ARLA/CLUSTER: NATO-ISAF: Tecnologia NVIS ao serviço da população no Afeganistão.

[João Costa > CT1FBF]

NVIS Short Wave technology in Afghanistan

ISAF report that a Virginia National Guardsman has found a new use for
Near Vertical Incidence Skywave (NVIS) short wave radio in
Afghanistan.

The song “video killed the radio star” was the first video played on
MTV in 1981 and launched a music revolution. Soldiers of the Virginia
Army National Guard’s 116th Infantry Brigade Combat Team are deploying
technology in a revolutionary way in Afghanistan using a short wave
radio transmitter that can reach almost every radio in Zabul province.

This is the first time a province-wide transmitter has been used in
Afghanistan. The transmitter allows the Zabul provincial and district
government to send messages to rural Afghan homes.

“No other unit in the International Security Assistance Force has ever
done this at any level,” said Master Sgt. Joel E. Fix of Fort Belvoir,
Va. speaking of the novel application of the technology. “We have the
ability to target the signal toward specific districts or the whole
province.”

Radio and word of mouth are the primary means of spreading news and
information in rural Afghanistan. Listening to the radio – thousands
of which were distributed by NATO-ISAF - is a cultural norm for
Afghans, many of whom follow both the BBC and Voice of America.

Fix, a 14-year veteran of the Guard on his third overseas deployment,
came up with the transmitter solution in response to a problem raised
in discussions with Afghan officials: “How could the Government of the
Islamic Republic of Afghanistan communicate to their people in remote
areas?”

It was a particularly timely dilemma. As GIRoA expanded its influence
into every district, GIRoA’s continued legitimacy rested on the
ability to reliably reach and involve ordinary Afghans in their
parliamentary democracy. Specifically, the district governors of Mizan
and Day Chopan in Zabul province each wanted to invite the elders of
their districts to grand shuras in September 2011.

Day Chopan has the highest elevations of Zabul province with deep
valleys unreceptive to radio signals.

The 116th “Stonewall Brigade”, in partnership with Romanian troops and
Soldiers of the Alaska-based 1st Battalion, 24th Infantry Regiment,
all members of Combined Team Zabul, came together to brainstorm a
solution. Traditional options raised by CTZ such as leaflet drops,
broadcasting radio transmissions from aircraft and even flying
aircraft with loudspeakers attached were all denied.

“The government was looking for ways to communicate with people on a
greater scale, but there were gaps in the coverage. Short wave radio
is the solution we came up with,” said Fix.

Short wave radio is known in the U.S. as ham radio which allows two
way communications. The Zabul transmitter is one way. Most radios used
by Afghans are receive-only.

“I was soliciting for bids for a transmitter and was referred to Don
Butler to assist with the project,” said Maj. William R. O’Neal a
Smithfield, Va. native with the 116th.

Butler, an Air Force veteran from the ‘60’s, is a ham radio enthusiast
from Gun Barrel City, Texas who provided design help for the
transmitter. Butler’s call sign is N4UJW.

“Ham radio is two way communications over short wave. Our transmitter
is one way,” said Fix. “With this configuration, no matter where they
are, there’s no reason the Afghan’s can’t get a signal. The frequency
is close to but not the same as the one for the BBC. That makes it
easy to find and remember,” he added.

The transmitter owes its success to a technique called NVIS – Near
Vertical Incidence Skywave – which involves bouncing radio signals off
the ionosphere – a layer of the atmosphere. Two NVIS antennas are
placed horizontal to the ground unlike a traditional vertical
transmitter. The second part of the NVIS antenna is called a ground
wire and helps to boost the signal by forcing it to go straight up
instead of outward and limited by the curve of the earth.

“In a traditional short wave broadcast, you get your antennas up as
high as you can go,” said Fix. “It bounces off the F2 layer of the
ionosphere but gives you limited coverage with ‘skip points’. Using
NVIS and our reflector wire, the signal goes up at a very steep angle
and straight back down which can penetrate deeper into mountain
valleys. When we were looking at this system, it was a no brainer,” he
added.

The transmitter is operated and maintained by coalition forces
including the U.S. and Romanian soldiers and broadcasts content from
the local government. At first glance it doesn’t seem very impressive:
two antennas, the ever-useful 550 cord, and some wire that feeds into
a box with one port and an on/off switch.

“Our goal is to transfer the transmitter to the provincial government
as part of the transition,” said O’Neal.

Unlike some new technologies developed and used as part of Operation
Enduring Freedom, this transmitter is inexpensive and effective.

“It has resulted in a savings of around 3,100%,” said Fix. “It would
take 30-32 FM systems to cover the same area.



Fonte: Afghanistan International Security Assistance Force (ISAF)

http://www.isaf.nato.int/article/news/video-killed-the-radio-star-virginia-national-guardsman-finds-new-use-for-old-radio-technology-in.html