Forget Cables and Wireless Connections and LANs and WANs, here's HANs

A Japanese telecommunications company - Nippon Telegraph and Telephone (NTT) - has developed a technology that doesn't use cables or even radio waves to communicate, instead it uses the human body as a high-speed network connection. According to NTT, it is hoping to commercialise the technology in Human Area Networks (HANs), that provide a communications link between people and electronic devices, next year.

Just how exactly does this happen?

Researchers at NTT's Laboratories in Japan have developed transceivers - that is, a transmitter and receiver - that can send and receive information by utilising the weak electric fields on the surface of the body. These fields become data transmission paths capable of speeds up to 10Mbps (bits per second) between transmitter / receivers which are kept close to the surface of the body.

The company believes the technology can be developed as an alternative to what is known as Bluetooth or WLAN (wireless LAN) technologies for very short range, high-speed communications.

Why would we want such a thing - and anyway what is a blue tooth?

There are lots of different ways that electronic devices can connect to one another. For example: Many desktop computer systems have a CPU unit connected to a mouse, a keyboard, a printer and so on. A TV will normally connect to a VCR and a cable box, with a remote control for all three components. A cordless phone connects to its base unit with radio waves, and it may have a handset that connects to the phone with a wire. In a stereo system, a CD player and other audio devices connect to the receiver, which connects to the speakers.

Companies that manufacture computers, entertainment systems and other electronic devices have realised that the incredible array of cables and connectors involved in their products make it difficult for even expert technicians to correctly set up a complete system on the first try.

Bluetooth is a standard developed by a group of electronics manufacturers that allows any sort of electronic equipment - from computers and mobile phones to keyboards and headphones - to make its own connections, without wires, cables or any direct action from a user.

From the user's point of view, there are three important features to Bluetooth:

• It's wireless. You don't have to worry about keeping track of a truck full of cables to attach all of your components, and you can design your home or office without wondering where all the wires will go.
• It's inexpensive.
• You don't have to think about it. Bluetooth doesn't require you to do anything special to make it work. The devices find one another and strike up a conversation without any user input at all.

Ok, so what types of things are immediately envisaged for these Human Area Systems right away?

Applications for HANs include security and identification functions, the company said. So imagine just by shaking hands with someone you automatically transmit your business card or by touching your laptop you automatically logon to the Internet and update your email account. Pretty much limited by your own imagination really.

Ok so we know what happens - but for those who "just have to know" how is this actually possible?

The transceivers that are used, called RedTacton, work by using an optical sensor to interpret the fluctuations in an 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; the sensor then interprets these changes as data or information flow.

Weak electric fields exist around a great many kinds of objects; these include metals, many plastics, glass, ceramics and liquids. According to NTT, they make communication between transceivers possible. 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.

So is this system safe - will people be subject to any health issues?

According to the company system is totally safe. The transmitters and receivers, which require a small electronic card to connect with an electronic device, only use 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.

Where will we first see these devices being used?

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

The company 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."

How soon will these systems be available?

The system has just been demonstrated at the company's Yokosuka R&D Center outside Tokyo on Feb. 24 and Feb. 25.

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, though they have declined to name the companies to be involved with the trials.

If the development goes well enough, and we've come a long way, we hope to have commercial HAN systems working sometime during 2006.

Arthur Hissey
Computer Research & Technology
www.crt.net.au