Design And Implementation Of Multifunctional Sense Node Complying With IEEE 802.15.4-2011 Protocol

Warehouse material storage is an important part of the logistics system,which is an important part protecting the material from the production to consumption.If you can obtain the physical environment,motion state and location information of material in the storage process,which would have a very important guiding significance.Wireless Sensor Networks(WSN)use sensor technology and wireless communication technology to realize the transmission and processing of data in the network,which have a very important application in the material storage and other fields.Ultra Wide Wideband(UWB)technology has the characteristics of low transmission power,anti-multipath and good confidentiality,because of its high temporal resolution,therefore it would be a good solution to use UWB for distance measurement in order to achieve precise positioning.The thesis analyzed the status of positioning products based on UWB and the shortcomings of warehouse material storage,and designed and implemented a multi-functional sense node circuit and application software complying with IEEE 802.15.4-2011 protocol.The main contents of the thesis are as follows:(1)On the basis of analyzing the function and performance requirements of wireless sensor networks and the application scenarios,the thesis processed the system scheme of node circuit,designed MCU module,UWB transceiver module,sensor module,interface module and power module,analyzed the working principle of the node and tested the function of the node circuit.The results shows that the UWB signal output by the node can meet the requirements of FCC and ensure low power characteristics.(2)Based on node hardware platform above,the thesis designed the software of node,including sensing the temperature and humidity,the light intensity and the three-axis acceleration of the node,the UWB signal transmission and reception and ranging between two nodes.The thesis also designed the working mode for the terminal node,the routing node and the sink node respectively,and the host computer program storing,processing and displaying the node data in the network.(3)The thesis tested the performance of the node including node circuit performance test,node sensing function test and life test,built a minimum network system to achieve network testing combined with the host computer program.The test results show that the nodes can attain the ambient temperature and humidity,the lightintensity and the three-axis acceleration of the nodes.The node has an indoor communication range of 26 meters,and ranging accuracy is 15 cm between two nodes,which ensure the multi-functional characteristics of the node.The combination of sensor technology and UWB technology in warehouse material management system will improve the efficiency of warehouse material management,reduce the labor intensity of warehouse management personnel,and bring convenience to logistics management.