【作者】 佟吉钢；

【导师】 陈增强；

【作者基本信息】 南开大学 ， 控制理论与控制工程， 2010， 博士

【摘要】 嵌入式系统是以计算机技术为基础,面向特定的应用目标和环境,同时对功能、可靠性、成本、体积、功耗有严格要求的专用计算机系统。由于它是以软硬件可裁的“量体裁衣”方式把所需的功能嵌入到各种应用系统中,具有高度的自动化、响应速度快等特点,因此特别适合于要求实时和多任务处理的场合。近年来随着电子技术飞速的发展特别是大规模集成电路工艺水平的不断提高,从便携式音乐播放器到航天飞机的实时控制子系统都能见到嵌入式系统的应用。而且其应用范围领域日趋广博、普遍深入到我们日常的工作生活当中,成为不可或缺的必要工具。针对目前在嵌入式系统方而应用热点的一些领域,本文主要围绕着高性能DSP、FPGA及无线传感器网络在设计应用中的一些问题及方法重点进行了研究,主要研究工作包括以下几个方面：(1)当前DSP的使用非常普及,针对迟滞系统的高精度实时控制的实现及语音信号的有效处理,本文选取一款典型的高性能代表性芯片TMS320C6713(225MHz)专门进行了相关的硬件电路设计及软件研究。围绕该芯片设计实现了满足上述目的要求的系统硬件平台,并按照系统中不同的功能模块,设计成各自独立的电路,极大的简化了电路设计及系统调试,并为系统后续功能扩展提供了可能。在软件设计上,深入其应用的核心——实时操作系统(RTOS),研究了可提供底层应用函数接口的RTOS/BIOS主要功能模块构成及应用。为后续DSP芯片内部资源优化配置,更方便灵活地使用DSP芯片打下基础。创新点为设计实现了高性能DSP系统硬件平台,同时将系统各功能模块设计为可自由组装的独立电路模块；并深入研究DSP实时操作系统RTOS及BIOS主要模块的功能与应用。(2)图像及视频加密是当前的一个研究热点,但传统加密算法的设计实现多是以计算机为平台去实现的,很少考虑网络实时环境下的情况。对此本文从实际应用的角度出发,设计了一款网络环境下即插即用型的基于嵌入式系统的实时加密系统,即基于FPGA的网络视频流混沌加密系统。充分利用FPGA的并行处理与使用灵活的优势,对网络视频流进行混沌实时加密,实现了基于Baker映射、Cat映射,Logistic映射和超混沌映射的单一加密、双重加密和随机选择加密多种加密方式。进行超混沌视频加密时,使用VHDL语言编制特定的IP核实现硬件加密。整个系统通过局域网环境下的实际运行测试,系统安全性、稳定性得到了检验。创新点为设计实现了基于FPGA的网络视频流混沌实时加密系统,利用FPGA的优势实现了使用多种混沌加密方式对网络视频流的实时加密。(3)目前无线传感网络的应用较为普遍,但其节点核心处理器的数据处理能力却相对较弱,为此提出了基于FPGA的无线传感器网络节点设计方法。利用FPGA应用的灵活性和良好的并行处理能力,针对不同的开发板分别研究了在其中嵌入单核、双核及多核处理器的实现过程及资源耗用情况。创新点为设计实现了基于FPGA的无线传感器网络节点,并研究了在三种不同FPGA开发板中嵌入单核、双核、多核处理器的具体实现方式。更多还原

【Abstract】 Based on the computer technology, the embedded system is one kind of special computer system, which has strict requirments on its functions, reliability, cost, volume and power consumption, according to the the specific application goal and environment. Since it is well tailored and all needed functions are embedded in the application systems, and thus it has the characteristics of high automation and fast response. Therefore, it is especially suitable for the situation with higer demands of real-time and multi-task. With the rapid development of electronic technology and especial progress in VLSI recently, the application of embedded system can be seen almost everywhere, including portable players and real-time control subsystem in space shuttle. With the applications fields getting wider, the embedded system has become an absolutely necessary tool in our life and work.For some hot research topics on the embedded system, the thesis does some work about the high-performance DSP, FPGA and wireless sensor network. The innovational work is summarized as follows:(1) The DSP is very popular now. For the problems of the high degree accuracy of hysteresis system and the effective deal of voice signal, this thesis selects a typical high-performance chip TMS320C6713 (225MHz) to design the corresponding circuits and software. In order to satisfy the requirments about some problems, the system hardware platform is designed. According to their different system functions, the whole system is divided into different circuit function module, which greatly simplified the design of circuit and debug of the system. It also makes a basis for the latter extension of system function and application research. In the software design, the software core Real Time Operating System (RTOS) is researched. Its main function module and relative application of RTOS/BIOS with the function of bottom application interface is got clear. This work makes a good basis for the inner resource optimization, configuration, flexible use of DSP, and offer a good application platform.The innovation points are that different circuit module with their own function and free assembly is designed and realized; the main function module of real time operating system (RTOS) and BIOS is also got deeply researched.(2) The encryption of image and video is a hot topic, but the traditional encryption algorithms are realized by computer. The situation in real-time network environment is rarely considered. Therefore, an encryption hardware platform in real-time based on embedded system which is a plug and play, is designed. The hardware platform is realized according to practical applications and network environment. It is an encryption system of network video stream based on FPGA. By utilizing the chaotic Baker map, Cat map, Logistic map and hyper-chaotic map, the encryption is realized through single encryption, double encryption and multi-way encryption. According to video encryption in hyperchaos, specific IP core with VHDL was programmed to realize the hardware encryption. For all the above encryption methods, their securities and stability are tested and verified in practical operation.The innovation points are that chaos encryption system in network video stream based on FPGA is designed, the network video stream is encrypted in real-time.(3) The wireless sensor network is widely applied, but its data processing capability of central processor within the node is still limited. Therefore, the node wireless sensor network based on FPGA is designed. FPGA has good characteristics of flexibility and parallel processing capability. For different FPGA development board, different realization methods, including single, double processor or multiprocessor, are embedded into it. The realization of them and the consumption of their resource are researched.The innovation points are that the node wireless sensor network based on FPGA is designed, and the realization methods of single, double processor or multiprocessor in different FPGA development board are also studied.更多还原