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Quantum-enhanced interferometry with asymmetric beam splitters

Science China(Physics,Mechanics & Astronomy) 2020年第6期63卷 22-32页

作者： Wei Zhong Fan Wang Lan Zhou Peng Xu YuBo Sheng Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing 210003China

In this paper,we investigate the phase sensitivities in two-path optical interferometry with asymmetric beam ***,we present the optimal conditions for the transmission ratio and the phase of the beam splitter to gain the highest sensitivities for a general class of non-classical states with parity ***,we address the controversial question of whether the scheme with a combination of coherent state and photon-added or photon-subtracted squeezed vacuum state is better or worse than the most celebrated one using a combination of coherent state and squeezed vacuum state.

关键词： quantum metrology quantum Fisher information Heisenberg limit optical interferometry

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Efficient Rate Control Algorithm for Multi-view Video Coding

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China communications 2011年第3期8卷 83-89页

作者：刘峰熊婕范晶晶林琼洁 Image Processing & Image Communication Key Lab of Jiangsu Province Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of Education

Rate control is one of the key factors influencing the multi-view video ***,there is not a rate control algorithm in the existing Joint Multi-view Video Coding *** this paper,an efficient rate control algorithm and a bit allocation strategy for multi-view video coding are *** order to obtain the consistent view quality,a bit allocation model based on the Lagrange optimum algorithm is firstly ***,considering the encoding statistical characteristics of different view types,a view weighting factor is introduced,and it will help improve the precision of bit allocation among *** with the fixed QP control strategy,experiment results show that the proposed algorithm can efficiently control the bit rate and obtain more consistent views,with video visual quality improved.

关键词： rate control rate distortion bit allocation view weighting factor

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Efficient separating orbital angular momentum mode with radial varying phase

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Photonics Research 2017年第4期5卷 267-270页

作者： CHENG LI SHENGMEI ZHAO Institute of Signal Processing and Transmission Nanjing University of Posts and Telecommunications Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education

It is shown that orbital angular momentum(OAM) is a promising new resource in future classical and quantum communications. However, the separation of OAM modes is still a big challenge. In this paper, we propose a simple and efficient separation method with a radial varying phase. In the method, specific radial varying phases are designed and modulated for different OAM modes. The resultant beam is focused to the spots with different horizontal and vertical positions after a convex lens, when the coordinate transformation, including two optical elements with coordinate transformation phase and correct phase, operates on the received *** horizontal position of the spot is determined by the vortex phases, and the vertical position of the spot is dependent on the radial varying phases. The simulation and experimental results show that the proposed method is feasible both for separation of two OAM modes and separation of three OAM modes. The proposed separation method is available in principle for any neighboring OAM modes because the radial varying phase is controlled. Additionally, no extra instruments are introduced, and there is no diffraction and narrowing process limitation for the separation.

关键词： OAM Efficient separating orbital angular momentum mode with radial varying phase mode

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A quantum search based signal detection for MIMO-OFDM systems

A quantum search based signal detection for MIMO-OFDM system...

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2011 18th International Conference on Telecommunications, ICT 2011

作者： Li, Fei Zhou, Lizhi Liu, Li Li, Haibo Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunication Ministry of Education Nanjing China Department of Applied Physics and Electronics Umeå University Umeå Sweden

ISBN: (纸本)9781457700248

Multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) is considered as candidates for future broadband wireless services. In this paper a novel signal detection scheme based on Grover's quantum search algorithm is proposed for MIMO-OFDM systems. Grover's quantum search algorithm is based on the concept and principles of quantum computing, such as quantum bit, quantum register and quantum parallelism. An analysis is given to the theoretical basis of Grover's algorithm and the performance of Grover's algorithm is evaluated. A novel signal detector based on Grover's algorithm (GD) for MIMO-OFDM system is proposed. The simulation results show that the proposed detector has more powerful properties in bit error rate than MMSE detector and VBLAST-MMSE detector. The performance of the proposed GD detector is close to optimal when the failure probability is 0.001. When the failure probability is 0.00001, the performance of GD detector declines. In this case, our proposed improved Grover's algorithm based detector is still close to the optimal ML detector. The complexity of GD and IGD is O(√N). It's much better than classical ML detector which complexity is O(N). © 2011 IEEE.

关键词： Orthogonal frequency division multiplexing

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Cognitive radio spectrum sharing using improved Quantum Genetic Algorithm

Cognitive radio spectrum sharing using improved Quantum Gene...

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2011 International Conference on wireless communications and Signal Processing, WCSP 2011

作者： Li, Fei Zhu, Dongpo Tian, Feng Li, Haibo Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing China Department of Applied Physics and Electronics Umeå University Umeå Sweden

ISBN: (纸本)9781457710100

A key challenge in cognitive radios (CR) network is how to adaptively and efficiently allocate transmission powers and spectrum among CR users according to the surrounding environment. In this paper, we propose a novel spectrum sharing based on our improved Quantum Genetic Algorithm (QGA) in a non-cooperative game for CR network. We improved the original QGA by quantum crossover operator, in order to overcome the shortcoming of the original QGA easily falling into a local extremum when used to optimize the continuous functions with many extrema. We used our improved QGA as a competitive strategy and conducted several simulations in two-user system and multi-user system. From simulation results, it is evident that the proposed improved QGA based spectrum sharing scheme has better convergence rate and higher sum capacity than GA based scheme even in multi-user CR system, namely up to 2bit/s/Hz increase in capacity. The simulation results also show that the population size of QGA affect sum capacity of cognitive radio system. The results demonstrated the effectiveness and the applicability of QGA in spectrum sharing in multi-user cognitive radio system. © 2011 IEEE.

关键词： Cognitive radio

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Optimization on Cooperative communications Based on network Coding in Multi-hop wireless networks 16

Optimization on Cooperative Communications Based on Network ...

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16th IEEE International wireless communications and Mobile Computing Conference, IWCMC 2020

作者： Bu, Xiande Liu, Chuan Yu, Qiang Yin, Lei Tian, Feng State Grid Laboratory of Electric Power Communication Network Global Energy Interconnection Research Institute Nanjing210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing Universityof Posts and Telecommunications Ministry of Education Nanjing210003 China

ISBN: (纸本)9781728131290

Cooperative communications (CC) based on network coding (NC) can significantly increase the capacity of wireless networks. In this paper, we investigate how to apply NC in multi-hop wireless networks with multiple relay nodes and multiple sessions to achieve more practical and general CC based on NC. Based on NC, we consider to jointly optimize relay node selecting, scheduling and flow routing in CC in a multi-hop wireless network. We not only construct a mathematical model but also formulate a maximum-minimum (Max-Min) optimization problem for it. Then we reformulate and solve it with CPLEX. Through simulation, we validate that the achieved rate gain by NC can be greatly improved than the one by CC. © 2020 IEEE.

关键词： Cooperative communication

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An expanding ring prediction and location aided AODV routing algorithm

An expanding ring prediction and location aided AODV routing...

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2011 International Conference on Information technology, Computer Engineering and Management Sciences, ICM 2011

作者： Cheng, Chunling Hao, Jingbo Zhang, Dengyin College of Computer Nanjing University of Posts and Telecommunications Nanjing Jiangsu 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Jiangsu Province Nanjing Jiangsu 210003 China

ISBN: (纸本)9780769545226

On the battlefield, the cooperative fighting and communication among combat vehicles require higher service level of real-time transmission. Combat vehicles' fast moving and the links' frequent disruption lead to the increase of packet loss rate, packet delay and routing control overhead ratio. This paper proposes an expanding ring prediction and location aided AODV routing algorithm. It improves AODV routing protocol from both routing discovery and maintenance phases. In the rouing discovery phase, the algorithm limits the scope of sending RREQ through predicting the topology ring;and during the route maintenance phase, it predicts the motion range of destination node with the information provided by GPS to avoid blindness routing. The simulation results show that the proposed routing algorithm can greatly cut down the overload of combat vehicular network, improve the routing delay and reduce packet loss rate. It can meet the real-time requirements of the service transmission among combat vehicles and also improve the performance of the combat vehicular network. © 2011 IEEE.

关键词： Forecasting

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Gossip-based indexing ring topology for 2-dimension spatial data in overlay networks

Gossip-based indexing ring topology for 2-dimension spatial ...

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2012 International Workshop on Information and Electronics Engineering, IWIEE 2012

作者： Zou, Z.Q. Wang, Y. Hu, B. Wang, R.C. College of Computer Nanjing University of Posts and Telecommunications Nanjing Jiangsu 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu 210003 China Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Jiangsu Province Nanjing Jiangsu 210003 China

Overlay networks are used widely in the Internet, such as retrieval and share of files, multimedia games and so on. However, in distributed system, the retrieval and share of 2-dimension spatial data still have some difficult problems and can not solve the complex retrieval of 2-dimension spatial data efficiently. This article presents a new indexing overlay networks, named 2D-Ring, which is the ring topology based on gossip for 2-dimension spatial data. The peers in our overlay networks exchange the information periodically and update each local view by constructing algorithm. 2-dimension spatial data is divided by quad-tree and mapped into control points, which are hashed into 2D-Ring by SHA-1 hash function. In such way, the problem of 2-dimension spatial data indexing is converted to the problem of searching peers in the 2D-Ring. A large of extensive experiments show that the time complexity of constructing algorithm of 2D-Ring can reach convergence logarithmically as a function of the network size and hold higher hit rate and lower query delay. © 2011 Published by Elsevier Ltd.

关键词： Overlay networks

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Design and implementation of low power consumption wireless pressure transmitter monitoring system

Design and implementation of low power consumption wireless ...

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2009 International Conference on Computational Intelligence and Software Engineering, CiSE 2009

作者： Wang, Quan Liu, Zhe Wang, Ping Wei, Min Ministry of Education Key Lab. of Network Control and Intelligent Instrument Chongqing University of Posts and Telecommunications Chongqing China Key Laboratory of Wireless Sensor Network and Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai China

ISBN: (纸本)9781424445073

Recent years have seen a burgeoning interest in industrial wireless network with applications ranging from filed monitoring to controlling. Industrial wireless network have several important attributes that require special attention to device design which include the need for inexpensive, long-lasting, highly reliable devices coupled with very low performance requirements. Aimed at key issues of limited battery energy and reduction power consumption, combined with the soul of intelligent instrumentation a low-power consumption design of wireless pressure transmitter was proposed and realized. This paper outlined the system design, and introduced the design of the network protocol stack structure with sleep-wakeup mechanism in detail. The testing and analysis results show that the system has both high stability and great low-power consumption. ©2009 IEEE.

关键词： network protocols

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A Survey of Trusted network Trust Evaluation Methods 2nd

A Survey of Trusted Network Trust Evaluation Methods

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2nd EAI International Conference on Security and Privacy in New Computing Environments, SPNCE 2019

作者： Yin, An-Sheng Zhang, Shun-Yi Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Nanjing210023 China Department of Internet of Things Nanjing University of Posts and Telecommunications Nanjing210023 China

ISBN: (纸本)9783030213725

The proposed trusted network is respond to the increasingly prominent internal network security threats. At present, research on trusted networks focuses on two aspects: pre-network access check and dynamic evaluation after access. The pre-access check considers the integrity of the terminal and uses encryption and authentication methods to achieve it. The dynamic evaluation uses the static and dynamic attributes of the trust to implement trust evaluation. © 2019, ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering.

关键词： network security

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