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TD-AltBOC:A new COMPASS B2 modulation

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Science China(Physics,Mechanics & Astronomy) 2011年第6期54卷 1014-1021页

作者： TANG ZuPing ZHOU Hongwei wei jiaolong YAN Tao LIU YuQi RAN YiHang ZHOU YanLing Department of Electronics and Information Engineering Huazhong University of Science and TechnologyWuhan 430074China Beijing Institute of Tracking and Telecommunication Technology Beijing 100094China

AltBOC(15,10) is the baseline of COMPASS B2 signal *** is a BOC-like signal having different PN codes in the lower and the upper main split lobes,which allow one signal service per *** two lobes can be received and processed separately like two BPSK(10) signals,or coherently processed to achieve better *** among COMPASS B2,Galileo E5 and GPS L5 is also achievable using AltBOC ***,Galileo's 4-code AltBOC has drawbacks such as low efficiency and great receiver *** paper presents a new modulation type named TD-AltBOC (Time Division AltBOC).The signal generation scheme and receiving method are presented,and are compared with AltBOC in the areas of power spectrum,ranging accuracy,anti-multipath performance,anti-interference performance,processing flexibility and *** results show TD-AltBOC has similar spectrum characteristics,interoperability,flexibility and anti-interference performance with *** the frontend bandwidth is more than 50 MHz,TD-AltBOC can achieve better ranging accuracy and anti-multipath *** also has such advantages as high efficiency and low receiver ***-AltBOC could be a good solution to COMPASS B2 navigation signal.

关键词： GNSS COMPASS signal structure TD-AltBOC signal modulation

Analysis of Multipath and CW Interference Effects on GNSS Receivers with EMLP Discriminator

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Communications and Network 2013年第3期5卷 80-85页

作者： Bo Qu jiaolong wei Shuangna Zhang Liang Bi Department of Electronic and Information Engineering Huazhong University of Science and Technology China Space Star Technology Co. Ltd China

Multipath and continuous wave (CW) interference may cause severe performance degradation of global navigation satellite system (GNSS) receivers. This paper analyzes the code tracking performance of early-minus-late power (EMLP) discriminator of GNSS receivers in the presence of multipath and CW interference. An analytical expression of the code tracking error is suggested for EMLP discriminator, and it can be used to assess the effect of multipath and CW interference. The derived expression shows that the combined effects include three components: multipath component;CW interference component and the combined component of multipath and CW interference. The effect of these components depends on some factors which can be classified into two categories: the receiving environment and the receiver parameters. Numerical results show how these factors affect the tracking performances. It is shown that the proper receiver parameters can suppress the combined effects of multipath and CW interference.

关键词： Analysis of Multipath and CW Interference Effects on GNSS Receivers with EMLP Discriminator

An Asynchronous Observation Positioning Algorithm Based on Factor Graph Optimization

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An Asynchronous Observation Positioning Algorithm Based on F...

第十四届中国卫星导航年会

作者： Chuang Zhou jiaolong wei Zuping Tang Huazhong University of Science and Technology

Broadcasting integrated signal of communication and navigation in low earth orbiting(LEO) broadband constellation to achieve the navigation augmentation is an existing *** the needs of communication services,the integrated signal generally has burst characteristics,and the receiver only receives the signal from the satellite in some specific time slots,and the observation has obvious asynchronous arrival *** asynchronous arrival observations are quite different from the synchronous observations obtained by receiving the continuous navigation signals broadcast by the existing GNSS satellites,which will lead to many problems if using the traditional positioning *** the characteristics of asynchronous observations,this paper proposes an asynchronous observation positioning algorithm based on factor graph optimization(FGO),which can use asynchronous observation in multiple epochs for joint estimation to reduce positioning *** shows that the positioning algorithm based on FGO can effectively improve the positioning accuracy compared with the traditional method.

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基于灰色粒子群神经网络的航天器参量预测

数据采集与处理 2014年第5期29卷 828-832页

作者：顾胜魏蛟龙北京航天飞行控制中心北京100094 华中科技大学电子与信息工程系武汉430074

针对航天器精确预测与健康管理的需求,将粒子群算法、灰色理论与神经网络的优势相结合,提出了一种灰色粒子群神经网络组合参量预测方法,实现了灰色模型、粒子群算法、神经网络模型的优势互补。针对某卫星南帆板输出电流参量的预测实例,... 详细信息

针对航天器精确预测与健康管理的需求,将粒子群算法、灰色理论与神经网络的优势相结合,提出了一种灰色粒子群神经网络组合参量预测方法,实现了灰色模型、粒子群算法、神经网络模型的优势互补。针对某卫星南帆板输出电流参量的预测实例,采用总平均绝对误差、总平均绝对百分比误差、总均方根误差3个预测结果评价指标,对灰色粒子群神经网络模型、粒子群神经网络模型、灰色模型和残差修正灰色模型的预测结果进行了比较,结果证明灰色粒子群神经网络模型的预测精度较高,在航天器参量预测领域具有很好的应用前景。

关键词：航天器粒子群优化灰色理论神经网络

Anti-multipath localization method based on MEDLL and WLS

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Anti-multipath localization method based on MEDLL and WLS

第十四届中国卫星导航年会

作者： Yuan Feng Jingyuan Xa jiaolong wei Zuping Tang Huazhong University of Science and Technology

Aiming at the influence of multipath effect on positioning accuracy,this paper proposes an anti-multipath positioning method based on MEDLL and ***,a multipath detection index MDCR was proposed based on MEDLL multipath detection method,and its indicator of multipath interference was compared with SAM,CNR,***,combining the correlation coefficients between these four indexes and the pseudo-distance multipath error and the fuzzy comprehensive evaluation method,a WLS localization algorithm based on multipath detection is *** results show that the positioning error of the proposed algorithm is better than that of the weighted positioning algorithm based on elevation Angle in both horizontal direction and 3D position under both static and dynamic multi-path conditions.

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Correlation side-peaks cancellation technique for Sine-BOC signal tracking

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Correlation side-peaks cancellation technique for Sine-BOC s...

第五届中国卫星导航学术年会

作者： Bo Qu jiaolong wei Zuping Tang Tao Yan The Department of Electronics and Information Engineering of Huazhong University of Science and Technology

ISBN: (纸本)9783642547362

With the development of GNSS systems, BOC modulation signal has been widely used in the modernized GPS, Galileo, and Beidou. BOC signal has the split power spectrum density （PSD）, which has better compatibility with GPS C/A signal. Furthermore, the PSD of BOC signal has more high frequency components, which results in better code tracking performance and multipath mitigation performance than BPSK signal. Because of the sub-carriers, the autocorrelation function （ACF） of BOC modulation signal has a main peak and some side peaks. The traditional delay locked loop （DLL） may be locked on the side peaks of ACF, which causes the extra tracking error. In this paper, an unambiguous tracking method is proposed for BOC modulation signal. The received BOC signal is correlated with two different local reference signals with the tailored waveform to obtain correlation outputs. Then the correlation outputs are combined to eliminate side peaks and obtain the combined correlation with one peak. The early minus late power （EMLP） discriminator can be used to lock on the sole peak of the combined correlation function. This unambiguous tracking techniques has been analyzed for BOC （1,1） signal in the simulation. The simulation results show that this technique can achieve the unambiguous tracking for BOC signal and maintain the same level of the tracking performance as the traditional tracking loop.

关键词： GNSS BOC modulation signal unambiguous tracking delay locked loop

Vulnerability Assessment for GNSS Constellation Based on AHP-FCE

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Vulnerability Assessment for GNSS Constellation Based on AHP...

第四届中国卫星导航学术年会

作者： Bo Qu jiaolong wei Shuangna Zhang Liang Bi The Department of Electronic and Information Engineering of Huazhong University of Science and Technology Space Star Technology Co. Ltd

The vulnerability of global navigation satellite system （GNSS） constellation is an important part of the vulnerability of GNSS. The vulnerability assessment for GNSS constellation is helpful to improve GNSS constellation. In this paper, the vulnerability of GNSS constellation is investigated and a vulnerability assessment model for GNSS constellation is suggested, then the vulnerability of GNSS constellation is evaluated by Analytical Hierarchy Process and Fuzzy Comprehensive Evaluation （AHP-FCE）. The suggested assessment model concerns about the coverage of GNSS constellation in the situations that 1 satellite, 2 satellites, and 3 satellites are failure, and the mean coverage of GNSS constellation which is affected by satellite failures is used to be the assessment criterions. The vulnerability values of GNSS constellation can be calculated by AHP-FCE according to these criterions. In this paper, the vulnerability of GPS constellation and COMPASS constellation are evaluated, and the assessment results show that GPS constellation is slightly more vulnerable than COMPASS constellation which has more redundant satellites.

关键词： vulnerability GNSS Constellation AHP FCE assessment

Performance Analysis on Single Sideband of TD-AltBOC Modulation Signal

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Performance Analysis on Single Sideband of TD-AltBOC Modulat...

第四届中国卫星导航学术年会

作者： Tao Yan jiaolong wei Zuping Tang Zhihui Zhou The Department of Electronic and Information Engineering of Huazhong University of Science and Technology

TD-AltBOC modulation signal is a new signal. Similar to AltBOC（15,10） signal , TD-AltBOC signal contains lower and upper sideband signals. From the view of the selection of PN codes for lower and upper sideband signals’ pilot components, there are two schemes to achieve TD-AltBOC, namely to choose different PN codes or the same PN code. For considering the cost and complexity of receivers, only the lower sideband signal may be received for mass market receivers. When the receiver is only tracking lower sideband signal’s pilot component, due to the non-ideal PN codes and the effect of upper sideband signals, a asymmetrical correlation function may be obtained, which causes the cross zero point of discriminator curve to move, so code tracking bias error is introduced. In this paper, we analyze the reason and condition why correlation function is asymmetry, and make performance analysis on single sideband of TD-AltBOC modulation Signal. Simulation results show that the selection of PN codes for data component may cause correlation function asymmetry. In order to reduce the effect on single sideband reception and reach the same performance with AltBOC（15,10）, the selection of PN codes has to meet requirement of this paper.

关键词： TD-AltBOC PN code Code tracking bias error

UNIFORM-PRICE AUCTION FOR BANDWIDTH ALLOCATION IN THE INTERNET

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Journal of Electronics(China) 2002年第4期19卷 408-414页

作者： wei jiaolong Zhang Chi (Dept. of Electron, and Information, lluazhong Univ. of Science and Technology, Wuhan 430074) Dept. of Electron. and Information Huazhong Univ. of Science and Technology Wuhan

It has been widely accepted that auctioning which is the pricing approach with minimal information requirement is a proper tool to manage scare network resources. Previous works focus on Vickrey auction which is incentive compatible in classic auction theory. In the beginning of this letter, the faults of the most representative auction-based mechanisms are discussed. And then a new method called Uniform-Price Auction (UPA), which has the simplest auction rule is proposed and its incentive compatibility in the network environment is also proved. Finally, the basic mode is extended to support applications which require minimum bandwidth guarantees for a given time period by introducing derivative market, and a market mechanism for network resource allocation which is predictable, riskless, and simple for end-users is completed.

关键词： Network resource allocation Usage-based pricing Incentive compatibility Vick-rey auction Smart market model Progressive second price auction Uniform-price auction Derivative mechanism