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Optimization-based mode selection scheme for OAM millimeter wave system in the off-axis misalignment case

Digital communications and networks 2024年第1期10卷 101-108页

作者： Haie Dou Lei Wang Bin Kang Baoyu Zheng Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing210003China School of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing210003China

Millimeter-wave transmission combined with Orbital Angular Momentum(OAM)has the advantage of reducing the loss of beam power and increasing the system ***,to fulfill this advantage,the antennas at the transmitter and receiver must be parallel and coaxial;otherwise,the accuracy of mode detection at the receiver can be seriously *** this paper,we design an OAM millimeter-wave communication system for overcoming the above ***,the first contribution is that the power distribution between different OAM modes and the capacity of the system with different mode sets are analytically derived for performance *** second contribution lies in that a novel mode selection scheme is proposed to reduce the total interference between different *** results show that system performance is less affected by the offset when the mode set with smaller modes or larger intervals is selected.

关键词： Orbital angular momentum Millimeter wave Off-axis misalignment Mode selection Capacity

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Modeling and analysis of anti-worm in P2P networks

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 112-118页

作者： TANG Xin WANG Ru-chuan SHAO Xing College of computer Nanjing University of Posts and Telecommunications Nanjing 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology N anjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China

Anti-worm is an effective way to fight against malicious worm and has been followed closely by malicious worm researchers recently. However, active and passive confronting technologies in peer-to-peer （P2P） networks have not been studied in depth. This paper introduces both of them to fight against malicious worm in P2P networks. To study their effectiveness in P2P networks, this paper takes the topology degree in P2P networks into consideration and puts forward a four-state propagation model for active anti-worm and a five-state propagation model for passive anti-worm respectively. Both of the models are simplified in the case that size of a P2P network is large enough. The simulation results have not only validated the effectiveness of our propagation models but also evaluated the excellent performance of both active anti-worm and passive anti-worm.

关键词： P2P network anti-worm worm propagation model

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Geometry Based LM of Robot to Imitate Human Motion with Kinect 4

Geometry Based LM of Robot to Imitate Human Motion with Kine...

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4th IEEE International Conference on Image, Vision and Computing, ICIVC 2019

作者： Guo, Wei Chen, Jianxin Zhang, Ming Pan, Zhaolai Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing210003 China

ISBN: (纸本)9781728123257

Humanoid robots are easily accepted by people because they have a body shape and appearance close to human. Humanoid robots have many application scenarios and great application potentials. Nevertheless, it is not easy to realize robot simulation due to the different physical structures of human bodies and robots. In this paper, we propose a geometry based LM algorithm for the robot to imitate the human motion of upper limb in real time. This method greatly improves the joint angle similarity under the premise of ensuring the similarity of the end trajectories. We designed a comprehensive and unrestricted motion simulation experiment to verify this method. © 2019 IEEE.

关键词： Inverse kinematics

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network traffic application type identification based on gravitational clustering

Network traffic application type identification based on gra...

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2013 International Conference on Management Innovation and Information technology, MIIT 2013

作者： Zhang, Dengyin Li, Xiuyun Liao, Jianfei Wang, Mingxiang Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications China

ISBN: (纸本)9781845649401

The application identification, which aims at classifying traffic accurately, is the basic of the analysis network traffic. Various improved clustering methods which based on k-means are widely used in the application identification of the network traffic. However, these algorithms are highly complex, and difficult to meet the real-time and high accuracy of the application requirements in traffic identification. By taking the k-means as the prototype and merging distance and density together, this paper proposes a gravitational clustering method to identify network traffic type which has resolved the localized solutions problem of the original clustering algorithm. The experiment result and analysis show that, traffic identification method based on this paper has higher recognition rate, faster convergence, and better clustering effect. © 2014 WIT Press.

关键词： Clustering algorithms

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A RGB-D face recognition approach without confronting the camera

A RGB-D face recognition approach without confronting the ca...

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IEEE International Conference on Computer and communications, ICCC 2015

作者： Zhou, Wei Chen, Jian-Xin Wang, Lei Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing210003 China

ISBN: (纸本)9781467381253

Face recognition research mainly focuses on traditional 2D color images, which is extremely susceptible to be affected by external factors such as various viewpoints and has limited recognition accuracy. In order to achieve improved recognition performance, as well as the 3D face holds more abundant information than 2D, we present a 3D human face recognition algorithm using the Microsoft's Kinect. The proposed approach integrates the depth data with the RGB data to generate 3D face raw data and then extracts feature points, identifies the target via a two-level cascade classifier. Also, we build a 3D-face database including 16 individuals captured exclusively using Kinect. The experimental results indicate that the introduced algorithm can not only achieve better recognition accuracy in comparison to existing 2D and 3D face recognition algorithms when the probe face is exactly in front of Kinect sensor, but also can increase 9.3% of recognition accuracy compared to the PCA-3D algorithm when it is not confronting the camera. © 2015 IEEE.

关键词： Face recognition

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Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter communication System

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China communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang Ting Li Yin Lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

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Modulating the Lasing Performance of the Quantum Dot-Cavity System by Adding a Resonant Driving Field

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Chinese Physics Letters 2017年第1期34卷 115-119页

作者：秦利国王琴 Institute of Signal Processing and Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003 Key Lab of Broadband Wireless Communication and Sensor Network Technology(Ministry of Education) Nanjing University of Posts and TelecommunicationsNanjing 210003

We propose a new scheme on modulating the lasing performance of a quantum dot-cavity system. Compared to the conventional above-band pump, in our new scheme an additional resonant driving field is applied on the quantum dot-cavity system. By employing the master equation theory and the Jaynes-Cummings model, we are able to study the interesting phenomenon of the coupling system. To compare the different behaviors between using our new scheme and the conventional method,we carry out investigatioin for both the 'good system'and 'more realistic system', characterizing several important parameters, such as the cavity population, exciton population and the second-order correlation function at zero time delay. Through numerical simulations,we demonstrate that for both the good system and more realistic system, their lasing regimes can be displaced into other regimes in the presence of a resonant driving field.

关键词： Modulating the Lasing Performance of the Quantum Dot-Cavity System by Adding a Resonant Driving Field

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BIPR: A new TCP variant over satellite networks

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Journal of China Universities of Posts and Telecommunications 2011年第SUPPL. 1期18卷 34-39页

作者： Xiao, Fu Sun, Li-Juan Wang, Ru-Chuan Fang, Yue-Chao College of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China

Standard TCP perform poorly in satellite networks since the long delay, high bit error ratio and other characters. A new TCP variant, called BIPR for satellite networks is presented in this paper. Using the binary increase of window growth function, long bandwidth-delay product can be overcome, while probe method is also adopted in BIPR for conquer the high bit error rates in satellite links. Simulation results show that good performances in terms of throughput, link utilization and RTT fairness can be achieved in satellite networks using our method. © 2011 The Journal of China Universities of Posts and Telecommunications.

关键词： Satellites

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JOINT LLR-CRC ERROR MITIGATION FOR TWO-WAY ADAPTIVE DENOISE-AND-FORWARD network CODING

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Journal of Electronics(China) 2013年第4期30卷 352-361页

作者： Cheng Yulun Yang Longxiang Jiangsu Key Lab of Wireless Communications Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications

network Coding (NC) brings correlation between the coded signals from different sources, which makes the system more vulnerable to the decode error at relay. Conventional Cyclic Redundancy Code (CRC) has been implemented for error bit detection. However, its error correction is simply ignored. To fully exploit this feature, this paper proposes a novel joint Log-Likelihood Ratio (LLR) CRC error mitigation for NC two way relay channel. Specific thresholds are designed to estimate the error number of data block and identify those which can be recovered if the number is within the error correction scope of CRC. We examine two modes of the thresholds, one based on the average Bit Error Rate (BER) of source-relay link, while the other based on that of instantaneous one. We provide the full analysis for the Pair-wise Error Probability (PEP) performance of the scheme. A variety of numerical results are presented to reveal the superiority of the proposed scheme to conventional CRC NC under independent Rayleigh fading channels. Moreover, the efficiencies of the proposed thresholds are also validated.

关键词： network Coding （NC） Log-Likelihood Ratio （LLR） Cyclic Redundancy Code （CRC） Denoise-and-forward Pair-wise Error Probability （PEP）

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Arbitrary-Oriented Ship Detection Based on Rotation Region Locating networks in Large Scale Remote Sensing Images 4

Arbitrary-Oriented Ship Detection Based on Rotation Region L...

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4th IEEE International Conference on Image, Vision and Computing, ICIVC 2019

作者： Liu, Xipeng Chen, Jianxin Kang, Bin Zhang, Xuguang Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing China

ISBN: (纸本)9781728123257

Although deep learning has dominated the ship detection domain, it still has two challenges: arbitrary-oriented densely arranged ships cause detection omissions and large scale image contains redundant areas. This paper proposes an effective convolutional neural network framework for arbitrary-oriented ship detection in large scale and complex scenes. In this framework, we propose Cumulative Feature Pyramid networks for multi-receptive-field feature fusion, which enhances high-level semantic information at all scales. Based on the outputs of Region Proposal networks, Rotation Region Locating network predicts rotation bounding box of arbitrary-oriented ships and adopts rotation intersection over union to avoid the effect of ship dense arrangement. For large scale scenes, No-Ship Area Suppression uses OTSU algorithm to generate binary mask and then filter out non-ship regions to reduce redundant computations. Additionally, we firstly build a remote sensing image dataset for ship detection, which contains 4237 images and over 21200 ships. Experimental comparisons with the state-of-the-art approaches validate the effectiveness, accuracy and robustness of the proposed method. © 2019 IEEE.

关键词： Ships

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