Research And Implementation Of Wireless Voting System Station Based On ZigBee Technology

The electronic voting system is used for the calculation of the voting results in activities of voting, answering, and opinion polls. Two categories are included in the voting system: the wire voting system and the wireless voting system. Compared with the wire voting system, the wireless system enjoys the advantages of no-wiring, and easy to move etc... However, the transmission distance of the wireless voting system is shorter than that of the wire voting system. With the increasing application of the wireless voting system in meetings and multimedia teaching, people raise higher requirements on the voter's power consumption, cost, signal intensity strength and transmission distance. In taking the good points of both the wire voting system and the wireless one, the thesis proposes a base station design plan of wireless voting system combining the advantages of industrial Ethernet technology and ZigBee technology. It aims to improve the wireless voting system's disadvantages of short transmission distance, weak indoor signal and high power dissipation.The thesis firstly compares the advantages and disadvantages of ZigBee technology with various wireless technologies, and illustrates the development status of the voting system both at home and overseas. Then, the overall structure of the system and the design plan of the base station are introduced based on an in depth study on the ZigBee technology. Centering on the AT91SAM7x256 ARM chip and the functional modules of Ethernet interface, wireless communication and power supply, the hardware design of the base station and the experimental equipment are completed. Considering the functional requirements of the base station system, theμC/OS-II is chosen as the operating system for its advantages of small code amounts and sound functions. Meanwhile, the transplanting of the real-time operating system on the control chip is realized and the implanting of LwIP and ZigBee protocol stack to the TCP/IP protocol stack is completed. Finally, the Ethernet device driver and wireless module device driver are programmed, through which the ground data exchange function is realized. To meet the application demands of the voting system, the upper layer application softwares, which includes internet management, data processing and base station management, are developed.The testing of the base station, host computer and the voter are done in the lab. The transmitting of the commands and data of the remote centre to the voter is completed, and the transmitting of the voting results back to the remote centre is successfully realized. It's also proved that, constructing more than one base station under the same circumstance can increase the signal coverage area.