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The combinatorial construction for a class of optimal optical orthogonal codes

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Science China Mathematics 2002年第10期45卷 1268-1275页

作者：唐煜殷剑兴 Department of Mathematics Suzhou University Suzhou 215006 China

Optical orthogonal code (OOC) has good correlation properties. It has many important appli-cations in a fiber-optic code-division multiple access channel. In this paper, a combinatorial construction foroptimal (15p, 5, 1) optical orthogonal codes with p congruent to 1 modulo 4 and greater than 5 is given byapplying Weil's Theorem. From this, when v is a product of primes congruent to 1 modulo 4 and greater than5, an optimal (15v, 5, 1)-OOC can be obtained by applying a known recursive construction.

关键词： code-division multiple access, optical orthogonal codes, combinatorial construction.

Side-Channel Analysis for the Authentication Protocols of CDMA Cellular Networks

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Journal of Computer Science & Technology 2019年第5期34卷 1079-1095页

作者： Chi Zhang Jun-Rong Liu Da-Wu Gu Wei-Jia Wang Xiang-Jun Lu Zheng Guo Hai-Ning Lu School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China ZhiXun Crypto Testing and Evaluation Technology Co. Ltd.Shanghai 200240China Crypto Group Electrical Engineering DepartmentInstitute of Information and Communication Technologies Catholic University of LouvainLouvain-la-Neuve B-1348Belgium Shanghai Viewsource Information Science and Technology Co. LtdShanghai 200240China

Time-division multiple access (TDMA) and code-division multiple access (CDMA) are two technologies used in digital cellular networks. The authentication protocols of TDMA networks have been proven to be vulnerable to side-channel analysis (SCA), giving rise to a series of powerful SCA-based attacks against unprotected subscriber identity module (SIM) cards. CDMA networks have two authentication protocols, cellular authentication and voice encryption (CAVE) based authentication protocol and authentication and key agreement (AKA) based authentication protocol, which are used in different phases of the networks. However, there has been no SCA attack for these two protocols so far. In this paper, in order to figure out if the authentication protocols of CDMA networks are sufficiently secure against SCA, we investigate the two existing protocols and their cryptographic algorithms. We find the side-channel weaknesses of the two protocols when they are implemented on embedded systems. Based on these weaknesses, we propose specific attack strategies to recover their authentication keys for the two protocols, respectively. We verify our strategies on an 8-bit microcontroller and a real-world SIM card, showing that the authentication keys can be fully recovered within a few minutes with a limited number of power measurements. The successful experiments demonstrate the correctness and the effectiveness of our proposed strategies and prove that the unprotected implementations of the authentication protocols of CDMA networks cannot resist SCA.

关键词： authentication protocol cellular authentication and voice encryption (CAVE) code-division multiple access (CDMA) secure hash algorithm 1 (SHA-1) side-channel analysis

QPSK DS-CDMA System over Rayleigh Channel with a Randomly-Varying Frequency Narrow-Band Interference: Frequency Tracking Analysis

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Wireless Sensor Network 2010年第3期2卷 243-249页

作者： Aloys N. Mvuma 不详

This paper analyses frequency tracking characteristics of a complex-coefficient adaptive infinite-impulse response (IIR) notch filter used for suppression of narrow-band interference (NBI) with a randomly-varying frequency in a quadriphase shift keying (QPSK) modulated direct-sequence code-division multiple-access (DS-CDMA) communication system. The QPSK DS-CDMA signals are transmitted over a frequency non-selective Rayleigh fading channel. The analysis is based on a first-order real-coefficient difference equation with respect to steady-state instantaneous frequency tracking error from which a closed-form expression that relates frequency tracking mean square error (MSE) with number of DS-CDMA active users and NBI power is obtained. Closed-form expressions for optimum notch bandwidth coefficient and step size constant that minimize the frequency tracking MSE are also derived. Computer simulations are included to substantiate the accuracy of the analyses.

关键词： code-division Multiple Access (CDMA) Quadriphase Shift Keying (QPSK) Complex Adaptive IIR Notch Filter Narrow-Band Interference (NBI) Frequency Tracking MSE

The Application of Optical CDMA-Based Fiber Radio Networks in Wireless Sensor Networks

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Wireless Sensor Network 2009年第2期1卷 61-67页

作者： Chao-Chin YANG Department of Electronic Engineering Kun Shan University Tainan Taiwan China

One fiber radio scheme using shifted prime codes for interference elimination is proposed for optical code-division multiple-access (OCDMA) network. By taking advantage of the cyclic property of the shifted prime codes in the same code groups, the proposed compact decoder is low cost and suitable to be used in the task manager node in the applications of wireless sensor networks. The performance comparison for sev-eral OCDMA-based fiber radio networks is also given to clarify the advantage of the proposed one.

关键词： Optical code-division Multiple-Access (OCDMA) Passive Optical Network (PON) Arrayed Waveguide Grating (AWG) Prime code

LOW-COMPLEXITY BLIND MULTIUSER DETECTION OF DS-CDMA SIGNAL IN DISPERSIVE CHANNELS

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Journal of Electronics(China) 2001年第4期18卷 330-336页

作者： Lin Zhiqiang You Xiaohu Wang Yong(National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096) National Mobile Communications Research Laboratory Southeast University Nanjing 210096

The problem of blind multiuser detection in dispersive channels of code-division Multiple-Access (CDMA) in the presence of both Multiple-Access Interference (MAI) and InterSymbol Interference (ISI) is considered. In practice, it is showed that by incorporating the desired user's signature waveform and the auxiliary vector, the information of the user can be identified using the suboptimal subspace method. The major contribution of this paper is to propose a minimum-mean-square-error detector with the suboptimal subspace-based blind technique for joint suppression of MAI and ISI in the dispersive CDMA channels.

关键词： code-division multiple-access Multiuser detection Multiple-access interference Intersymbol interference

ANALYSIS OF SPECTRAL PHASE ENCODING OCDMA SYSTEM WITH PSEUDORANDOM CODING

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Journal of Shanghai Jiaotong university(Science) 2002年第1期7卷 1-3页

作者：张海滨宋文涛黄培中李荣玉 Dept. of Electronic Eng. Shanghai Jiaotong Univ. National Key Lab. on Local Fiber-Optic Communication Networks & Advanced Optical Communication Systems Shanghai 200030 China

Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems with pseudorandom coding. The statistical expectation of multi access interference (MAI) is derived and plotted. The results confirm that MAI can be suppressed effectively by pseudorandom coding with m sequences.

关键词： optical code-division multiple-access (OCDMA) spectral phase encoding m-sequences multiple-access inteference (MAI)

A New Family of Optical codes Based on Complementary Theory for OCDMA System

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Communications and Network 2013年第3期5卷 176-180页

作者： Xing Chen Weixiao Meng School of Electronics and Information Engineering Harbin Institute of Technology Harbin China

A new family of optical codes for Optical code-division Multiple Access (OCDMA) systems, named as Optical Complementary codes (OCCs), is proposed in this paper. The constructions of these codes consist of multiple sub-codes, and the codes have an auto-correlation interference constraint as 0 and a cross-correlation interference constraint as 1. Compared with conventional optical codes such as OPCs, OOCs and 2-D OOCs, the OCC has a shorter code length and higher code efficiency with better correlation property.

关键词： Optical code-division Multiple Access (OCDMA) Complementary code

AN OPTIMIZED SCHEME FOR FAST HANDOFF IN IP-BASED CDMA WIRELESS COMMUNICATION NETWORKS

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Journal of Shanghai Jiaotong university(Science) 2002年第2期7卷 190-193页

作者： DUAN Shi-ping(段世平) XU You-yun(徐友云) SONG Wen-tao(宋文涛) LUO Han-wen(罗汉文) Dept. of Electronic Eng. Shanghai Jiaotong Univ. Shanghai 200030 China Dept. of Electronic Eng. Shanghai Jiaotong Univ. Shanghai 200030 China Dept. of Electronic Eng. Shanghai Jiaotong Univ. Shanghai 200030 China Dept. of Electronic Eng. Shanghai Jiaotong Univ. Shanghai 200030 China

This paper proposed an optimized fast handoff scheme for real time applications in next generation IP based CDMA wireless networks. The idea is to utilize optimized IP multicasting handoff (based on PIM SM), which is triggered by CDMA layer 2 functionality. An IP based cellular network model with WCDMA FDD air interface and IP based packet traffic is adopted. No special network entities and signaling for handoff are added in our network model. The simulation results show that low delay and low packet lost rate can be obtained.

关键词： fast handoff code-division multiple-access (CDMA) IP-based wireless networks