Norway Tests DAB+ on the Water
Norway is famous for fjords and beautiful coastlines. The Scandinavian country
has 25,148 kilometers of coastline, making Norway owner of the eighth largest
coastline in the world.
of the boats involved in the trials with the
in the background. Photo courtesy Gunnar Garfors
Norway has a large
fishing industry, and they, like everyone else, listen to the radio. Radio
reception can be a matter of ensuring the safety of the crew: few small fishing
boats have internet access, and public broadcaster NRK produces a weather radio
station, NRK Vær, specifically made for those who work at sea.
However, early next
year, Norway becomes the first country to start switching off FM transmissions
in favor of terrestrial digital broadcasting via DAB+. Any switchoff of FM
transmissions needs to consider all radio users — even those in fishing boats
off the coast.
So, throughout the Norwegian summer, with
temperatures hitting a balmy 50 degrees F (10 degrees C), three NRK engineers
packed a variety of radio monitoring equipment, a few portable DAB+ sets and
took to the waves.
Advisor Jørn Jensen tests DAB+ signal
on the water. Photo
wanted to see the how far from shore it’s possible to receive signals, and the
quality of them: DAB reception offshore is not an official requirement for us,
but we wanted to offer it anyway,” NRK’s Head of Distribution Øyvind Vasaasen
told me via email. “We also wanted to test various receivers, and to test
antenna solutions on boats.”
As long as a transmitter
is well-situated and not shaded by buildings or mountains, a transmitted signal
should travel quite far: though the curved surface of the Earth will eventually
stop reception at 190–240 MHz, the frequencies being used for DAB. “We can’t find
evidence that fog or rain have any practical negative effects on the
reception,” Vasaasen told me, further highlighting the reliability of a good
NRK Advisors Gunnar Garfors, Jørn Jensen and
Michel Gascoin ran a set of tests from a number of different locations off the
Norwegian coast — in a variety of search and rescue boats piloted by the
Redningsselskapet sea rescue group.
Gascoin, NRK advisor for distribution,
gear on the boat. Photo courtesy Jørn Jensen
As ever with digital
reception, the quality of the antenna made all the difference — an antenna made
for cars didn’t perform that well, nor did a split FM/DAB antenna. However, a
specific marine antenna, made for DAB reception, performed excellently.
“The reception was even
better than our calculations predicted,” said Vasaasen. “Our aim is to offer
DAB reception 50 kilometers (30 miles) from the shore, and with the external,
marine antenna this was always possible within this range corresponding to the
coverage map and even much further.”
The hero, though, was a small, battery-powered
consumer DAB+ radio with a telescopic antenna. In a trip from the working port
and tourist town of Ålesund, the Sony XDR-P1DBP received signals a staggering 132 kilometers
(82 miles) from land.
One further discovery: Radio engineers don’t
always cope well with bad weather. Seasickness isn’t fun at the best of times:
but two of these trips, which lasted four and a half hours, were very stormy
Garfors, NRK advisor, tests DAB+ reception.
However, for everyone
working on what’s inevitably been dubbed “FMexit,” this was welcome validation
of the coverage plan and reception characteristics of Norwegian’s DAB+
On Jan. 11 at 11:11 a.m.,
the first of many FM transmitters will go silent in Norway, appropriately in
the coastal town of Bodø. Radio-loving Norwegians should relax, safe in the
knowledge that even if they’re out fishing, they’ll still be able to tune in.
James Cridland reports
on the industry for Radio World from Brisbane, Queensland.
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