Here comes ZigBee

Zigbee^TM is a short range wireless personal area network that can be used for onsite tracking, its strength is that it can be incorporated into small chips that consume little power and are relatively inexpensive. These chips can then be integrated into low-cost, low -power devices that can “sleep” for 99% of the time until awakened by a beacon signal.

The power and flexibility inherent in Zigbee technology is exemplified by its ability to support over 64,000 devices in star, tree or mesh formations. The technology provides high reliability, self- healing, self-joining networks, with network protocol security encryption, and is designed to operate in electrically noisy industrial environments.

How ZigBee is an improvement on RFID

Whereas RFID is a method of remotely storing and retrieving data using RFID tags and readers, Zigbee goes much further. It is a full- blown telemetry system in its own right, with the ability to provide wireless personal area networking (WPAN) i.e. digital radio connections between computers and related devices, such as sensors. This kind of network eliminates the use of physical data buses such as USB and Ethernet cables. As such, Zigbee it is the ideal system to provide the copper-less warehouse or factory.

One of the key benefits of Zigbee is that, unlike RFID tags, its nodes can relay each other’s traffic, bypassing wired networks completely. In contrast, Wi-Fi devices connect directly to an access point, which is wired to the enterprise network using Ethernet, while Bluetooth devices connect to another wireless device, usually a phone, which acts as a hub.

ZigBee for tracking

When used in a tracking application, Zigbee does not require the read portals or the associated management software that RFID systems do. Moreover, although RFID tags are cheap, the infrastructure required to read and process the data they gather is not. There are some downsides, however: RFID technology is simpler and cheaper than wireless technology at present, but this situation will no doubt change when the greater flexibility, utility and reliability of Zigbee results in its more widespread application.

Global comms protocol

Zigbee builds on the global communication protocol standards developed by the 802.15 Working Group. The fourth in the series of these protocols, WPAN Low rate Zigbee is designed primarily for telemetry applications. It provides specifications for devices that have low data rates, consume very little power and are thus characterised by long battery life. Compared to Bluetooth, another of the 802.15 Group protocols, Zigbee has lower data rates and doesn’t offer such a high bandwidth.

The 802.15.4-based Zigbee is designed for remote control and sensors, which are many in number but only require small packets of data, and in the main, extremely low power consumption for long life. One of the technologies first areas of usage is home automation, where it revolutionising components such as light switches, fire and smoke detectors, thermostats, kitchen appliances, security systems and video and remote controls with its wireless technology.

Building controls

The big plus for consumers – apart from being able to position switches anywhere - is that, with Zigbee designed to enable two-way communications, not only will they be able to monitor and keep track of their domestic utilities usage, but also feed this data to a computer system for data analysis. In addition, consumers will be able to interrogate Zigbee nodes remotely to determine and change the temperature of buildings, or switch on devices prior to arriving home.