文档介绍：外文原文
ZigBee: Wireless Technology for Low-Power works
Gary Legg
5/6/2004 12:00 AM EDT
Technologists have never had ing up with potential applications for wireless sensors. In a home security system, for example, wireless sensors would be much easier to install than sensors that need wiring. The same is true in industrial environments, where wiring typically accounts for 80% of the cost of sensor installations. And then there are applications for sensors where wiring isn't practical or even possible.
The problem, though, is that most wireless sensors use too much power, which means that their batteries either have to be very large or get changed far too often. Add to that some skepticism about the reliability of sensor data that's sent through the air, and wireless sensors simply haven't looked very appealing.
A low-power wireless technology called ZigBee is rewriting the wireless sensor equation, however. A work technology that rides on top of the recently ratified IEEE radio standard (Figure 1), ZigBee promises to put wireless sensors in everything from factory automation systems to home security systems to consumer electronics. In conjunction with , ZigBee offers battery life of up to several years mon small batteries. ZigBee devices are also expected to be cheap, eventually selling for less than $3 per node by some estimates. With prices that low, they should be a natural fit even in household products like wireless light switches, wireless thermostats, and smoke detectors.
Figure 1:  ZigBee work, security, and application-services layers to the PHY and MAC layers of the IEEE radio
Although no formal specification for ZigBee yet exists (approval by the ZigBee Alliance, a trade group, e late this year), the outlook for ZigBee appears bright. Technology research firm In-Stat/MDR, in what it calls a "cautious aggressive" forecast, predicts that sales of nodes and chipsets will increase from essentially zero today to 165 mi