Maspro Denkoh, a Japanese manufacturer of wireless communications equipment, has developed a transmission system that can send WiFi signals as far as five kilometres.

The system relies on high gain antennas produced by the company and is compatible with standard IEEE802.11b/g communications equipment.

There are two types of antenna: one is a tube-shaped model about 40 centimetres long and the other is a much shorter and square-shaped model. Combining two of the tubular antenna - one on each end of the link - will result in a transmission distance of about five kilometres while one of each antenna will work on distances up to two kilometres and two of the compact antenna will be fine for up to a kilometre, the company said.

They can be used with standard wireless LAN equipment that support external antennas.

Maspro is promoting the system as part of a security and monitoring solution, shipping a bundle containing a camera, software and antenna. Systems cost around £2,800. The company has no plans to sell the solution outside Japan.