Zinwave, whose indoor wireless system distributes multiple radio signals over multimode fibre, has updated its product to use standard antennas, and opened a US office to meet international demand for in-building wireless technology.

"We've made the transition from a technology let project to a proper commercial concern," said Mike Baker, chief executive of the company which a year ago announced patent-pending technology that breaks previous range limitations, distributing wideband signals that can include cellular, 3G, Wi-Fi and other radio technologies through cheap multimode fibre in buildings.

The system can now use standard office-friendly omnidirectional antennas, with separate antennas for each wireless service that can be placed unobtrusively on ceilings. Until now, Zinwave needed large flat directional antennas that had to be placed on the inside of external walls, beaming the wireless service within the building.

"It gives the customer the ability to use a coax converter, separate the antenna from the electronics, and get increased range," said Baker. Different antennas are available for US and European cellular technology, for Wi-Fi and for public radio communication services such as Tetra.

Zinwave's technology is still something of a mystery, at least till patents are issued, but it is understood to be based on the Friday project (fibre radio for in-building distributed antenna systems) led by University College London, with Cambridge University, Agilent and Remec, which showed the ability to carry 802.11b signals 1km over "worst case" fibres in 2003.

"IT managers hate single mode fibre, because a single speck of dust on it is catastrophic," said Baker. Multimode fibre is still almost universal in buildings that have fibre, and Cisco mandates it for 10 Gigabit Ethernet, he added.

ABI Research recently tripled its estimate of the size of the market, predicting a $3.6 billion market in 2011 for in-building radio systems in large enterprises. Fashionable picocell and femto cell systems make up only a small part of this, said Baker, as they are suitable for smaller buildings.

In response to the potential market, Zinwave has opened a US office in Boston. "The market size is roughly equal in the US and Europe," said Baker. The US has a lot of mature installed fibre, and given the size of the country, there is still often poor cellular coverage, particularly in new developments