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De-noising with Novel DWT-MFCC for Speaker Recognition

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通讯和计算机（中英文版） 2006年第7期3卷 54-57页

作者： Zhengquan Qiu Junxun Yin School of Electronic and lnformation engineering South China University of Technology Guangzhou 510640. China

In this paper, three modifications for speaker recognition are presented. First, for threshold in the wavelet domain, a semi-soft threshold function that shows advantages over hard and soft threshold function with respect to variance and bias of the estimated value is used. Second, in the classical cepstrum calculation, a log transformation is used to modify the power spectrum. Generally this transformation is done after the filter-bank. This paper shows that performing this transformation before the filter bank is more interesting in the experiment. The experiment shows that the proposed method has more advantages for speaker recognition in noise circumstance than the speaker recognition with simple MFCC (Mel-scale Frequency Cepstral Coefficients). Third, in order to improve recognition performance and training velocity, modified OGMM is applied in recognition stage. The proposed method has very good guidance for real-time speaker recognition.

关键词：计算机软件数据库系统计算机技术软件开发

Bilayer expurgated LDPC codes with uncoded relaying

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Digital communications and Networks 2017年第3期3卷 176-179页

作者： Md. Noor-A-Rahim Nan Zhang Sk. Md. Rabiul Islam Y.L. Guan Centre for Infocomm Technology (INFINITUS) Nanyang Technological University Singapore Institute for TelecommunicationsResearch University of South Australia Adelaide Australia dept.of Eleetronics and communication engineering Khulna University of Engineering & Technology Bangladesh

Bilayer low-density parity-check （LDPC） codes are an effective coding technique for decode-and-forward relaying, where the relay forwards extra parity bits to help the destination to decode the source bits correctly. In the existing bilayer coding scheme, these parity bits are protected by an error correcting code and assumed reliably available at the receiver. We propose an uneoded relaying scheme, where the extra parity bits are forwarded to the destination without any protection. Through density evolution analysis and simulation results, we show that our proposed scheme achieves better performance in terms of bit erasure probability than the existing relaying scheme. In addition, our proposed scheme results in lower complexity at the relay.

关键词： Bilayer codes LDPC codes Density evolution Decode-and-forward relaying

Proposal for a cross layer scheme for real-time wireless video

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2006年第10期7卷 1690-1694页

作者： JEYARAJ Arulsaravana CHENG Liang EL ZARKI Magda EECS Department the Henry Samueli School of Engineering University of California Irvine CA-92697 USA NVIDIA Corporation Santa Clara California CA-95050 USA CS Department DonaM Bren School of lnformation ＆ Computer Sciences University of California Irvine CA-92697 USA

This paper focuses on the design of the cross layer between the video application layer and the MIMO physical layer. MIMO physical layer research has promised an enormous increase in the capacity of wireless communication systems. Also MIMO wireless systems operate under fading conditions where the channel faces arbitrary fluctuations. Since the wireless channel changes over each coherence period, the capacity of the wireless channel, given the power constraints, changes. Hence to make efficient use of the available capacity one needs to adapt the video bit rate. However it is impossible to adapt at the application layer as changing the parameters of the video takes more time than the coherence period of the channel. In this paper we address this problem through a novel solution and also investigate its performance through a simulation study.

关键词： MIMO V-BLAST Adaptive modulation Diversity Constant bit rate (CBR) Cross layer design Power control Fine granular scalability (FGS)

Capacity and Flexibility Improvement of Traffic Aggregation for Fixed 5G:Key Enabling Technologies,Challenges and Trends

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China communications 2022年第12期19卷 1-13页

作者： Jing Zhang Tianhai Chang Zhuqiang Zhong Xianqing Jin Shaohua Hu Taowei Jin Jiahao Zhou Mingyue Zhu Yi Yu Jianming Tang Liangchuan Li Kun Qiu School of communication and Information engineering University of Electronic Science and Technology of ChinaChengduSichuan 611731China Optical Research dept Huawei Technologies518129ShenzhenChina School of Electronic engineering Bangor UniversityBangorLL571UTUK

As the emergence of various highbandwidth services and the requirements to support 5G/Wi-Fi 6 wireless networks,the next generation fixed networks,i.e.F5G,are expected to be realized in the 5G era.F5G is endowed with new characteristics,including ultra-high bandwidth,all-optical connections and optimal service *** the prospect of optical-to-everywhere,optical technologies are used for mobile front-haul,mid-haul,and *** access networks would play an important role in F5G to support radio access network and fixed access ***-latency PON is a key for cost effective-haul traffic *** terms of signal transmission,intensity modulation directdetection(IM-DD)is a promising scheme due to its simple *** fundamental challenge associated with direct-detection is the disappearance of the transmitted signal’s *** access network,the flexibility and low latency are the two key factors affecting service *** this article,we review the evolution of PONs and the challenges of current PONs in *** analyze key enabling digital signal processing(DSP)techniques,including detection linearization for direct-detection and simplified coherent detection,adaptive equalizers,digital filer enabled flexible access network and low-latency inter-ONU ***,we discuss the developing trends of future optical access networks.

关键词： optical fiber communication flexible access network optical field recovery inter-ONU communication

Energy Scheduling with Roles Dormant Cells （SRDC） in wireless sensor network （WSN）

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Journal of Energy and Power engineering 2009年第12期2卷 46-52页

作者： Maan Younis Abdullah GUI Wei-hua Naf Alsharabi School of lnformation Science and engineering Central South University Changsha 410083 China Faculty of engineering Sana＇a University Sana＇a Yemen

Power consumption is the main challenge to expand the wireless sensor network, since the active nodes are vulnerable to energy consumption. This paper proposes the tasks scheduling and distribution energy management mechanism of roles dormant cells to curb excessive consumption of energy in the performance of duplicated tasks. Experimental results verify the proposal existing low energy adaptive clustering hierarchy （LEACH） protocol with SRDC approach establishes a low-energy communication structure and increases the lifetime.

关键词： Energy Management SRDC LEACH WSN

Distributed power control algorithm based on game theory for wireless sensor networks

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Journal of Systems engineering and Electronics 2007年第3期18卷 622-627页

作者： Na Chengliang Lu Dongxin Zhou Tingxian Li Lihong dept. of Electronic and communication engineering Harbin Inst. of Technology Harbin 150001 P. R. China ZTE-S_NCEPU Union Lab Nanchang 330058 P. R. China

Energy saving is the most important issue in research and development for wireless sensor networks. A power control mechanism can reduce the power consumption of the whole network. Because the character of wireless sensor networks is restrictive energy, this paper proposes a distributed power control algorithm based on game theory for wireless sensor networks which objects of which are reducing power consumption and decreasing overhead and increasing network lifetime. The game theory and OPNET simulation shows that the power control algorithm converges to a Nash Equilibrium when decisions are updated according to a better response dynamic.

关键词： wireless sensor networks power control game theory convergence

A Two-Step Authentication Framework in Mobile Ad-Hoc Networks

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China communications 2007年第1期4卷 28-39页

作者： Nikos Komninos Dimitris Vergados Christos Douligeris Algorithms & Security Group Athens Information Technology19002 Peania Greece dept.of Information and communication Systems engineering University of the Aegean83200 Samos Greece dept.of Informatics University of Piraeus18534 Piraeus Greece

The lack of fixed infrastructure in ad hoc networks causes nodes to rely more heavily on peer nodes for ***,establishing trust in such a distributed environment is very difficult, since it is not straightforward for a node to determine if its peer nodes can be *** additional concern in such an environment is with whether a peer node is merely relaying a message or if it is the originator of the *** this paper,we propose an authentication approach for protecting nodes in mobile ad hoc *** security requirements for protecting data link and network layers are identified and the design criteria for creating secure ad hoc networks using several authentication protocols are *** based on zero knowledge and challenge response techniques are presented and their performance is evaluated through analysis and simulation.

关键词： authentication steps link and network layers ad hoc networks

Study on pattern time delay shift coding scheme

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Journal of Marine Science and Application 2006年第3期5卷 51-56页

作者： YIN Jing-wei HUI Jun-ying WANG Yi-lin YAO Zhi-xiang College of Underwater Acoustic Eng. Harbin Engineering University Harbin 150001 China College of lnformation ＆ Electric Navy Engineering University Wuhan 430043 China

Pattern Time Delay Shift Coding (PDS) scheme is robust for underwater acoustic communication. The digital information are encoded in the time delay shift values of the Pattern, so the PDS scheme belongs to the Pulse Position Modulation (PPM). Several Patterns are selected for code division that the communication system could have a high ability to mitigate the inter-symbol interference (ISI) caused by multipath channel. Four communication channels work on the same time divided by different frequency, which lead to 1000bits/s of the data rate of communication. The simulation experiments show that the PDS system could adapt to many underwater acoustic channels for high data rate and high reliability.

关键词： pattern time delay shift coding underwater acoustic communication inter-symbol interference (ISI)

MULTI-RESOLUTION LEAST SQUARES SUPPORT VECTOR MACHINES

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Journal of Electronics(China) 2007年第5期24卷 701-704页

作者： Wang Liejun Zhang Taiyi Zhou Yatong dept of Information and communication Eng. Xi＇an Jiaotong University Xi＇an 710049 China dept of Information Science and engineering Xinjiang University Urumchi 830046 China

The Least Squares Support Vector Machines (LS-SVM) is an improvement to the SVM. Combined the LS-SVM with the Multi-Resolution Analysis (MRA),this letter proposes the Multi-resolution LS-SVM (MLS-SVM).The proposed algorithm has the same theoretical framework as MRA but with better approximation *** a fixed scale MLS-SVM is a classical LS-SVM,but MLS-SVM can gradually approximate the target function at different *** experiments,the MLS-SVM is used for nonlinear system identification,and achieves better identification accuracy.

关键词： Support Vector Machines (SVM) Least square method Multi-Resolution Analysis (MRA) Nonlinear system identification