2JIN Guangyao, LU Xiaoyi. An indoor localization mechanism using active RFID tag [C]// Proceedings of the IEEE International Conference on Sensor Networks, Ubiquitous, and Trust-worthy Computing. Seoul, Korea, 2007: 3943.
3DEITEL H M. C# for experienced programmers [M]. Beijing: Publishing House of Electronics Industry, 2003:145 -208.