All the better to hear you with

Birmingham University spin-out Cryosystems is developing superconducting filters that can be fitted to mobile phone companies’ base stations to improve their range by 25%.

Developed using a £6m investment from the EPSRC, the filters will make the base station more sensitive, allowing people to go further away from it and still receive a signal, said Professor Mike Lancaster, a director of Cryosystems and head of the University’s Emerging Device Technology Research Centre.

‘If you have a more sensitive receiver, you could also use less power in a mobile handset too, resulting in less radiation and longer battery life,’ he added. Reducing the radiated power of the phone would also ease the safety fears that have consistently dogged the devices.

The researchers are also looking to use the filters in radio astronomy, and are working with Jodrell Bank to test the devices. In August, the team will install a filter on the giant Lovell Telescope, one of the biggest telescopes in the world, to test its ability to improve the clarity and speed of viewing interstellar objects.

Cryosystems is now attempting to produce production models of the filters for commercialisation.

The filter itself, a square of around 1in by 1in, consists of the superconducting material yttrium-barium-copper oxide on a plate of sapphire crystal. It is combined with a high-frequency amplifier, and placed within a cooler, as the superconducting material must be kept at 60 Kelvin.

The system is connected at one end to the antenna, and at the other to the electronic equipment within the base station itself. The company expects the filter to cost around the same as existing systems, but with much better performance.