Download or read book Channel Estimation in Single Carrier Frequency Domain Equalization Space Division Multiple Access Systems written by Fayyaz Ahmad Siddiqui and published by . This book was released on 2008 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Decision feedback Equalization and Channel Estimation for Single carrier Frequency Division Multiple Access written by and published by . This book was released on 2011 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Semi Blind Carrier Frequency Offset Estimation and Channel Equalization written by Yufei Jiang and published by Springer. This book was released on 2015-12-01 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: This SpringerBrief investigates the performance of semi-blind independent component analysis (ICA) based equalization and carrier frequency offset estimation approaches (CFO) for a number of orthogonal frequency division multiplexing (OFDM) based wireless communication systems. It provides a comprehensive overview of the challenges of channel equalization and frequency synchronization for different wireless systems. The authors present the wireless communication channel and system models. Key existing CFO estimation methods are reviewed, along with a number of the training based and non-training based (blind) channel estimation methods. This is followed by a study of ICA and its applications to OFDM-based wireless communication systems. Later chapters provide a detailed description of recent research on semi-blind CFO estimation and ICA based equalization approaches for various wireless communication systems including multiple-input multiple-output (MIMO) OFDM and coordinated multipoint (CoMP) systems. Semi-blind CFO estimation and equalization structures provide a spectrum-efficient and high-performance solution for high speed wireless communications. This book is suitable for postgraduate students, researchers or professionals in the area of wireless communications.

Download or read book Channel Estimation and Equalization in MultiGigabit Systems written by Bernardo Martínez Blas and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In actual mobile radio systems, multipath conditions pose a problem, as the channel becomes frequency dependent. This point is especially critical in case of high frequency transmissions with very high data rate and high error performance, such as defined in the IEEE 802.15.3c which is an emerging 60-GHz standard supporting data rates of multi-giga bits per second (multi-Gbps) for short-range indoor applications. The deployment of such high speed wireless transmission has been very difficult throughout history mainly by two critical factors: the first one was the lack of wide enough spectrum and the second one is the high cost of high frequency circuits and devices. However, this trend is changing to the point that not too long ago, the substantial unlicensed spectrum became available at the millimeter-wave band of 60-GHz. Also, the advancement in technology drives the cost of 60-GHz circuits and devices much lower than in the past making possible its use for high definition audio and video wireless transmissions. In order to overcome the transmission channel issues, it is necessary to include a channel equalizer in the receiver, which must estimate the channel impulse response and make some operations to transform the frequency dependent channel to a flat channel. Nevertheless, the equalizer technology will depend on three different factors: first one the physical layer (PHY) technique under consideration for multi-Gbps Wireless Personal Area Network (WPAN) which basically could be orthogonal frequency division multiplexing (OFDM) or single-carrier frequency domain equalization (SC-FDE); second, the channel impulse response estimation carried out in order to determine the channel transfer function H(f), existing several methods to obtain an estimation; and third, the used equalization method and structure in order to reverse all distortions produced by the channel. This Master thesis has been carry out during an Erasmus program in the Technische Universitat of Braunchweig, Germany, and it is the first part of a whole European project for the study, analysis and deployment of the IEEE 802.15.3c standard for wireless communications with very high data rate and high error performance in the 60-GHz band. According to the instructions and requirements defined by professor Thomas Kürner which was in charge of this project, this thesis include: first, a theoretical study of all the different propagation effects which could affect a wireless communication channel in order to run not only the simulations presented in this thesis but also the future simulations; second, the development of a model in Matlab/Simulink that will be useful to carry out all the project simulations (taken into account the specifications collected in IEEE 802.15.3c standard); third, the results of the carried simulations for Single Carrier Channel estimation and equalization by using two different equalization methods in the frequency domain: Zero Forcing and Minimum Mean Square Error equalization. Taking this into account, the thesis is organized as follows. Section I is dedicated to the study of all the different propagation effects and problems which affects a wireless communication transmissions; In Section II, technologies and Physical Layer Modes are described attending the IEEE 802.15.3c in order to learn its different characteristics for the subsequent channel estimation; Section III is devoted to channel estimation and equalization methods description; estimation and equalization methods are selected in order to carry out the simulations in Section IV; finally, in Section V the developed system simulator as well as the obtained simulation results are presented after implementation of Zero Forcing and Minimum Mean Square Error equalization methods in Matlab/Simulink.

Download or read book Frequency domain Equalization of Single Carrier Transmissions Over Doubly Selective Channels written by Hong Liu and published by . This book was released on 2007 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Wireless communication systems targeting at broadband and mobile transmissions commonly face the challenge of fading channels that are both time and frequency selective. Therefore, design of effective equalization and estimation algorithms for such channels becomes a fundamental problem. Although multi-carrier transmissions demonstrate prominent potential to combat doubly selective fading, several factors may retard their applications, such as: high peak-to-average power ratio, sensitivity to phase noise, etc. Meanwhile, single-carrier transmission is a conventional approach and has important applications, such as HDTV broadcasting, underwater acoustic communication. In this dissertation, we focus on receiver design for single-carrier transmissions. Our goal is to design and develop a group of channel estimation and equalization algorithms in the frequency-domain, which enable high performance and low complexity reception of single-carrier transmissions through doubly selective channels. For single-carrier transmissions over moderately fast fading channels with long-delay spread, we present an improved iterative frequency-domain equalization (IFDE) algorithm based on soft-interference-cancellation (SIC) and propose a novel adaptive frequency-domain channel estimation (AFDCE) based on soft-input Kalman filter, where soft information feedback from the IFDE can be exploited in the channel estimator. Simulation results show that, compared to other existing schemes, the proposed scheme offers lower MSE in channel prediction, lower BER after decoding, and robustness to non-stationary channels. We extend the IFDE/AFDCE scheme to accommodate the application of digital television (DTV) signal reception. Compared with the traditional joint decision feedback equalization (DFE) /decoding plus frequency-domain least-mean-square (FDLMS) channel estimation approach, the proposed scheme achieves better performance at a fraction of the implementation cost. For very fast fading large-delay-spread channels, traditional FDE methods fail, because channel variation within a FFT block induces significant off-main-diagonal coefficients in the frequency domain. To conquer the problem, we apply Doppler channel shortening to shape the energy distribution of those coefficients and derive a pilot-aided MMSE estimator to estimate them for SIC. We also propose a novel IFDE by leveraging both the sparse structure of shortened channel and finite-alphabet property of transmitted symbols. Numerical results show that the proposed scheme has advantages over the well-known FIR-MMSE-DFE/RLS-CE scheme in both performance and complexity.

Download or read book Multi Carrier and Spread Spectrum Systems written by Khaled Fazel and published by John Wiley & Sons. This book was released on 2008-09-15 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technological progress in multi-carrier (MC) modulation led orthogonal frequency division multiplexing (OFDM) to become an important part of beyond 3G cellular mobile communication standards, including LTE and WiMAX. In addition, the flexibility offered by the spread spectrum (SS) and time division multiplexing (TDM) techniques motivated many researchers to investigate several MC combined multiple access schemes, such as MC-CDMA, OFDMA and MC-TDMA. These schemes benefit from the advantages of each sub-system and offer high flexibility, high spectral efficiency, simple detection strategies and narrow-band interference rejection capability. Multi-Carrier and Spread Spectrum Systems is one of the first books to describe and analyze the basic concepts of multi-carrier OFDM transmission and its combination with spread spectrum (MC-CDMA). The different architectures and detection strategies as well as baseband-related transceiver components are explained. This includes topics like FEC channel coding and decoding, modulation and demodulation (IFFT/FFT), digital I/Q-generation, time and frequency synchronisation, channel estimation, frequency domain equalization and RF aspects such as phase noise and non-linearity issues. Concrete examples of its applications for cellular mobile communication systems (B3G/4G) are given. Further derivatives of MC-SS (such as OFDMA, SS-MC-MA and DFT-spread OFDM) and their corresponding applications in the LTE, WiMAX, WLAN and DVB-RCT standards are detailed. Capacity and flexibility enhancements of multi-carrier OFDM systems by different MIMO diversity techniques such as space time/frequency coding (STC, SFC) and software defined radio concepts are also described. Written in a highly accessible manner this book provides a unique reference on the topics of multi-carrier and spread spectrum communications, assisting 4G engineers with their implementation. Fully updated new edition of successful text, including two new chapters on LTE and WiMAX Describes in detail new applications of OFDM in mobile communication standards Examines all multi-carrier spread spectrum schemes, with in-depth analysis, from theory to practice Introduces the essentials of important wireless standards based on multi-carrier/spread spectrum techniques.

Download or read book Channel Estimation and Equalization for Cooperative Communication written by Hakam Mheidat and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Efficient Schemes for Channel Estimation in Single Carrier Block Transmission with Frequency Domain Equalization written by and published by . This book was released on 2015 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pilot Assisted Channel Estimation for Multipath DS CDMA Systems written by Mansour Tahernezhadi and published by . This book was released on 2009-11 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of Channel Estimation for Mobile Communications written by Md. Masud Rana and published by LAP Lambert Academic Publishing. This book was released on 2012 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently, mobile communications have developed rapidly due to the endless demand for broadband multimedia access and wireless connection anywhere, and any time. To harvest the advantages of these enabling technologies maximally, both tremendous opportunities, and major challenges are current in the research of signal processing specially for channel estimation (CE). CE algorithms allow the receiver to approximate the impulse response of the channel and explain the behavior of the channel. The focus of this work is to investigate and evaluate the different CE techniques in a single carrier frequency division multiple access (SC-FDMA) system. Here we analyze new variable step size (VSS)-least mean squares (LMS) and normalized VSS (NLMS)-normalized LMS (NLMS) blind CE algorithm that can automatically adapts the optimum weighting coefficients to the channel condition. This time-varying step size method is updated at each iteration to minimize the sum of the squares of the prior estimation errors up to that current time point. In addition, this CE algorithm uses phase discriminating weighting scheme such that algorithm is reduces error owing to noise as well as decision error.

Download or read book A Pilot assisted Channel Estimation for Space time Block Coded Multipath DS CDMA Systems Using Frequency Domain Equalization written by Karthik Ananthula and published by . This book was released on 2007 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adaptive Channel Estimation for Multiple Input Multiple Output Frequency Domain Equalization written by and published by . This book was released on 2005 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper we investigate adaptive channel estimation for frequency domain equalization (FDE) in a single carrier (SC) multiple-input multiple-output (MIMO) system. Two types of channel estimation methods are proposed, assuming uncorrelated and correlated frequency bins. The FDE coefficients are computed using the channel estimates. It is shown that our proposed structures significantly outperform the adaptive FDE without channel estimation at high SNR. In particular, the proposed LMS-SCE FDE approaches the performance of FDE with perfect channel state information (CSI), and has a fast convergence speed and reasonably low complexity.

Download or read book Design of Channel Estimation and Equalization for OFDM Systems written by Ali Salah Mahdi and published by LAP Lambert Academic Publishing. This book was released on 2015-01-20 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal Frequency Division Multiplexing (OFDM) system is one of the multicarrier techniques which is robust against Inter-symbol-Interference, multipath fading and very easy to apply in transmitters by using inverse fast Fourier transform IFFT and at the receivers by using fast Fourier transform FFT. In a communication system, channel estimation is very important issue for the data detection. In coherent detection, one of the popular techniques is to use pilot tones as a reference signal in OFDM symbols. In the comb-type pilot tones insertion, pilot tones are inserted into each OFDM symbols, but inserting a large number of pilot tones will lead to channel capacity reduction or bandwidth expansion [1-2]. In this work, to overcome this transmission loss, a modified least square (ModLS) algorithm for fast time varying wireless channel at comb-type pilot arrangement in QAM signals for OFDM system is proposed. The simulation results obtained from the proposed algorithm showed a good performance in noisy wireless channels. In addition, it has been compared with least square (LS) algorithm in different signal to noise ratios and different channel tabs.

Download or read book Multi Carrier Spread Spectrum written by Khaled Fazel and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: The benefits and success of multi-carrier (MC) modulation on one side and the flexibility offered by the spread spectrum (SS) technique on the other side have motivated many researchers to investigate the combination of both techniques since 1993. This combination known as multi-carrier spread spectrum (MC-SS) benefits from the advantages of both systems and offers high flexibility, high spectral efficiency, simple detection strategies, narrow-band interference rejection capability, etc. The basic principle of this combination is straightforward: The spreading is performed as direct sequence spread spectrum (DS-SS) but instead of transmitting the chips over a single carrier, several sub-carriers are employed. The MC modulation and demodulation can easily be realized in the digital domain by performing IFFT and FFT operations. The separation of the users' signals can be performed in the code domain. MC-SS systems can perform the spreading in frequency direction, which allows for simple signal detection strategies. Since 1993, MC-SS has been deeply studied and new alternative solutions have been proposed. Meanwhile, deep system analysis and comparison with DS-CDMA have been performed that show the superiority of MC-CDMA.

Download or read book Orthogonal Frequency Division Multiple Access Fundamentals and Applications written by Tao Jiang and published by Auerbach Publications. This book was released on 2019-08-30 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt: Supported by the expert-level advice of pioneering researchers, Orthogonal Frequency Division Multiple Access Fundamentals and Applications provides a comprehensive and accessible introduction to the foundations and applications of one of the most promising access technologies for current and future wireless networks. It includes authoritative coverage of the history, fundamental principles, key techniques, and critical design issues of OFDM systems. Covering various techniques of effective resource management for OFDM/OFDMA-based wireless communication systems, this cutting-edge reference: Addresses open problems and supplies possible solutions Provides a concise overview of key techniques for adaptive modulation Investigates radio channel modeling in OFDMA-based wireless communication systems Details detection strategies of frequency-domain equalization for broadband communications Introduces a novel combination of OFDM and the orbital angular momentum of the electromagnetic field to improve performance Contains extensive treatment of adaptive MIMO beamforming suitable for multiuser access This valuable resource supplies readers with a macro-level understanding of OFDMA and its key issues, while providing a systematic manual for those whose work is directly related to practical OFDMA and other multiuser communication systems projects.

Download or read book SC FDMA for Mobile Communications written by Fathi E. Abd El-Samie and published by CRC Press. This book was released on 2016-04-19 with total page 372 pages. Available in PDF, EPUB and Kindle. Book excerpt: SC-FDMA for Mobile Communications examines Single-Carrier Frequency Division Multiple Access (SC-FDMA). Explaining this rapidly evolving system for mobile communications, it describes its advantages and limitations and outlines possible solutions for addressing its current limitations.The book explores the emerging trend of cooperative communicatio

Download or read book MIMO Processing for 4G and Beyond written by Mário Marques da Silva and published by CRC Press. This book was released on 2014-06-03 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt: MIMO Processing for 4G and Beyond: Fundamentals and Evolution offers a cutting-edge look at multiple-input multiple-output (MIMO) signal processing, namely its detection (in both time and frequency domains) and precoding. It examines its integration with OFDM, UWB, and CDMA, along with the impact of these combinations at the system level. Massive MIMO and network coding at the physical layer are very recent topics which are also addressed, and which are expected to play an important role in 5G systems. The book brings together contributing authors from first-class institutions who have been working in international research and development (R&D) projects and are highly cited in the MIMO field. These experts examine ongoing R&D activities in the field of MIMO systems and its associated signal processing that is expected to be employed in 4G and 5G systems. Covers the various wireless communication standards that make use of MIMO systems Explains the receiver processing associated with MIMO signal detection (including the case of massive MIMO systems) and presents the optimal precoding techniques Considers optimized MIMO schemes and processing for block transmission techniques, for orthogonal frequency division multiplexing (OFDM) transmission techniques, and for single carrier-frequency domain equalization Examines MIMO processing and optimization for wideband code division multiple access (WCDMA) Describes the ultra-wideband (UWB) transmission technique and the corresponding MIMO processing and optimizations Explains physical layer network coding techniques From basic receiver design to more advanced processing, the book covers the spectrum of topics associated with MIMO systems and MIMO processing. It provides a comprehensive description of MIMO fundamentals and theory that is ideal for anyone looking to sharpen their skills on the subject, such as corporate/industrial employees or graduate students. The book summarizes the most important enhancements related to the processing of MIMO systems for 4G systems, including its evolution and future trends. It also supplies a performance analysis of the various combinations of MIMO schemes for 4G systems to help you select the combination best suited for your particular needs.