直流支撑电容器,又称DC-Link电容器。直流支撑电容器,属于无源器件的一种。直流支撑电容器,现主要采用聚丙烯薄膜介质直流支撑电容器,其具有耐电压高、耐电流大、低阻抗、低电感、容量损耗小、漏电流小、温度性能好、充放电速度快、使用寿命长(约10万小时)、安全防爆稳定性好、无极性安装方便等优点。被广泛应用于电力电子行业
上传时间: 2019-06-16
上传用户:abcdyifei
pcie3.0标准规范 1. INTRODUCTION 2. TRANSACTION LAYER SPECIFICATION 3. DATA LINK LAYER SPECIFICATION 4. PHYSICAL LAYER SPECIFICATION 5. POWER MANAGEMENT 6. SYSTEM ARCHITECTURE 7. SOFTWARE INITIALIZATION AND CONFIGURATION
标签: pcie3
上传时间: 2019-07-05
上传用户:bingshi
One traditional view of how wireless networks evolve is of a continuous, inevitable progres- sion to higher link speeds, combined with greater mobility over wider areas. This standpoint certainly captures the development from first and second generation cellular systems focused on voice support, and the early short-range wireless data networks, through to today’s 3G cellular and mobile broadband systems; there is every confidence that the trend will continue some way into the future.
上传时间: 2020-05-26
上传用户:shancjb
Cognitive radio has emerged as a promising technology for maximizing the utiliza- tion of the limited radio bandwidth while accommodating the increasing amount of services and applications in wireless networks. A cognitive radio (CR) transceiver is able to adapt to the dynamic radio environment and the network parameters to maximize the utilization of the limited radio resources while providing flexibility in wireless access. The key features of a CR transceiver are awareness of the radio envi- ronment (in terms of spectrum usage, power spectral density of transmitted/received signals, wireless protocol signaling) and intelligence.
标签: Cognitive Wireless Network
上传时间: 2020-05-26
上传用户:shancjb
Designing for Networked Communications: Strategies and Development is a book about how we plan, use, and understand the products, dynamic social processes, and tasks upon which depend some of the most vital innovations in the knowledge society—social as well as technological ones. Focusing on various forms of design, implementation, and integration of computer-mediated communication (CMC), the book bridges the academic fields of computer science and communication stud- ies.
标签: Communications Designing Networked for
上传时间: 2020-05-27
上传用户:shancjb
This thesis is about wireless communication in shared radio spectrum. Its origin and motivation is ideally represented by the two quotations from above. In this thesis, the support of Quality-of-Service (QoS) in cognitive radio networks is analyzed. New approaches to distributed coordination of cognitive radios are developed in different spectrum sharing scenarios. The Wireless Local Area Network (WLAN) 802.11 proto- col of the Institute of Electrical and Electronics Engineers (IEEE) (IEEE, 2003) with its enhancement for QoS support (IEEE, 2005d) is taken as basis. The Medium Access Control (MAC) of 801.11(e) is modified to realize flexible and dynamic spectrum assignment within a liberalized regulation framework.
标签: Quality-of-Service Distributed Support
上传时间: 2020-05-27
上传用户:shancjb
Multiuser multiple-input-multiple-output (MU- MIMO) systems are known to be hindered by dimensionality loss due to channel state information (CSI) acquisition overhead. In this paper, we investigate user-scheduling in MU-MIMO systems on account of CSI acquisition overhead, where a base station dynamically acquires user channels to avoid choking the system with CSI overhead.
标签: Acquisition Dynamic Channel
上传时间: 2020-05-27
上传用户:shancjb
During the past decade, many wireless communication techniques have been developedto achievevariousgoals suchas higherdata rate,morerobustlink quality, and higher number of users in a given bandwidth. For wireless communication systems, depending on the availability of a feedback link, two approaches can be considered: namely open and closed loop. Open loop communication system that does not exploit the channel knowledge at the transmitter is now well understood from both a theoretical and practical point of view.
标签: Communication Strategies Feedback Wireless for
上传时间: 2020-05-27
上传用户:shancjb
The recent developments in full duplex (FD) commu- nication promise doubling the capacity of cellular networks using self interference cancellation (SIC) techniques. FD small cells with device-to-device (D2D) communication links could achieve the expected capacity of the future cellular networks (5G). In this work, we consider joint scheduling and dynamic power algorithm (DPA) for a single cell FD small cell network with D2D links (D2DLs). We formulate the optimal user selection and power control as a non-linear programming (NLP) optimization problem to get the optimal user scheduling and transmission power in a given TTI. Our numerical results show that using DPA gives better overall throughput performance than full power transmission algorithm (FPA). Also, simultaneous transmissions (combination of uplink (UL), downlink (DL), and D2D occur 80% of the time thereby increasing the spectral efficiency and network capacity
标签: Full-Duplex Cells Small
上传时间: 2020-05-27
上传用户:shancjb
With the rapid expansion of wireless consumer products,there has been a con- siderable increase in the need for radio-frequency (RF) planning, link plan- ning, and propagation modeling.A network designer with no RF background may find himself/herself designing a wireless network. A wide array of RF planning software packages can provide some support, but there is no substi- tute for a fundamental understanding of the propagation process and the lim- itations of the models employed. Blind use of computer-aided design (CAD) programs with no understanding of the physical fundamentals underlying the process can be a recipe for disaster. Having witnessed the results of this approach, I hope to spare others this frustration.
标签: Introduction Propagation to RF
上传时间: 2020-05-27
上传用户:shancjb