Page 16 - EngineerIT June 2022

RADIO COMMUNICATION

HF radio receives new life in

Indo-Pacific

By Hans van de Groenendaal

What’s old is new again across the vast contested region

he US military is returning to users of the spectrum and have in recent years developed various new digital modes.
an old friend to help conquer WSJT is a form of digital communication mode optimised for weak signal amateur radio
Tthe tyranny of distance in an communication and extensively experimented with. WSJT was originally developed by
increasingly contested area. The Defence K1JT around 2000 / 2001 but now the software is open source, and its development is
Information Systems Agency is working continuing under the management of a small team of radio amateurs.
with its forces in the Indo-Pacific region In an area of operations covering half the Earth’s surface, the Indo-Pacific region in
and around the world to bring back high- recent years has relied extensively on satellite and undersea fibre links to connect diverse
frequency (HF) radio communications as locations. But space assets are increasingly vulnerable both to space conditions and
a key link for operations in potentially enemy action in orbit and on the Earth, and fibre cables on the sea bed can be damaged
difficult or denied environments. accidentally by anchors or deliberately by adversaries operating undersea systems in
HF radio has for some time been put shallow waters. High frequency radio can provide over-the-horizon communications
on the back burner as many countries connectivity without the need for a fragile infrastructure, and the increasing threats to
have stopped their international other systems in the Indo-Pacific region have brought it back to prominence.
broadcasting on HF frequencies and Robert K. Ackerman, former editor in chief of Signals magazine, recently wrote that
moved to satellites. The invasion of one Defence Information Systems Agency (DISA) official described the resurgence of HF as
Ukraine by Russia has made some becoming big and moving fast. Coupled with the next generation of HF capabilities, such
broadcasters dust off their shortwave as wideband HF and various waveforms, HF now is looming as a redundant capability.
transmitters to beam programmes to the HF is not a panacea for replacing satellite or fibre, DISA officials say. It does not
conflict areas. In Africa, HF radio is used have the data rate the other two media provide, so users will not have the same level
by some broadcasters and the military. of throughput they can obtain from a satellite or fibre optic cable. “US forces will need
Radio amateurs world-wide are extensive to be certain that personnel are trained to be able to communicate using short bursts

Picture by Collins Military Radio (9pt)

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