Research Of Key Technologies For Low Power Wireless Meter Reading System

Since Premier Jiabao Wen put forward the concept of "Perception of China" in 2009,the technology of Internet of Thing has developed in a great speed.The Internet of Thing is widely used in intelligent industry,intelligent transportation,smart grid,smart home,etc.Smart Utility Network is a typical application of the Internet of Thing.By adapting certain wireless communication technologies,the Smart Utility Network are able to gather monitoring data from intelligent meter reading terminals and store them into the collecting center.After collecting data,the collecting center will go a step further by sending the collected data to operation control department by way of other wireless or wire communication technologies.In this thesis,the core of Smart Utility Network,namely,wireless communication technology,is studied.A protocol stack platform based on IEEE802.15.4e LE network is designed.After the design of platform,this thesis carried out embedded software development and hardware test on this platform and realized the reliable data collection of Smart Utility Network.To be more specific:First,this thesis studied wireless sensor network technology,because an Smart Utility Network is a kind of data collecting system based on wireless sensor network in nature.In this part this thesis analyzed wireless sensor network structure,node structure and network protocol stack in details.Second,the MAC sub_layer protocol based on LE network is developed and designed via software.The MAC layer management entity in LE network provides MAC layer management and the database maintenance function of the inherent object.Moreover,the entity provides two kinds of service:MAC layer management service interface and MAC layer data service interface.Combined with the service provided by MAC layer,the design is carried out and emphases are put on the configuration of the PIB value of MAC sub_layer in the LE network,channel access on the basis of CSMA/CA architecture,the design of packet sending process based on CSL unicast transmission,the function of packet confirmation-retransmission and so on.Premised with wireless meter reading system data collecting function,LE network with its special awakening dormancy mechanism enable nodes to operate with considerable low duty cycle,which in turn decrease the nodes' power consumption while increase their the service lives.Finally,a protocol stack platform based on LE network was designed in this thesis.Every node in the Smart Utility Network operates on a four-layer protocol which contains physical layer,media access control layer,network layer,application layer.This thesis analyzed the functions of physical layer,MAC layer and network layer,implemented software design and provide the clients with network layer interface to facilitate the development of upper layer applications.This protocol stack enable nodes to realize Smart Utility Network data collection function via network reliably and with good performance in real-time property.In order to verify the feasibility of wireless meter reading system based on LE network,this thesis operate LE network protocol stack program on the hardware platform composed of MSP430+CC2420.Functional and performance verification are implemented and the test results show that the nodes in this system can send packet abiding strictly by LE network communication mode and satisfy low power consumption,high reliability and other key requirements at the same time.