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2004 Vol. 26, No. 1

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Articles
A Sparse Multifiber and Wavelength Assignment Algorithm in WDM-Networks
Xiang Bing, Wang Sheng, Li Le-min
2004, 26(1): 1-6.
Abstract:
Constrained by the price and technology, not only the wavelength converters laid in WDM network but also the Wavelength Per Fiber (WPF) is limited. But there are usually some spare fibers in links, so it is important to make full use of these fibers ...
Hierarchical Key Management in Secure Multicast
Zhu Wen-tao, Xiong Ji-ping, Li Jin-sheng, Hong Pci-lin
2004, 26(1): 7-13.
Abstract:
Multicast is a preferred communication technique in multiple recipients and its importance is rapidly growing. The Internet Group Management: Protocol(IGMP) does not provide access control of the members. To provide communication confidentiality, tra...
The Network Managenent Service Access Model and Its Implementation
Zhan Zhi-qiang, Qiu Xue-song, Meng Luo-ming
2004, 26(1): 14-19.
Abstract:
The characteristics of the network management service access in the Telecommunication Management Network (TMN) arc analyzed. According to these characteristics, the Network Management Service Access Model(NMSAM) applying extensible Markup Lan-guage(X...
A Novel Dynamic Sequential Allocation Algorithm of OVSF Codes
Zhu Chun-mei, Wu Wei-ling
2004, 26(1): 20-26.
Abstract:
This paper analyzes the feature of W-CDMA downlink OVSF code. A novel dynamic sequential allocation algorithm is presented according to code blocking ratio in the stochastic allocation. Low level codes are allocated firstly, and codes in the same lev...
Performance Analysis of Coherent Delay-Locked Loop Based on Interpolation and Integrate/Dump Filter
Li Ke-xiang, Song Guo-wen
2004, 26(1): 27-34.
Abstract:
A Coherent Delay-Locked Loop(CDLL) is proposed based on interpolation and integrate/dump filter for PN code tracking in DS-CDMA systems. The performance of the CDLL is investigated under AWGN and multi-user environments, and closed-form expres-sions ...
A New Distributed Power Control Algorithm
Xiao Kun, Wu Shi-qi
2004, 26(1): 35-40.
Abstract:
This paper first proposes the prototype algorithm of an improved distributed power control (IDPC). In this algorithm, mobile units adjust their transmitter powers ac-cording to not only their power levels at last iterative step but also the largest a...
A Cooperative Location Method Based on Chan and Taylor Algorithms
Liu Lin, Deng Ping, Fan Ping-zhi
2004, 26(1): 41-46.
Abstract:
In this paper, two location algorithms, i.e. Chan and Taylor series expansion methods, are analyzed and a cooperative location method based on Chan and Taylor algorithms is proposed. The performance of the cooperative location method is simulated und...
A Transmit Diversity Technique for OFDM
Xiao Jian-hua, Zhang Ping
2004, 26(1): 47-52.
Abstract:
A simple transmit diversity technique assumes that channel does not change over two symbol period of time. Therefore, this technique is not suitable for time varying channels. This paper modifies the transmit diversity technique to accommodate time v...
Time Delay Estimation by Using Modified Crosspower Spectrum Phase Technique
Ma Xiao-hong, Lu Xiao-yan, Yin Fu-liang
2004, 26(1): 53-59.
Abstract:
The Crosspower Spectrum Phase (CSP) technique is a well known time delay estimation method. A relatively precise time delay estimation can be achieved by using it in the environment of weak noise and medium reverberation. The performance degrades sha...
The Signal Structure Analysis of Non-Gaussian Noise Based on Wavelet Packet Transform
Xiang Qian, Lin Chun-sheng, Gong Shen-guang
2004, 26(1): 60-64.
Abstract:
By exploiting wavelet packet transform to analyze signals both in time and frequency space, this paper researches the statistic property of non-Gaussian stationary noise and its signal structure. The results of classic optimum detector arc extended t...
The Inverse Square Attack of Rijndael Cipher
Duo Lei, Li Chao
2004, 26(1): 65-71.
Abstract:
Rijndael was selected as the AES. The best-known attack against Rijndael is still the one presented by the designers called Square attack. Square attack is a chosen plaintext attack. In this paper a new kind of attack called Inverse Square attack is ...
Composite Attack on Sequence Cipher
Sun Lin-hong, Ye Ding-feng, Lǚ Shu-wang, Feng Deng-guo
2004, 26(1): 72-76.
Abstract:
The composite attack on sequence cipher is developed and forward feedback network is analyzed by the composition of correlation attack and inversion attack, both theory and experimental results show its complexity. Finally, comparison with normal att...
Space-Time Adaptive Processor Rank-Reduced by Multistage Nested Wiener Filter
Sun Xiao-chang, Huang fu Kan, Yuan Jun-quan, Wang Zhan
2004, 26(1): 77-81.
Abstract:
An anti-jamming space-time adaptive processor rank-reduced by Multistage Nested Winner Filter(MSNWF) is presented in this paper. Such processor can overcome the need of freedom degrees in traditional array processing while maintains the computa-tiona...
Weighted Myriad Filter Implementation with Genetic Algorithm in -Stable Noise Environments
Yang Jun, Ma Xiao-yan, Wan Shan-hu
2004, 26(1): 82-88.
Abstract:
A novel algorithm is proposed based on the genetic theory, which has global optimum searching characteristic. Meanwhile, considering its computational cost, decimal code, not binary one is used in operation of the operators. Moreover, a modified adap...
Locating Calibrators in Airborne InSAR Calibration
Wang Yan-ping, Peng Hai-liang, Yun Ri-sheng
2004, 26(1): 89-94.
Abstract:
The condition number of sensitivity matrix is a key factor that influences the performance of InSAR calibration. On the basis of InSAR calibration theory, basic principles of locating calibrators are proposed, and constraints of locating calibrators ...
Study on the Azimuth Resolution of Spaceborne SAR Working on Spotlight Mode
Gao Xiang-wu, Tian Xu-wen, Yang Ru-liang
2004, 26(1): 95-99.
Abstract:
From the difference of imaging geometry between spaceborne SAR, and airborne SAR, traditional formula computing the azimuth resolution of airborne SAR working on spotlight mode will bring big errors if it is used for spaceborne SAR. In this paper, th...
Influence of the Frequency Instability on the Bistatic-SAR Imaging
Tang Zi-yue, Zhang Shou-rong
2004, 26(1): 100-106.
Abstract:
The high stability of frequency sources is the foundation to the phase synchronization of the Bistatic Synthetic Aperture Radar (BiSAR) system. This paper analyzcs the influence of various frequence instabilities of sources in transmitter and receive...
Radar Doppler Properties Evaluation in Elliptic Orbits
Wang Rui, Yang Ru-liang
2004, 26(1): 107-111.
Abstract:
For spaceborne Synthetic Aperture Radar (SAR), Dopplcr property is one of the most important factors for azimuth performance. In this paper, the elliptic orbit is applied. The Doppler centroid frequency and Doppler frequency rate are evaluated in dif...
Design of a Small Broadband Array System for High-Frequency Surface Wave Radar
Gao Huo-tao, Yang Zi-jie, Li Jie, Wei Zhong-wei
2004, 26(1): 112-117.
Abstract:
According to the requirements of engineering design for High-Frequency Surface Wave Radar (HF-SWR), at first, a small broadband transmitting antenna is optimized based on the theory of log periodic antennas. Then, based on the end-fire array theory, ...
Research on Dielectric Layer PBG Structures in Waveguide Based on FDTD
Yan Dun-bao, Yuan Nai-chang, Fu Yun-qi
2004, 26(1): 118-123.
Abstract:
In this paper, a new dielectric layer PBG structures in waveguide is introduced, and numerical analysis to its stop-band characteristic is finished. The design of PBG structures and the effect of the size of period, the number of periods, the size of...
Partial Scan Design Based on Circuit State Information and Conflict Analysis
Xiang Dong, Liu Xin, Xu Yi
2004, 26(1): 124-130.
Abstract:
A multiple phase partial scan design method that breaks critical cycles using a combination of valid circuit state information and conflict analysis is proposed. It is quite cost-effective to obtain circuit state information via logic simulation, the...
A Kind of Priority-Based Self-Adapting I/O Scheduling Scheme for Integrated-Service Access System
Han Guo-dong, Zhang Xing-ming, Deug Yong, Wu Jiang-xing
2004, 26(1): 131-136.
Abstract:
On the basis of the introduction of the integrated-service access system, this paper introduces a new kind of scheduling scheme called priority-based parameter self-adapting round-robin I/O scheduling, and the implementation of this scheme in integra...
Study of Chaotic Spread-Spectrum Sequences Based on Neural Networks
Liu Lian-hui, Shi Jun, Li Bai-ping, Wang Jian-xin
2004, 26(1): 137-141.
Abstract:
The chaos generation neural network based on the excellent learning ability and synaptic weight database are built to generate many chaotic spread-spectrum sequences trained by the modified back-propagation algorithm with various discrete chaotic tim...
Controlling Chaos in a Neural Network Based on the Orbit Space Compression
He Guo-guang, Cao Zhi-tong, Chen Hong-ping, Zhu Ping
2004, 26(1): 142-145.
Abstract:
In this paper, a controlling chaos method of the orbit space compression is proposed for a Chaotic Neural Network(CNN). The computer simulation of the chaotic behaviors of the CNN proves that each pattern can be controlled using the orbit space compr...
A Robust Adaptive Beamformer
Guo Qing-hua, Liao Gui-sheng
2004, 26(1): 146-150.
Abstract:
The linearly constrained adaptive beamformer is hypersensitive to the amplitude and phase errors of antenna array when the signal-to-noise ratio exceeds a certain threshold. Even if the array imperfections are slight, the beamformer suppresses the de...
Fast HRP Algorithm Realization Methods Based on the Wavelet Multiresolution Decomposition
Liu Dong, Xiang Jing-lin
2004, 26(1): 151-156.
Abstract:
The Matching Pursuit(MP) algorithms display good performance of recurring the orthonormal sparse structure of signals, but the signal decomposition process widely ex-hibits pre-echo artifact and local mismatch, so HRP algorithm was proposed by S. Jag...
The Influence of the Rotating of the Cluster Micro-Satellite on Height Measurement of InSAR
Zhang Xiao-ling, Zeng Bin, Huang Shun-ji
2004, 26(1): 157-162.
Abstract:
The cluster micro-satellite Synthetic Aperture Radar(SAR) system is an inno-vative SAR system brought forward recently. In the cluster micro-satellite system, tech-nology of cross-track interferometic SAR imaging processing is studied. The influence ...
Info from EIS of NSFS
2004, 26(1): 163-164.
Abstract:
2004, 26(1): 165-168.
Abstract: