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Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG xiaofeng.tao Shujun HAN Huici WU Kai YANG Zhu HAN National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SATech-01 satellite

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Science China Technological Sciences 2025年

作者： Hongbo XUE Wei SONG Haoran ZHAO Yiteng ZHANG Shanzhi YE Jindong WANG Ran tao Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang XUE Yingying TANG Liu LIU Jinsong LI Xiaocheng ZHU Baoquan LI Jinguo LIU Wen CHEN xiaofeng ZHANG Yonghe ZHANG Lei LI State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Solar Activity and Space Weather National Space Science Center Chinese Academy of Sciences Key Laboratory of Electronics and Information Technology for Space Systems National Space Science Center Chinese Academy of Sciences State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Innovation Academy for Microsatellites Chinese Academy of Sciences

On July 27, 2022, a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer（referred to as the CPT system） was launched onboard the Space Advanced Technology demonstration satellite（SATech-01） by a ZK-1A rocket. The payload comprises a scalar coherent population trapping magnetometer（CPTM）, triaxial anisotropic magnetoresistance magnetometer（AMRM）, and nano star tracker mounted on a non-magnetic telescopic tubular mast. This configuration enables synchronized measurement of scalar and vector geomagnetic fields, as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite platforms. On November 7, 2022,the novel telescopic tubular mast was deployed in orbit, extending to a length of 5.28 m. The CPTM, an absolute scalar magnetometer with an omnidirectional sensor, is the first China-developed quantum/atomic magnetometer successfully operating in space. In orbit, the CPTM has sensitivity of ～10 pT/Hz1/2and can automatically operate under complex magnetic field variations. The difference between the scalar fields obtained using the CPTM and CHAOS model has a mean deviation of–3.73 n T and a standard deviation of 26.11 nT（1σ）, without on-orbit calibration or correction. The miniaturized AMRM has a sensitivity of ～0.3 n T/Hz1/2and maintains stable and reliable operation in orbit. The low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″（1σ） in orbit. The mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system's performance,automation level, and reliability.

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Characteristics and generations of internal wave in the Sulu Sea inferred from optical satellite images

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Journal of Oceanology and Limnology 2020年第5期38卷 1435-1444页

作者： ZHANG Xudong LI xiaofeng ZHANG tao CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Center for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China College of Geomatics Shandong University of Science and TechnologyQingdao 266071China

Characteristics and generation of internal waves(IWs)in the Sulu Sea are studied using Moderate-Resolution Imaging Spectroradiometer(MODIS)and Visible Infrared Imaging Radiometer Suite(VIIRS)images taken from October 2016 to September *** observations show that IWs in the Sulu Sea mainly located in the shallower western areas with occasional observations in the deeper eastern *** dominant length of wave crest(LWC)of IWs is between 50 and 150 km with the largest LWC reaching over 300 *** analysis of temporal distributions of IWs shows that March has the most IWs and July has the *** analysis shows that the seasonal variation is mainly due to the cloud contamination of optical satellite *** generation sites of IWs are analyzed using satellite *** possible generation sites for IWs in the western Sulu Sea and one generation site for IWs in the eastern Sulu Sea are found using the ray-tracing *** IW sources in the same strait are found,which may be due to the seawater fl ow over the strait in diff erent *** analysis shows that IWs with long wave crest in the Sulu Sea is a combined eff ort of all straits between small islands in the Sulu *** generated IWs with long wave crest in the eastern Sulu Sea are studied,which are generated at the straits around(121.5°E,6°N)by the nonlinear evolution of internal tide originated from the Sulu Archipelago.

关键词： internal waves(IWs) Sulu Sea Moderate-Resolution Imaging Spectroradiometer(MODIS) Suomi National Polar-Orbiting Partnership(NPP)

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Differential game-based analysis of multi-attacker multi-defender interaction

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Science China(Information Sciences) 2021年第12期64卷 202-214页

作者： Qiuyue GAO Huici WU Yunfei ZHANG xiaofeng.tao National Engineering Laboratory for Mobile Network Technologies Beijing University of Posts and Telecommunications

Due to the increasing number of wireless terminals and progressively extensive interconnections among them, interaction between the attack group and defense group is becoming a dominant security manifestation in future wireless networks. This paper focuses on the modeling and analysis of multi-attacker to multi-defender interaction. First, considering the continuous interaction between the attack group and defense group in real-time, a differential game-based multi-attacker to multi-defender interaction model is explicated with paralysis threshold introduced to reduce the ping-pong effect in paralysis. Optimal control theory is then introduced to obtain the equilibrium strategy with Hamilton best control method and a proposed optimal strategy selection algorithm for multi-attacker to multi-defender interaction. Finally, simulations are provided to demonstrate the evolutionary trajectory of optimal attack and defensive strategies and the relationship between the paralysis threshold and the group strength evolution results. Numerical results show the attackers and defenders are aggressive to strengthen their groups initially and then gradually decrease their strength to obtain ideal cost-effectiveness ratios. Moreover, increasing the defense paralysis threshold within a certain range will be more conducive to improving the defense effectiveness.

关键词： differential game multi-attacker to multi-defender interaction optimal control theory Hamilton function equilibrium strategy

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Practical cloud storage auditing using serverless computing

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Science China(Information Sciences) 2024年第3期67卷 33-47页

作者： Fei CHEN Jianquan CAI tao XIANG xiaofeng LIAO College of Computer Science and Software Engineering Shenzhen University College of Computer Science Chongqing University

Cloud storage auditing research is dedicated to solving the data integrity problem of outsourced storage on the cloud. In recent years, researchers have proposed various cloud storage auditing schemes using different techniques. While these studies are elegant in theory, they assume an ideal cloud storage model;that is, they assume that the cloud provides the storage and compute interfaces as required by the proposed schemes. However, this does not hold for mainstream cloud storage systems because these systems only provide read and write interfaces but not the compute interface. To bridge this gap, this work proposes a serverless computing-based cloud storage auditing system for existing mainstream cloud object storage. The proposed system leverages existing cloud storage auditing schemes as a basic building block and makes two adaptations. One is that we use the read interface of cloud object storage to support block data requests in a traditional cloud storage auditing scheme. Another is that we employ the serverless computing paradigm to support block data computation as traditionally required. Leveraging the characteristics of serverless computing, the proposed system realizes economical, pay-as-you-go cloud storage auditing. The proposed system also supports mainstream cloud storage upper layer applications(e.g., file preview) by not modifying the data formats when embedding authentication tags for later auditing. We prototyped and open-sourced the proposed system to a mainstream cloud service, i.e., Tencent Cloud. Experimental results show that the proposed system is efficient and promising for practical use. For 40 GB of data, auditing takes approximately 98 s using serverless computation. The economic cost is 120.48 CNY per year, of which serverless computing only accounts for 46%. In contrast, no existing studies reported cloud storage auditing results for real-world cloud services.

关键词： cloud storage auditing serverless computing object storage usability

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Effects of Re on surface eutectic formation for Ni-base single crystal superalloys during directional solidification

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Journal of Materials Science & Technology 2017年第11期33卷 1308-1313页

作者： Liang Cao Yizhou Zhou tao Jin xiaofeng Sun Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Effects of Re on the formation of surface eutectics have been investigated by using Ni-base single crystal superalloys with different Re additions. It was found that Re promotes the segregation of Al and Ta to the eutectic melt, leading to an increase of the surface and internal eutectics. In addition, the addition of Re also increased the freezing range, the local solidification time, and the permeability of the dendritic network within the mushy zone. These factors ultimately promoted the outflow of the interdendritic residual liquid with the action of solidification shrinkage, and led to the formation of more surface eutectics. In contrast, the addition of Re had no obvious influence on the surface eutectic microstructures.

关键词： Surface eutectic Re addition Single crystal Superalloy

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Effect of vacuum impregnation on the performance of Co/SiO_2 Fischer-Tropsch catalyst

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Journal of Natural Gas Chemistry 2011年第4期20卷 350-355页

作者： xiaofeng Zhou Qingling Chen Yuewu tao Huixin Weng Research Center of Petroleum Processing East China University of Science and Technology Shanghai 200237 China Shanghai Research Institute of Petrochemical Technology SINOPEC Shanghai 201208 China

Two silica-supported cobalt catalysts were prepared by incipient wetness impregnation under atmospheric and vacuum conditions.N2 ph- ysisorption,H2 chemisorption,XRD,SEM,TEM,XPS and H2-TPR were used to characterize the *** results showed that the impregnation methods had an effect on the size,dispersion and reducibility of cobalt *** vacuum conditions,cobalt-containing steeping liquor could penetrate into the inner pores of silica support and more bivalent cobalt oxides were formed in the Co3O4 ***,cobalt precursors were rarely inclined to agglomerate and the smaller cobalt particles were uniform on the support,which led to the higher activity of the Co/SiO2（B）catalyst than the normal one under the reaction conditions of 483- 523 K,1 - 2 MPa,gas hourly space velocity of 500–1000 h-1 and molar ratio of H2/CO=0.5 - 2.0.

关键词： Fischer-Tropsch synthesis cobalt catalysts silica vacuum impregnation

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Resource Allocation for Two-Way Amplify and Forward OFDM Relay Networks

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China Communications 2017年第8期14卷 76-82页

作者： Zhijun Liu xiaofeng.tao Waheed ur Rehman Wireless Technology Innovation Institute Key Laboratory of Universal Wireless CommunicationsBeijing University of Posts and TelecommunicationsBeijingChina

Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power consumption while satisfy system throughput requirement is becoming a vital issue. In this paper, we investigate energy-efficiency resource allocation(RA) based on PNC with amplify-and-forward(AF) protocol in orthogonal frequency division multiple(OFDM) bidirectional transmission. To minimize the overall transmit power consumption with required system throughput requirement, we consider joint subcarriers and power allocation and formulate the objective task into a constrained optimization problem where the best relay node is selected to minimize total transmit power. The closed form optimization power allocation solutions are acquired by analytical derivation. Based on derivation, we propose a novel optimal energy-efficient power allocation(OE-PA). Numerical results are given to evaluate the performance of the derived scheme as compared to other schemes and show that our scheme has signifi cant improvement to energy saving.

关键词： Energy-effi ciency Resource allocation physical-layer network coding OFDM system

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Effect of C and Hf Contents on the Interface Reactions and Wettability between a Ni_3Al-Based Superalloy and Ceramic Mould Material

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Journal of Materials Science & Technology 2016年第2期32卷 177-181页

作者： Xiaoyan Chen Yizhou Zhou tao Jin xiaofeng Sun Institute of Metal Research Chinese Academy of Sciences

The influence of active elements C and Hf on the interface reactions and wettability between a Ni3Albased superalloy and the ceramic mould material was studied by using a sessile drop experiment, The microstructure of the alloy interface was investigated by scanning electron microscopy analysis and the phase identification was performed by X-ray diffraction analysis, The results show that interface reactions occur as C and Hf contents reach a critical value, The critical values for C and Hf to cause interface reactions are 0,12 wt% and 1,17 wt%, respectively, The reaction products contain HfO2 and 9Al2OH,Cr2O3, Adsorptions of Hf and interface reactions improve the wettability obviously,

关键词： Superalloys Ceramic Interface reaction Wettability C Hf

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Anti-Jamming and Anti-Eavesdropping in A2G Communication System with Jittering UAV

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China Communications 2023年第10期20卷 230-244页

作者： Huici Wu Yang Wen xiaofeng.tao Jin Xu National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and TelecommunicationsBeijing 100876China State Grid Hunan Electric Power Information and Communication Corporation Changsha 410118China

This paper focuses on anti-jamming and anti-eavesdropping problem in air-to-ground(A2G)communication networks considering the impact of body jitter of unmanned aerial vehicle(UAV).A full-duplex(FD)active ground eavesdropper launches jamming attack while eavesdropping to stimulate the legitimate transmitter(i.e.,UAV)to increase its transmission *** legitimate transmitter’s objective is to against the simultaneous wiretapping and jamming with a robust and power-efficient transmission *** active eavesdropper aims to minimize the system secrecy *** study the interaction between the legitimate transmitter and the active eavesdropper,a non-cooperative game framework is ***,considering the impact of UAV jitter on antenna array response and secrecy performance,we first investigate the UAV’s transmission power minimization problem for the worst scenario with minimum legitimate data rate and maximum eavesdropping data rate under UAV ***,the active eavesdropper’s secrecy rate minimization problem with the worst scenario is investigated by optimizing its jamming *** equilibrium is proved to be existed and obtained with the proposed iterative ***,extensive numerical results are provided to evaluate the system secrecy performance and to show the secrecy performance gains of the proposed method.

关键词： UAV jitter A2G communication active eavesdropper non-cooperative game

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