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Engineers at Glasgow University have won Pounds 1.5 million from the Engineering and Physical Sciences Research Council to develop the technology for a new generation of optic fibre communications.

Their goal is to build integrated circuits the size of a drawing pin which will enable telephone, television and other signals to be relayed as light pulses travelling along optic fibre cables at an increased rate of 20 billion bits per second. This ten-fold increase would allow 300,000 telephone calls, 200 TV signals or ten high-definition TV signals to be carried simultaneously. One starting point for the optoelectronics research group is the semiconductor diode laser, already mass produced for use in CD players and similar equipment. Switched rapidly off and on, it can send information at the rate of two billion light pulses per second. The information rate could be dramatically increased by combining the laser with a separate modulator device to shape each pulse of light.

The Glasgow team is also looking at the potential role of optoelectronic devices in converting light signals into radio waves. A signal could be carried long distance by optic fibre cables buried underground. Converters mounted at intervals, on lamp posts for instance, would transform the optical signal into high frequency radio signals which could be received at high quality over short distances.