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面向航空搜救的无线电数据融合定位方法

无线电通信技术 2024年第1期50卷 25-31页

作者：白岩康廉保旺刘洋洋西北工业大学电子信息学院陕西西安710072

随着我国海洋经济事业的蓬勃发展,以及现代化战争中航空救援保障体系的急切需求,航空搜救定位技术越来越受到关注。基于无线电的航空搜救定位技术主要包含了测距、测向以及相应的多源融合技术。然而,搜救飞机上的起落架、轮胎等机载设... 详细信息

随着我国海洋经济事业的蓬勃发展,以及现代化战争中航空救援保障体系的急切需求,航空搜救定位技术越来越受到关注。基于无线电的航空搜救定位技术主要包含了测距、测向以及相应的多源融合技术。然而,搜救飞机上的起落架、轮胎等机载设备会对接收天线造成严重的遮挡、多径,给无线电测向带来较大误差。对此,基于贝叶斯滤波和群体智能理论,提出了一种基于稳健人工鱼群粒子滤波的无线电航空搜救数据融合定位方法。将粒子滤波中的粒子看作鱼群个体,通过模仿鱼群算法的觅食、群聚、追尾、随机游走行为来实现重采样步骤的优化,并且对行为中的搜索范围、寻优速度等方面做了改进,形成测距-测向融合定位算法。实际数据建模和仿真结果表明,所提的融合定位方法能够在较短的时间内达到较为准确的位置精度和角度精度,收敛性较强,具有良好的实时性和鲁棒性。

关键词：航空救援无线电测向人工鱼群融合定位

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Dual loop feedback pre-distortion in satellite communication

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Journal of Systems Engineering and Electronics 2013年第4期24卷 586-591页

作者： Chengkai Tang baowang lian Yi Zhang School of Electronics and Information Northwestern Polytechnical University

Since the satellite communication goes in the trend of high-frequency and fast speed, the coefficients updating and the precision of the traditional pre-distortion feedback methods need to be further improved. On this basis, this paper proposes dual loop feedback pre-distortion, which uses two first-order Volterra filter models to reduce the computing complexity and a dynamic error adjustment model to construct a revised feedback to ensure a better pre-distortion performance. The computation complexity, iterative convergence speed and precision of the proposed method are theoretically analyzed. Simulation results show that this dual loop feedback pre-distortion can speed the updating of coefficients and ensure the linearity of the amplifier output.

关键词： satellite communication pre-distortion Volterra filter dual loop feedback mean square error.

Weak GPS signal acquisition method based on DBZP

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Journal of Systems Engineering and Electronics 2018年第2期29卷 236-243页

作者： WANG Jianing lian baowang XUE Zhe School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Xi’an Modern Control Technology Research Institute Xi’an 710065China

Double block zero padding(DBZP) is a widely used but costly method for weak global positioning system(GPS) signal acquisition in software receivers. To improve the computational efficiency, this paper proposes an algorithm based on the differential DBZP algorithm and the discrete cosine transform(DCT) domain filtering method. The proposed method involves using a differential correlator after the DBZP operation. Subsequently, DCT domain low pass filtering(LPF) and inverse DCT(IDCT) reconstruction are carried out to improve the signal to noise ratio(SNR). The theoretical analysis and simulation results show that the detection algorithm can effectively improve the SNR of the acquired signal and increase the probability of detection under the same false alarm probability.

关键词： global positioning system(GPS) double block zero padding(DBZP) discrete cosine transform(DCT) differential coherent combing

Adaptive beamforming and phase bias compensation for GNSS receiver

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Journal of Systems Engineering and Electronics 2015年第1期26卷 10-18页

作者： Hongwei Zhao baowang lian Juan Feng School of Electronics and Information Northwestern Polytechnical University Shaanxi Fiber Home Communication Group Co. Ltd

Adaptive antenna arrays have been used to mitigate the interference on global navigation satellite system（GNSS） receivers. The performance of interference mitigation depends on the beamforming algorithms adopted by the antenna array. However,the adaptive beamforming will change the array pattern in realtime, which has the potential to introduce phase center biases into the antenna array. For precise applications, these phase biases must be mitigated or compensated because they will bring errors in code phase and carrier phase measurements. A novel adaptive beamforming algorithm is proposed firstly, then the phase bias induced by the proposed algorithm is estimated, and finally a compensation strategy is addressed. Simulations demonstrate that the proposed beamforming algorithm suppresses effectively the strong interference and improves significantly the capturing performance of GNSS signals. Simultaneously, the bias compensation method avoids the loss of the carrier phase lock and reduces the phase measurement errors for GNSS receivers.

关键词： global navigation satellite system(GNSS) space-time adaptive processing(STAP) adaptive beamforming bias compensation

Improved GNSS Cooperation Positioning Algorithm for Indoor Localization

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Computers, Materials & Continua 2018年第8期56卷 225-245页

作者： Taoyun Zhou baowang lian Siqing Yang Yi Zhang Yangyang Liu School of Electronics and Information Northwestern Polytechnical UniversityShaanxi710072China School of Information Hunan University of HumanitiesScience and TechnologyHunan417000China Radio Science Laboratory University of British ColumbiaVancouverCanada

For situations such as indoor and underground parking lots in which satellite signals are obstructed,GNSS cooperative positioning can be used to achieve highprecision positioning with the assistance of cooperative *** we study the cooperative positioning of two static nodes,node 1 is placed on the roof of the building and the satellite observation is ideal,node 2 is placed on the indoor windowsill where the occlusion situation is more serious,we mainly study how to locate node 2 with the assistance of node ***,the two cooperative nodes are located with pseudo-range single point positioning,and the positioning performance of cooperative node is analyzed,therefore the information of pseudo-range and position of node 1 is ***,the distance between cooperative nodes is obtained by using the baseline method with double-difference carrier ***,the cooperative location algorithms are *** Extended Kalman Filtering(EKF),Unscented Kalman Filtering(UKF)and Particle Filtering(PF)are used to fuse the pseudo-range,ranging information and location information *** to the mutual influences among the cooperative nodes in cooperative positioning,the EKF,UKF and PF algorithms are improved by resetting the error covariance matrix of the cooperative nodes at each update *** results show that after being improved,the influence between the cooperative nodes becomes smaller,and the positioning performance of the nodes is better than before.

关键词： Indoor localization GNSS cooperative positioning extended kalman filtering(EKF) unscented kalman filtering(UKF) particle filtering(PF)

室内惯性导航系统/相机拓扑测量的因子图合作定位算法

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西安交通大学学报 2020年第3期54卷 70-79页

作者：张琳廉保旺西北工业大学电子信息学院

为解决合作定位算法中滤波结构不易扩展、鲁棒性差的问题,提出了一种适应于室内多用户的惯性导航系统/相机拓扑测量的因子图合作定位算法。利用目标检测识别算法,提出相机拓扑测量合作定位算法。通过构建拓扑测量、惯性导航系统因子函数... 详细信息

为解决合作定位算法中滤波结构不易扩展、鲁棒性差的问题,提出了一种适应于室内多用户的惯性导航系统/相机拓扑测量的因子图合作定位算法。利用目标检测识别算法,提出相机拓扑测量合作定位算法。通过构建拓扑测量、惯性导航系统因子函数,推导出基于因子图的可扩展参数优化模型。为进一步提高鲁棒性,引入综合考虑残差和检测分数的权值判断法,提出适应于相机拓扑测量的改进型开关约束算法。仿真和实测实验表明:拓扑测量观测精度的提升对位置和速度估计、算法收敛次数均有不同程度的改善;合作+改进型开关约束算法的定位精度较非合作+非鲁棒算法的提高了79.8%;改进型开关约束算法相比原开关约束算法具有较高的预测成功率,当测量遮挡时长比为0.4时,改进型开关约束算法将原开关约束算法对野值点的预测成功率由89.35%提高到了97.4%;与原开关约束算法相比,引入权值判断法的改进型开关约束算法剔除了同用户多边框的异常拓扑测量值,减小了计算开销,提高了合作定位精度和鲁棒性。

关键词：相机拓扑测量惯性导航系统因子图合作定位鲁棒性

Combined BDS and GPS Adaptive Vector Tracking Loop in Challenge Environment

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Combined BDS and GPS Adaptive Vector Tracking Loop in Challe...

A Low Complexity Gaussian Parametric Message Passing based Cooperative Localization Algorithm

第七届中国卫星导航学术年会

作者： Yulong Song baowang lian School of Electronics and Information Northwestern Polytechnical University

ISBN: (纸本)9789811009334

Satellite navigation receiver would have difficulties in continuous positioning or get a bad positioning performance in dense urban environment, mostly due to low signal-to-noise ratio and frequently signal outage. To improve robustness under the challenge environment, a combined BDS（Bei Dou Satellites System） and GPS（Global Positioning System） adaptive vector tracking loop is proposed. An adaptive EKF（Extended Kalman Filter） base on innovation sequences is employed to tune the tracking loop, and generate navigation solutions. The algorithms are implemented on Matlab software receiver and digital IF（Intermediate Frequency） signals grabbed by a GNSS（Global Navigation Satellite System） signal sampler under blocked outdoor scenarios are utilized to verify the performance. The tracking and positioning results of vector and scalar tracking loop are compared.

关键词： Challenge Environment BDS GPS Adaptive Vector Tracking Loop EKF

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A Low Complexity Gaussian Parametric Message Passing based C...

基于自适应抗野值Kalman滤波技术的卫星导航接收机授时方法

第九届中国卫星导航学术年会

作者： Yangyang Liu baowang lian School of Electronics and Information Northwestern Polytechnical University

Based on the theory of factor graph and belief propagation,a low complexity cooperative localization algorithm with Gaussian parametric message passing is proposed to improve the performance where the non-cooperative localization methods failed due to the insufficient coverage of *** system model is established according to the Bayesian *** samples are used to represent the salient characteristics of the local message,and a Gaussian parametric message passing rule is designed to reduce the burden of the network *** constructing a relative spatial relationship between the target and its neighbour nodes,a novel message initialization method is put forward to concentrate the samples where the messages have significant *** order to facilitate efficient computation of peer-to-peer messages,the nonlinear observation equation is linearized approximately by exploiting the Taylor *** the expression of the message updating is deduced and the detailed flow of the algorithm is *** results show that the proposed algorithm leads to an excellent performance at the communication overhead and computational complexity,with losing negligible localization accuracy.

关键词： Cooperative localization Belief propagation(BP) Wireless sensor networks Gaussian parametric

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西北工业大学学报 2014年第3期32卷 378-381页

作者：何伟廉保旺杨琼西北工业大学大学电子信息学院陕西西安710072

在高动态与强干扰条件下,卫星导航接收机码跟踪环路与载波跟踪环路会出现异常抖动进而影响卫星导航接收机的授时精度,针对这一问题提出了一种新的基于抗野值Kalman滤波技术的卫星导航接收机授时方法。该方法可以有效消除码环与载波环的... 详细信息

在高动态与强干扰条件下,卫星导航接收机码跟踪环路与载波跟踪环路会出现异常抖动进而影响卫星导航接收机的授时精度,针对这一问题提出了一种新的基于抗野值Kalman滤波技术的卫星导航接收机授时方法。该方法可以有效消除码环与载波环的异常抖动对解算出的卫星钟差的影响,并且对连续出现的野值也有很好的剔除效果。同时该授时方法还可以有效地对卫星导航接收机的晶振频率误差进行估计,进而对1PPS(pulse per second)信号发生器的频率控制字进行调整,提高系统的授时精度。经过实验验证,该授时方法可以有效提高卫星导航接收机的授时精度以及授时系统的鲁棒性。

关键词：适应Kalman滤波抗野值卫星导航高精度授时