معماری شبکه حسگر بی سیم Polytropon : یک پلتفرم متن باز و مقیاس پذیر جهت شبکه های هوشمند (smart grid)

This article presents the overall design methodology followed for an open source Wireless Sensor Networking platform that aims at the remote energy monitoring of home appliances in real-time using web technologies. This platform can be a paradigm for building open source devices for smart metering and home energy management by controlling electric loads, thus contributing to the development of the smart grid infrastructure. The Polytropon platform is designed as a research tool for experimenting with the various hardware and software components that can be integrated in the nodes, by following the open source hardware and software guidelines for development.

2.  Hardware Architecture of the Polytropon platform

An integrated wireless sensor platform has been designed and developed (named hereafter Polytropon) suited for applications that can be integrated in the backbone of the smart grid. Two successful open source platforms, the Arduino [14] and the Texas Instruments Launchpad [15] have been utilized for the extraction of the final specifications that follow the open source standards for the distribution of the developed software and hardware. The main parts of this platform are a wireless sensor node and a gateway node. The gateway is based on a Polytropon wireless sensor node that has the role of the coordinator of the WSN realized combined with the Beaglebone Black [16] open source platform that integrates a high processing power microcontroller and a single-chip solution for TCP/IP networking.

A block diagram of the Polytropon platform is given in Fig.1. The important characteristics that this platform integrates can be summarized to the following:

• Two Ultra low power consumption microcontrollers
• New non-volatile RAM based on FerroElectric technology (FRAM) that provides robustness combined with extremely high speed and power consumption compared to the common FLASH technology
• Embedded electric power metering using a dedicated IC
• Unique 64-bit EUI identification for the MAC address
• Embedded encryption capability based on AES128/256
• Embedded Real time clock peripheral
• Embedded backup power source
• Sub-GHz RF modem with IEEE802.15.4 for the MAC layer of the wireless network
• Capability for 6LowPAN networking protocols
• Compatibility with board extensions for the Arduino Platform-Shields
• Compatibility with board extensions for the Launchpad Platform-Boosterpacks