The dawn of a new wireless experience
The unwiring of America continues apace, from our laptops to the phones on our hips -- and soon, perhaps, our thermostats. It began further back than many people realize. Just look at your TV remote control. That uses infrared radiation -- basically a kind of light that's undetectable to the eye. But infrared has some limitations. For one, there's the line-of-sight thing. Like a beam of light, infrared travels in a straight line, so your remote has to be pointing at the TV set in order to work. It'd be tough to use an infrared wireless headset with a cellphone; toss the phone in your pocket, and you'd break the connection.
Enter Bluetooth radio networking. With a range of about 30 feet and an indifference to personal attire, Bluetooth wireless headsets have begun to catch on worldwide. But Bluetooth is on the same frequency as those WiFi wireless data networks so many of us have installed. So signals from a Bluetooth phone will sometimes interfere with the Internet data flowing into a WiFi-equipped laptop. Indeed, one Bluetooth phone may even interfere with another. This sort of thing is always an issue when different radio devices share the same frequencies.
So why not get rid of the radio, for products like headsets? Not with an infrared headset -- we've considered that. There's another option -- magnetism.
Wilmington's Aura Communications was started in 1995 by scientists from the Massachusetts Institute of Technology. The company's latest product, the result of six years' labor, is a chip called LibertyLink that generates an incredibly weak magnetic field, a "bubble" about five feet in diameter. The chip can then transmit data by modulating the magnetic field at low frequencies -- 10 megahertz or so, compared to 2.4 gigahertz for WiFi and Bluetooth. But even during modulation, the magnetic field emits no radio waves, so the headset can't interfere with any other wireless devices.
Now, just plug a LibertyLink device into your cellphone, don the wireless headset, and you're ready for a nice, long chat. Especially since the whole thing can deliver up to 25 hours of talk time on a single double-A battery, according to vice president of sales Dan Cui. The Globe didn't confirm Cui's 25-hour claim; even journalists don't talk that much. But Aura's magnetic bubble technology still seems like a winner. A prototype of the system, plugged into a standard cellphone, worked exactly as advertised.
A Michigan firm, Fonegear LLC, plans to have LibertyLink headsets on store shelves in time for Christmas, at a price that demonstrates another advantage over Bluetooth. An equivalent Bluetooth headset, the Jabra FreeSpeak, runs about $130; Fonegear's headset will cost about $60.
And that's just the beginning. Cui says NASA is interested in putting LibertyLink chips into future spacesuits, so the suits can relay life-support data to receivers mounted inside the space shuttle. And the next generation of the chips will support high-fidelity music, so a cellphone can double as a wireless MP3 music player. There's even a manufacturer of airline seats who wants to embed LibertyLink chips inside the headrests, then hand out wireless headsets to the passengers. You couldn't do that with radio chips that might muck up the navigation gear in the cockpit. But a mild magnetic field never hurt anybody.
Here on the ground, there's still plenty of work for radio-based wireless, and new ideas continue to sprout. One of the latest has a name even sillier than WiFi. It's called Zigbee, and it may finally bring about the long-awaited era when we can manage our homes by remote control.
Zigbee is a lot like WiFi, only weaker and much cheaper. While WiFi devices have a range of up to 300 feet, a Zigbee will only reach about 30 feet. Each Zigbee chipset is expected to cost just a few bucks and will run on a standard battery for a couple of years. That's because you'll only use them in brief bursts.
Say you've got a Zigbee inside your refrigerator, and it begins to malfunction. The fridge's diagnostic computer notices the problem and generates a trouble ticket. This gets handed off to the Zigbee, which sends a digital data burst to your home's wireless network, and from there to Ol' Lonely at the local Maytag dealership.
We've been hearing about such automated appliances for years. Why haven't we seen them? Because the necessary devices cost too much and are too hard to set up. A consortium of 50 leading companies, including Philips, Motorola, Intel and Hewlett-Packard, think that Zigbee is finally simple and cheap enough to make a go of it.
But never mind those guys. How about Leviton Manufacturing Co., a maker of light switches? Or Honeywell International Inc., the world's leading producer of thermostats? They're members of the Zigbee consortium too. And they're the ones that really matter. When the real estate ads boast of new houses with Zigbee light switches and thermostats, you'll know that home automation is finally for real.
Hiawatha Bray can be reached at firstname.lastname@example.org.
© Copyright 2003 Globe Newspaper Company.