共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
3.
本文探讨了无记忆组合函数的非线性与相关免疫性之间的关系,利用Walsh交换,研究了广义相关免疫函数的频谱特征,并且讨论了Bent函数的广义相关免疫阶数。 相似文献
4.
多值“加法型”组合生成器分析 总被引:1,自引:1,他引:0
文中运用信息论原理对多值“加法型”组合生成器序列进行分析,得到钟控序列与输出序列的互信息为零的结论,证明了钟控输入与输出序列之间互信息是输出序列长度的严格递增函数,进而对控选逻辑序列设计进行分析。 相似文献
5.
给出3个停走生成器在模2加组合方式下符合率的有关结论。此类生成器的输出序列与相应停走生成器的控制序列相互独立;输出序列与相应停走生成器的目标LFSR输出序列不独立,本文对输出序列与目标LFSR序列的符合率进行了讨论,给出有限维联合分布的计算公式。 相似文献
6.
7.
8.
9.
谭俊中 《信息安全与通信保密》2007,(5):158-160
文章描述了代数攻击的一般原理和可攻击的流密码类型,针对带记忆非线性组合流密码的代数攻击,基于Courtios等人的工作,给出了一种新的寻找可用于代数攻击的低阶多元方程的方法。 相似文献
10.
11.
Ma Weiju Feng Dengguo 《电子科学学刊(英文版)》2006,23(6):888-891
I. Introduction BluetoothTM is a standard for wireless short-range connectivity specified by the BluetoothTMspecial interest group in Ref.[1]. The specificationdefines a stream cipher algorithm E0 to be used forpoint-to-point encryption within the Bluetooth net-work. The main component of the Bluetooth streamcipher algorithm is the keystream generator (Blue-tooth combiner) which is derived from the well-known summation generator with four input LinearFeedback Shift Registers (LFSRs). A… 相似文献
12.
Correlation properties of a general binary combiner with memory 总被引:8,自引:0,他引:8
Jovan Dj. Golić 《Journal of Cryptology》1996,9(2):111-126
Correlation properties of a general binary combiner with an arbitrary number M of memory bits are derived and novel design criteria proposed. For any positive integer m, the sum of the squares of the correlation coefficients between all nonzero linear functions of m successive output bits and all linear functions of the corresponding m successive inputs is shown to be dependent upon a particular combiner, unlike the memoryless combiners. The minimum and maximum values of the correlation sum as well as the necessary and sufficient conditions for them to be achieved are determined. It turns out that the security of combiners with memory can be considerably improved if M is not small.An efficient linear sequential circuit approximation (LSCA) method is developed for obtaining output and input linear functions with comparatively large correlation coefficients which is feasible for large M and works for any practical scheme. The method consists in deriving and solving a linear sequential circuit with additional nonbalanced inputs that is based on linear approximations of the output and the component next-state functions. The corresponding correlation attack on combiners with linear feedback shift registers is analyzed and it is shown that every such combiner with or without memory is essentially zero-order correlation immune.A preliminary version of this paper was presented at Eurocrypt '92 and was published in the proceedings. This research was supported in part by the Science Fund of Serbia, Grant #0403, through the Institute of Mathematics, Serbian Academy of Arts and Sciences. 相似文献
13.
平衡H布尔函数的相关免疫性研究 总被引:1,自引:0,他引:1
引入布尔函数的E-导数,并结合导数一起作为工具讨论关系密码系统安全性能的平衡H布尔函数的相关免疫性。通过E-导数和导数深入揭示了平衡H布尔函数0和1值的分布结构,得出判定H布尔函数是否相关免疫的重要结果。并得以采用区分不同结构的计算方法来简化计算,解决了平衡H布尔函数相关免疫最高阶数这一问题。 相似文献
14.
《AEUE-International Journal of Electronics and Communications》2014,68(5):422-428
In this paper, design of a radial power combiner at microwave frequencies has been presented. This structure combines 16 coaxial inputs together and creates one rectangular waveguide output of type WR-187. Although complexity of the proposed combiner compared to combiners with coaxial output has increased, its return loss and VSWR have been improved. In order to achieve a good matching in its high frequency response, a fast tune technique has been applied to design procedure. In its design, a rectangular waveguide has been used together with its radial structure but symmetry among its ports and its phase and amplitude deviations have remained at standard values. Also, in its design, in order to avoid corona breakdown strength of electric field has been controlled and reduced. 相似文献
15.
16.
基于频带分割方法,利用带通(或带阻)滤波器的带外抑制性和三端口环行器的定向传输性,提出了一种新的异频合路器设计方案。该合路器原理通用性强,软件仿真和实物测试结果表明:在排除各器件自身损耗和滤波器带外抑制度小于-30dBc条件下,该合路器能够不失真地同时传输多频具有不同带宽的信号,具有应用于有源相控阵T/R组件中实现同时多功能的潜力。 相似文献
17.
提出了一种平面结构的L波段三路功率合成器,通过两节三路四分之一波长阻抗变换器与平面隔离电阻构成的微带电路实现。合成器使用仿真软件优化计算结果并得到最终设计。测试结果与仿真结果吻合:在1.1GHz至1.7GHz带宽内,各个端口驻波比小于1.13;输入端口间隔离度大于25dB;合成效率大于94.5%且最大幅度不平坦度小于0.05dB。这种功率合成器结构紧凑,性能达到设计要求。 相似文献
18.
19.
实验研究了由三根信号光纤锥形束和一根多模光纤组成的3×1信号耦合器.通过仿真,发现锥形长度越长传输效率和输出光束质量越好,同时也验证了对于低阶模场的吸收要高于高阶模场.实验中,制作了锥区长度为10 mm的3×1信号耦合器,在单纤注入信号功率分别为258 W和365 W的情况下获得转换效率为96.6%的信号输出,总输出功率602W,光束质量为Mx2 = 10.5, My2 = 9.7. 相似文献
20.
文章设计了一种可以使用在固态合成发射机上的三路等分功率波导功分器/合路器。在波导分支定向耦合器的基础上,增加一路副线波导,构成了一个一路输入、一路直通、两路耦合、两路隔离的六端口网络;采用增加波导长度的方式解决了实际应用中的相位补偿问题。另外在功分器的三路输出端增加了微带部分以提高功分器的可调试性。实际测量数据基本符合仿真结果:在1GHz带宽内,功分器的一路插损小于6dB,输入驻波小于1.6;合路器的一路插损小于4.9dB,输出驻波小于1.3。其性能满足使用要求。文章最后对该类型的波导功分器/合路器的设计提出若干改进方案。 相似文献