Basic Research On Embedded Wireless Sensor Networks

Since the entering of 21st century, with the rapid development of new technology, the muti-disciplinary and cross-cutting area has become a hot research topic. The development and integration of MEMS (Micro-Electro-Mechanical System), wireless communication, embedded system and sensor technology, promoted the emergence and development of wireless sensor networks (WSNs). WSNs are networks of wireless nodes that are deployed over an area for the purpose of monitoring certain phenomena of interest. As a new technology in the field of communication, automation and computer science, it have been researched and applied to many fields including military defence, city management, environment detection and the remote monitor and control of dangerous circumstance.This paper designs a kind of embedded WSNs, which can be used as a platform for deeply study of nodes location, organization, router and energy management, etc.This paper gives the system hardware and software design of mbedded WSN node. After the consideration of performance, power-comsumption and cost, the hardware design of embedded WSN node is achieved by employing the popular ARM core microprocessor chip AT91SAM7S256, RF transceiver CC2420, GPRS module MC39i, temperature sensor TM05 and accelerometer ADXL202. The system software platform is consisting of Real-Time Operation System FreeRTOS, ZigBee and TCP/IP stack. After the design and implement of system device driver and application software, the function of communication between RF modules, remote data transmission through GPRS module and information collection of sensors are realized. The data center software, which is used to receive the data of remote WSNs, is designed by using VB.NET. The overall design of embedded wireless sensor networks, including hardware and software, is illustrated in detail.Finally, the performance of embedded WSNs is verified through the tesring of the fuctional modules. The embedded WSNs, this paper presents, have the many virtues such as high-proformance, power controllable, good portability and updatable. It not only can be used as a platform for deeply study of WSNs, but also provides a referrence for the application development in many fields.