key Issues
• To verify that digital broadcasting in the AM bands, 30Mhz is viable using the standard and system
developed by the DRM consortium.
• To confirm that the DRM system features operate as expected over a broad range of reception conditions
• To show that the expected improvement in both audio quality and reception reliability is consistently
achieved
• To demonstrate data transmission using the DRM system
• To confirm that the ITU requirements for digital systems are met
• To demonstrate that DRM broadcasts comply with broadcast legislation and can co-exist with analogue
broadcasts
• To gain experience in adapting existing transmitters for DRM use
• To collect and analyse data from the transmitters and receivers
• To gain sufficient operating experience to enable the partners, to have an advantage in the operations and
commercial exploitation of the medium when DEM services are introduced
• To produce a frequency and network planning recommendation for digital broadcasting in the AM bands
below 30Mhz.
Expected Impact
The size of the receiver market is conservatively estimated to be in excess of 2.5 billion receivers worldwide,
of which some 700 million are estimated to cover the SW bands. The change of the receiver base from
analogue to digital transmission will require many years to accomplish, even at replacement rates of 100 to
200 million receivers per year.
In the case of the transmitter base there are estimated to be over 1000 high power Long, Medium and Short
wave transmitters in the world, with several times that number of lower powered Medium wave transmitters in
use today. This provides a significant market opportunity for both the existing RADIATE partners and also
other DRM Members, which are involved in the manufacture of low to high powered transmitter design,
installation and manufacture.
List of participants
Merlin Communications International Ltd
British Broadcasting Corporation
Radio Canada International
Thales Broadcast and Multimedia SA
Thales Broadcast and Multimedia AG
T-System Nova Deutsche Telekom Innovations
Gesellschaft mbH
Fraunhoffer Institute for Integrated Circuits (IIS-A)
Radio Nederlands Weldomroep
Deutsche Welle
TeleDiffusion de France
Contact
UK
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Steve Gray
UK & Overseas Operations Manager
Merlin Communications International Ltd
Rampisham
Transmitting
Station,
Rampisham Down,
Dorchester. DT2 0HS.
Tel: +44 1935 482100
Fax: +44 1935 482133
E-mail:
Steve.Gray@merlincommunications.com
Web page: www.ist-radiate.com