Theory and applications of ofdm and cdma wideband wireless communications phần 1 ppsx

Multi-Carrier Digital Communications - Theory and Applications of OFDM

... Polytechnic Institute and State UniversityBlacksburg, Virginia Multi-Carrier Digital Communications: Theory and Applications of OFDM Ahmad R. S. Bahai and Burton R. SaltzbergPrinciples of Digital Transmission: ... requirement of an equalizer in a typical single carrierimplementation for wireline applications. Multi-Carrier Digital Communications Theory and Applications of OFDM Ahmad R. S. Bahai and Burton ... introduced into the design of Multi-Carrier Digital Communications Theory and Applications of OFDM System Architecture 27complex multiplication is performed before the add-subtract operation, whilein...

Tài liệu Obesity guidance on the prevention, identification, assessment and management of overweight and obesity in adults and children ppt

... catering (including vending machines) and the food and drink children bring into school, the taught curriculum (including PE), school travel plans and provision for cycling, and policies relating ... Section 3 on pages 59 and 60 has links to tools to help with implementing the recommendations, meeting training needs, evaluating the impact of action and working in partnership with other ... Decisions on the approach to management of a child’s overweight or obesity (including assessment and agreement of goals and actions) should be made in partnership with the child and family, and...

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Obesity guidance on the prevention, identification, assessment and management of overweight and obesity in adults and children docx

... evidence of effectiveness, including cost effectiveness. They include recommendations on the clinical management of overweight and obesity in the NHS, and advice on the prevention of overweight and ... overweight and obesity in adults and children in England and Wales. The guidance aims to: ã stem the rising prevalence of obesity and diseases associated with it ã increase the effectiveness of interventions ... standards (see recommendation 1.1.7.1). NICE clinical guideline 43 33 Introduction This is the first national guidance on the prevention, identification, assessment and management of overweight...

Multi-Carrier Digital Communications Theory and Applications of OFDM pdf

... symbols to OFDM symbolssuch thatThe linear mapping can be represented in matrix form as:17 Multi-Carrier Digital Communications Theory and Applications of OFDM Ahmad R. S. Bahai and Burton ... TECHNIQUES FOR WIRELESS LAN OFDM FOR WIRELESS LAN RECEIVER STRUCTURE 175181182187 Multi-Carrier Digital Communications Theory and Applications of OFDM 22 System ArchitectureFigure ... high volume of papers appearing in technical journals and conferences.This book is intended to be a concise summary of the present state of theart of the theory and practice of OFDM technology....

Theory and applications of ofdm and cdma wideband wireless communications phần 1 ppsx

... BibliographicalNotes 14 23.5 Problems 14 34 OFDM 14 54 .1 GeneralPrinciples 14 54 .1. 1 Theconceptofmulticarriertransmission 14 54 .1. 2 OFDMasmulticarriertransmission 14 94 .1. 3 ImplementationbyFFT 15 34 .1. 4 OFDMwithguardinterval ... by the signals(t) =Kk =1 skgk(t). (1. 17) Theory and Applications of OFDM and CDMA Wideband Wireless Communications Henrik Schulze and Christian LăudersBoth of Fachhochschule SăudwestfalenMeschede, ... ContentsPreface ix 1 Basics of Digital Communications 1 1 .1 Orthogonal Signals and Vectors . . . . . . . . . . . . . . . . . . . . . . . . 1 1 .1. 1 TheFourierbasesignals 1 1 .1. 2 Thesignalspace 5 1. 1.3 Transmitters...

Theory and applications of ofdm and cdma wideband wireless communications phần 2 ppt

... gain|c(t)| 2 of the channel can be calculated as|c(t)| 2 = a 2 1+ a 2 2+ 2a1a 2 cos( 2 (ν1− ν 2 )t +θ1− θ 2 ).Figure 2. 4 shows|c(t)| 2 for a1= 0.75 and a 2 =√7/4. The ... gain|H(f)| 2 of the channel can becalculated as|H(f)| 2 = a 2 1+ a 2 2+ 2a1a 2 cos( 2 f(τ1− τ 2 )+ θ 2 − θ1).The picture is similar to the one depicted in Figure 2. 4, where ... φ) asQ(x) =π /2 −π /2 ∞x/ cos φr 2 exp−1 2 r 2 drdφ. (1.90)The integral over r can immediately be solved to giveQ(x) =π /2 −π /2 1 2 exp−1 2 x 2 cos 2 φdφ. (1.91)A...

Theory and applications of ofdm and cdma wideband wireless communications phần 3 ppt

... is often convenient to work with code words of ﬁnite length, but it is not necessary, and the length is not determined by the code. Theory and Applications of OFDM and CDMA Henrik Schulze and ... modulo 2 addition of more than tworandom bits and writeL ≈Ki=1sign(Li)· min(|L1|, ,|LK|). (3. 14) 3 Channel Coding 3. 1 General Principles 3. 1.1 The concept of channel codingChannel ... in the OFDM system DRM (Digital Radio Mondiale). The iterative decoding of a convolutionally codedQAM system with OFDM will be discussed in Subsection 4.5.2. 3. 1.5 Log-likelihood ratios and the...

Theory and applications of ofdm and cdma wideband wireless communications phần 4 ppt

... 0, 1, 2, 3, 4, 5, 6 is deﬁned by the addition table+ 12 345 61 2 345 602 345 6013 45 6012 4 5601235 6012 34 6 012 345 and the multiplication table12 345 6 246 1353625 14 415263531 642 6 543 21Note that ... duration that is matched to the channel and parallelize the given data streamin an appropriate way. Theory and Applications of OFDM and CDMA Henrik Schulze and Christian Lăuders 2005 John Wiley ... also suited to convince a practical engineer that the concept of OFDM should work. 4 OFDM 4. 1 General Principles 4. 1.1 The concept of multicarrier transmissionLet us consider a digital transmission...

Theory and applications of ofdm and cdma wideband wireless communications phần 5 ppsx

... 162 OFDM 0 50 100 150 200 250 300 350 400 450 50 0 50 –40–30–20(a)(b)–10010Normalized frequency fTPower spectrum (linear)0 50 100 150 200 250 300 350 400 450 50 0 50 –40–30–20–10010Normalized ... (b) and theamplitude (c) of an OFDM signal of average power one.–3 –2 .5 –2 –1 .5 –1 –0 .5 0 0 .5 1 1 .5 20.0010.0030.010.020. 05 0.100. 25 0 .50 0. 75 0.900. 95 0.980.990.9970.999Samples of ... where v is the vehicle speed and νmax=vcf0 OFDM 1670 0 .5 1 1 .5 2 2 .5 3 3 .5 4–20(a)(b)(c)2t/TS0 0 .5 1 1 .5 2 2 .5 3 3 .5 4t/TS0 0 .5 1 1 .5 2 2 .5 3 3 .5 4t/TSI(t) –202Q(t)0123AmplitudeFigure...

Theory and applications of ofdm and cdma wideband wireless communications phần 6 pot

... 2K = 15 36, L = 80 OFDM with 16- QAM and Rc= 0.5CE idealCE realFigure 4 .67 Simulation of a wideband OFDM system with 16- QAM for a moderately fast and frequency nonselective channel. OFDM 2410 ... function of Eb/N0for such a channel and 16- QAMtransmission with code rate Rc= 1/2 and a huge time and frequency interleaving over thebandwidth of K = 768 carriers and the time of I/K = 360 OFDM ... = 80 OFDM with 16- QAM and Rc= 0.5Figure 4.74 Simulation of narrowband OFDM for a slow and ﬂat channel. 240 OFDM The complex QAM symbols will be processed blockwise by an IFFT device of FFT...

Theory and applications of ofdm and cdma wideband wireless communications phần 7 ppsx

... multiplication of the data symbols by a spreading sequence of pseudoran-dom signs. These sequences are called pseudonoise (PN) sequences or code signals. We Theory and Applications of OFDM and CDMA Henrik ... deﬁnition of wideband is the same as that introduced in Chapter 4 for OFDM. Furthermore,it should not be confused with one transmission mode of UMTS, which is also often called Wideband CDMA. Its ... very serious candidate and, at the end of the project, an OFDM systemwas standardized in 1993 (see (EN300401 2001a) for a recent update of the standard). Anexhaustive treatment of the DAB system...

Theory and applications of ofdm and cdma wideband wireless communications phần 8 pot

... number of base stations involved in a soft handovershould be kept small. To illustrate this soft handover effort, Figure 5.23 shows the fraction of connections involved in a soft (or softer) handover ... difference of the local mean levels of both signals has been set to0, 3and6 dB.In Figure 5.22, the corresponding probability functions of the signal levels with and without soft handover are ... logs∈S0exp1σ2s†C†v−12s†Kss∈S1exp1σ2s†C†v−12s†Ks. (5.40) 3 28 CDMA from the union of Regions 2 and 3. For high values of Eb/N0, it comes closer and closerto the piecewise linear MLSE threshold depicted in Figure 5. 28. We note that...

Theory and applications of ofdm and cdma wideband wireless communications phần 9 pot

... Subsection 4.6.3 – use OFDM to handle data rates of up to 54 Mbit/s.More details on the IEEE 802.11 standard can be found, for example, in (O’Hara and Petrick 199 9). 350 CDMA Sincevl= h†lr ... usingpure CDMA and a time division duplex (TDD) mode using a combination of CDMA and TDMA as the multiple access scheme. The FDD mode is based on a proposal originallycalled the Wideband CDMA (WCDMA), ... capabilities.Between 199 5 and 199 8, the main focus for new releases of these standards was on creatingnew data services allowing higher rates and a packet switched mode. The increase of thedata rate...

Theory and applications of ofdm and cdma wideband wireless communications phần 10 docx

... INDEXNyquistbase, 9criterion, 10 pulse, 9 OFDM, 1, 145 OFDM and nonlinearities, 166symbol, 159 OFDM with convolutional coding, 208,213 OFDM with QAM, 213 OFDM with QPSK, 208Omni cell, 270Open-loop ... 384, 391Channel coding, 93, 245 Theory and Applications of OFDM and CDMA Henrik Schulze and Christian Lăuders 2005 John Wiley & Sons, LtdChannel coding for CDMA, 294Channel diversity, 192Channel ... (Holma and Toskala 2001)), CDMA was establishedas the dominating multiple access technology: systems like cdma2 000 and UMTS with the twotransmission modes Wideband CDMA and Time Division CDMA...

An investigation into Viet Bac High school 11th grade students and teachers' attitudes towards the applications of pairwork and groupwork in teaching and learni

... is the reality of teaching and learning speaking skill in Viet Bac high school? What are the attitudes of students and teachers towards pair and group work in a speaking lesson there? Whether ... the attitudes of teachers and 11th grade students at Viet Bac high school towards the application of pair and groupwork in teaching and learning speaking skills (ii) to examine the current ... FACULTY OF POST-GRADUATE STUDIES BẾ THỊ THU TRANG AN INVESTIGATION INTO VIET BAC HIGH SCHOOL 11TH GRADE STUDENTS AND TEACHERS’ ATTITUDES TOWARDS THE APPLICATIONS OF PAIRWORK AND GROUPWORK...

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