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Single link tracking scheme based on UWB localization

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1207-1212页

作者： Xiao Zhu Xiong Hailiang Yu Quan yi kechu State Key Lab. of Integrated Service Networks Xidian Univ. Xi'an 710071 P. R. China School of Electronic Science and Engineering National Univ. of Defense Technology Changsha 410073 P. R. China Inst. of China Electronics Equipment System Engineering Corporation Beijing 100039 P. R. China

To investigate the low-complex and high-precise tracking method, a novel single link tracking scheme based on UWB localization is proposed. Two antenna arrays are settled at the fixed station （FS） to receive the UWB signal from mobile terminal （MT）, one FS is enough for the proposed scheme to track the MT. The UWB multipath detection algorithm for time difference of arrival （TDOA） estimation is presented and TDOA is thus adopted to estimate angle of arrival （AOA）, avoiding the synchronization and complicated beamforming for AOA. The impacts of localization errors, concluding multipath and non-line-of-sight （NLOS） errors are simulated for the proposed track scheme. It is demonstrated that the simulation curve can match the real target moving, and the feasibility of the proposed scheme is proved.

关键词： ultra-wide band localization single-link tracking angle of arrival estimation.

Outage Performance of Cognitive AF Relay Networks with Imperfect CSI Based on Geometrical Analysis

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Chinese Journal of Electronics 2017年第5期26卷 1048-1056页

作者： LIU Shuai SUN Dechun LIU Zujun yi kechu YANG Hong WANG Kan State Key Laboratory of Integrated Services Networks Xidian University China Academy of Space Technology

This paper studies the outage performance of a cognitive Amplify-and-forward(AF) relay network subject to Rayleigh *** the condition of imperfect Channel state information(CSI) estimations of the links from the secondary system to the Primary user(PU),the closed-form upper and lower bounds of the outage probability are derived through a geometrical analysis *** asymptotic analysis of the outage probability is also derived in the high Signal-to-noise ratio(SNR)regime to gain additional insights on the *** simulation results corroborate our theoretical analysis,and the effectiveness of the geometrical analysis method is verified with the conventional approach as a *** asymptotic results are very tight with the analytical lower bound in the high SNR *** also can be observed from the simulation results that the impact of the number of relays as well as the imperfect CSI on the outage probability and the diversity order.

关键词： Cognitive relay networks Imperfect Channel state information(CSI) Geometrical analysis

Research on positioning enhancement scheme of CAPS via UWB pseudolite

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 733-737页

作者： XIAO Zhu BAI Jing MA Guanyi FAN JiangTao yi kechu College oflnformation Science and Engineering Hunan UniversityChangsha 410082China State Key Laboratory oflntegrated Service Networks Xidian UniversityXi'an 710071China Key Laboratory oflntelligent Perception and Image Understanding of Ministry of Education Xidian UniversityXi'an 710071China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

The positioning precision of the transmitting Chinese Area Positioning System(CAPS) is reduced due to the non-ideal distribution of the satellite *** and navigation enhancement methods are able to improve the reliability and accuracy of the positioning system,especially for users in special regions and special *** this paper,a positioning enhanced scheme based on ultra-wide band(UWB) pseudolite is proposed for *** is demonstrated that the link budget of UWB pseudolite satisfies the FCC's emission mask *** localization algorithm of the enhanced CAPS is *** simulations indicate that the positioning precision of the proposed enhanced scheme is improved greatly,and the feasibility of the enhanced scheme is thus proved.

关键词： CAPS UWB positioning enhancement pseudolite

Packet routing algorithm for polar orbit LEO satellite constellation network

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Science in China(Series F) 2006年第1期49卷 103-127页

作者： WANG Kaidong yi kechu TIAN Bin WU Chengke National Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China School of Computer Science Xidian University Xi'an 710071 China

Broadband satellite networks are capable of providing global coverage and support various services. The networks constructed by Low Earth Orbit （LEO） satellite constellations have attracted great interests because of their short round-trip delays and wide bandwidths. A challenging problem is to develop a simple and efficient packet routing algorithm for the LEO satellite constellation network. This paper presents a SpiderWeb Topological Network （SWTN） and a distributed packet routing algorithm for the LEO satellite constellation network based on the SWTN. The algorithm gives the minimum propagation delay paths with low computational complexity and requires no routing tables, which is practical for on-board processing. The performance of the algorithm is demon- strated through simulations.

关键词： packet routing LEO satellite constellation satellite networks SWTN.

Novel scheduling strategy for downlink multiuser MIMO system: Particle swarm optimization

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Science in China(Series F) 2009年第12期52卷 2279-2289页

作者： HEI YongQiang LI XiaoHui yi kechu YANG Hong State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071 China

In this paper the scheduling problem in downlink multiuser MIMO system is described as an optimization problem and particle swarm optimization （PSO） algorithm is introduced to address such problem. Two PSO scheduling methods with different objective functions applicable to different requirements on capacity and complexity are investigated. One is the capacity based PSO（C-PSO） scheduling method aiming at achieving the near optimal capacity; and the other is the lower bound of eigenvalue based PSO （LBE-PSO） scheduling method with the purpose of reducing computational complexity and at the same time achieving as large as possible capacity gain. Furthermore, convergence analysis of PSO from both the particle and the velocity aspects is also presented to derive the convergent condition, which is validated by several examples of different parameter values. Simulation results reveal that the C-PSO can obtain nearly the same capacity as the exhaustive search method with lower complexity, while the LBE-PSO provides a viable approach by striking a better tradeoff between capacity and computational complexity.

关键词： multiuser MIMO scheduling downlink transmission particle swarm optimization

On the Performance of Wireless-Powered Cooperative DF Relaying Networks with Imperfect CSI

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China Communications 2018年第11期15卷 79-92页

作者： Shuai Liu Zujun Liu Dechun Sun Hong Yang kechu yi Kan Wang tate Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071 China China Academy of Space Technology Beijing 100094 China Faculty of Computer Science and Engineering Xi'an University of Technology Xi'an 710048 China

This paper studies several performance metrics of a wireless-powered decode-and-forward(DF) relay network with imperfect channel state information(CSI). In particular, based on the time switching(TS) protocol, the energy-constrained relay harvesting energy from a power beacon(PB), and uses that harvested energy to forward the source information to destination. The closedform expression of the outage probability is firstly derived over Rayleigh fading channels. Then, the asymptotic analysis, throughput as well as the symbol error probability(SEP) are derived based on the expression of the outage probability. Next, both transmission power of the source and the power beacon are optimized through the throughput optimization. Finally, simulations are conducted to corroborate our theoretical analysis, and to reveal the impact of the transmission power of the source and PB as well as the imperfect CSI on the system performance.

关键词： energy harvesting imperfectchannel state information time switching per-formance analysis

Outage performance of cognitive multisource multidestination relay networks with imperfect channel state information and interference from primary transmitter

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High Technology Letters 2019年第4期25卷 369-377页

作者： Liu Shuai Sun Dechun Liu Zujun yi kechu Yang Hong Wang Kan State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071P.R.China China Academy of Space Technology Beijing 100094P.R.China Faculty of Computer Science and Engineering Xi’an University of TechnologyXi’an 710048P.R.China

Given imperfect channel state information(CSI)and considering the interference from the primary transmitter,an underlay cognitive multisource multidestination relay network is proposed.A closed-form exact outage probability and asymptotic outage probability are derived for the secondary system of the *** results show that the outage probability is influenced by the source and destination number,the CSI imperfection as well as the interference from the primary transmitter,while the diversity order is independent of the CSI imperfection and the interference from the primary transmitter,yet it is equal to the minimum of the source and destination ***,extensive simulations are conducted with different system parameters to verify the theoretical analysis.

关键词： outage performance cognitive network channel state information(CSI) primary transmitter

FAST PRACTICAL DESIGN OF 2-D DIGITAL FILTERS

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Journal of Electronics(China) 1987年第2期4卷 105-111页

作者：易克初 Northwest Telecommunication Engineering Institute

This paper discusses a simple method for designing 2-D digital *** method can give linearphase 2-D filters with rather low computation cost,and can be generalized to multi-dimensional *** are given to show its practic... 详细信息

关键词： FIR FAST PRACTICAL DESIGN OF 2-D DIGITAL FILTERS exp IIR

THE STUDY OF A BOCC M-ARY SPREAD SPECTRUM SCHEME

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Journal of Electronics(China) 2005年第5期22卷 449-457页

作者： Chu Zhenyong ying Xiaofan Tian Hongxin yi kechu State Key Lab of ISN Xidian University Xi＇an 710071 China

M-ary spread spectrum technique has been found wide applications in wireless communications, but it needs too many orthogonal spreading codes and its despreading/demodulation is quite complex computationally, which limit its wider applications. This paper proposes a novel scheme for Code Division Multiple Access (CDMA) communication systems based on M-ary spread spectrum, where only one prototype spreading code is assigned to each user and the codes for different users are orthogonal or quasi-orthogonal with each other. The M spreading codes of each user to represent K bits data are generated by circularly shifting the assigned code and reversing its polarity. The spreading codes generated like that are called as BiOrthogonal Cyclic Codes (BOCCs). At the receiver of the system, a transform domain matched-filter implemented by means of Fast Fourier Transform (FFT) is employed to despread and demodulate the received signals, which has very low computational complexity. The results of simulation experiments and bit-error performance analysis show that the proposed scheme is practical and very useful in many cases.

关键词： M-ary spread spectrum BiOrthogonal Cyclic Codes (BOCCs) Satellite communication Transform domain processing