NTT has developed technology that uses the human body as a high-speed network and forms a communications link between people and electronic devices.

Next year, the company hopes to starts selling products to build what it calls Human Area Networks or HANs.

Researchers at NTT's Microsystems Integration Laboratories in Atsugi, west of Tokyo, have developed transceivers that can send and receive data by using weak electric fields on the surface of the body. These fields become data transmission paths capable of speeds up to 10Mbit/s between transceivers kept close to the surface of the body, according to the company.

The company believes the technology can be developed as an alternative to Bluetooth or WLAN technologies for very short range, high-speed communications. "If the development goes well enough, and we've come a long way, we hope to have commercial HAN systems working sometime during 2006," said Toshiaki Asahi, a researcher at the company's strategic business creation team. Applications for HANs include security and identification functions, the company said.

The transceivers - called RedTacton - work by using an optical sensor to interpret fluctuations in the electric field of the human body through the use of a miniature laser and a crystal mounted in the transceivers. The laser measures the fluctuations in the field and how these fluctuations affect the crystal, and the sensor interprets these changes as data.

The weak electric fields that exist around many kinds of objects - including metals, many plastics, glass, ceramics and liquids - make communication between transceivers possible, NTT said. The system is able to work through socks, shoes and gloves, and on both dry and oily skin. A person equipped with a sensor can exchange data with another person carrying a sensor by shaking hands, and between a person and a device by touching it, walking on it, or by sitting on it, the company said.

Unlike communications technologies such as Bluetooth, NTT's system does not suffer from interference issues, and people equipped with transceivers can communicate with each other via shaking hands even if they are wearing rubber gloves, NTT said. Secure communications will be possible by combining the system with encryption, it said. The system is also safe, the company said.

The transceivers, which require a PCMCIA card to connect with an electronic device, use several hundred milliwatts of power and are insulated to avoid electric shocks. As with many items of household electrical equipment, like TVs and kettles, the transceivers do emit very weak electromagnetic fields, but the levels are in compliance with guidelines issued by Japan's Ministry of Internal Affairs and Communications, NTT said.

The company is considering shrinking the interface for the transceivers so that they are small enough to be embedded in mobile phones and other devices that have slots for CF (CompactFlash), SD, and MemoryStick cards, Asahi said.

"We are thinking that we can use the system with the current types of transceivers, but we are also thinking of how to make them smaller. To do this, we have to shrink the (chips used in the system) but as we have developed all the key technologies, this is not something that will take years," he said.

NTT will start field trials of the system from April through September. The company will work with large electronics companies and architects and building companies, Asahi said. He declined to name the companies to be involved with the trials.