Software Radio (SR) is one of the most important emerging technologies for the future of wireless communication services. By moving radio functionality into software, it promises to give flexible radio systems that are multi-service, multi- standard, multi-band, reconfigurable and reprogrammable by software. Today’s radios are matched to a particular class of signals that are well defined bytheircarrierfrequencies,modulationformatsandbandwidths.Aradiotransmitter today can only up convert signals with well-defined bandwidths over defined center frequencies, while, on the other side of the communication chain, a radio receiver can only down convert well-defined signal bandwidths, transmitted over specified carrier frequencies.
上傳時間： 2020-06-01
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Part I provides a compact survey on classical stochastic geometry models. The basic models defined in this part will be used and extended throughout the whole monograph, and in particular to SINR based models. Note however that these classical stochastic models can be used in a variety of contexts which go far beyond the modeling of wireless networks. Chapter 1 reviews the definition and basic properties of Poisson point processes in Euclidean space. We review key operations on Poisson point processes (thinning, superposition, displacement) as well as key formulas like Campbell’s formula. Chapter 2 is focused on properties of the spatial shot-noise process: its continuity properties, its Laplace transform, its moments etc. Both additive and max shot-noise processes are studied. Chapter 3 bears on coverage processes, and in particular on the Boolean model. Its basic coverage characteristics are reviewed. We also give a brief account of its percolation properties. Chapter 4 studies random tessellations; the main focus is on Poisson–Voronoi tessellations and cells. We also discuss various random objects associated with bivariate point processes such as the set of points of the first point process that fall in a Voronoi cell w.r.t. the second point process.
標簽： Stochastic Geometry Networks Wireless Volume and
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n the first part of this book, we give an introduction to the basic applications of wireless com- munications, as well as the technical problems inherent in this communication paradigm. After a brief history of wireless, Chapter 1 describes the different types of wireless services, and works out their fundamental differences. The subsequent Section 1.3 looks at the same problem from a different angle: what data rates, ranges, etc., occur in practical systems, and especially, what combination of performance measures are demanded (e.g., what data rates need to be transmitted over short distances; what data rates are required over long distances?) Chapter 2 then describes the technical challenges of communicating without wires, putting special emphasis on fading and co-channel interference. Chapter 3 describes the most elementary problem of designing a wireless system, namely to set up a link budget in either a noise-limited or an interference-limited system. After studying this part of the book, the reader should have an overview of different types of wireless services, and understand the technical challenges involved in each of them. The solutions to those challenges are described in the later parts of this book.
標簽： Communications Wireless Edition 2nd
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Welcome to the third volume of the book entitled Technologies for the Wireless Future, which is produced by WWRF. The idea is to take the most important outputs from the working groups and special-interest groups that compose the Forum and bring them together in a series of one-volume surveys. The latest of these will give the reader a good overview of the WWRF approach to analyzing the future of wireless and mobile communications, as well as an insight into the trends themselves and the key technologies that will be deployed.
標簽： Wireless Research Forum World
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The purpose of this preface is twofold. Firstly, to give an informal historical introduction to the subject area of this book, Systems and Control, and secondly, to explain the philosophy of the approach to this subject taken in this book and to outline the topics that will be covered.
標簽： Introduction Mathematical Theory the to
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In this chapter we give a quick overview of control theory, explaining why integral feedback control works, describing PID controllers, and summariz- ing some of the currently available techniques for PID controller design. This background will serve to motivate our results on PID control, pre- sented in the subsequent chapters.
標簽： Controllers Time-Delay Systems PID for
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Artificial Intelligence (AI) has undoubtedly been one of the most important buz- zwords over the past years. The goal in AI is to design algorithms that transform com- puters into “intelligent” agents. By intelligence here we do not necessarily mean an extraordinary level of smartness shown by superhuman; it rather often involves very basic problems that humans solve very frequently in their day-to-day life. This can be as simple as recognizing faces in an image, driving a car, playing a board game, or reading (and understanding) an article in a newspaper. The intelligent behaviour ex- hibited by humans when “reading” is one of the main goals for a subfield of AI called Natural Language Processing (NLP). Natural language 1 is one of the most complex tools used by humans for a wide range of reasons, for instance to communicate with others, to express thoughts, feelings and ideas, to ask questions, or to give instruc- tions. Therefore, it is crucial for computers to possess the ability to use the same tool in order to effectively interact with humans.
標簽： Embeddings Processing Language Natural in
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在半導體制冷技術的工作性能及其優缺點研究的基礎上,設計了以單片機為核心控制元件,以TEC1-12706為執行元件的半導體制冷溫度控制系統。采用高精度分段式PID控制算法配合PWM輸出控制的方法實現溫度控制;選擇數字傳感器DS18B20為溫度檢測元件,還包含1602液晶顯示模塊、按鍵調整輸入模塊和H橋驅動模塊等。實際測試表明,該系統結構簡單易行,操作方便,工作性能優良,同時針對該系統專門設計的溫控算法,使半導體制冷器能更好地適應不同工況而充分發揮其制冷制熱工作特性。Based on the study of the performance and advantages and disadvantages of thermoelectric cooler(TEC)technology,a thermoelectric cooling temperature control system with single-chip microcomputer as the core control element and TEC1-12706 as the executive element was designed. High precision piecewise PID control algorithm combined with PWM output control method is adopted to realize temperature control. The digital sensor DS18B20 is selected as the temperature detection element. It also includes 1602 LCD module,key adjustment input module and H bridge drive module. The actual test shows that the system has simple structure,convenient operation and excellent performance. Meanwhile,the temperature control algorithm specially designed for the system can make the semiconductor cooler better adapt to different working conditions and give full play to its refrigeration and heating characteristics.
上傳時間： 2022-03-27
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為解決移相全橋電路驅動及相角控制問題,設計了一種數字控制的移相全橋驅動電路.以TPL521為光耦隔離、IR2110為柵極驅動芯片.由DSP產生PWM信號,經過光耦隔離和邏輯電路后送至IR2110進行相角控制.文章對IR2110驅動電路原理進行分析及參數進行設計,對TMS320F28335進行設置并給出部分代碼.實驗結果表明：通過TMS320F28335可產生的不同相角的PWM波形,滿足了移相全橋對不同相角控制的要求.In order to solve the problem of phase-shifted full-bridge circuit driving and phase angle control,a digitally controlled phaseshifted full-bridge driving circuit was designed. TPL521 optocoupler isolation,IR2110 gate driver chip. PWM signals are generated by the DSP and sent to the IR2110 for phase angle control after optocoupler isolation and logic circuits. This text carries on the analysis to the principle of IR2110 drive circuit and parameter design,set up and give out some code to TMS320F28335. The experimental results show that the PWM waveforms with different phase angles generated by TMS320F28335 can meet the requirements of phase-shifted full-bridge control for different phase angles.
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This documentation is the original work and copyrighted property of X-Powers. Reproduction in whole orin part must obtain the written approval of X-Powers and give clear acknowledgement to the copyrightowner.
標簽： AC101
上傳時間： 2022-06-28
上傳用戶：xsr1983
