|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Energy-efficient cell-association bias adjustment algorithm for ultra-dense networks显示文摘In recent years, energy efficiency has become an important topic, especially in the field of ultradense networks(UDNs). In this area, cell-association bias adjustment and small cell on/off are proposed to enhance the performance of energy efficiency in UDNs. This is done by changing the cell association relationship and turning off the extra small cells that have no users. However, the variety of cell association relationships and the switching on/off of the small cells may deteriorate some users' data rates, leading to nonconformance to the users' data rate requirement. Considering the discreteness and non-convexity of the energy efficiency optimization problem and the coupled relationship between cell association and scheduling during the optimization process, it is difficult to achieve an optimal cell-association bias. In this study, we optimize the network energy efficiency by adjusting the cell-association bias of small cells while satisfying the users' data rate requirement. We propose an energy-efficient centralized Gibbs sampling based cell-association bias adjustment(CGSCA) algorithm. In CGSCA, global information such as channel state information, cell association information, and network load information need to be collected. Then, considering the overhead of the messages that are exchanged and the implementation complexity of CGSCA to obtain the global information in UDNs, we propose an energy-efficient distributed Gibbs sampling based cell-association bias adjustment(DGSCA) algorithm with a lower message-exchange overhead and implementation complexity.Using DGSCA, we derive the updated formulas for calculating the number of users in a cell and the users' SINR. We analyze the implementation complexities(e.g., computation complexity and communication complexity) of the proposed two algorithms and other existing algorithms. We perform simulations, and the results show that CGSCA and DGSCA have faster convergence speed, as well as a higher performance gain of the energy efficiency and throughput compared to other existing algorithms. In addition, we analyze the importance of the users' data rate constraint in optimizing the energy efficiency, and we compare the energy efficiency performance of different algorithms with different number of small cells. Then, we present the number of sleeping small cells as the number of small cells increases. | Wenxiang ZHU Pingping XU Thi Oanh BUI Guilu WU Yan YANG | 2018 | Science China(Information Sciences)2018，61，2： | 1 |
| 2 | Control problems in quantum systems显示文摘The past decade or two has witnessed tremendous progress in theory and practice of quantum control technologies.Bridging different scientific disciplines ranging from fundamental particle physics to nanotechnology,the goal of quantum control has been to develop effective and efficient tools for common analysis and design,but more importantly would pave the way for future technological applications.This article briefly reviews basic quantum control theory from the perspective of modeling,analysis and design,as well as considers future research directions. | WU ReBing ZHANG Jing LI ChunWen LONG GuiLu TARN TzyhJong | 2012 | Chinese Science Bulletin2012，57，18： | 1 |
| 3 | Quantum secure direct communication with entanglement source and single-photon measurement显示文摘Quantum secure direct communication(QSDC)transmits information directly over a quantum channel.In addition to security in transmission,it avoids loopholes of key loss and prevents the eavesdropper from getting ciphertext.In this article,we propose a QSDC protocol using entangled photon pairs.This protocol differs from existing entanglement-based QSDC protocols because it does not perform Bell-state measurement,and one photon of the entangled pair is measured after the entanglement distribution.It has the advantage of high signal-to-noise ratio due to the heralding function of entanglement pairs,and it also has the relative ease in performing single-photon measurement.The protocol can use a practical entanglement source from spontaneous parametric down-conversion(SPDC);Gottesman-Lo-Lu¨tkenhaus-Preskill theory and the decoy state method give a better estimate of the error rate.Security analysis is completed with Wyner’s wiretap channel theory,and the lower bound of the secrecy capacity is estimated.Numerical simulations were carried out to study the performance of the protocol.These simulations demonstrated that the protocol with a practical SPDC entanglement source performed well and was close to the case with an ideal entanglement source. | Lu Yang JiaWei Wu ZaiSheng Lin LiuGuo Yin GuiLu Long | 2020 | Science China(Physics,Mechanics & Astronomy)2020，63，11： | 1 |
| 4 | Link QoS analysis of 5G-enabled V2V network based on vehicular cloud显示文摘Dear editor,The fifth generation (5G) communication technologies, especially for millimeter wave (mm Wave)technology, have a huge application for satisfying different service requirements in vehicular networks, e.g., the vehicle-to-vehicle (V2V) network.In the mm Wave V2V network, a reliable link quality-of-service (Qo S) is particularly important because it brings reliable message transmissions for various service requirements. For a | Guilu WU Pingping XU | 2018 | Science China(Information Sciences)2018，61，10： | 0 |
| 5 | OFF-grid full-dimension channel estimation for mm Wave/THz systems with angular block prior显示文摘Dear editor,The acquirement of the channel state information(CSI) is indispensable for designing efficient beamformers [1]. Unfortunately, estimating CSI is extremely challenging in the mm Wave/THz systems where the number of antennas is super-large and the receive signal-to-noise ratio(SNR) is relatively low. Most of the existing estimators are based on the direct applications of inherent channel sparsity and generic compressive sensing(CS) techniques, which cannot lead to fine enough performances in channel estimation because it puts strict requirements on the channel sparsity or the data measurements [2–7]. | Hongyun CHU Wei FENG Maoqi LI Zhichao ZHU Guilu WU | 2021 | Science China(Information Sciences)2021，64，11： | 0 |
您所在的机构暂未开通此部分的功能，请联系管理员