theory of spread spectrum communications
Tài liệu PRINCIPLES OF SPREAD-SPECTRUM COMMUNICATION SYSTEMS ppt
... summations to we obtain The information-weight spectrum or distribution is defined as In terms of this distribution, (1-110) becomes PRINCIPLES OF SPREAD- SPECTRUM COMMUNICATION SYSTEMS 32 CHAPTER ... number of sequences that can be obtained by changing any of the nonzero symbols to zeros is where if For a specified value of it is necessary that to ensure a sequence of weight The number of sequences that ... codewords of the total weight of all the symbols in a fixed position is the same regardless of the position and is equal to The total weight of all the information symbols in is Therefore, Optimal soft-decision...
Ngày tải lên: 20/01/2014, 06:20
Theory of stochastic local area channel modeling for wireless communications
... domain, X(f )issimplyacopyofthe spectrum ˜ X(f) shifted to a center frequency of f =+f c and a mirror copy of ˜ X(f)shifted to a center frequency of f = −f c . The operation of modulation can be defined ... SummaryofAngleSpectrumConcepts 124 5.2 FadingRateVariance 127 5.2.1 DefinitionofaRateVariance 127 5.2.2 Fundamental Spectral Spread Theorem . . . 129 5.3 MultipathShapeFactors 130 5.3.1 DefinitionofShapeFactors ... ProperLimitingBehavior 117 4.B.4 PreservationoftheSecondMoment 117 5 The Angle Spectrum 118 5.1 AngleSpectrumConcepts 119 5.1.1 DefinitionoftheAngleSpectrum 119 5.1.2 MappingAnglestoWavenumbers...
Ngày tải lên: 20/11/2012, 11:36
Báo cáo hóa học: " Research Article Resource Allocation with Adaptive Spread Spectrum OFDM Using 2D Spreading for Power Line Communications" doc
Ngày tải lên: 22/06/2014, 19:20
Trải phổ SPREAD SPECTRUM
... dùng cho thông tin vệ tinh trong CDMA. Trải phổ nhảy tần Frequency Hopping Spread Spectrum Frequency Hopping Spread Spectrum (FHSS) Được phát minh bởi nữ diễn viên Hollywood Hedy Lamarr, ... thu và máy phát đều có bộ tạo mã PN gồm k chíp mã tương ứng với 1 từ tần số Direct Sequence Spread Spectrum Transmitter Vídụ CDMA Các ưu nhược điểm FHSS Ưu điểm : Giảm fading đa đường do ... phát hiện Nhảy tần nhanh (Fast FHSS) (M=4, k=2) Điều chế và giải điều chế Direct Sequence Spread Spectrum Transmitter Trải phổ nhảy tần Dẫy PN dùng để điều khiển (xác định) mẫu nhảy. Tốc...
Ngày tải lên: 13/09/2012, 11:16
Lecture 4 - Spread Spectrum Technologies
... 43 OFDM February 2005 Copyright 2005 All Rights Reserved 3 Spread Spectrum ● Spread spectrum is a communication technique that spreads a narrowband communication signal over a wide range of ... which employs OFDM in the 2.4 GHz range February 2005 Copyright 2005 All Rights Reserved 6 Spread Spectrum Use ● In the 1980s FCC implemented a set of rules making Spread Spectrum available ... the imaginary or quadrature axis of the complex plane. February 2005 Copyright 2005 All Rights Reserved 4 Narrowband vs Spread Spectrum Frequency Power Spread Spectrum (Low Peak Power) Narrowband (High...
Ngày tải lên: 13/09/2012, 11:16
The theory of financial intermediation: An essay on what it does (not) explain
... which are seen as a form of market imperfection. The mainstream theory of the firm evolved under the paradigm of the agency theory and the transaction costs theory as a theory of economic organization rather ... amendment of the existing theory of financial intermediation. The structure of this paper is as follows. First, we introduce the foundations of the modern literature of financial intermediation theory. ... review the doctrines of the theory of financial intermediation. 2 These are specifications, relevant to the financial services industry, of the agency theory, and the theory of imperfect or asymmetric...
Ngày tải lên: 24/10/2012, 09:11
Circuit theory of finance and the role of incentives in financial sector reform
... efficiently, the reputational capital of an agent must equal the present value of the stream of future profits, or franchise value, of her business. The concept of reputational capital is meaningful ... Structural implications of CTF Circuit theory of finance (CTF) bears important implications in terms of financial market structure, microeconomic imbalances, and the role of saving for economic ... on the basis of verifiable and tested information. Information providers might be either profit or non-profit outfits. Providers of customized information might operate for a profit and sell...
Ngày tải lên: 24/10/2012, 09:33
Multi-Carrier and Spread Spectrum Systems
... multi-carrier, spread spectrum and multi-carrier spread spectrum systems. We hope that this book will contribute to a better understanding of the principles of multi-carrier and spread spectrum and ... fundamentals of today’s wireless communications. First a detailed description of the radio channel and its modeling are presented, followed by the introduction of the principle of OFDM multi-carrier ... is essential for a better understanding of the idea behind the combination of OFDM with the spread spectrum technique, which is briefly introduced in the last part of this chapter. 1.1 Radio Channel...
Ngày tải lên: 02/03/2013, 16:58
TEACHING PRONUNCIATION TO THE FIRST YEAR STUDENTS AT THE UNIVERSITY OF TRANSPORT AND COMMUNICATIONS a CASE STUDY
Ngày tải lên: 07/09/2013, 13:45
Complexity Theory of Transforms in Signal Processing
... behavior of the number of multiplications is also quadratic. Convolution algebras are derived from algebras of polynomials. Given a polynomial P (u) of degree D, one can define an algebra of dimension ... Introduction Complexity theory of computation attempts to determine how “inherently” difficult are certain tasks. For example, how inherently complex is the task of computing an inner product of two vectors of length ... original proof); the reference I like best is Adrian Albert’s book [1]. The theorem asserts that the tensor product of fields is isomorphic to a direct sum of fields, and the proof of the theorem...
Ngày tải lên: 25/10/2013, 02:15
Theory of rapid granular flows Isaac Goldhirsch
... number of collisions per particle (a measure of time), given by τ ≡ t 0 T 1/2 (t ) dt . The use of this measure of time renders the equations of motion linear. The three eigenvalues of this ... of the linearised Boltzmann equation, at each order in the expansion. Since the solution of equations of the type of Eq. (12.22) is determined up to the addition of an arbitrary combination of ... sheared system is of a much higher granular temperature than that expected on the basis of steady-state solutions of the corresponding hydrodynamic equations. In this case the 208 Theory of rapid granular...
Ngày tải lên: 01/11/2013, 08:20
Tài liệu Theory of Inventive Problem Solving pdf
... into a theory of inventive problem solving which he named TRIZ. 3.0 TRIZ: The Theory of Inventive Problem Solving There are a number of laws in the theory of TRIZ. One of them is the Law of Increasing ... Xerox Corporation 7.0 TRIZ Software Because TRIZ is built on a database of hundreds of thousands of patents, principles, operators, contradictions, etc. use of software helps engineers with ... nonmoving object 3. Length of moving object 4. Length of nonmoving object 5. Area of moving object 6. Area of nonmoving object 7. Volume of moving object 8. Volume of nonmoving object 9. Speed...
Ngày tải lên: 10/12/2013, 03:15
Tài liệu Introduction to Communication Systems, The Theory of Probability ppt
... gr qrw h{lvw Wkh sk|vlfdo phfkdqlvpv gulylqj wkh sureohp duh vr frpsolfdwhg wkdw wkh gluhfw fdofxodwlrq ri wkh sureohp lv qrw ihdvleoh Wkhuh h{lvwv vrph edvlf lqghwhuplqdf| lq wkh sk|vlfdo...
Ngày tải lên: 12/12/2013, 04:15
Tài liệu Spread Spectrum (SS) pptx
... use of OVSF codes is thus a key factor in the high degree of service flexibility of the W- CDMA air interface. Let C N be a matrix of size NxN and denote the set of N binary spreading codes of ... requiring spread spectrum modulation: DSSS (Direct Sequence Spread Spectrum) and FHSS (Frequency Hopping Spread Spectrum) . Only the RF transmission has significant presence in the market. 1Mbps Spreading d t pn t DBPSK 11 ... Sint-Katelijne-Waver Belgium www.denayer.be Spread Spectrum (SS) applications ir. J. Meel jme@denayer.wenk.be Studiedag Spread Spectrum 6 okt. ’99 In the period of nov. 1997 - nov. 1999 a Spread Spectrum project was...
Ngày tải lên: 13/12/2013, 00:15
Tài liệu The General Theory of Employment, Interest, and Money docx
... EFFICIENCY OF CAPITAL 12. THE STATE OF LONG-TERM EXPECTATION 13. THE GENERAL THEORY OF THE RATE OF INTEREST 14. THE CLASSICAL THEORY OF THE RATE OF INTEREST o APPENDIX ON THE RATE OF INTEREST ... advantages of private and national thrift, the traditional attitude towards the rate of interest, the classical theory of unemployment, the quantity theory of money, the unqualified advantages of laissez-faire ... and of the trade cycle. Another feature, especially characteristic of this book, is the theory of the rate of interest. In recent times it has been held by many economists that the rate of current...
Ngày tải lên: 15/12/2013, 21:15
Challenge your thinking on theory of constraints (toc) accounting (e schragenheim)
Ngày tải lên: 17/12/2013, 15:18