Bridging the Gap: Extending Bluetooth to Ultra-Low-Powered Equipment

摘要

A new wireless technology extends Bluetooth networks where both ultra-low-power operation and long range are essential. Looking for a challenge? Try designing a communications network that can exchange data wirelessly over a range of several hundred meters, communicate with the external world, and accommodate electronic devices with power consumption requirements on the order of a few microamperes. Current radio frequency (RF) standards such as Hiperlan, DECT, 802.11, Bluetooth, and more recently, ZigBee, cannot simultaneously address all of these constraints. Meanwhile, cable replacement and product enabler issues are driving compliance with wireless standards to ensure that large deployments are profitable. Coronis Systems has opted to create a system called WAVENIS to bridge the gap between standards-based wireless communications and ultra-low-power (ULP) devices. Communications networks using ULP devices are defined by five basic parameters: low data rate (typically ranging from a few tens to a few hundreds of bytes); low operational traffic, which means that connectivity is low; long operating life when battery powered (up to 15 years for the most demanding applications); the ability to connect to the wide area network (WAN), extending the network out from the meshed ULP network; and ULP end points and access points that must be cost competitive. Market demand has driven attempts to meet the challenges and balance the tradeoffs presented by these five competing parameters. Manufacturers are eager to serve ULP applications such as autonomous wireless sensors, automatic meter reading, home automation, home comfort, remote control for industrial use, alarms, and security as well as promising new applications such as healthcare and "smart" devices. Because of the differing technical and economic constraints, Coronis Systems has opted to use two distinct approaches with similar architectures: ULP for end points and Bluetooth/ULP for access points.