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5th International Workshop on Signal Design and Its Applications in Communications, IWSDA'11

作者： Huang, Bo Fang, Xuming Chen, Yu Provincial Key Lab of Information Coding and Transmission Southwest Jiaotong University Chengdu 610031 China

ISBN: (纸本)9781612840468

In the OFDMA-based cellular relay networks, relay selection and resource allocation are the main problem to be solved. Many present works about resource allocation are for the goal of throughput maximization. In this paper, we propose an adaptive resources allocation algorithm joint relay selection, sub-carrier assignment and power allocation for the goal of energy saving to ensure users' QoS, and the relay scenario is DF, TDD and two-hop single-relay. Simulation results show that the proposed algorithm consumes less energy to transmit the same bits than the greedy energy saving scheme though its spectrum efficiency is worse. © 2011 IEEE.

关键词： Resource allocation

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New sets of low-hit-zone frequency-hopping sequence with optimal maximum periodic partial Hamming correlation

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Science China Chemistry 2015年第12期58卷 158-172页

作者： WANG ChangYuan PENG DaiYuan HAN HongYu ZHOU LiMengNan Provincial Key Lab of Information Coding and Transmission Institute of Mobile CommunicationsSouthwest Jiaotong University

Recently, Chung et al. gave a general method to construct frequency-hopping sequence set(FHS set) with low-hit-zone(LHZ FHS set) by the Cartesian product. In their paper, Theorems 5 and 8 claim that k FHS sets whose maximum periodic Hamming correlation is 0 at the origin result in an LHZ FHS set based on the Cartesian product, and Proposition 4 presented an upper bound of the maximum periodic Hamming correlation of FHSs. However, their statements are imperfect or incorrect. In this paper, we give counterexamples and make corrections to them. Furthermore, based on the Cartesian product, we construct two classes of LHZ FHS sets with optimal maximum periodic partial Hamming correlation property. It is shown that new FHS sets are optimal by the maximum periodic partial Hamming correlation bound of LHZ FHS set.

关键词： frequency-hopping sequence maximum periodic partial Hamming correlation maximum periodicHamming correlation low-hit-zone cartesian product

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An administrable shortcut transmission scheme for OFDMA two-hop relay networks

An administrable shortcut transmission scheme for OFDMA two-...

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Institution of Engineering and Technology International Communication Conference on Wireless Mobile and Computing

作者： Long, Yan Fang, Xuming Zhao, Zhengguang Key Lab. of Information Coding and Transmission Southwest Jiaotong University Chengdu China

ISBN: (纸本)9781849191388

In this paper, an Administrable Shortcut transmission (AST) scheme in two-hop relay networks which enables two Subscriber Stations (SSs) within the same Relay Station (RS) communicate directly via RS's forwarding has been investigated. The scenario of AST scheme in two-hop relay networks and a path selection algorithm based on the minimum slot number with AST scheme are put forward. The simulation results show that the system performance is improved significantly with the increase of the probability of AST scheme taken into account. Therefore, AST scheme could be a potential technology for improving system performance in next generation wireless networks.

关键词： transmissions

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A fair mac scheme for edca based wireless networks

A fair mac scheme for edca based wireless networks

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2009 5th International Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities and Workshops, TridentCom 2009

作者： Rong, He Xuming, Fang Provincial Key Lab of Information Coding and Transmission Southwest Jiaotong University Chengdu 610031 China

ISBN: (纸本)9781424428472

This paper presents a bandwidth occupied time proportion fair MAC algorithm (BOTP-FMAC) for WLAN and Wireless Mesh Network (WMN). It aims to address the unfairness problem in enhanced distributed channel access (EDCA) mechanism, in which higher-priority streaming traffic flows intend to severely deprive the access opportunity of lowerpriority traffic flows due to the capture effect, especially when the network load is near saturation. By dynamically tuning the parameters of channel contention and the threshold of bandwidth occupied time proportion for priority queue adaptively, BOTPFMAC algorithm can achieve a weighted fair allocation of the bandwidth resource among different traffic flows. The simulation results indicate that our proposed algorithm substantially improves the fairness and attains a greater aggregate throughput. Additionally, it is easy to carry out without generating network overhead.

关键词： Medium access control

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Performance analysis of frequency-hopping multiple-access communications with OFDM-BPSK scheme

Performance analysis of frequency-hopping multiple-access co...

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3rd International Conference on Communications and Networking in China, ChinaCom 2008

作者： Zeng, Qi Peng, Daiyuan Liang, Hongbin Provincial Key Lab. of Information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu Sichuan 610031 China

ISBN: (纸本)9781424423736

In this paper, a novel communication system is introduced, i.e., the frequency-hopping multiple-access OFDM-BPSK communication system. Based on characteristic function method, the bit error rate (BER) performance of the system is derived in additive white Gaussian noise (AWGN) and Rayleigh fading channels. The numerical results firstly indicate the relationship between BER and the parameters such as the size of frequency slots set Nh, the number of OFDM subcarriers N and the number of users Nu. By the numerical and simulation results, the frequency resource of OFDM-BPSK-FHMA system is saved and the BER is decreased under the same parameter compared with other similar communication systems.

关键词： Bit error rate

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POWER ALLOCATION OF DATA DEPENDENT SUPERIMPOSED TRAINING

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Journal of Electronics(China) 2008年第5期25卷 595-600页

作者： Wang Ping Yuan Weina Fan Pingzhi Provincial Key Lab of Information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu 610031 China

Data Dependent Superimposed Training(DDST) scheme outperforms the traditional su-perimposed training by fully canceling the effects of unknown data in channel *** DDST,however,the channel estimation accuracy and the data detection or channel equalization performance are affected significantly by the amount of power allocated to data and superimposed training sequence,which is the motivation of this *** general,for DDST,there is a tradeoff between the channel estimation accuracy and the data detection reliability,i.e.,the more accurate the channel estimation,the more reliable the data detection;on the other hand,the more accurate the channel estimation,the more demanding on the power consumption of training sequence,which in turn leads to the less reliable data *** this paper,the relationship between the Signal-to-Noise Ratio(SNR) of the data detector and the training sequence power is *** optimal power allocation of the training sequence is derived based on the criterion of maximizing SNR of the *** and simulation results show that for a fixed transmit power,the SNR and the Symbol Error Rate(SER) of detector vary nonlinearly with the increasing of training sequence power,and there exists an optimal power ratio,which accords with the derived optimal power ratio,among the data and training sequence.

关键词： Superimposed training Power allocation Channel estimation

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New quaternary sequences of even length with optimal auto-correlation

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Science China(information Sciences) 2018年第2期61卷 125-137页

作者： Wei SU Yang YANG Zhengchun ZHOU Xiaohu TANG School of Economics and Information Engineering Southwestern University of Finance and Economics Science and Technology on Communication Security Laboratory School of Mathematics Southwest Jiaotong University Provincial Key Lab of Information Coding and Transmission Institute of Mobile CommunicationsSouthwest Jiaotong University

Sequences with low auto-correlation property have been applied in code-division multiple access communication systems, radar and cryptography. Using the inverse Gray mapping, a quaternary sequence of even length N can be obtained from two binary sequences of the same length, which are called component sequences. In this paper, using interleaving method, we present several classes of component sequences from twin-prime sequences pairs or GMW sequences pairs given by Tang and Ding in 2010; or two, three or four binary sequences defined by cyclotomic classes of order 4. Hence we can obtain new classes of quaternary sequences, which are different from known ones, since known component sequences are constructed from a pair of binary sequences with optimal auto-correlation or Sidel'nikov sequences.

关键词： binary sequences quaternary sequences Gray mapping interleaving cyclotomy

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Performance of Turbo coded wireless link for SISO-OFDM, SIMO-OFDM, MISO-OFDM and MIMO-OFDM system

Performance of Turbo coded wireless link for SISO-OFDM, SIMO...

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14th International Conference on Computer and information Technology, ICCIT 2011

作者： Kamruzzaman, M.M. Key Lab. of Information Coding and Transmission Southwest Jiatong University Chengdu Sichuan China

ISBN: (纸本)9781612849065

In this paper, performance of a Turbo coded OFDM wireless link is evaluated in the presence of Rayleigh fading for SISO, SIMO, MISO and MIMO system. Data are encoded using turbo encoder then modulated by QPSK or 16 QAM or 64 QAM and further encoded using STBC, and the encoded data are split into n streams which are modulated by OFDM and simultaneously transmitted using n transmit antennas. It is observed that the turbo coded SISO-OFDM system provides 21 dB coding gain at 10-4, turbo coded SIMO-OFDM system provides 20 and 13 db coding gain for 2 and 4 receive antennas respectively at a BER of 10-6, turbo coded MISO-OFDM system provides 17 and 12 dB coding gain for 2 and 4 transmit antennas respectively at a BER of 10-6 and turbo coded MIMO-OFDM system provides 11 to 13 dB coding gain for different combination of transmit and receive antennas at BER 10-6 compare to uncoded SISO-OFDM, SIMO-OFDM, MISO-OFDM and MIMO-OFDM system. © 2011 IEEE.

关键词： Orthogonal frequency division multiplexing

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A relative risk model for anomaly detection in wireless sensor networks

A relative risk model for anomaly detection in wireless sens...

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2008 International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2008

作者： Jiayu, Tang Pingzhi, Fan Key Lab. of Information Coding and Transmission IMC Southwest Jiaotong University Chengdu China

ISBN: (纸本)9781424421084

Localization anomaly detection (LAD) for a wireless sensor network (WSN) plays a prominent role in defending against attacks on localization services. However, it is a difficult task to evaluate the effectiveness of the anomaly detection scheme according to complexity and uncertainty in various applications. This paper presents a relative risk model approach that was proposed for ecological risk assessment (ERA) to tackle this problem. The problem formulation and model-building process is described in detail. Our numerical simulation demonstrates that this relative risk model method is quite effective to the quantitative assessment of vulnerability analysis in wireless sensor networks. © 2008 IEEE.

关键词： Wireless sensor networks

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New p-ary sequences with low correlation and large family size

New p-ary sequences with low correlation and large family si...

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作者： Liu, Fang Peng, Daiyuan Tang, Xiaohu Niu, Xianhua Provincial Key Lab of Information Coding and Transmission School of Information Science and Technology Southwest Jiaotong University Chengdu China

For an odd prime p, two new families of p-ary sequences of period p n - 1 are constructed for odd n = 2l + 1 = (2m + 1)e and even n = 2l = 2me, respectively. It is shown that, for a given integer ρ with 1 ≤ ρ ρ m, the proposed sequence families both have maximum correlation magnitude 1 + pn+2(ρ-1)e+2/2 , family size (pn - 1)p( ρ-1)n + 1, and maximum linear span n(n+3)/2. Copyright © 2010.

关键词： Code division multiple access

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