The trials are a collaborative project with BT partnering Lumenisity, a Southampton University spin out company, and open radio access network (O-RAN) mobile vendor, Mavenir.
The tests are being carried out at BT’s research and engineering campus, using a 10km-long hollow core fibre cable provided by Lumenisity. It will be used to test a variety of use cases, including potential benefits for 5G networks and ultra-secure communications, like Quantum Key Distribution.
“We’re excited to begin trialling hollow core fibre and to discover the potential opportunities and benefits of deploying this technology in certain scenarios,” said Professor Andrew Lord, head of optical network research at BT.
“This new type of fibre cable could play an important role in the future of the world’s communications infrastructure, heralding a step-change in capability and speed, to keep up with the demands for high-speed, low latency communications driven by 5G networks, streaming, and more.”
At present, global networks use single-mode optical fibre, which is made up of solid strands of glass that quickly carries information over long distances by channelling light from laser transmitters through the glass strands.
However, glass naturally means that this light travels marginally slower inside the fibre than it would in air. So instead, this new fibre has an air-filled central core, with an outer ring of glass, to guide the laser beam whilst maintaining the signal speed at very close to the ultimate speed of light.
Trials such as these into hollow core fibre explore how to enhance the capabilities of optical fibre, with the potential to reduce the latency, or signal delay by up to 50%.
“Lumenisity is delighted to be the supplier of field deployable CoreSmart® hollowcore cable for these trials with BT. This is further evidence of the impact our unique low loss, high performing cables can have on the networks operated by our carrier partners,” said Mike Fake, director of product management at Lumenisity.
Together with Mavenir, BT has demonstrated that using hollow core fibre can increase the distance between street antennas and the back-end processing in exchanges.
Thanks to the low latencies this creates, use of hollow core in the radio access network could reduce mobile network costs by allowing more 5G antennas to be served from one exchange or cabinet. Other potential benefits include high frequency trading.
“The ability to extend the reach of fibre connected radios only further demonstrates the power of Open RAN and its Eco System. This improvement will significantly increase the number of use cases that can be served from containerised cloud based Open RAN solution,” said John Baker, senior vice president of business development at Mavenir.
