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
標簽: Full-Duplex Cells Small
上傳時間: 2020-05-27
上傳用戶:shancjb
In this paper we revisit hybrid analog-digital precoding systems with emphasis on their modelling and radio-frequency (RF) losses, to realistically evaluate their benefits in 5G system implementations. For this, we decompose the analog beamforming networks (ABFN) as a bank of commonly used RF components and formulate realistic model constraints based on their S-parameters. Specifically, we concentrate on fully-connected ABFN (FC-ABFN) and Butler networks for implementing the discrete Fourier transform (DFT) in the RF domain. The results presented in this paper reveal that the performance and energy efficiency of hybrid precoding systems are severely affected, once practical factors are considered in the Overall design. In this context, we also show that Butler RF networks are capable of providing better performances than FC-ABFN for systems with a large number of RF chains.
標簽: Analog-Digital Precoding Hybrid
上傳時間: 2020-05-27
上傳用戶:shancjb
Microwave radio network design is a subset of activities that constitute the Overall transmission network design. Transmission networks are sometimes called transport networks, access networks, or connectivity networks. For many wireless carriers, microwave is becoming a popu- lar preference over wireline (leased lines) transport for many reasons, especially as microwave radio equipment costs decrease and installation becomes simpler. Low monthly operating costs can undercut those of typical single (and especially multiple) T1/E1 expenses, proving it to be more economical over the long term—usually two to four years. Network operators also like the fact that they can own and control microwave radio networks instead of relying on other service providers for network components.
標簽: Transmission Microwave Networks
上傳時間: 2020-05-28
上傳用戶:shancjb
This book presents millimeter wave communication system design and analysis at the level to produce an understanding of the interaction between a wireless system and its front end so that the Overall performance can be predicted. Gigabit wireless commu- nications require a considerable amount of bandwidth, which can be supported by millimeter waves. Millimeter wave technology has come of age, and at the time of writing the standards of IEEE 802.15.3c, WiGig, Wireless HD TM , and the European Computer Manufacturers Association have recently been finalized.
標簽: Communication Millimeter Systems Wave
上傳時間: 2020-05-28
上傳用戶:shancjb
Use of multiple antennas at both ends of wireless links is the result of the natural progression of more than four decades of evolution of adaptive antenna technology. Recent advances have demonstrated that multiple- input-multiple-output (MIMO) wireless systems can achieve impressive increases in Overall system performance.
標簽: Technology System MIMO
上傳時間: 2020-05-28
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Never have telecommunications operations and network management been so important. Never has it been more important to move away from practices that date back to the very beginning of the telecommunications industry. Building and con- necting systems internally at low cost, on an as - needed basis, and adding software for supporting new networks and services without an Overall architectural design will not be cost effective for the future. Defi ning operations and network manage- ment requirements at the 11th hour for new technologies, networks, and services deployments must also change.
標簽: Telecommunications Generation Networks Next
上傳時間: 2020-05-31
上傳用戶:shancjb
Modeling and simulation of nonlinear systems provide communication system designers with a tool to predict and verify Overall system performance under nonlinearity and complex communication signals. Traditionally, RF system designers use deterministic signals (discrete tones), which can be implemented in circuit simulators, to predict the performance of their nonlinear circuits/systems. However, RF system designers are usually faced with the problem of predicting system performance when the input to the system is real-world communication signals which have a random nature.
標簽: Nonlinear_Distortion_in_Wireless_ Systems
上傳時間: 2020-05-31
上傳用戶:shancjb
The ever-increasing demand for private and sensitive data transmission over wireless net- works has made security a crucial concern in the current and future large-scale, dynamic, and heterogeneous wireless communication systems. To address this challenge, computer scientists and engineers have tried hard to continuously come up with improved crypto- graphic algorithms. But typically we do not need to wait too long to find an efficient way to crack these algorithms. With the rapid progress of computational devices, the current cryptographic methods are already becoming more unreliable. In recent years, wireless re- searchers have sought a new security paradigm termed physical layer security. Unlike the traditional cryptographic approach which ignores the effect of the wireless medium, physi- cal layer security exploits the important characteristics of wireless channel, such as fading, interference, and noise, for improving the communication security against eavesdropping attacks. This new security paradigm is expected to complement and significantly increase the Overall communication security of future wireless networks.
標簽: Communications Physical Security Wireless Layer in
上傳時間: 2020-05-31
上傳用戶:shancjb
HIS IS THE THIRD —and most likely the last—book in the series on information technology for energy managers and web based energy infor- mation and control systems. This book concentrates on web based enterprise energy and building automation systems, and serves as a capstone volume in this series. The thrust here is that the highest level functions of a building and facility automation system are provided by a web based EIS/ECS system that provides energy management, maintenance management, Overall facility operational management, and ties in with the enterprise resource management system for the entire facility or the group of facilities being managed. If there were ever to be a fourth volume in this series, it would follow the logical progression of the first three volumes, and would probably be titled Web Based Enterprise Resource Management Systems.
標簽: Enterprise Energy Based Web
上傳時間: 2020-06-06
上傳用戶:shancjb
GaN is an already well implanted semiconductor technology, widely diffused in the LED optoelectronics industry. For about 10 years, GaN devices have also been developed for RF wireless applications where they can replace Silicon transistors in some selected systems. That incursion in the RF field has open the door to the power switching capability in the lower frequency range and thus to the power electronic applications. Compared to Silicon, GaN exhibits largely better figures for most of the key specifications: Electric field, energy gap, electron mobility and melting point. Intrinsically, GaN could offer better performance than Silicon in terms of: breakdown voltage, switching frequency and Overall systems efficiency.
標簽: GaN-on-Si Displace and SiC Si
上傳時間: 2020-06-07
上傳用戶:shancjb