-
- A new way to transmit pictures has been
developed that could hugely cut the cost of sending information around
the world.
-
- The same technology used to transmit
shortwave radio signals could be used to send images without the need for
expensive cables or satellites.
-
- High-frequency radio waves can be picked
up virtually anywhere in the world with a relatively cheap radio set, as
everyone who listens to the BBC World Service on shortwave knows.
-
- But radio waves that can carry sound
and voice can also carry data. This has been exploited by engineers working
for the British Defense Evaluation and Research Agency and for Lancaster
University in the UK, who have developed a system that connects a digital
camera to a radio transmitter.
-
- Static problems
-
- Pictures taken with the camera are translated
into electrical signals and then transmitted via radio without the need
for expensive landlines or satellites. But there is one problem - static.
-
- The interference that often makes it
impossible to listen to radio transmissions. The scientists faced the same
problem when they tried to transmit their pictures, but they say they can
separate the signal from the background noise.
-
- "We've come up with a special unique
coding technique that actually gives enough protection to the data, so
that when it's passed over this quite distortive medium, we can still get
images out at the other end," said scientist Paul Arthur.
-
- They have successfully tested this system
by sending pictures over a distance of 80 kilometres and the nature of
shortwave radio means it is actually simpler to transmit signals over much
longer distances.
-
- This system could be used to transmit
x-ray photographs between hospitals, send electronic books to schools or
simply as a fax machine without a telephone network.
-
- For many people living in remote areas,
pictures on the radio could open a whole new window to the world.
|
