【作者】 胡冰；

【导师】 罗武胜；

【作者基本信息】 国防科学技术大学 ， 仪器科学与技术， 2010， 硕士

【摘要】 无线多媒体传感器网络(WMSNs)是在传统无线传感器网络(WSNs)的基础上发展起来的具有音频、视频、图像等多媒体信息感知功能的新型传感器网络。同只具有简单环境数据采集功能的传统无线传感器网络相比,无线多媒体传感器网络能实现细粒度、精准信息的环境监测,在军事上具有非常广阔的应用前景。基于对无线多媒体传感器网络未来广阔应用前景的认识,尤其是考虑到其战场环境立体监测中的巨大应用价值,论文在国家自然科学基金项目“适合于WMSNs的图像压缩算法及多节点协同图像传输技术研究”(No.60872151)的资助下,围绕无线多媒体传感器网络节点即图像侦察传感器中的关键技术开展研究,主要完成了以下几个方面的工作:1、全面综述了多媒体传感器网络的优势,介绍了图像侦察传感器的缺点及其军事应用,总结了多媒体传感器节点的国内外发展现状。2、研究了RSA+RS算法,以实现图像信息安全、可靠传输。安全性上,选取加密算法RSA,叙述其原理,研究其快速实现算法;纠错算法上,选择RS算法,对其进行了Matlab仿真及分析。最后两种算法共同使用时,用Matlab仿真分析了它们的使用前后顺序。结果表明实际运用时,先进行RSA加密再进行RS编码不仅计算量小,而且误码率也较低。3、探讨了适用于传感器网络的无线传输方法,然后对它们进行比较分析。选择了基于Nrf2401的无线传输方式,并对Nrf2401进行了深入研究与实验。结果表明该无线模块实际传输速度为156kbps,传输距离为32米左右,与理论分析相符合,适用于图像侦察传感器。4、介绍了双正交重叠变换(LBT)的基本原理和LBT的二进整数实现算法和定点实现算法。分析比较了定点LBT和二进整数算法,确定定点LBT更适合无线多媒体传感器网络。提出了定点LBT的DSP并行实现方法,充分考虑行列变换的结构特点,设计了任务分配方式,进行了具体仿真实验。结果表明上述DSP并行实现方法较好的解决了无线多媒体传感器网络中图像压缩实时性问题。5、设计了一种图像侦察传感器。该传感器用OV9650采集图像信息,以DSP芯片TMS320C6204为处理器,Flash芯片HY29LV160为系统程序代码存储器,SRAM芯片CY7C1049DV33进行数据流的缓存,无线传输芯片Nrf2401用于信息传输。更多还原

【Abstract】 Wireless Multimedia Sensor Networks (WMSNs), developed from traditional Wireless Sensor Networks (WSNs),is a novel sensor network integrating sensation functions of multimedia streaming (e.g. audio, video, image).Compared with traditional WSNs which can only measure simple scalar physical phenomena,Wireless Multimedia Sensor Networks are able to ubiquitously retrieve multimedia content such as video, audio streams and still images.Potential applications of Wireless Multimedia Sensor Networks span a wide spectrum to military.Wireless Multimedia Sensor Networks have broad application foreground in military, especially in three-dimentional monitoring in battlefield.Supported by the National Science Foundation of PR China“Image compression algorithm and its multi-nodes cooperative transmission strategy for wireless multimedia sensor networks”(Grant No. 60872151), this dissertation concentrates its attention on the key technology of image scout sensor. The main contents and contributions of this dissertation are as follows:1. The advantages of multimedia sensor are comprehensive reviewed, the shortcomings and military applications of the image scout sensor and the development of multimedia sensor node at home and abroad are introduced.2. The RSA and RS algprithm are studied to relize the security and reliable transmission of image information. First, the security algorithms are analyzed and compared to choose the RSA algorithm and study its optimization; then the error correction coding algorithms are analyzed and compared to select the RS algorithm and study its optimization and simulate it by matlab; finally , the two algorithms are used and simulated to decide the their order.The results show that during information processing, first RSA encryption and then RS error correction coding not only has a relatively low error rate, but also processes faster .3. The wireless transmission protocols of sensor network are analyzed to choose the wireless transmission chip of nrf2401 for WMSNs, then the experiment research of nrf2401 is taken, the result of the experiment show that the actual transfer rate of nrf2401 is 156kbps and transmission distance 32 meters. Consistent with theoretical analysis, the experiment shows that nrf2401 is appropriate for image scout sensor4. The principle of LBT and binary LBT and fixed-point LBT are introduced and compared, then the DSP parallel processing based on LBT fixed-point algorithm is proposed and the experiment is taken, the result shows that this treatment effectively solve the problem of real-time image compression in WMSNs.5. A new image scout sensor is designed.The sensor has the OV9650 for image information acquisition, DSP chip TMS320C6204 for processor, Flash chip HY29LV160 for the system code memory, SRAM chip CY7C1049DV33 for data stream cache, nrf2401 for information transmission.更多还原