The Road Wirer
teeth in your car?
by Mark Sedenquist
In January, 2000, I wrote about Bluetooth, a new radio technology that holds the promise of being the means to eliminate some of the myriad cables and wires that are currently stowed inside most dashboarders' vehicles. Recent published reports offer some tantalizing visions using this wireless service.
As a dashboarder, I guess it would be interesting if, when I entered the cockpit of the Phoenix One, the accounting database on my laptop was automatically updated with the current mileage and gas consumption figures derived from the onboard computer. And it might be nice if my cell phone and Palm Pilot could exchange telephone numbers and update my electronic address book. And what a convenience it would be if the GPS-enabled on-screen "glass cockpit" navigation monitor could automatically display the closest grocery store information. The recent mission of the Atlantis space shuttle featured the use of a series of 10 high-resolution flat-screen monitors that replaced the traditional analog gauges with what is being called a "glass cockpit," and I find the term intriguing. Could a "glass cockpit" powered by Bluetooth allow me to transfer images and files between the Internet and my PC without having to connect the usual snarl of cables linking the modems, PCs, and cameras? Now, some thirteen months later, it doesn't really look like we're any closer to the wireless nirvana Bluetooth keeps promising.
To my knowledge, no one has yet built-and road-tested under real conditions- a Bluetooth-enabled device intended for primary use in a vehicle. In recent weeks, I have seen demonstrations of wireless local area network systems (W-LAN) that were sitting in vehicles- but these vehicles were parked in trade show exhibits, not actually being used on the road. So, what is the deal?
Bluetooth was originally envisioned by its creators at Ericcson as a way to connect a variety of handheld communication devices like PCs, cellular phones, Palm Pilots, electronic organizers, etc., without using cables. The name, the story goes, was the moniker of a Danish Viking, Harald Blåtand , who ruled most of Denmark and Norway in late 900 A.D. Harald consumed vast quantities of blueberries, which stained his teeth and earned him his nickname. Because he was also famous for forging a kingdom from a wildly disparate collection of people and cultures, the developers of Bluetooth decided to name their electronic radio system after him.
These three competing technologies use microchips that house very tiny radio transceivers which operate on the ISM, (Industrial Scientific Medicine) frequency band. This ISM band is considered unlicensed radio by the FCC and operates in the 2400 to 2490 MHz range, also known as 2.4GHz. Depending upon how much power these little radio transceivers use, information (voice, music or video) can be sent wirelessly between devices in a range from 30 feet to nearly 300 feet. Data transfer speed in a two-way mode can be around .430Mbps (Bluetooth) to something approaching 5Mbps (in 802.11(b) and HomeRF). It is common to see these relative speeds expressed as 1Mbps for Bluetooth and 11Mbps for HomeRF, but these optimal speeds are only in one direction - not a very useful calibration if one is using them for content transfer.
The romance of blueberries notwithstanding, I find little reason for optimism that Bluetooth will be of much use for dashboarders until such time as true broadband wireless service becomes available for mobile platforms. There is little point in using Bluetooth-enabled devices, (with their inherent speeds of 434K) to log on to the Web when the source (digital cellular) service rarely exceeds 12-14K. In addition, there is significant potential radio frequency interference in the vehicle environment that could prevent or dissipate the effectiveness of the Bluetooth or any other 2.4GHz radio transmission.
I have asked Sam Churchill, a wireless gadget enthusiast from Portland, Oregon and a contributor to the RTA Wireless Forum to research the current state of affairs of Bluetooth and share his findings with us. Next week, his interview with Nigel Ballard from Cerulic, Inc., a supplier of embedded systems to enterprise-level companies using Bluetooth and 802.11(b) wireless LANs.
Las Vegas, Nevada
February 19, 2001