Wireless applications are designed to make life easier, but reliability of wireless technology is at times questionable. Further enhancements to the ZigBee protocol are helping the platform find a prominent place in the home. Paul Skelton reports.

Recent industry forays into the expansion of wireless connectivity have highlighted the benefits of many different communication technologies.

ZigBee is growing rapidly in the AV industry – from its incorporation in power meters for homes in New South Wales and Victoria to the implementation of a dynamic learning algorithm developed by Victorian TAFE students that routes messages between devices.

The protocol has many qualities designed to accomplish various sensor and control tasks in ways other technologies cannot. For example, infra-red, as typically found in remotes, is not a two-way communications technology and it relies on line-of-sight connections.

ZigBee maintains two-way communication, offering robust security, self-organising and self-healing networking, scalability to thousands of nodes and multi-year battery life for battery-powered sensors.

It delivers all of this while using wireless radio frequency technology based on the Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 Standard.

Convergent Technologies is the Australian distributor of Control4 products, whose ZigBee applications use low transfer rates of 20kbps and 40kbps.

Technical product manager Alan Chow says the current focus of Control4 is to use the technology in the development of a general-purpose, inexpensive mesh network that can be employed for home and building automation and control.

These applications include smart lighting, advanced temperature control, water and power sensors, and energy monitoring.

“ZigBee protocols are intended for use in embedded applications requiring low data rates and low power consumption – individual devices can run for almost a year on one battery,” Alan says.

“Using ZigBee as a platform means the connectivity can last months or years, and not days. The standard Bluetooth connection, for example, will last a maximum of one day.”

Bluetooth was developed as a wireless headset technology. Networks are limited to eight nodes or fewer, its security is very basic and it is not designed for the command and control applications performed by ZigBee.

A Bluetooth battery follows the recharge model of mobile phones – it needs to be to be recharged almost every day. These factors make Bluetooth unsuitable for most sensor and control applications.

ZigBee Alliance chairman Bob Heile says the technology is experiencing rapid growth. The ZigBee Alliance was formed to promote adoption of the platform throughout the industry. Members of the Alliance include Motorola, Philips, Samsung, Schneider Electric and Siemens.

“We are seeing rapid adoption of ZigBee in home and commercial building automation, industrial areas and lately in the energy sector,” Bob says.

“The energy industry – especially electricity supply – needs new ways of managing in-building energy consumption. This need is driven by a variety of issues: the lack of future generation capacity, the need to reduce greenhouse emissions, and government regulations.

“As these groups investigated their options, they discovered that ZigBee supplied exactly what they were looking for – a way of communicating with in-building systems over an open global standard through a meter or over the Internet and with extremely high security.”

Bob says many large suppliers of meters have announced support for embedding the technology in the products.

“An increasing number of electric service providers are also announcing ZigBee-based programs. The Victorian Government and the State of Texas have included specific references to ZigBee in their energy regulations because of its robust capabilities. As a result, more product manufacturers are planning to market products based on this technology.”

The alliance, which developed ZigBee as a result of Bluetooth limitations, conducts quarterly interoperability events called ZigFests. These events allow member companies to come together under strict non-disclosure rules and test their products with each other before heading into a test house for formal testing.

“Much like any Standards organisation, such as IEEE and the Consumer Electronics Association, ZigBee relies on its member companies to set the agenda on what is important for coverage in the market and for the development of the Standards,” Bob says.

“Having open Standards is essential, but manufacturers also need a way of testing whether their implementations are correct.

The alliance and its members develop tests to ensure ZigBee products operate as promised, allowing customers to buy them with complete confidence.”

The alliance develops awareness of the ZigBee brand. It also co-ordinates market education and awareness events such as developer conferences and ‘webinars’, and tutorial tracks at trade shows.

However, the emerging protocol has had to face stiff competition from the likes of companies with proprietary and non-standard technology – such as Z-Wave, another affordable, reliable and easy-to-use wireless platform.

Z-Wave is also an interoperable wireless mesh networking technology that allows a wide array of devices in and around the home to communicate: lighting, appliances, HVAC, entertainment centres and security systems.

Formed in January 2005, the Z-Wave Alliance is a consortium of companies in home technology dedicated to solidifying Z-Wave as the Standard for wireless home control products. The principal members include Cooper Wiring Devices, Intel, Monster Cable, Universal Electronics and Zensys (owner of Z-Wave).

Z-Wave technology was the recipient of the 2006 Wall Street Journal Technology Innovation Award in the wireless category, the CNET Best of CES Award in the enabling technologies category, and PC World’s 2006 World Class Award, which recognises the 100 best technologies and products of the year.