共查询到18条相似文献,搜索用时 187 毫秒
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一种保密通信系统的研究 总被引:1,自引:0,他引:1
基于混沌同步的保密通信方式相比传统保密通信方式有很大的优势,发展前景光明。通常混沌同步保密通信方式用混沌掩盖来实现,需要两个信道,其中一个信道传输混沌同步信号使系统保持同步,另一路则传输用混沌信号掩盖后的保密信息。在频谱资源日益紧张的情况下,由于这种通信方式对于信道资源的利用率相对较低,因此经济效益较差。本文提出了一个新的系统,用一个信道轮动传输信息和同步信号,对系统进行了详细分析,重点研究了系统传输的时隙分配并给出了仿真验证,证明了该系统能极大地提高信道利用率,同时对该系统的实际应用作了详细分析。 相似文献
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设计了一种限幅特性非线性三阶自治混沌保密通信电路系统.该系统利用串联同步三阶自治混沌电路进行信号混沌遮掩保密通信.有用信号隐藏在混沌参数中,混沌复合信号作为传送信号,在发送端和接收端之间传送.利用接收端响应系统与发送端驱动系统达到同步,可无失真地将有用信息信号检出.该方法设计简单,易于实现,并且同步速度快,实现了高质量的信息保密传送,具有很好的可行性. 相似文献
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一种超混沌保密通信方案与数字信号处理器实现 总被引:3,自引:3,他引:0
提出了一种基于振荡器耦合实现超混沌保密通信的新方案。在两个RC振荡器耦合产生超混沌信号基础上,构建一个包括信息在内的非线性耦合环路,实现对信息的加密与解密。对其混沌动力学行为进行了分析,包括分岔和最大Lyapunov指数。利用数字化处理技术,对连续时间系统作离散化处理和变量比例扩张变换,最后给出了用数字信号处理器来实现该方案的设计原理与硬件实现结果。 相似文献
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一种语音混沌保密通信方案的研究与硬件实现 总被引:7,自引:0,他引:7
在硬件实验研究的基础上,建立一种环形蔡氏电路,提出用环蔡氏电路实现语音混沌保密通信的一种闭环逆系统方案,其特点是利用环形蔡氏电路的单向耦合原理,通过反馈的方法形成一个包括有用信号在内的极联闭合环路,从而实现改善端与接收端之间混沌系统的严格同步而不受有用信息调制的影响。理论分析与硬件实验结果证明,该方案同现有的其它混沌通信方案相比较,具有非线性失真小、保真度高的优点,完全能够满足传送语音信号的要求。 相似文献
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一个混沌保密通信方案的改进 总被引:5,自引:0,他引:5
对文献[1]中的一个方案作了改进。用混沌映射信号作保密通信系统的调制载波,对待加密传输的信息信号进行调制,不需要用其它混沌同步方法,利用模运算在接收端直接完成混沌载波的恢复,从而恢复信息信号;为了更好地隐匿信息信号特征,借鉴混沌掩盖对信息信号幅度进行限制,使密文完全随机化。仿真结果表明:该加密系统加密效果好,且能抵御密码分析。 相似文献
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提出一种使用时滞超混沌M—G模型加密图像信息的保密算法,由于系统是基于参数辩识的,所以使得系统不需要混沌同步也可以实现混沌的保密通信,同时本算法引入位图像加密的思想,并对加密图像信息进行加密前处理,使得图像信息能够应用M—G超混沌模型进行加解密。此系统结构简单,实用性强,不需要混沌同步。试验和理论分析表明加密效果是令人满意的。 相似文献
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提出了一种利用时空混沌同步的随机密钥的数字保密通信方案,时空混沌输出作为加密和解密的钥匙序列,混沌驱动信号与密文序列混合传输,在接收端解密前首先恢复混沌驱动信号,然后恢复时空混沌加密序列。最后的仿真实验结果证明了该方案的合理性。 相似文献
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首先采用Lyapunov稳定性理论证明了可以用三变量反馈实现两个N-涡卷超混沌系统的同步;然后将反馈控制与小波变换相结合,即此时发端系统的发送信号不是直接被发送,而是进行小波变换去掉细节信息,重构后再发送到收端,收端将该接收信号作为反馈信号,也可以使两个N-涡卷超混沌系统达到同步。仿真实验证明了上述结论并进一步表明,对部分吸引子,用一个信号经小波滤波后的结果作为反馈变量就能实现同步。在相关文献的基础上,减少了反馈变量数,节约了信道资源;同时,传送信号由于高频成分被滤出而成为非完整的混沌信号,不仅进一步节约了信道资源,系统的保密性也得到提高。 相似文献
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Zhiguo Shi Songjie Bi Hongtao Zhang Rongxing Lu Xuemin Shen 《Wireless Communications and Mobile Computing》2015,15(10):1456-1470
In this paper, we propose a synchronization scheme based on an improved auxiliary particle filter (IAPF) for chaotic Colpitts circuit and conduct an experimental study on the synchronization performance with application to secure communications. Specifically, with the synchronization scheme, when the chaotic signals generated by an analog Colpitts circuit are transmitted through a nonideal channel, the distorted signals are processed digitally by the novelly designed IAPF at the receiver, in order to obtain the synchronized signals of the transmitter circuit. Experimental results indicate that synchronization can be achieved over both the additive white Gaussian noise channel and the multipath fading channel with low signal‐to‐noise ratio, even if there exist severe circuit parameter mismatches between the transmitter and the receiver. Furthermore, a chaos‐masking secure communication system is constructed and verified over both the additive white Gaussian noise channel and the multipath fading channel, and the bit error rate is evaluated versus different signal‐to‐noise ratios and symbol periods. It is shown that the achievable bit error rate can reach the order of magnitude of 10 − 4 without error correction coding techniques. In addition, security analysis demonstrates that the proposed chaotic secure communication system is resistant to the brute‐force attack. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Abdelkader Senouci Abdelkrim Boukabou Krishna Busawon Ahmed Bouridane Achour Ouslimani 《Circuits, Systems, and Signal Processing》2015,34(2):393-418
This paper proposes a chaotic communication approach using indirect coupled synchronization scheme with high power encrypted signals. The proposed scheme is carefully designed so that the encrypted signal does not deteriorate the synchronization unlike in traditional communication methods. The synchronization problem is solved using observer-based controller. The advantages of this approach are the general and systematic feedback observer design methodology suitable for convergence rate of synchronization; flexibility in selection of chaotic signals for cryptosystem secure key generator; and improvement of the frequency-domain characteristics of the transmitted message. Computer simulations show that the synchronization between the transmitter and the receiver is more robust for different amplitude values of the information signal, even in the presence of external disturbances. 相似文献
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Yu Zhang Ming Dai Yiman Hua Gonghuan Du 《Electronics letters》1999,35(24):2087-2089
A new secure digital communication scheme is presented which is based on hyperchaotic synchronisation. The message is masked and easily recovered. The chaotic masking signal shows strong randomness. The length of the secure key is calculated to be >200 bit. The security of speech communication is significantly increased 相似文献
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利用混沌同步进行加密是当前信息安全的一个热门研究领域,它不但具有良好的实时性,而且可以有效地避免混沌密钥序列的周期性,其主要难题是如何传输混沌同步信号。提出一种数字音频的混沌加密方案,通过把音频信号的冗余信息自适应地替换成混沌同步信息,从而有效地解决了混沌同步信号的传输问题,并在解密时获得容许误差范围内的混沌同步,进而恢复出密钥序列进行解密,最后将丢失的冗余音频恢复得到最终解密音频。最后以二维超混沌映射为例,通过数值仿真说明该方案的有效性。 相似文献
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《Quantum Electronics, IEEE Journal of》2010,46(3):279-284
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Non-coherent ultra-wideband (UWB) receivers require no channel state information for demodulating the received signal. The primary non-coherent receiver in the UWB literature is the autocorrelation receiver, which autocorrelates the received signal at specific time lags, circumventing problems of template signal design and multipath energy combining. A unique advantage of the UWB autocorrelation receiver is its robustness to synchronization errors, which has not been explored yet to date. This paper investigates two major UWB schemes employing autocorrelation receivers: the transmitted reference (TR) scheme (R. Hoctor and H. Tomlinson, 2002) and the differential (DF) scheme (M. Ho et al., 2002). Performance is analyzed for TR and DF receivers at different synchronization accuracy levels, their robustness to synchronization errors is shown, and the existence of a tradeoff between performance and synchronization complexity for non-coherent UWB receivers is revealed. As a result of our analysis, comparisons of TR and DF schemes are also made in the presence of synchronization errors, which have not been addressed before. Simulations corroborate our findings. 相似文献