Smart metering is a very exciting hot topic nowadays. It is the joint interest of utility and consumers to implement an AMI (Advanced Metering Infrastructure). There are many different ways to implement an AMI, in my work I have considered the model developed by CASON Engineering Plc. CASON uses wireless communication technology in the impelementation of AMI. The objective of the company is to cover as wide geographical area as possible with highest available service level using minimal number of cheap devices. CASON recommends its DIWICON-U product portfolio.
My task was to develop the firmware modules of coordinator, router and end device which are the main components of an AMI. The smart meter is the end device, the router receives and relays data, and the coordinator collects data, sends them to the server and sends acknowledgements to other devices.
I use a CC1110 SoC (System On Chip) for the wireless communication which can communicate in 868 MHz ISM (Industrial, Scientific and Medical) band. This chip has all the functions which are required in an AMI. Due to its low energy consumption modes it is possible to use battery operated end devices. The radio registers can be accessed directly and have rich setup options. Since the chip can handle different sub gigahertz frequencies, the firmware can be used with minimal changes at other frequencies.
I use the radio protocol ZigC developed by CASON, which is optimized for AMI solutions. The major advantages of ZigC are the simplicity, low power consumption, and the remote firmware update capability. Its success is proved by hundreds of installed 2.4 GHz operated devices.