[Updated July 27th] If you've watched Star Trek, you're familiar with some of the
technological features, particularly crew member location. Someone asks
the computer for the location of a certain crew member, and the
computer queries their badge, then responds. Well thanks to ZigBee,
that ability is now close to reality. At least the location-tracking
ability, if not the the voice-operated ability.
ZigBee is a wireless protocol built upon IEEE 802.15.4 and is related to several other wireless protocols. It's particularly useful for setting up WPANs (Wireless Personal Area Networks) of SEDs
(Service Enabled Devices). Essentially, Zigbee allows enabled
"appliances" to talk to each other, regardless of manufacturer. This
has many uses in RFID applications.
The ZigBee protocol provides
a low-speed, low-power communication for devices that need to
communicate wirelessly within a 10-meter (33-foot) range (i.e., a
WPAN). WPAN clusters can be connected together to extend that range.
There
are three frequencies that provide different bit transfer rates. The
most commonly used frequency is 2.4 Ghz, which provides 250 kbps
(kilobits per second). Other shorter-wave frequencies offer lower
transfer rates. This protocol allows communication with Wi-Fi,
Bluetooth, and other wireless networks as well.
ZigBee is not an
alternative for RFID, but is rather a network platform, enabling RFID
devices to communicate with each other as well as other networked
devices.
This ability of ZigBee is being demonstrated at Saint
Luke's East-Lee's Summit Hospital in Lee's Summit, Missouri, part of
the Kansas City metropolitan area. The trials there allow hospital
staff to locate patients wearing RFID-enabled badges.
RFID readers query for badges, and if any are present, transmit signals
over the ZigBee WPAN network. The system has allowed doctors, nurses,
and other staff to find patients, on different floors, with a high
degree of accuracy.
These results bode well. Besides closed systems such as unwired hospitals, a similar RFID + ZigBee setup could be used by miners or any environment where the safety of individuals is enhanced by non-intrusive tracking methods.
Additional sources: [Expert Answer Center, IEEE WPAN projects, Network World]
Note: As per RFBase's comment below, this is a correction. The ZigBee capabilities demonstrated at St Luke's Hospital consists of the RFID tags inside patient badges querying for RF transceivers and communicating via ZigBee. There are no RFID readers, per se, and thus these do not communicate over a WPAN network, as indicated above.
Apologies for the error. Thanks to RFBase for the heads up.