Design And Implementation Of Wireless Sensor Networks Platform Based On6LoWPAN

Wireless sensor networks is a multi-hop ad hoc networks which is consist oflarge number of sensor devices arranged in the control environment throughwireless communication approach， it has the capacity of data collection,processing and transmission. The address space of the fourth version of thenetwork protocol IPv4has not be able to meet the growing demand fornetworking equipment, while bringing the IPv6protocol that has a128-bitaddress space into the wireless personal area network will greatly promote thedevelopment of wireless sensor networks.6LoWPAN technology is born in thisbackground, it breaks down the barriers to using IPv6on low-power,source-limited embedded devices in low-bandwidth wireless networks.The background and current situation of the WSN is first introduced in thispaper, and then the important technical support: IPv6protocol and PHY andMAC layers that are specified by IEEE802.15.4protocol is introduced. Since themaximum transmission unit of IPv6is up to1280bytes, while the MAC is only127bytes. So to make the IPv6packets transmit on the underlying devices, anadaptation layer which shield the differences between upper and low er must beinserted between the IP and the MAC layer. The functions of the adaptation layerare studied and the data frame format, fragmentation and reassembly of theadaptation and the context-based header compression algorithms:LOWPAN_IPHC and LOWPAN_NHC using in this project are detailedanalyzed.Reference to the superiority of the Linux operating system and consideringthe advantages, disadvantages of some6LoWPAN platform architectures, a newarchitecture which integrated6LoWPAN in the Linux kernel is designed and thecode of it is analyzed. Micro2440ARM development boards and ATMELAT86rf230RF chip which is compatible with IEEE802.15.4are used in the entiresystem hardware. Finally, to build the entire6LoWPAN platform, the Linuxkernel is ported as software development environment and the root file system ismade. Basic functions of the6LoWPAN stack are tested in simulation，the resultsshow that the stack is realized in Linux operating system.