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Journal of Beijing University of Posts and Telecommunications

  • EI核心期刊

Current Issue

  • Papers

    • Energy Adaptive Flooding Broadcast Strategy for Ad hoc Network
    • MIAO Jian-song, DING Wei, SUN Dan-dan
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 1-4. DOI:10.13190/jbupt.2007s1.1.miaojs
    • Abstract ( 2446 )     HTML       
    • In order to avoid Broadcast Storm, the Energy Adaptive flooding Broadcast (EAB) strategy is proposed. The algorithm is based on probability rebroadcast to reduce the number of rebroadcast. According the remain energy of the nodes,EAB decides which nodes need to rebroadcast to reduce the chance of contention and collision among neighboring nodes in the networks and restrain the flooding effectively. Analyses and simulations show that adaptive flooding broadcast strategy outperforms the ordinary flooding broadcast method and increases the reach ability in the Ad hoc networks.
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    • A New Improved AODV Protocol For Node Disjoint Multipath Routing
    • ZHU Ying, WEI Rong, WEI Yu-xin, WU Mu-qing
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 5-9. DOI:10.13190/jbupt.2007s1.5.zhuy
    • Abstract ( 1854 )     HTML       
    • This paper proposes a improved multipath routing protocol—TRND-AODV(Tree Root Node Disjoint Ad-Hoc On Demand distance Vector),which is based on AODV. By Node Tree Root algorithm, it can realize node disjoint multipath routing efficiently and rapidly. The paper also analyses the routing stability、the optimized number of multipath、network load and traffic in theory. Simulation results show that TRND-AODV is better than AODV in ways of average lower end to end delay、route discovery frequency and network throughout.
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    • Early Detection of All-Zero DCT Coefficients Block Based on DCT Coefficients Distribution Model
    • XIE Zheng-guang, LIU Yong, LIU Wen-jun, YANG Tie-jun
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 10-13. DOI:10.13190/jbupt.2007s1.10.xiezhg
    • Abstract ( 2136 )     HTML       
    • In video coding, the value of residual block produced by inter prediction is usually small. When the residual block is transformed and quantized, the discrete cosine transform (DCT) coefficients quantized are all zero, especially in low bit-rate video applications. The early detection technique proposed is to reduce the encoding computation complexity. If these residual blocks are pre-determined, and then they are not required to be DCT transformed and quantized. This is the so-called early detection method of all-zero DCT coefficients block (AZB). Based on analysis of the false-judgment and miss-judgment of the existing algorithms, the analysis of DCT coefficients distribution, characteristics of the integer DCT (IntDCT) and quantization, an innovative algorithm for early detection AZB is proposed. The experimental results show that the proposed algorithms improve the judge efficiency up to 35% higher than that of existing methodologies.
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    • The Economic Effect Research of Two Network Structure on the IPTV
    • WANG Qi, CAO Yuan-zhi, LV Ting-jie
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 18-21. DOI:10.13190/jbupt.2007s1.18.wangq
    • Abstract ( 2060 )     HTML       
    • The paper compares the P2P network model with the Client/ Server network model from economy. Through the comparison on an approximate cost model, we find that even with large revenue sharing factor (i.e., peers get a larger portion of the per-customer than the provider), the P2P network model still achieves a higher profit with a reasonable number of customers. And the result of the comparison demonstrates the cost-effectiveness of the P2P network model, since it requires a small initial investment in the infrastructure. So these show that the economic potential of a large-scale media streaming service built on top of a P2P infrastructure. The provider can manage the level of cooperation offered by peers.
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    • Analysis of Ellipse Zone Routing Protocol based on Location-Triggered
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 22-26. DOI:10.13190/jbupt.2007s1.22.mamh
    • Abstract ( 1803 )     HTML       
    • Propose the ellipse zone routing protocol which touched off in position and made full use of geographical position information in order to reduce the controlling message expenses and route expenses effectively, and on the other hand, it can improve the global performance of the network. Through mathematics analysing and comparing between the routing protocol touched off in the position and that touched off regularly , we get the idea that the former can reduce the controlling expenses greatly. The paper utilizes the oval regional route characteristic mathematics model to analyze, and provides the corresponding expense function. There are very good advantages on performance effectively of the oval directional inundation mechanism of area, such as preventing the inundation cavity avoiding and the protocol can be realized simply and conveniently. The simulation in the paper has verified the result.
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    • Intrusion Detection Technology Based on KFDA-SVM
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 27-31. DOI:10.13190/jbupt.2007s1.27.weiyx
    • Abstract ( 2420 )     HTML       
    • In order to improve the detection rate and reduce the training time, KFDA-SVM intrusion detection technology is proposed which combines the feature extraction technology and classification algorithm. In the proposed algorithm, the KFDA is used to extract the optimal discriminant vectors and then the SVM is adopted to classify the projected data. A mixture of kernels based HVDM is proposed according to the high dimensional and heterogeneous datasets acquired in the intrusion detection. Results of the experiment using KDD 99 indicate the effectiveness of the algorithm.
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    • WiMAX Base Station Site Placement Based on Improved Genetic Algorithm
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 37-41. DOI:10.13190/jbupt.2007s1.37.lium
    • Abstract ( 2026 )     HTML       
    • In order to efficiently and accurately decide the sites of base station of WiMAX networks, a problem model for it was founded, and the application of an improved generation algorithm (GA) on base station site placement was researched. The selection operator, the crossover operator, the mutation operator and the transfer operator of GA were improved, and an effective crisscross searching operator was designed. Simulation results show that contrasting to existent algorithms, the improved GA greatly accelerates the convergence rate, and obtains approximate best solutions of the problem.
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    • DOA Estimation algorithm used in Ad-Hoc Network Terminals
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 42-47. DOI:10.13190/jbupt.2007s1.42.guol
    • Abstract ( 1573 )     HTML       
    • A Direction of Arrival (DOA) estimation algorithm is presented based on the eight unit circular array. It can cover plane excellently. The orthogonal channel code is used. It approaches the DOA of the desired signal iteratively through the hardware variable phase shifter. The algorithm implementation, pilot encoding and the pilot placement are discussed. The merits of its accuracy and quick convergence make it suitable to be used in Ad-Hoc network terminals. Simulation results verify the algorithm.

    • Supplementary Material | Related Articles
    • 3-D Impedance Method and Parallel Implementation
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 57-60. DOI:10.13190/jbupt.2007s1.57.124
    • Abstract ( 1760 )     HTML       
    • We have extended the previously three-dimensional impedance method to parallel implementation for bioelectromagnetic applications. Based on Maxwell’s equation, we deduced the 3-D IM and found the association between the minimum incident wave length and the resolution of human body model. Furthermore, we designed a communication scheme to exchange the border data for processors during iteration by Message Passing Interface (MPI) library and a parallel system was set up. We present the solution of the induced current caused by exposure to power line in visible human body model whose resolution is 3 mm and contend 196×114×626 cells. The results had confirm the validation and effective of parallel IM.
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    • Improved Trellis-coded Modulation Concatenated with Space-Time Block Coding
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 61-64. DOI:10.13190/jbupt.2007s1.61.125
    • Abstract ( 1987 )     HTML       
    • The scheme of asymmetric trellis-coded modulation concatenated with space-time block coding was proposed. The trellis graph was designed and the optimal constellation rotating angle was presented which based on the rule of maximize the minimum product-sum distance. Simulation results show that the proposed ATCM-STBC scheme outperforms TCM-STBC with no extra power and bandwidth efficiency whether under quasi-static fading channels or fast Rayleigh fading channels.
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    • Partition-based Resource Reservation and Routing Strategy for OBS network
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 65-69. DOI:10.13190/jbupt.2007s1.65.zhengw
    • Abstract ( 1981 )     HTML       
    • A novel strategy for OBS network called Partition-based Resource Reservation and Routing Strategy is proposed. The proposed strategy partitions the OBS core network into multiple regions, and different resource reservation and routing protocols are performed in intra-region and inter-region. The proposed strategy takes the advantages of two different routing schemes. Simulations show that the proposed strategy has improved the overall network throughput and reduced the average blocking probability thus reduces the retransmission delay. The node processing time of the proposed strategy is lower than hop by hop routing scheme and the burst block probability is lower than fixes path routing scheme.
    • Supplementary Material | Related Articles

    Reports

    Papers

    • Real-time Fair Scheduling Algorithm for Downlink OFDM Systems
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 75-79. DOI:10.13190/jbupt.2007s1.75.zhangtk
    • Abstract ( 2450 )     HTML       
    • A downlink resource scheduling scheme called real-time fair scheduling algorithm is proposed for cellular mobile telecommunication system which is based on orthogonal frequency division multiplexing technology. This algorithm achieves a relatively fair subchannel assigning scheme by a novel initialization for subchannel assignment, and then employs fairness precision parameters to control iterative loop for further optimization to make the subchannel assignment fairer, furthermore, this algorithm uses a minimal fairness index to make the assignment scheme fulfill the fairness restriction. Simulation analysis has proved that real-time fair scheduling algorithm could ensure all the users share the bandwidth resource fairly and fulfill predefine minimal fairness index in every scheduling interval.
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    Reports

    • BitTorrent Traffic Feature Analysis and Model
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 84-87. DOI:10.13190/jbupt.2007s1.84.liuf
    • Abstract ( 1844 )     HTML       
    • The traffic of operator network was analyzed, feature of BitTorrent traffic was obtained, an approach to model traffic in the perspective of periodic traffic feature was proposed. The model can be predict BitTorrent traffic. The traffic was calculated with the model, and compared with real BitTorrent traffic, the error was small. The model can be used to predict the BitTorrent traffic.
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    • Fast Method of DOA Estimation Using Fractal Antenna Arrays
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 88-91. DOI:10.13190/jbupt.2007s1.88.wangdw
    • Abstract ( 2175 )     HTML       
    • Fractal antenna arrays and rank-reducation are discussed in the paper. Then a fast Method of DOA Estimation Using Cantor linear arrays is proposed. Given the training sequences of a desired signal, the signal subspace and noise subspace can be obtain quickly, while the dimension of subspace can be correctly estimated. The new method does not require the formation of the covariance matrix and its eigendecomposition. So it outperforms the eigen-decomposition based method in terms of computational complexity. And the size of Cantor linear arrays is only 70% of general antenna arrays. Finally, the effectiveness of the proposed approach is verified by numerical results.
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    Papers

    • An Adaptive Multihop Cellular Network Model
    • FANG Ya-Ding SONG Me SONG Jun-De
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 92-95. DOI:10.13190/jbupt.2007s1.92.123
    • Abstract ( 2457 )     HTML       
    • An adaptive cellular multihop network model is proposed. Based on a dynamic network mode switching mechanism, the terminal in this model can switch work mode between cellular and multihop according to the network performance. This model combines the advantages of the cellular and multihop to promote the transmission performance efficiently. The simulation result shows that this model enables a higher throughput, lower power consumption and better fairness.
    • Supplementary Material | Related Articles

    Reports

    • A Queue Scheduling Algorithm based on Paris Metro Pricing
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 105-108. DOI:10.13190/jbupt.2007s1.105.xuht
    • Abstract ( 2004 )     HTML       
    • A simple and efficient queue scheduling algorithm based on paris metro pricing is presented which is for the DiffServ in the commercial network . Price is as one of the ways to differentiate the priority. This paper prove that the strict guarantee of delay and the optimal revenue can be obtained through updating weight and call admission control. Finally,the performance of the solution is evaluated through simulation experiments.
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    • The Research of Key Management Architecture for MANET with Virtual Infrastructure
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 109-113. DOI:10.13190/jbupt.2007s1.109.sunb
    • Abstract ( 1682 )     HTML       
    • Group keys have been applied to mobile Ad Hoc networks (MANET) to assure secure communication. This paper presents key management architectures for MANET with two-layered and three-layered virtual infrastructure. The analysis showed that (1) the distributed-centralized architecture is more suitable for two-layered MANET, when the leaf nodes averagely located under each gateway node, the rekey messages would be optimized; (2) when the number of the first layer gateway nodes keep in a small scale, the two-distributed-one-centralized key management architecture is more suitable for three-layered MANET. (3) Based on the same condition, the three layered key management architecture will achieve less communication cost comparing with the two layered ones. We optimized the MANET virtual infrastructure protocol with these conditions. The simulation results showed that it can improve the communication efficiency.
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    • Resource Partitioning Algorithm for Access Network Design
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 118-121. DOI:10.13190/jbupt.2007s1.118.lufm
    • Abstract ( 1648 )     HTML       
    • The basic principle of Resource Partitioning Algorithm[1,2] is to apply the idea of partitioning to the network topology design. In this paper, we modify the original Resource Partition Algorithm by redefining two key parameters, i.e., length tolerance and hop-count limit, in order to optimize the design of access network topology. We also present the experiment on an example access network to illustrate the efficacy of our algorithm.
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    • Study on Scheme Realizing OCDMA over WDM-PON
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 122-125. DOI:10.13190/jbupt.2007s1.122.yanglw
    • Abstract ( 2196 )     HTML       
    • The structure of OCDMA over WDM-PON system was proposed, the performance of this system was analyzed. The simulation results show that when OCDMA and WDM were combined in passive optical network by inserting a group of OCDMA subscribers in each WDM channel, the number of subscribers can satisfy the demand easily, and the performance of the system can be guaranteed.
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    Papers

    • Collaborative Spectrum Allocation Algorithm of Cognitive Radio Network
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 126-130. DOI:10.13190/jbupt.2007s1.126.guocl
    • Abstract ( 2702 )     HTML       
    • Dynamic collaborative spectrum allocation optimization of cognitive radio network is studied in this paper. A spectrum allocation model based on graph coloring theory is proposed. For an immutable topology, weighted distributed greedy algorithm, fairness based distributed greedy algorithm and improved randomized distributed algorithm are proposed for optimizing throughput, fairness and collaborative overhead respectively. For a mutable topology, a fast channel adjustment algorithm is proposed. Experimental results show that the algorithm reduces communication costs remarkably while providing good performance in throughput and fairness.
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    Reports

    • A Method for Blind Detection of OFDM Signal Based on Cepstrum Processing
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 137-140. DOI:10.13190/jbupt.2007s1.137.zhanghy
    • Abstract ( 1868 )     HTML       
    • A method for Blind Detection of OFDM Signal Based on Cepstrum Processing is presented, which makes use of hidden periodicity of OFDM spectrum and has strong ability to bate the add interference and multiply interference so as to identify OFDM signals at lower signal/noise ratio. It not only can accurately estimate the sub-carrier frequency interval, symbol periods, bandwidth and sub-carrier numbers of OFDM signals but also has lower computational complexity and more accurate estimation, which are proper for hardware implement. The simulations further demonstrate the effectivity of our scheme.
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    • A Data Coding Method for RFID System
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 141-144. DOI:10.13190/jbupt.2007s1.141.zhengf
    • Abstract ( 1964 )     HTML       
    • For carrying out more energy to passive tag, a modified-Manchester coding is presented for RFID system in this paper. The basic idea of this coding is to provide more high level duration within a symbol cycle. The merits of being easy to synchronize and extract timing clock is still kept down. The cost of carrying more energy is that the frequency spectrum is widened.
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    • Adaptive pulse design based on PSWFs for UWB
    • Journal of Beijing University of Posts and Telecommunications. 2007, 29(s1): 145-148. DOI:10.13190/jbupt.2007s1.145.chengd
    • Abstract ( 2039 )     HTML       
    • This paper gave a scheme of dynamically obtaining adaptive emission mask based on spectrum sensing to adapt to spectrum environment and be compatible with FCC spectral mask. Then, a method to generate adaptive UWB shaping pulse was proposed based on weight combination of prolate spheroidal wave functions(PSWFs) matching UWB multiple sub-band spectral mask. The simulation results show that the pulse waveforms shaped by this method conform the spectral mask constraint for UWB, and adapt to dynamical variety of the spectral mask .
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