Wireless Automation System Based On The ZigBee Technology Design For The Railway Container Terminals

During the "10th Five-Year Plan" period, China's rail container transport system focused on strengthening the container terminals in Guangzhou, Shanghai, Chengdu and other 12 cities with advanced levels. In the latest published "11th Five-Year Plan", the Ministry of Railways will also continue to promote the container terminal logistics center building. Therefore, it is very necessary to construct modern railway container terminals for highly efficiency and the share of the resources.However, the current buildings in the railway container terminals remain relatively backward. In the railway containers terminals, because of the constant movement of the container trucks and loading facilities as well as various mechanical wiring restrictions, mostly we use wireless phones or sending a message to communicate. The communications quality and the communication security are not guaranteed. The 802.15.4 working group defined the ZigBee wireless connectivity technology, and this technology has very low complexity, low-cost, low consumption and low rates and can be embedded in a variety of equipments. It is appropriate to be used in the industrial control area.First, the current communication problems of the railway container terminals' automation system are analyzed in this paper, combining with the characters of the railway container terminals, and the ZigBee technology is selected to realize the communication of the wireless end devices and the control center in the railway container terminals through the analysis and the compare of a variety of wireless connectivity technologies, and the ZigBee mesh network is formed. Each part's function is analyzed, and then the railway container terminals' functions are renewably designed combining with the ZigBee technology such as the end devices, the entrance door and the control center. In order to improve the efficiency of the container trucks and dispose the loading tasks to the nearest container trucks, containertrucks' position can be location estimated. Several different wireless position estimation methods are compared, and the way of comparing the magnetic field intensity is selected according to the needs of the railway container terminals. Container trucks can be location estimated in the regional road of the railway container terminals through amendment the error by the road map and setting the RF fields. Based on the use requirements and the characters of the ZigBee technology, the wireless network layout is designed. The data stream of the entire wireless network is calculated for the feasibility of railway container terminals' wireless network stably working. Finally, PIC18LF4620 of the Microchip Company is chosen to the vehicle system to design the hardware circuit diagram, and the application as well as the interface program is designed.