Driven by the demand for “green” technology and better use of power, a new generation of extreme low power wireless networks is being developed for use in machine to machine networks, for industrial and control applications, as well as for health, security and other purposes. This article is about this new approach towards truly wireless networks ? without any network cables or power lines.
By using systems that require very little power, it is possible to develop wireless networks that can last longer than their batteries and therefore require little or no maintenance over the life of the device, or a device that does not require any batteries at all, instead, using energy harvesting to provide the power required.
Before the era of wireless sensor communication, low-power was synonymous to low current consumption. The lower the milli-amp figure, the better the device was at low-power operation. It was all about how many or rather how few milli-amps the electronics consumed.
Furthermore, when the device did not need to communicate, it was turned off, to be awoken when an alarm situation was raised or a periodic status update was called for. This technique is called duty cycling.
Current consumption ? milli-amps ? and duty cycling are still important in wireless sensor networks. However, low current consumption is only part of the solution.
Five other essential issues are key to developing low power Wireless Sensor Applications
1.Low-power Wireless Mesh Routing:
One of the most dramatic differences between wireless sensor communication technology and other well known wireless technologies is the ability of sensor nodes to forward messages from other nodes further down a communication chain. This is called mesh routing or multi-hop networking. Mesh networking is an effective and reliable solution to span large infrastructures in a reliable wireless fashion, beyond the range of what a single wireless link can do.