Picochip is the market leader in femtocells, which redirect mobile-phone signals through landlines, boosting coverage in remote areas and prolonging battery life.

ECONOMIST: Tech clusters

Mr May has also worked as a technical adviser for other start-ups, including Picochip, which is based in nearby Bath, a city famous for its Roman spa.

ECONOMIST: Tech clusters

Before he joined Picochip, in 2002 Mr Toon was one of four co-founders of Icera, which makes chips for mobile devices and employs more than 300 people, mostly in Bristol.

ECONOMIST: Tech clusters