【作者】 李丽平；

【导师】 杜晓通；

【作者基本信息】 山东大学 ， 控制科学与工程， 2011， 硕士

【摘要】 传感器技术、微机电系统、现代网络和无线通信等技术的进步孕育了无线传感器网络。无线传感器网络由部署在监测区域内大量廉价微型传感器节点构成,通过无线通信的方式形成一个多跳自组织网络。无线传感器网络扩展了人们的信息获取能力,将客观世界的物理信息同传输网络连接在一起,为人们提供最直接、最有效、最真实的信息,具有十分广阔的应用前景。不同的传感器网络应用关心不同的物理量,对系统的要求也不同,其硬件平台、软件系统和网络协议有很大的差别,这就要求节点上的系统必须具备很好的通用性、移植性和较低开发难度,以满足不用的应用要求,引入嵌入式实时操作系统可以很好地解决这一问题。本文以实验室开发的基于Microchip公司的PIC24系列微处理器的嵌入式实时操作系统为软件开发平台,以无线传感器网络通用节点系统的设计为主要内容,阐述了其具体的技术和相关实现的方法。首先,研究了嵌入式实时操作系统的源代码,对操作系统中消息机制进行了优化。其次,由于PIC24系列微处理器内部闪程序存储器的特殊读写性能,在操作系统中加入了内存管理优化方案,方便用户直接读写闪程序存储器。再次,在优化了的嵌入式实时操作系统的基础上,结合无线传感器网络的体系结构以及操作系统任务划分和消息传递机制,根据协议栈的划分,采用分层设计的思想,以屏蔽各层的内部实现,提供通用接口为目标,提出了无线传感器网络通用节点系统的设计方案。最后,针对工程应用中的两个实例,结合具体的软件设计过程,充分阐述了如何方便快捷的在无线传感器网络通用节点系统平台上进行软件的设计和实现。通过两个工程应用系统的成功运行,验证了无线传感器网络通用节点系统具有良好的稳定性和可靠性。可以看出,在无线传感器网络系统中引入嵌入式实时操作系统,将系统做成通用的平台,大大降低了应用程序的开发难度,加快了开发速度,降低了成本,并有效地提高了系统的稳定性、可靠性、可移植性和可扩展性。更多还原

【Abstract】 Sensor technology, micro-electromechanical system, modern network and wireless communication technology are integrated into the Wireless Sensor Network(WSN). The WSN, which is constructed of massive miniature sensors deployed in the monitoring region, is a self-organizing network using the wireless jumps relaying way conmmunication. The WSN expands people’s ability of accessing to information, and makes the physical information of the objective world and the transmission network together, which provides people with real information of most direct and effective. So it has a very broad application prospect. With the different applications, the WSN has different hardware platforms, software systems and network protocols. Thus, the nodes system must have good generality, transportability, and low developing difficulty to meet the different requirements. And the embedded real-time operating system can solve this problem well.In this thesis, using an embedded real-time operating system based on PIC24 family microprocessor which is developed by Microchip company as the software platform, a WSN general nodes system is designed, which has the characteristics of generality, transportability and expandability.Firstly, the source code of the embedded real-time operating system is studied, and the optimization about the message mechanism is put forward.Secondly, because of the internal flash program memory’s special read and write performance of the PIC24 family microprocessor, an optimized scheme about the memory management is developed in the operating system, which contributes to operate the flash program memory.Thirdly, based on the optimized embedded real-time operating system, the WSN general nodes system is established, which is conbination of the WSN architecture and the task and message mechanism of the operating system. Referring to the WSN protocol satck, adopting layered srtucture design, the designed WSN system is aim for shielding the software realization of each layer and providing interfaces for them.Finally, taking two projects as examples, the convenient and efficient programming based on the WSN general nodes system platform is illustrated by giving the detailed software code.The successful running of the two projects shows that the designed WSN general nodes system is of good stability and reliability. It is observed that developing WSN system based on the embedded real-time operating system can greatly reduces the difficulty of designing application program, accelerates development speed, lowers the cost and enhances the system’s stability, reliability, transportability and expandability effectively.更多还原