目标跟踪是无线传感器网络的一个重要应用。为了验证和测试算法性能,缩小理论与实际的差距,必须构建相应的物理平台。介绍了所构建的无线传感器网络目标跟踪平台,其硬件包含超声波传感器、被动红外传感器和Micaz节点组成的无线传感器网络,而软件包括上层监控系统及下层节点嵌入式程序。针对节点资源十分有限的情况,提出了一种基于最小均方估计误差的目标跟踪协同调度算法,并在物理平台上成功实现,实验表明该平台能有效地跟踪无线传感器网络内的移动目标,并在保证跟踪精度和跟踪实时性的同时,采用了双重唤醒/休眠机制来延长网络寿命。
Target tracking is the most typical and challenging application of wireless sensor networks (WSN).In order to prove and test algorithm performance and reduce the existing gap between the established theoretical results and practical problems,the real test-bed should be built.The WSNs target tracking platform contains the hardware and software.The hardware consists of ultrasonic sensors,passive infrared(PIR)and Micaz nodes,while the software includes the graphical user interface(GUI)and node embedded program. Aiming at the limited node resources and working in a dynamic environment,a target tracking collaborative scheduling algorithm based on minimum mean-square estimation error is proposed and successfully realized.The experiments show that moving targets can be efficiently tracked within this test-bed.With the purpose of saving energy consumption and enhancing real-time tracking performance,a double wake-up/sleep mechanism is adopted to extend network lifetime.