By Darrell Dunn
From: cmpnetasia

Yet another wireless connectivity standard will claim the spotlight next week, as the ZigBee Alliance conducts its member meeting at an open house in Berlin, and IC suppliers like Motorola Semiconductor Products Sector (SPS) demonstrate compliance with the recently passed 802.15.4 standard.

"This standard was designed to fit in a market where there are a lot of proprietary wireless solutions right now," said Kristen Law, senior product marketer for 802.15.4 technology at SPS in Phoenix. "This will fit in a low-data-rate market for things like industrial automation and control, logistics management, energy monitoring, motor control, and lighting systems, as well as home networks like security, HVAC, and RF remote control," she said.

The IEEE 802.15.4 ZigBee standard was approved in May, and initial network implementations are expected to be demonstrated in Berlin this week. Interoperability testing is scheduled for early next year, with the first end products expected mid-2004, Law said. Currently there are 50 ZigBee Alliance members, including IC suppliers like SPS, AMI Semiconductor, Atmel, and Philips.

ZigBee is expected to fill a niche for low-cost and very-low-power wireless connectivity -- a notch below Bluetooth implementations -- for equipment that needs battery life as long as several months to several years but doesn't require data transfer rates as high as those enabled by Bluetooth.

In addition to providing longer battery life than Bluetooth, ZigBee can be implemented in mesh networks larger than is possible with Bluetooth. Data throughput of 250Kbits/s can be achieved at 2.4GHz, at transmission distances of 10 to 75 meters. In fact, the success of the standard could throw up yet another stumbling block for Bluetooth, which is seeing its market eroded at the high end by 802.11 wireless LAN and possibly by ZigBee at the low end, said Will Strauss, an analyst at Forward Concepts Co., Tempe, Ariz.

"Bluetooth's reason for being is getting narrower and narrower, while it is also still hounded by interoperability problems," Strauss said. "Right now Bluetooth is kind of a mythical thing, with probably 90% of all Bluetooth shipments being used in wireless headsets to connect to wireless handsets."

The ZigBee Alliance is aiming for a $5 price point for initial market offerings, including software and full hardware bills of materials. "In areas where you're not transferring a lot of data, things like Wi-Fi are overkill, while Bluetooth doesn't have the mesh network capability," Law said.

Motorola believes ZigBee will emerge primarily in pilot installations in nodes numbering in the tens of thousands this year and next, but could reach millions of units by 2005.

However, some analysts said the standard is still too new to warrant hard-and-fast predictions. "Right now it's a technology looking for a market," Strauss said. The 802.15.4 standard details the physical-layer and medium access control (MAC) specification, and offers the building blocks for different types of networking known as "star, mesh, and cluster tree."

The SPS product is designed to support the 2.4GHz band. A standard serial interface can connect the host controller, such as an 8- or 16-bit microcontroller, and enable it to send and receive digitized data packets. The MAC code will be offered for a wide range of Motorola microcontrollers, Law said. A customer could then add ZigBee networking to existing applications by adding the RF modem and porting the MAC code to the host controller.

This story first appeared in EBN, a US-based CMP publication.