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基于二维异步同相正交直方图的调制方式识别

西安电子科技大学学报 2024年第4期51卷 78-90页

作者：万鹏武惠茜陈东瑞吴波西安邮电大学通信与信息工程学院陕西西安710121 陕西山利科技发展有限责任公司陕西西安710075

自动调制识别技术能够准确识别信号的调制类型,是信号处理领域中的一项关键技术。传统的识别方法在低信噪比下存在着识别准确率低的问题,并且当信号频率不稳定,或存在异步采样时,常规的识别方法性能将会出现恶化甚至失效。基于此,在信... 详细信息

自动调制识别技术能够准确识别信号的调制类型,是信号处理领域中的一项关键技术。传统的识别方法在低信噪比下存在着识别准确率低的问题,并且当信号频率不稳定,或存在异步采样时,常规的识别方法性能将会出现恶化甚至失效。基于此,在信噪比和延迟变化的信道条件下,针对低速异步采样信号,研究基于深度学习的调制方式识别技术。首先对低速异步采样信号进行建模,利用其同相正交分量生成二维异步同相正交直方图,然后通过径向基函数神经网络提取该二维图像的特征参数,完成对输入信号的调制方式识别,最后经过大量的计算机仿真验证了该方法对7种调制方式的识别准确率。实验结果表明,在受到加性高斯白噪声的信道模型下,在低速异步采样的输入信号信噪比为6 dB时,可达到约95%以上的平均识别准确率,并通过对比实验验证了所提方案的有效性和鲁棒性。

关键词：调制方式识别二维异步同相正交直方图深度学习径向基神经网络

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混合信道下基于到达时间的快速直接定位算法

西安邮电大学学报 2024年第2期29卷 20-26页

作者：万鹏武李文杰彭康西安邮电大学通信与信息工程学院陕西西安710121 陕西省信息通信网络及安全重点实验室陕西西安710121

为了实现复杂环境下视距(Line-of-Sigh,LOS)与非视距(Non-Line-of-Sigh,NLOS)同时存在的混合信道中的目标辐射源直接定位(Direct Position Determination,DPD),提出基于到达时间(Time-of-Arrival,TOA)的快速直接定位算法。该算法充分挖掘不同信道信号中的信息参数,采用最小二乘法原理构建代价函数,无需估计定位参数,避免了传统两步定位法所需的NLOS识别与数据关联。引入粒子群(Particle Swarm Optimization,PSO)算法精确估计目标辐射源的位置信息,以降低计算复杂度。将所提定位算法与基于TOA的两步定位法在定位精度方面进行对比,仿真结果表明,所提算法定位精度高于两步定位法,且可以逼近克拉美罗下界(Cramer-Rao Lower Bound,CRLB),能够快速定位混合信道中的目标辐射源。

关键词：混合信道目标辐射源直接定位最小二乘法粒子群算法克拉美罗下界

How to Select the Best Sensors for TDOA and TDOA/AOA Localization?

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China Communications 2019年第2期16卷 134-145页

作者： Yue Zhao Zan Li Benjian Hao pengwu wan Linlin wang State Key Laboratory of Integrated Service Networks Xidian University Collaborative Innovation Center of Information Sensing and Understanding

This paper focuses on the sensor subset optimization problem in time difference of arrival(TDOA) passive localization scenario. We seek for the best sensor combination by formulating a non-convex optimization problem, which is to minimize the trace of covariance matrix of localization error under the condition that the number of selected sensors is given. The accuracy metric is described by the localization error covariance matrix of classical closed-form solution, which is introduced to convert the TDOA nonlinear equations into pseudo linear equations. The non-convex optimization problem is relaxed to a standard semi-definite program(SDP) and efficiently solved in a short time. In addition, we extend the sensor selection method to a mixed TDOA and angle of arrival(AOA) localization scenario with the presence of sensor position errors. Simulation results validate that the performance of the proposed sensor selection method is very close to the exhaustive search method.

关键词： sensor selection localization TDOA/AOA non-convex convex relaxation

Passive Localization of Signal Source Based on UAVs in Complex Environment

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China Communications 2020年第2期17卷 107-116页

作者： pengwu wan Qiongdan Huang Guangyue Lu Jin wang Qianli Yan Yufei Chen XI’AN University of Posts and Telecommunications

For the influence caused by multipath fading and non-line-of-sight(NLOS)transmission,it is challenging to accurately localize a moving signal source in complex environment by using the wireless sensor network(WSN)on the *** this paper,we establish a special WSN in the sky to address this challenge,where each sensor is loaded on an unmanned aerial vehicle(UAV)and the operation center of all the UAVs is fixed on the *** on the analyzing of the optimal distribution and the position error calibration of all the sensors,we formulate the localization scheme to estimate the position of the target source,which combines the time difference of arrival(TDOA)method and the frequency difference of arrival(FDOA)*** by employing the semidefinite programming approach,we accurately obtain the position and velocity of the signal *** the simulation,the validity of the proposed method is verified through the performance comparison.

关键词： passive localization time difference of arrival wireless sensor network unmanned aerial vehicle semidefinite programming

New insights into the DPR mechanism of elastic energy released by polymer gel for enhanced oil recovery

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Petroleum 2024年第3期10卷 539-547页

作者： Hu Jia Junyi Wu Shaowei Wu Yanbin Liang Minghao wang Xiaojin wan pengwu Li State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduChina CNOOC Zhanjiang Branch ZhanjiangChina Oil Production Technology Institute of PetroChina Dagang Oilfield Company TianjinChina

Polymer gel was widely used as water shutoff agent in mature oil *** the results of single-phase plugging experiments show that the plugging rate of the polymer gel to the oil phase is lower than that of the water ***,the disproportionate permeability reduction(DPR)mechanism of polymer gels still remains *** this paper,we used four gel formulations including polyethyleneimine(PEI)and phenol-formaldehyde crosslinked gel with and without adding laponite to investigate the effect of gel elastic property on the water shutoff *** result of sand pack flooding experiments shown that the gel with higher elastic modulus has better effects on decreasing water cut and increasing oil *** adding laponite,the elastic modulus of phenol-formaldehyde crosslinked gel increased from 64.2 Pa to 192 Pa,and the elastic modulus of PEI crosslinked gel increased from 27.4 Pa to 36.5 *** to the phenol-formaldehyde-HAPM gel,the oil recovery of laponite-phenol-formaldehyde-HPAM gel increased by 5.2%and the maximum water cut decreased by 8.3%.Besides,comparing with PEI-HPAM gel,the oil recovery of laponite-PEI-HPAM gel increased by 2.7%and the water cut dropped by 27.8%.In the meanwhile,the laponite-phenol-formaldehyde-HPAM gel with higher elastic modulus obviously swells in the formation water but almost remains constant in oil at 105℃.The mass of gel soaked in the formation water increased from 42 g to 96 g and the gel volume increased by 300%within 48 *** study improves the understanding of the DPR mechanism of polymer gel for water shutoff.

关键词： Gel elasticity Water shutoff DPR Laponite Oil recovery

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侦察雷达天线扫描周期对抗估计方法

西安电子科技大学学报 2018年第4期45卷 161-165,180页

作者：马骁张海林郝本建万鹏武西安电子科技大学通信工程学院陕西西安710071

针对传统侦察雷达天线扫描周期估计方法精度不足的问题,提出一种基于单架旋翼无人机对多普勒雷达天线扫描周期精确估计的新方法.通过对无人机所接收雷达脉冲信号的处理,采用范数逼近的方式,分别用拟合平均法和平均拟合法在接收端有效地... 详细信息

针对传统侦察雷达天线扫描周期估计方法精度不足的问题,提出一种基于单架旋翼无人机对多普勒雷达天线扫描周期精确估计的新方法.通过对无人机所接收雷达脉冲信号的处理,采用范数逼近的方式,分别用拟合平均法和平均拟合法在接收端有效地重构出雷达天线的主瓣波束方向图,并以此为基础精确估计目标雷达天线的扫描周期参数.仿真实验以实战雷达作为目标源,验证了所提方法的有效性和鲁棒性.结果表明,当接收信噪比较高时,平均拟合法可更好地接近甚至达到克拉美罗下界性能.

关键词：侦察雷达扫描周期无人机主瓣波束方向图

Preface for the Special Issue on“Safety and Intelligent Maintenance of Offshore Structures”

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China Ocean Engineering 2024年第2期38卷 181-182页

作者： XU wan-hai State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

The ocean serves as a vital carrier for human resource development and economic growth and contains rich mineral resources such as oil,natural gas,polymetallic nodules,cobalt-rich ferromanganese crusts,polymetallic sulfides,and rare earth ***,the ocean has wealthy reserves of wind,wave,tidal,and solar energy,making it an essential strategic space for sustainable future ***,offshore structures are complex.

关键词： ocean offshore tidal

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能时频域信息融合的信源被动定位

西安电子科技大学学报 2021年第6期48卷 105-114页

作者：万鹏武姚媛媛闫千里陈煜飞西安邮电大学陕西省信息通信网络及安全重点实验陕西西安710121

随着无线通信环境的日益复杂,仅靠单一域(如能域、时域、频域、空域等)信息的定位技术已难以满足高精度信源定位的需求。针对非视距环境下信源定位性能恶化问题,提出能时频三域信息融合的信源被动定位技术,采用非视距误差反馈迭代修正... 详细信息

随着无线通信环境的日益复杂,仅靠单一域(如能域、时域、频域、空域等)信息的定位技术已难以满足高精度信源定位的需求。针对非视距环境下信源定位性能恶化问题,提出能时频三域信息融合的信源被动定位技术,采用非视距误差反馈迭代修正的方法实现信源目标的高精度定位。在合理构建复杂环境下的信源定位场景中,深入分析能时频三域定位参数模型,将各域非视距误差视作待估计参数并融合多域信息构建联合定位方程,基于对三域联合最大似然方程的分析,在求解过程中采用非视距误差统计量替换,完成对的方程的合理简化。在求解过程中引入距离平方与加权最小二乘法将非凸问题进一步转化为广义信赖域子问题。在无需非视距参数先验信息的情况下,通过二分法即可同时得到信源位置和速度参数以及非视距误差的初始估计。为保证复杂环境下定位精度,运用迭代法将非视距偏差作为反馈以提高信源位置参数估计精度。通过计算机仿真验证了该算法的有效性和可靠性。

关键词：非视距多域信息融合到达时间差广义信赖域子问题

Light People:*** May Lau,newly elected US NAE member in Hong Kong,talks about future of photonics and women in science

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Light(Science & Applications) 2024年第4期13卷 602-608页

作者： Yating wan Chenzi Guo Electrical and Computer Engineering the ComputerElectrical and Mathematical Sciences and Engineering DivisionKing Abdullah University of Science and Technology23955-6900 ThuwalSaudi Arabia Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina

Editorial Photonics technology remains a driving force in today’s scientific landscape,marked by continuous innovation and crossdisciplinary *** an enlighting conversation with Light:Science&Applications,*** May Lau,a pioneer in photonics research,shares her deep insights on the evolution of technologies of LEDs,lasers,challenges of hetero-epitaxy,and the future of micro-LEDs and quantum dot *** honored as a member of the US National Academy of Engineering(NAE)for her significant contributions to photonics and electronics using III-V semiconductors on silicon,*** stands out as the sole Hong Kong scholar inducted into the NAE this year,joining 114 new and 21 international *** this exclusive Light People interview,*** shares her journey as a pioneering woman in engineering,her commitment to mentorship and academia,and her perspective on advancing female representation in *** summary provided is distilled from ***’s thoughtful responses during the *** a deeper exploration of ***’s experiences and advice,the full interview is available in the Supplementary material.

关键词： interview lighting driving