Study On Wireless Sensor Networks System Based On New Magnetic Field Sensor

In recent years, the reseach for wireless sensor networks(WSN) increasingly penetrates into a variety field of applications and develops rapidly. The article analyzed the wireless sensor network system characteristics, advantages and the actuality of WSN's development in detail, and on the basis of integrating characteristics of new amorphous alloys magnetic sensor and extensive prospects for applications, proposed a assumption of building a wireless sensor network and finally realized in both hardware and software aspects.The main study of the article is as follows:The article analyzes the structure characteristics of common sensor network and according to the actual needs of research proposed a system model of large number of ordinary nodes with a base station node . This model possess a general character and expand easily. Articles designed ordinary nodes and base stations node from both hardware and software aspects, actualized the entire system.In terms of the thought of modular design in hardware,ordinary nodes and base stations node are based on the same processing module and wireless communications module.The ordinary nodes have sensor modules used for information collection, the base station node have a interface module communicated with computer but not the sensor module. Processing module used the processor chip of 8-bits AVR Series Atmega1281 for node hardware resources management and tasks scheduling; wireless communication module used radio transceiver integrated chips,CC1000 worked in the ISM band (433 MHz),for the communications among the nodes. Ordinary nodes used amorphous alloys magnetic field sensor as sensor module to acllect the information of environmental field. The base station node communicated with the computer through the RS232 serial bus after the chip voltage was converted.In node software aspects, there are popular TinyOS embedded operating system. Based on the components thinking of TinyOS, nodes programs make up of different functional components, such as the main components, communications components, analog-digital conversion components and routing components, in order to complete the corresponding function. Components codes used NesC language to be propitious to realize components programming. The part of data management analyze the shortcomings of traditional database systems. Then design the distributed data management system TinyDB,which is based on wireless sensor network, and the client for data query, selecting and gathering. TinyDB realized by java language.Wireless magnetic field sensor networks passed program simulation and experiment, the communication functions were normal and can be achieve real-time monitoring of magnetic field information. System has good versatility and expansibility, can be used into many fields,for example: to detect parking spaces and to monitor the surface movement.