检索结果-南通市图书馆

Quality of service aware admission control in cognitive device-to-device network

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 22-29,36页

作者： FU Zi-xi HU Chun-jing PENG Tao LU Qian-xi WANG Wen-bo Wireless signal processing and Network lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

A hybrid system of cellular mode and device-to-device （D2D） mode is considered in this paper, where the cellular resource is reused by the D2D transmission. With the objective of capacity maximization, the power optimization of D2D sub-system is considered, taking into account quality of service （QoS） requirement. The power optimization problem is divided into two stages： The first stage is the admission control scheme design based on the QoS requirement of D2D users, and the second is power allocation to maximize aggregate throughput of admissible D2D users. For the D2D admission control problem, a heuristic sorting-based algorithm is proposed to index the admissible D2D links, where gain to Interference ratio （GIR） sorting criterion is used. Applying an approximate form of Shannon capacity, the power allocation problem can be solved by convex optimization and geometric programming tools efficiently. Based on the theoretical analysis, a practical algorithm is proposed. The precision can reach a trade-off between complexity and performance. Numerical simulation results confirm that combining with GIR sorting method, the proposed scheme can significantly improve the D2D system＇s capacity and fairness.

关键词： cognitive radio QoS power control geometric programming sorting-based algorithm

Cooperative HARQ protocol and diversity analysis of systems with multiple incremental relays

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 8-13页

作者： FAN Bin , WANG Wen-bo, LIN Yi-cheng, ZHENG Kan Wireless signal processing and Network lab. key lab.ratory of Universal Wireless Communication, Ministry of Education, Beijing University of Posts and Telecommunications, Beijing 100876, China Wireless signal processing and Network lab Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless networks contain an inherent distributed spatial diversity that can be exploited by relays. Relay networks can take advantage of the broadcast-oriented nature of wireless transmission, but require more radio resource to transmit data for their multi-hop traits. Fortunately, incremental relaying technique, which can choose direct or multi-hop transmission adaptively, can efficiently utilize resource. In this article, the incremental transmission with amplify-and-forward （AF） relays is focused on. A practical hybrid-automatic retransmission request （HARQ） protocol is designed, and the related optimal relay selection strategy is proposed. To analyze the cooperative diversity of system with the proposed protocol, the capacity lower bound is deduced. Simulation and analytical results indicate that by adopting the optimal relay selection strategy, the system with the proposed HARQ protocol can achieve an order of cooperative diversity that equals the aggregated number of the relay and source nodes.

关键词： cooperative HARQ AF incremental relay diversity gain

Improving Integrality of Detected Moving Objects Based on Image Matting

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2014年第4期23卷 742-746页

作者： ZHANG Liang WANG Haili DENG Tao HE Xiaomei Tianjin key lab.for Advanced signal processing Civil Aviation University of China Training Center of Engineering Technology Civil Aviation University of China

The integrality of moving objects is the basis for video-based object tracking and action analysis. But it often becomes unreliable as a result of shadow elimination when the object has similar properties with real shadow. The proposed methods manage to improve the integrality of detected moving objects as much as possible, by image matting operated on candidate shadow regions. Existing approaches for image matting require manual lab.ling of foreground and background. Considering the moving feature points in shadow may cause classification errors, we propose automatic scribbling methods based on Scale invariant feature transform(SIFT) and Speeded-up robust feature(SURF) respectively. Experiments demonstrate that our methods eliminate real shadow effectively and improve object segmentation in the case of object parts and shadows presenting similar characteristics.

关键词： Moving object detection Object integrality Shadow elimination SURF matching Image matting

Solving multi-object radar cross section based on wide-angle parabolic equation method

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2006年第4期17卷 722-724页

作者： Huang Zhixiang Wu Qiong Wu Xianliang The key lab.of Ministry of Education of Intelligent Computing & signal processing Anhui Univ. Hefei 230039 P. R. China

Based on a Pade approximation, a wide-angle parabolic equation method is introduced for computing the multiobject radar cross section （RCS） for the first time. The method is a paraxial version of the scalar wave equation, which solves the field by marching them along the paraxial direction. Numerical results show that a single wide-angle parabofic equation run can compute multi-object RCS efficiently for angles up to 45 ° . The method provides anew and efficient numerical method for computation electromagnetics.

关键词： parabolic equation method Pade approximation radar cross section paraxial direction.

Multidimensional reconciliation protocol for continuous-variable quantum key agreement with polar coding

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2018年第9期61卷 99-102页

作者： ShengMei Zhao ZhiGang Shen Hong Xiao Le Wang Institute of signal processing Transmission Nanjing University of Posts and Telecommunications key lab.of Broadband Wireless Communication and Sensor Network Technology Ministry of Education

Continuous-variable quantum key distribution（CVQKD）[1-7]allows two remote parties（Alice and Bob）to share a secret key,even in the presence of an eavesdropper（Eve）with unlimited computational power[8-17].While,a highly efficient reconciliation protocol[18-21]is crucial in a CVQKDsystem, which can not only extract the errorless secret keys, but also provide a promising way to achieve a long distance CVQKD at a low signal-to-noise ratio （SNR）.

关键词：和解协议连续变量钥匙多维编码 SNR 长距离

Autofocus by Lissajous scanning in time reversal optical scanning holography

在线全文

学校读者我要写书评

暂无评论

CHINESE OPTICS LETTERS 2024年第8期22卷 080501-080501页

作者： Liu, Jie Ou, Haiyan Wang, Hua Peng, Lin Shao, Wei Univ Elect Sci & Technol China Shenzhen Inst Adv Study Shenzhen 518000 Peoples R China Univ Elect Sci & Technol China Sch Phys Chengdu 611731 Peoples R China Guilin Univ Elect Technol Key Lab Cognit Radio & Informat Proc Guilin 541004 Peoples R China

In this Letter, an autofocusing method in optical scanning holography (OSH) system is proposed. By introducing Lissajous scanning into multiple signal classification (MUSIC) method in time-reversal (TR) OSH, the axial locations of the targets can be retrieved with better resolution and the peak prominence increases from 0.21 to 0.34. The feasibility of this method is confirmed by simulation as well as experiment.

关键词： digital holography Lissajous scanning image reconstruction axial localization SECTIONAL IMAGE-RECONSTRUCTION SCATTERING MICROSCOPY TARGETS

Power minimization with derivative constraints for high dynamic GPS interference suppression

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2012年第4期55卷 857-866页

作者： WU RenBiao 1,2,LI Chan 1 & LU Dan 1 1 Tianjin key lab.ratory for Advanced signal processing,Civil Aviation University of China,Tianjin 300300,China 2 Intelligent Information Institute of ATR lab.Shenzhen University,Shenzhen,518060,China Tianjin key lab.ratory for Advanced signal processing Civil Aviation University of China Intelligent Information Institute of ATR lab Shenzhen University

In this paper,a novel adaptive interference suppression algorithm is proposed for high dynamic GPS (global positioning system) *** new method incorporates derivative constraints on the inter-ference DOA (direction of arrival) into power minimization approach,which could broaden the width of nulls in the interferences directions and adapt to the rapid change of the interference *** with the traditional wide nulling algorithm based on the derivative constraints,the new method does not have to know or estimate the DOAs of the desired signal and the *** new method is firstly discussed in the context of spatial processing,and then extended to space-time adaptive processing to mitigate wideband diffusive multipath *** of the new method is verified via simulation examples.

关键词： GPS interference cancellation adaptive arrays space-time adaptive processing high dynamic GPS receiver

A novel STAP method for the detection of fast air moving targets from high speed platform

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2012年第6期55卷 1259-1269页

作者： WU RenBiao 1,2,JIA QiongQiong 1 & LI Hai 1 1 Tianjin key lab.ratory for Advanced signal processing,Civil Aviation University of China,Tianjin 300300,China 2 Intelligent Information Institute of ATR lab.Shenzhen University,Shenzhen 518060,China Tianjin key lab.ratory for Advanced signal processing Civil Aviation University of China Intelligent Information Institute of ATR lab Shenzhen University

Space-time adaptive processing (STAP) is an effective method for detecting moving target in airborne/spaceborne ***,the detection of fast air moving targets from high speed platform is challenged by the range walk of both the clutter and moving *** is well known that keystone formatting can be used to compensate for the range walk of multiple moving targets simultaneously without using the knowledge of the motion ***,in the presence of serious Doppler ambiguity of fast air moving targets,distribution of the clutter will be affected by the keystone formatting matched to the ambiguity number of targets,and as a result the STAP performance will *** this paper,a novel STAP method is proposed for the detection of fast air moving targets from high speed platform,which can deal with the range walk of both clutter and *** of the new method is verified via simulation examples.

关键词： airborne/spaceborne radar keystone formatting space-time adaptive processing (STAP) moving target detection

A novel strategy for fine-grained semantic verification of civil aviation radiotelephony read-backs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2022年第12期35卷 266-277页

作者： Guimin JIA Junxian LI Tianjin key lab.for Advanced signal processing Civil Aviation University of ChinaTianjin 300300China College of Electronic Information and Automation Civil Aviation University of ChinaTianjin 300300China

During the flight of the aircraft,the pilot must repeat the instruction sent by the controller,and the controller must further confirm these read-backs,in this way to further ensure the safety of air ***,fatigue,tension,negligence and other human factors may prevent the controller from realizing read-back errors in time,which is a huge hidden danger for the safety of civil aviation *** paper proposes a novel strategy to implement fine-grained semantic verification of radiotelephony read-backs by introducing interaction layer and attention mechanism at the output of BiLSTM *** with the traditional twochannel verification strategy,the interaction layer is added to obtain fine-grained semantic matching relation representation,rather than connecting the BiLSTM output vectors to obtain the overall semantic representation of the *** by adding attention layer,the new strategy can capture the potential semantic relation between the read-backs and the instructions,which is applicable to non-standard diction and abbreviated read-backs in real radiotelephony *** experiments are conducted and the results show that the proposed new strategy is more effective than the traditional method for read-backs checking,and the average test accuracy of the new strategy based on the Chinese ATC radiotelephony read-backs corpus can reach 93.03%.

关键词： Attention mechanism BiLSTM Interaction layer Radiotelephony read-backs Semantic verification