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Book Techniques for Peak Power Reduction in OFDM Systems

Download or read book Techniques for Peak Power Reduction in OFDM Systems written by and published by . This book was released on 2004 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A Study on the Tone Reservation Technique for Peak to Average Power Ratio Reduction in OFDM Systems

Download or read book A Study on the Tone Reservation Technique for Peak to Average Power Ratio Reduction in OFDM Systems written by Umer Ijaz Butt and published by Universal-Publishers. This book was released on 2010-08-27 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Advances in Computing and Information Technology

Download or read book Advances in Computing and Information Technology written by Natarajan Meghanathan and published by Springer Science & Business Media. This book was released on 2012-06-30 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt: The international conference on Advances in Computing and Information technology (ACITY 2012) provides an excellent international forum for both academics and professionals for sharing knowledge and results in theory, methodology and applications of Computer Science and Information Technology. The Second International Conference on Advances in Computing and Information technology (ACITY 2012), held in Chennai, India, during July 13-15, 2012, covered a number of topics in all major fields of Computer Science and Information Technology including: networking and communications, network security and applications, web and internet computing, ubiquitous computing, algorithms, bioinformatics, digital image processing and pattern recognition, artificial intelligence, soft computing and applications. Upon a strength review process, a number of high-quality, presenting not only innovative ideas but also a founded evaluation and a strong argumentation of the same, were selected and collected in the present proceedings, that is composed of three different volumes.

Book Peak Power Control in Multicarrier Communications

Download or read book Peak Power Control in Multicarrier Communications written by Simon Litsyn and published by Cambridge University Press. This book was released on 2007-01-04 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Peak signal power is an important factor in the implementation of multicarrier (MC) modulation schemes, like OFDM, in wireless and wireline communication systems. This 2007 book describes tools necessary for analyzing and controlling the peak-to-average power ratio in MC systems, and how these techniques are applied in practical designs. The author starts with an overview of multicarrier signals and basic tools and algorithms, before discussing properties of MC signals in detail: discrete and continuous maxima; statistical distribution of peak power; codes with constant peak-to-average power ratio are all covered, concluding with methods to decrease peak power in MC systems. Current knowledge, problems, methods and definitions are summarized using rigorous mathematics, with an overview of the tools for the engineer. The book is aimed at graduate students and researchers in electrical engineering, computer science and applied mathematics, and practitioners in the telecommunications industry.

Book Fast Peak power Reduction for MIMO OFDM Systems with Diversity

Download or read book Fast Peak power Reduction for MIMO OFDM Systems with Diversity written by Theodoros Tsiligkaridis and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A robust peak-power reduction technique called active constellation extension (ACE) reduces the peak-to-average power ratio (PAPR) of single-input single-output (SISO) orthogonal frequency-division modulated (OFDM) signals by extending the outer constellation points in a way that minimizes the PAPR of an OFDM transmit signal, without reducing the bandwidth or increasing bit error rate (BER). Recent work includes extensions of the concept of ACE using a modi ed smart gradient-project algorithm for MIMO-OFDM systems. We extend the e cient ACE smart gradient-project (SGP) method to space-time block coded (STBC), space-frequency block coded (SFBC) and V-BLAST OFDM systems. The proposed peak-power reduction method can be applied to any space-time-frequency (STF) block code, and its performance is bounded by the code structure. Simulations show PAPR reduction gains of 4.19 and 3.57 dB under QPSK for Alamouti STBC and SFBC, respectively. In addition, we extend the e cient ACE-SGP method to rotated constellations for SISO-OFDM systems, an alternative method recently invented for providing diversity. Simulation results show approximately 3.46 dB and 2.08 dB of PAPR reduction for QPSK and 16-QAM original constellations, respectively, for 256 subcarriers. Results also show that 4.29 dB and 3.41 dB of PAR reduction are obtained for QPSK and 16-QAM original constellations, respectively, for 1024 subcarriers. Furthermore, we show how the PAPR reduction method known as tone injection can be a very practical transmission scheme for coded-OFDM systems, with a slight compromise of the BER performance. This is accomplished by developing e cient, near-optimal, convolutional and LDPC decoders for the extended non-bijective constellations introduced by tone injection. Simulation results for convolutional and LDPC coded-OFDM systems show BER performance comparable to conventional coded OFDM with greatly reduced PAPR. Furthermore, results show that the PAPR performance obtained is very close to the 64-QAM single-carrier peak-power performance. So, the peak-power problem is solved for large constellations.

Book New Peak to average Power Ratio Reduction Schemes for OFDM Systems

Download or read book New Peak to average Power Ratio Reduction Schemes for OFDM Systems written by Peng Liu and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is known that the orthogonal frequency division multiplexing (OFDM) modulation is very suitable for high-speed wireless transmission systems due to its bandwidth efficiency and ability in coping with multipath fading. However, the large peak-to-average power ratio (PAPR) of an OFDM signal limits the application of OFDM to a certain degree. The research focus of this thesis is on the study of some new PAPR reduction schemes for OFDM systems. In the first part of the thesis, we investigate the peak windowing method, the clipping method, and a combination of the two techniques with an emphasis on the performance assessment of the transmitted OFDM signal using the combination scheme. We start with the review of the two typical signal distortion techniques and point out their advantages and shortcomings. We then propose a combination scheme for the two techniques in order to overcome their drawbacks. In the proposed combination scheme, a weighting function is used to remove instantaneous signal peaks and then a hard-limiting is utilized for the reduction of the overall peak powers. A modified IDFT interpolation is developed and employed in the combination scheme to improve the interpolation precision of the time-domain OFDM signal. (Abstract shortened by UMI.).

Book Peak to Average Power Ratio Reduction in OFDM Systems

Download or read book Peak to Average Power Ratio Reduction in OFDM Systems written by Anusha Chacko and published by LAP Lambert Academic Publishing. This book was released on 2015-04-17 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal Frequency Division Multiplexing (OFDM) is a promising technology in wireless communication. High Peak-to-Average Power Ratio (PAPR) is one of the challenging issues of OFDM systems. High PAPR forces the High Power Amplifier (HPA) to operate in its linear region with wide dynamic range, where the power efficiency is very poor. This book gives an overview of different PAPR reduction techniques. And deals in detail with the efficient use of Selected Mapping (SLM) and Partial Transmit Sequence (PTS)technique to reduce high PAPR in OFDM systems.

Book Peak to average Power Ratio Reduction Techniques in OFDM Systems

Download or read book Peak to average Power Ratio Reduction Techniques in OFDM Systems written by and published by . This book was released on 2010 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book IFFT based Techniques for Peak Power Reduction in OFDM Communication Systems

Download or read book IFFT based Techniques for Peak Power Reduction in OFDM Communication Systems written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal frequency division multiplexing (OFDM) is a multicarrier transmission technique which provides efficient bandwidth utilization and robustness against time dispersive channels. A major problem in the RF portion of a multicarrier transmitter is Gaussian-like time-domain signals with relatively high peak-to-average power ratios (PAPRs). These peaks can lead to saturation in the power amplifier (PA) which in turn distorts the signal and reduces the PA efficiency. To address this problem, numerous techniques have appeared in the literature based on signal and/or data modification. In the class of distortionless techniques, partial transmit sequences (PTS), selective mapping (SLM), and tone reservation (TR) have received a great deal of attention as they are proven techniques that achieve significant PAPR reduction. However, high computational complexity is a problem in practical systems. In PTS and SLM, this complexity arises from the computation of multiple inverse fast Fourier transforms (IFFTs), resulting in a complexity proportional to the number of PTS subblocks or SLM sequences. TR has also a high computational complexity related to the computation of the IFFT as it must search for the optimal subsets of reserved subcarriers and generate the peak reduction signal. In addition, most research in the direction of analyzing and improving the above techniques has employed direct computation of the inverse discrete Fourier transform (IDFT), which is not practical for implementation. This thesis focuses on the development and performance analysis of the major distortionless techniques in conjunction with the common IFFT algorithms to reduce the peak-to-power average (PAPR) of the original OFDM signal at the transmitter side. The structure of the IFFT common algorithms is used to propose a class of IFFT-based PAPR reduction techniques to reduce the computational complexity and improve PAPR performance. For IFFT based PTS, two techniques are proposed. A low compl.

Book Peak to Average Power Reduction for Multi antenna of OFDM Systems

Download or read book Peak to Average Power Reduction for Multi antenna of OFDM Systems written by Madhan Jaganthan and published by . This book was released on 2008 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Multicarrier Modulation with Low PAR

Download or read book Multicarrier Modulation with Low PAR written by Jose Tellado and published by Springer Science & Business Media. This book was released on 2005-12-11 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multicarrier Modulation with Low PAR: Applications to DSL and Wireless provides the first comprehensive formulation of the PAR problem for multicarrier modulation and proposes three new methods for PAR reduction. The information in this book will be vital to practicing engineers, industrial researchers, scientists, graduate and postgraduate researchers, and others working in multicarrier transmission and communication theory. Multicarrier Modulation with Low PAR: Applications to DSL and Wireless serves as a valuable reference to both design engineers and communications theorists, and can also be used for advanced courses on the subject.

Book Selective Mapping technique for PAPR reduction in LTE OFDM Systems

Download or read book Selective Mapping technique for PAPR reduction in LTE OFDM Systems written by Neelam Dewangan and published by GRIN Verlag. This book was released on 2012-11-22 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Master's Thesis from the year 2012 in the subject Engineering - Communication Technology, grade: none, , course: M.Tech, language: English, abstract: As a promising technique, OFDM has been widely used in emerging broadband communication systems, such as digital audio broadcasting (DAB), high-definition television (HDTV), wireless local area network (IEEE 802.11a and HIPERLAN/2). However, as the OFDM signals are the sum of signals with random amplitude and phase, they are likely to have large PAPR that requires a linear high-power- amplifier (HPA) with an extremely high dynamic range, which is expensive and inefficient. Furthermore, any amplifier nonlinearity causes intermodulation products resulting in unwanted out-of-band power. A number of approaches have been proposed to deal with the PAPR problem, including clipping, clipping-and-filtering (CF), coding, companding transform, active constellation extension (ACE), selected mapping (SLM), partial transmit sequence (PTS), and so on. This thesis proposes an improvement in Selected Mapping technique and Simulation results are compared to existing techniques namely Exponential Companding Transform, Repeated Clipping and Filtering and Adaptive Active Constellation Extension. The improvements which are proposed in classical Selective Mapping technique satisfies the PAPR Reduction criteria with reducing the computational complexity. Also this new scheme has an important advantage of avoiding the extra bits along with the transmitted OFDM signal .This scheme can also be applied to the multiple transmitting antenna cases.

Book Optimization Techniques in Engineering

Download or read book Optimization Techniques in Engineering written by Anita Khosla and published by John Wiley & Sons. This book was released on 2023-04-26 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: OPTIMIZATION TECHNIQUES IN ENGINEERING The book describes the basic components of an optimization problem along with the formulation of design problems as mathematical programming problems using an objective function that expresses the main aim of the model, and how it is to be either minimized or maximized; subsequently, the concept of optimization and its relevance towards an optimal solution in engineering applications, is explained. This book aims to present some of the recent developments in the area of optimization theory, methods, and applications in engineering. It focuses on the metaphor of the inspired system and how to configure and apply the various algorithms. The book comprises 30 chapters and is organized into two parts: Part I — Soft Computing and Evolutionary-Based Optimization; and Part II — Decision Science and Simulation-Based Optimization, which contains application-based chapters. Readers and users will find in the book: An overview and brief background of optimization methods which are used very popularly in almost all applications of science, engineering, technology, and mathematics; An in-depth treatment of contributions to optimal learning and optimizing engineering systems; Maps out the relations between optimization and other mathematical topics and disciplines; A problem-solving approach and a large number of illustrative examples, leading to a step-by-step formulation and solving of optimization problems. Audience Researchers, industry professionals, academicians, and doctoral scholars in major domains of engineering, production, thermal, electrical, industrial, materials, design, computer engineering, and natural sciences. The book is also suitable for researchers and postgraduate students in mathematics, applied mathematics, and industrial mathematics.