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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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Impact of Maximum Transmit Power Limit on the First-Order and Second-Order Performance of Cognitive Opportunistic Relaying

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China communications 2015年第5期12卷 75-85页

作者： JIA Xiangdong DENG Pengfei ZHOU Ming YANG Longxiang ZHU Hongbo College of Computer Science and Engineering Northwest Normal University Wireless Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications Key Lab of Broadband wireless Communication and Sensor Network Technique of Ministry of Education Nanjing University of Posts and Telecommunications

Abstract： This paper focuses on the first-or- der and second-order performance of dual-hop underlay cognitive radio systems with oppor- tunistic relaying （UCR-OR） over indepen- dent and non-identically distributed （***.d） Rayleigh fading channels. For the UCR-OR systems, the tolerable maximum interference power （TMIP） Q at primary users （PUs） and the allowable maximum transmission power limit （AMTP） P at secondary users （SUs） are considered, simultaneously. We first obtain the closed-form solutions to the first-order performance such as outage probability, ave- rage symbol error ratio （SER）, and ergodic capacity （EC）. Secondly, we investigate the second-order statistical performance, i.e., ave- rage outage rate （AOR） and average outage duration （AOD）. With the consideration that in practice implementation the receiver perfor- mance is primarily influenced by the signal- to-noise ratio （SNR）（not the signal envelope）, the second-order statistical performance is investigated based on the equivalent instan- taneous end-to-end SNR. Finally, we present the detailed performance comparison analysis of UCR-OR systems by defining a random variable ,μ=Pmax/Q. The results show that the effect of μ on the first-order and second-or- der performances is different greatly. For the first-order performance, the perlbrmance gap is negligible when the value of// is relatively large. However, for the second-order one, the gap is distinct.

关键词： cognitive radio opportunistic relaying outage probability average outage rate average outage duration

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Improved side information generation algorithm for Wyner-Ziv video coding

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The Journal of China Universities of Posts and Telecommunications 2014年第1期21卷 109-115页

作者： ZHANG Deng-yin WU Yuan-yuan WAN Ming-xiang Sci-Tech Park of Internet of Things Nanjing University of Posts and Telecommunication Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunication

Side information has a significant influence on the rate-distortion（RD） performance of distributed video coding（DVC）. In the conventional motion compensated frame interpolation scheme, all blocks adopt the same side-information generation method regardless of the motion intensity inequality at different regions. In this paper, an improved method is proposed. The image blocks are classified into two modes, fast motion and slow motion, by simply computing the discrete cosine transformation（DCT） coefficients at the encoder. On the decoder, it chooses the direct interpolation and refined motion compensated interpolation correspondingly to generate side information. Experimental results show that the proposed method, without increasing the encoder complexity, can increase the average peak signal-to-noise ratio（PSNR） by up to 1~ 2 dB compared with the existing algorithm. Meanwhile, the proposed algorithm significantly improves the subjective quality of the side information.

关键词： DVC side information motion estimation motion compensation

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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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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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Phase-matching quantum key distribution with light source monitoring

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Chinese Physics B 2022年第5期31卷 165-172页

作者： Wen-Ting Li Le Wang Wei Li Sheng-Mei Zhao Institute of Signal Processing Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing 210003China

The transmission loss of photons during quantum key distribution(QKD)process leads to the linear key rate bound for practical QKD systems without quantum *** matching quantum key distribution(PM-QKD)protocol,an novel QKD protocol,can overcome the constraint with a measurement-device-independent structure,while it still requires the light source to be *** assumption is not guaranteed in practice,leading to practical secure *** this paper,we propose a modified PM-QKD protocol with a light source monitoring,named PM-QKD-LSM protocol,which can guarantee the security of the system under the non-ideal source *** results show that our proposed protocol performs almost the same as the ideal PM-QKD protocol even considering the imperfect factors in practical ***-LSM protocol has a better performance with source fluctuation,and it is robust in symmetric or asymmetric cases.

关键词： phase-matching quantum key distribution source fluctuation light source monitoring

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Single-qubit quantum classifier based on gradient-free optimization algorithm

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Chinese Physics B 2023年第10期32卷 241-247页

作者：张安琪王可伦吴逸华赵生妹 Institute of Signal Processing and Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing 210003China

A single-qubit quantum classifier(SQC)based on a gradient-free optimization(GFO)algorithm,named the GFO-based SQC,is proposed to overcome the effects of barren plateaus caused by quantum ***,a rotation gate R_(X)(φ)is applied on the single-qubit binary quantum classifier,and the training data and parameters are loaded intoφin the form of vector *** cost function is decreased by finding the value of each parameter that yields the minimum expectation value of measuring the quantum *** algorithm is performed iteratively for all parameters one by one until the cost function satisfies the stop *** proposed GFO-based SQC is demonstrated for classification tasks in Iris and MNIST datasets and compared with the Adam-based SQC and the quantum support vector machine(QSVM).Furthermore,the performance of the GFO-based SQC is discussed when the rotation gate in the quantum device is under different types of *** simulation results show that the GFO-based SQC can reach a high accuracy in reduced ***,the proposed GFO algorithm can quickly complete the training process of the ***,the GFO-based SQC has a good performance in noisy environments.

关键词： single-qubit quantum classifier gradient-free parameters optimizing barren plateau quantum noise

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Handwritten digit recognition based on ghost imaging with deep learning

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Chinese Physics B 2021年第5期30卷 367-372页

作者： Xing He Sheng-Mei Zhao Le Wang Institute of Signal Processing and Transmission Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Laboratory of Broadband Wireless Communication and Sensor Network Technology(Ministry of Education) Nanjing 210003China

We present a ghost handwritten digit recognition method for the unknown handwritten digits based on ghost imaging(GI)with deep neural network,where a few detection signals from the bucket detector,generated by the cosine transform speckle,are used as the characteristic information and the input of the designed deep neural network(DNN),and the output of the DNN is the *** results show that the proposed scheme has a higher recognition accuracy(as high as 98%for the simulations,and 91%for the experiments)with a smaller sampling ratio(say 12.76%).With the increase of the sampling ratio,the recognition accuracy is *** with the traditional recognition scheme using the same DNN structure,the proposed scheme has slightly better performance with a lower complexity and non-locality *** proposed scheme provides a promising way for remote sensing.

关键词： ghost imaging handwritten digit recognition ghost handwritten recognition deep learning

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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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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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