【作者】 王东；

【导师】 任广辉；

【作者基本信息】 哈尔滨工业大学 ， 信息与通信工程， 2007， 硕士

【摘要】 由于信息技术发展,信息安全已经成很多重要部门关注的问题。例如:证券交易业务、电话银行业务中账号、密码被截获,军事指挥的语音信息被敌方窃听等。所以普通电话越来越不能适合保密性更高的要求的部门使用,为此开发出高性能保密电话显得非常重要了。本课题提出基于DSP的数字加密电话的设计与实现。首先,实现模拟语音信号的采样,将模拟信号进行数字化转换,然后对采样的数字信号进行压缩编码。硬件设计首先根据语音信号的特点及语音信号的编码方法,提出基于AD73311和AMBE2000语音采集模块。模块能够实现数字语音信号的采集、压缩编码、帧结构分组输出。为数字语音信号的加密奠定了基础,语音采集模块的信号处理延迟满足系统要求。其次,在硬件设计上,主要设计了数字加密电话系统结构,画出原理图和PCB板图,通过对分析数字语音信号处理及传输延迟,回声信号产生的原因,对通话质量的影响,提出了如何采用硬件设置来提高通话语音质量。在SI3016芯片与公用电话网接口电路的设计上,采用SI3016手册推荐电路并且分析了电路可靠性。最后,在硬件上实现加密算法,重点研究了具有代表性的RSA和IDEA加密算法,深入研究了IDEA加密算法的安全性和易于硬件实现的优点,提出了基于IDEA加密算法在DSP上实现对数字语音加密的方法。并且利用CCS开发软件对IDEA加密算法进行仿真,在CCS的Simulator模式下,通过设置DSP的配置信息,优化C程序代码,最后利用CCS系统的Profiler工具测量程序运行指令周期,对算法运行的指令周期数进行了分析,分析结果表明:IDEA加密算法延迟满足系统时间延迟要求,进而验证了IDEA加密算法的工程实用性。更多还原

【Abstract】 With developing of the information technology. Information security has become not to be ignored important issues. For example: Securities transactions, telephone banking account, the password was intercepted by the military command voice messages tapping, Voice communication security needs of the occasion, the confidentiality of telephone set higher requirements. Not ordinary telephone increasingly higher for the confidentiality requirements of the occasion use. That developed high-performance telephone confidentiality is very important. The issues about the based on the DSP of digital encryption telephone design and implementation.Firstly, the simulations of the speech signal acquisition, analog signals to digital conversion. And then, the acquisition of digital signal compression coding. According to the design first speech signal characteristics of the speech signal encoding method, the based on the AD73311 and AMBE2000 voice Acquisition Module. Module to achieve digital voice signals in the collection, coding, a frame structure output. Speech signals to digital encryption laid the foundation for the Acquisition Module voice signal processing delay to meet system requirements.Secondly, the hardware design of digital encryption telephone system structure. Painted drawings and PCB map through the analysis of the speech signal processing and transmission delays. The echo cancels how to use the hardware to improve the quality of voice calls. Design SI3016 chip of PSTN interface circuit. SI3016 manual recommends using circuit analysis and reliability of the circuit.Finally, the implementation of encryption algorithm based on the hardware. Focus research of representation algorithm encryption IDEA and RSA encryption algorithm. In-depth study of IDEA Encryption Algorithm the safety and hardware implementation advantages, Based on the IDEA Encryption Algorithm in the DSP realization of digital voice encryption methods. Development and using of CCS software simulate IDEA encryption algorithm. Simulator in the CCS model, by setting DSP configuration information, optimizes C code. The CCS System tool of Profiler measure procedures cycle. Algorithm running on the instructions of a few cycle analysis and the results showed: IDEA encryption algorithm time delay and system delay to meet requirements then verify the IDEA encryption algorithm in a project.更多还原