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Relaying Selection with Network-coded Cooperative Protocols in Aeronautical Communications

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Chinese Journal of Aeronautics 2010年第1期23卷 75-83页

作者： Du Bing,Zhang Jun school of electronics and information Engineering,Beijing University of Aeronautics and Astronautics,Beijing 100191,China [a] school of electronics information Engineering Beijing University of Aeronautics Astronautics Beijing 100191 China

In this article, we exploit the idea of network-coded cooperative protocol in aeronautical communications which combines different source nodes＇ information at the relay and joint decoding at the destination. Recently, the network coding in cooperative communications has been categorized into two mainstreams, bit-level and signal-level combinations, which are both discussed in the article. And to be exclusively,multiple access relay channel（MARC） is adopted. The mutual information expressions of both above-cited network-coded protocols are deduced, which prove that without proper selected relays to perform network coding, the spatial diversity of the proposed protocol cannot be obtained. This then leads to search for the selection and grouping algorithms. An adjacency matrix is defined to describe the connectivity of the nodes in one radio contact disk, so that, the selection and grouping of algorithm is equivalent to constructing this adjacency matrix to minimize the system outage probability evaluated in term of the mutual information. Besides, a network-coded cooperative protocol requires the acyclic network, of which the construction is to avoid loop-4 in the matrix. The article ends with simulations to demonstrate the viability of the proposed algorithms.

关键词： communication network coding outage probability mutual information bit-level signal-level

Digital Cancellation Scheme and Hardware Implementation for High-Order Passive Intermodulation Interference Based on Hammerstein Model

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China Communications 2019年第9期16卷 165-176页

作者： Xiaqing Miao Lu Tian school of information and electronics Beijing Institute of TechnologyBeijing 100081China China Academy of electronics and information Technology Beijing 100041China

Passive intermodulation(PIM)interference urgently needs to be solved in the satellite communication system,owing to degrading the whole *** research contributions to the cancellation method for PIM were focused on the analog domain,however,the PIM distortion cannot be eliminated completely with the ***,some researchers attempt to tackle the problem through digital signal processing,nevertheless,the proposed methods were not suitable for the practical satellite communication *** this paper,we present a general scheme for the adaptive feedforward PIM ***-order PIM signals at baseband are estimated by modeling the PIM distortion with Hammerstein model in the digital *** on the reconstructed PIM signal,we adopt the least mean square algorithm to adaptively mitigate the PIM interference for tracking the variation of *** time and frequency synchronization of PIM are based on the correlation of the peak of received signals with the corresponding reconstructed PIM *** experimental results show that the scheme can effectively cancel the PIM interference,and achieve an interference suppression gain more than 20dB.

关键词： satellite communication passiveintermodulation interference digital cancellation Hammerstein model

An accurate SISAR imaging method of ground moving target in forward scatter radar

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Science China(information Sciences) 2012年第10期55卷 2269-2280页

作者： HU Cheng 1,LI XiaoLiang 1,2,LONG Teng 1 & ZHOU Chao 3 1 school of information and electronics,Beijing Institute of Technology,Beijing 100081,China 2 Communication Station,Chinese People's Armed Police Force,Beijing 100089,China 3 school of electronics and information,Soochow University,Suzhou 215.21,China 1. school of information and electronics Beijing Institute of Technology Beijing 100081 China 2. Communication Station Chinese People’s Armed Police Force Beijing 100089 China 3. school of electronics and information Soochow University Suzhou 215021 China

In order to accurately extract the profile image of the ground moving targets(GMT) in the forward scatter radar(FSR),a forward scatter signal model of GMT is built based on the Fresnel-Kirchhoff diffraction formula,the multipath propagation model and the high order phase approximation *** classical shadow inverse synthetic aperture radar(SISAR) imaging algorithm is modified using the proposed signal *** the modified imaging algorithm,the impacts of ground reflection,non-linear variation of target Doppler frequency and the target motion direction on imaging accuracy are ***,non-linear and time-dependent parameters are used to compensate for the motion phase of the GMT forward scatter signal,and a novel estimation method of the height difference and median line height of the target profile is put forward under the multipath ***,both the accuracy of the proposed signal model and the effectiveness of the modified imaging algorithm are validated by the simulation results.

关键词： shadow inverse synthetic aperture radar ground moving target signal model multipath interference imaging algorithm

Binary particle swarm optimization with multiple evolutionary strategies

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Science China(information Sciences) 2012年第11期55卷 2485-2494页

作者： ZHAO Jing1,HAN ChongZhao1 & WEI Bin2 1Ministry of Education Key Lab For Intelligent Networks and Network Security,State Key Laboratory for Manufacturing Systems Engineering,Institute of Integrated Automation,school of electronics and information Engineering,Xi'an Jiaotong University,Xi'an 710049,China 2Institute of System Engineering,school of electronics and information Engineering,Xi'an Jiaotong University,Xi'an 710049,China 1. Ministry of Education Key Lab For Intelligent Networks and Network Security State Key Laboratory for Manufacturing Systems Engineering Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. Institute of System Engineering School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China

This paper introduces a novel variation of binary particle swarm optimization(BPSO) algorithm and a further extension to improve its ***,mimicking the behaviors of some creatures group,multiple evolutionary strategies BPSO(MBPSO) is introduced which takes different evolutionary strategies for various particles according to their ***,on the basis of MBPSO,a new strategy is discussed to improve the performance of the MBPSO(M2BPSO) which adopts the concept of the mutation operator aiming to overcome the premature convergence and slow convergent speed during the later stages of the *** proposed two algorithms are tested on seven benchmark functions and their results are compared with those obtained by other *** results show that our methods outperform the other algorithms.

关键词： binary particle swarm optimizer evolutionary strategies swarm intelligence

Performance analysis of network coding for multicast relay system over Nakagami-m fading channels

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Science China(information Sciences) 2011年第11期54卷 2338-2348页

作者： ZHAO Rui 1,YANG LvXi 2 & HUANG YongMing 2 1 school of information Science and Engineering,Huaqiao University,Xiamen 361021,China 2.school of information Science and Engineering,Southeast University,Nanjing 210096,China 1. school of information Science and Engineering Huaqiao University Xiamen 361021 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

The outage probability performance of network coding for multicast relay system is analyzed in Nakagami-m fading *** transmission strategies,i.e.,complex field network coding (CFNC) and amplify-and-forward network coding (AFNC),are applied in the system,and the approximate expressions of outage probability are derived at high SNR and the conclusion is reached that the system diversity gains of two transmission strategies are both 2m,as is verified by numerical *** results also show that CFNC can outperform both AFNC and direct transmission without relay in the performances of system outage probability,sum rate and symbol error ratio.

关键词： multicast relay system network coding outage probability diversity gain

An improved reduced-rank STAP interference suppression method in design of GNSS receivers

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Science China(information Sciences) 2012年第10期55卷 2329-2342页

作者： GONG WenFei & SUN Xin school of electronics and information Engineering,Beijing Jiaotong University,Beijing 100044,China 1. school of electronics and information Engineering Beijing Jiaotong University Beijing 100044 China

In this paper,we address the problem of interference cancellation in global positioning system(GPS) receiver using an adaptive reduced-rank space-time adaptive processing(STAP) interference suppression method based on multistage nested Wiener filter(MSNWF).This improved adaptive reduced-rank method is based on the improved Gerschgorin radii ***,the cross-correlations between the desired signals of the adjacent stages of MSNWF are directly used to calculate the Gerschgorin radii instead of employing the eigenvalue decomposition of the covariance ***,a heuristic decision rule based on Gerschgorin disk estimator(GDE) is employed to estimate the rank of interference *** optimal rank can be adaptively selected without increasing the *** and results of the experiment show that the proposed method further reduces the computation of STAP and enhances its real-time property with the interference suppression performance unaffected.

关键词： global positioning system reduced-rank space-time adaptive processing multistage nested Wiener filter Gerschgorin disk estimator

A fast local routing repair scheme for wireless mobile ad hoc network

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Science China(information Sciences) 2011年第1期54卷 111-122页

作者： QIN DanYang,SHA XueJun & XU YuBin electronics and information Engineering school,Harbin Institute of Technology,Harbin 15.001,China 1. electronics and information Engineering school Harbin Institute of Technology Harbin 150001 China

Mobile ad hoc network(MANET)is a centerless packet radio network which does not use fixed *** has recently received tremendous attention due to its capabilities of self-configuration and ***,attenuation and interference caused by node mobility and wireless channel sharing weaken the stability of communication links.A mathematical exploring model for the next hop has been established based on the optimal exploring *** negative impact of wireless routes discontinuity has been alleviated by a novel fast local routing repair scheme(FLRRS)proposed in this paper,wherein the route requirement zone has been restricted into a pie slice region on intermediate nodes according to the solution of exploring *** scheme is an effective approach in reducing the average end-to-end delay during routing *** also allows continuous packet forwarding for fault ***-2 based simulation results showed remarkable successful packet delivery rate and end-to-end delay improvements of source-initiated routing protocol with the fast local repair scheme,especially in the case of high dynamic environments with heavy traffc loads.

关键词： FLRRS optimal exploration parabolic partial differential equation fault resilience MANET

Some notes on betting commitment distance in evidence theory

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Science China(information Sciences) 2012年第3期55卷 558-565页

作者： HAN DeQiang1 , DENG Yong2, HAN ChongZhao1 & YANG Yi3 1MOE KLINNS Lab, SKLMSE Lab, Institute of Integrated Automation, school of electronics and information Engineering, Xi’an Jiaotong University, Xi’an 710049, China 2school of electronics and information Technology, Shanghai Jiaotong University, Shanghai 200240, China 3school of Aerospace, Xi’an Jiaotong University, Xi’an 710049, China 1. MOE KLINNS Lab SKLMSE Lab Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an 710049 China2. School of Electronics and Information Technology Shanghai Jiaotong University Shanghai 200240 China3. School of Aerospace Xi’an Jiaotong University Xi’an 710049 China

The distance of evidence, which represents the degree of dissimilarity between bodies of evidence, has attracted more and more interest and has found extensive uses in many realms. In this paper some notes on a widely used distance of evidence, i.e., betting commitment distance, are provided, including the arguments on the rationality of its definition, some misuses and some counter-intuitive behaviors of betting commitment distance. Several numerical examples are also provided to support and verify our arguments.

关键词： pignistic probability evidence theory betting commitment distance distance of evidence

Inferring playback rate and rate resets of P2P video streaming transmissions by piecewise line envelope approximation

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The Journal of China Universities of Posts and Telecommunications 2009年第2期16卷 58-62,79页

作者： LI Chun-xi CHEN Chang-jia school of electronics and information Engineering,Beijing Jiaotong University,Beijing 100044,China [a]school of electronics and information Engineering Beijing Jiaotong University Beijing 100044 China

Conventionally, P2P video is regarded as CBR traffic. However, our measurements have shown that the rate reset cannot be neglected in a practical IPTV system because each rate reset often leads to performance degradation. Thus, addressing the problem of inferring playback rate and rate reset in a P2P video system is significant. In this article, an algorithm termed piecewise linear envelope approximation （PLEA） is proposed, in which a follow-up time is introduced to smooth rate fluctuations in a small time scale and to adapt rate jumps in a large time scale automatically. With the PLEA algorithm, discontinuity introduced by blind segmentations adopted by current methods is avoided. Furthermore, unlike existing algorithms in which both segmentation and combinations are performed in multiple runs, only a single computation path is involved in the PLEA algorithm. This makes PLEA algorithm amenable to implementation of low complexity by either software or hardware. Both theoretical analysis and experiment based on measured data show that the PLEA outperforms existing algorithms based on segmentation.

关键词： P2P video playback rate rate reset convex hull linear program