Download or read book Multiple input Multiple output Orthogonal Frequency Division Multiplexing in Fast Fading Channels written by Sungsoo Kim and published by . This book was released on 2003 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multi User Orthogonal Frequency Division Multiplexing in Multipath Fast Frequency Selective Fading Using Multi Input Multi Output Antennas Based on Space Time Block Coding written by Hanieh Madadifar and published by . This book was released on 2006 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Orthogonal Frequency Division Multiplexing with Diversity for Future Wireless Systems written by Khoa N. Le and published by Bentham Science Publishers. This book was released on 2012 with total page 621 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The book examines several aspects of Orthogonal Frequency Division Multiplexing (OFDM) employing linear diversity techniques such as inter-carrier interference, bit error rate, peak to average power and inter-block interference. It should be a useful refe"
Download or read book Multi antenna OFDM Systems in the Presence of Phase Noise and Doubly selective Fading written by Yu Zhang and published by . This book was released on 2006 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal frequency division multiplexing (OFDM), which has been very attractive for future high rate wireless communications, is very robust to channel multipath fading effect while providing high transmission data rate with high spectral efficiency. Multiple antennas can be combined with OFDM to increase diversity gain and to improve spectral efficiency through spatial multiplexing and space-time coding (STC). This dissertation focuses on performance analysis and detection schemes of multi-antenna OFDM systems in the presence of phase noise and doubly-selective fading where channel is both time-selective and frequency-selective. In space-time coded OFDM (ST-OFDM), channel time variations cause not only intercarrier interference (ICI) among different subcarriers in one OFDM symbol, but also intertransmit-antenna interference (ITAI). We quantify the impact of time-selective fading on the performance of quasi-orthogonal ST-OFDM systems by deriving, via an analytical approach, the expressions of carrier-to-interference ratio (CIR) and signal-to-interference-plus-noise ratio (SINR). We also evaluate the performance of five different detection schemes and show that all these schemes suffer from an irreducible error floor. Multiple-input multiple-output (MIMO) antennas combined with OFDM are very attractive for high-data-rate communications. However, MIMO-OFDM systems are very vulnerable to time-selective fading. We apply frequency-domain correlative coding in MIMO-OFDM systems over doubly-selective fading channels and derive the analytical expression of CIR to demonstrate the effectiveness of correlative coding in mitigating ICI. When applied in fast fading channels, common ST-OFDM receivers usually suffer from an irreducible error floor. We apply frequency-domain correlative coding combined with a modified decision-feedback (DF) detection scheme with low complexity to effectively suppress the error floor of quasi-orthogonal ST-OFDM over fast fading channels. Similar to single-antenna OFDM, MIMO-OFDM suffers from significant performance degradation due to phase noise and time-selective fading. After characterizing the common phase error (CPE) caused by phase noise and ICI caused by phase noise as well as time-selective fading, we derive a minimum mean-squared error (MMSE)- based scheme to mitigate the effect of both phase noise and Doppler frequency shift. We also evaluate and compare the performance of various detection schemes combined with the proposed CPE mitigation scheme. Throughout the dissertation, theoretical performance analysis is always presented along with corroborating simulations.
Download or read book Multiplexing written by Somayeh Mohammady and published by BoD – Books on Demand. This book was released on 2019-09-04 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mobile communication has been a critical part of everyday life for the last 30 years. As the demand for wireless communications and higher data rates on these links continues its rapid growth, engineers, scientists, and researchers are required to advance the hardware and software needed to deliver systems for 5G, Massive multiple-input, multiple-output (MIMO), and optical backhaul networks. Now, more than ever before, the fundamental concept of multiplexing is at play. This book is a unique reference for understanding the concept of multiplexing. It provides comprehensive coverage of the practical applications of multiplexing to help the reader better understand its use in these systems. It is a great resource, especially for engineers working on digital signal processing, radio frequency (RF), antenna design, beamforming, and network designs. The book contains chapters on the following topics: • History of multiplexing and how it applies to current technologies; • Different types and applications of multiplexing; • Multiplexing techniques in wireless networks; • Multiple-Input, Multiple-Output Orthogonal Frequency-Division Multiplexing (MIMO-OFD); • Direct-Sequence Optical-Code Division Multiple-Access (DS-OCDMA); • Optically multiplexed systems
Download or read book Hardware Implementation of Multiple input Multiple output Transceiver for Wireless Communication written by Bing Han and published by . This book was released on 2014 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This dissertation proposes an efficient hardware implementation scheme for iterative multi-input multi-output orthogonal frequency-division multiplexing (MIMO-OFDM) transceiver. The transmitter incorporates linear precoder designed with instantaneous channel state information (CSI). The receiver implements MMSE-IC (minimum mean square error interference cancelation) detector, channel estimator, low-density parity-check (LDPC) decoder and other supporting modules. The proposed implementation uses QR decomposition (QRD) of complex-valued matrices with four co-ordinate rotation digital computer (CORDIC) cores and back substitution to achieve the best tradeoff between resource and throughput. The MIMO system is used in field test and the results indicate that the instantaneous CSI varies very fast in practices and the performance of linear precoder designed with instantaneous CSI is limited. Instead, statistic CSI had to be used This dissertation also proposes a higher-rank principle Kronecker model (PKM). That exploits the statistic CSI to simulate the fading channels. The PKM is constructed by decomposing the channel correlation matrices with the higher-order singular value decomposition (HOSVD) method. The proposed PKM-HOSVD model is validated by extensive field experiments conducted for 4-by-4 MIMO systems in both indoor and outdoor environments. The results confirm that the statistic CSI varies slowly and the PKM-HOSVD will be helpful in the design of linear precoders."--Abstract, page iv.
Download or read book Performance of 4x1 Space time Conjugate and Parallel Scheme in MIMO OFDM System written by Akhil Kumar Pathani and published by . This book was released on 2017 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Orthogonal Frequency Division Multiplexing (OFDM) in Space-Time (ST) coding has been in headlines in the field of communications over the [past] few years due to its flexibility with Multiple Input Multiple Output (MIMO) systems. Orthogonality among carriers is required for OFDM[,] but Carrier Frequency Offset (CFO) at the receiver and change in Doppler shift affect the orthogonality between carriers and lead to Inter Carrier Interference (ICI). Two path transmission schemes are developed for suppressing ICI in MIMO-OFDM systems. Out of many schemes, Parallel Cancellation (PC) and Conjugate Cancellation (CC) are combined with ST-MIMO OFDM to form Space-Time Conjugate and Parallel Cancellation (STCPC) MIMO-OFDM because these schemes provide transmit diversity and coding gain along with ICI mitigation. Simulation results of 4x1 STCPC-MIMO-OFDM with code rate 1 provides excellent Bit Error Rate (BER) compared to conventional 4x1 ST-MIMO-OFDM with different code rates of 0.5 and 1. This scheme also provides better BER performance with lower error floor in fast and slow frequency selective fading channels.
Download or read book Channel Modelling and Estimation in Multiple input Multiple output Orthogonal Frequency Division Multiplexing Wireless Communication Systems written by Mohammed Abdo Saeed Hezam and published by . This book was released on 2008 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Orthogonal Frequency Division Multiplexing for Wireless Communications written by Ye Geoffrey Li and published by Springer Science & Business Media. This book was released on 2006-05-31 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Orthogonal Frequency Division Multiplexing for Wireless Communications is an edited volume with contributions by leading authorities in the subject of OFDM. Its coverage consists of principles, important wireless topics (e.g. Synchronization, channel estimation, etc.) and techniques. Included is information for advancing wireless communication in a multipath environment with an emphasis on implementation of OFDM in base stations. Orthogonal Frequency Division Multiplexing for Wireless Communications provides a comprehensive introduction of the theory and practice of OFDM. To facilitate the readers, extensive subject indices and references are given at the end of the book. Even though each chapter is written by different experts, symbols and notations in all chapters of the book are consistent.
Download or read book Superimposed Training Aided Channel Estimation for Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing Systems Over High Mobility Environment written by Han Zhang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Superimposed Training Aided Channel Estimation for Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing Systems Over High Mobility Environment written by Han Zhang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Superimposed Training-Aided Channel Estimation for Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing Systems over High-Mobility Environment.
Download or read book Performance of 2x1 Space frequency Orthogonal Frequency Division Multiplexing with Discrete Wavelet Transform as Precoder written by Nilam R. Hargude and published by . This book was released on 2018 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Orthogonal Frequency Division Multiplexing (OFDM) is the integral part of many wireless and telecommunication standards. 4G LTE communication systems extensively use OFDM as their dominant interface. In wireless systems, OFDM splits the signal into channel and reduces crosstalk. In this thesis, a Space-Frequency (SF) processing is employed with Orthogonal Frequency Division Multiplexing (OFDM) to transform frequency selective fading channels into multiple flat fading sub-channels. Also, Discrete Wavelet Transform (DWT) is used in conjunction with Fast Fourier Transform (FFT) to improve the performance of SF-OFDM. This thesis passes data through a daubechies2 DWT precoder then divides the input data stream into even and odd inputs and passes it through the SF encoder and applies encoded output to the two transmitter systems. At the receiver end, the system estimates the Bit Error Rate (BER) using a one-receiver system. The BER is estimated using the output obtained at the receiver and then combining the odd and even parts to receive a better BER as compared to the 2x1 (2 transmitters, 1 receiver) SF-OFDM system. Simulation results show that the BER for a 2x1 SF-OFDM with precoder system are significantly improved over a 2x1 SF-OFDM system with TU channel in a COST207 model.
Download or read book Performance of Symmetrically and Asymmetrically Mapped 4X1 Space time frequency Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing System written by Naila Mariam Ghori and published by . This book was released on 2018 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: In wireless communication systems, diversity schemes improve the message reliability and help combat fading. Thus, by exploiting diversity schemes like Space, Time, and Frequency, Space-Time-Frequency codes are generated. These Space-Time-Frequency Block Codes (STFBC) are a combination of Space-Time Block Codes (STBC) and Space-Frequency Block Codes (SFBC). In these Space-Time- Frequency codes, channel codes use time diversity and frequency diversity followed by an orthogonal design which provides spatial diversity. The frequency diversity is applied first and then the time diversity to form the Space-Time-Frequency code. The performance of 4X1 Space-Time Block Codes (STBC), 4X1 Space-Frequency Block Codes (SFBC), and 4X1 Space-Time-Frequency Block Codes (STFBC) for 4G conditions are evaluated. Simulation results show that Space-Time-Frequency Block Codes (STFBC) are a good compromise in terms of performance and delay. For Space-Time-Frequency Block Codes (STFBC) an asymmetric mapping technique is introduced and the simulation of 4X1 asymmetrically mapped Space-Time-Frequency Block Codes provided a better Bit-Error-Rate (BER) compared to the 4X1 symmetrically mapped Space-Time-Frequency Block Codes. Simulations are performed in MATLAB for Jakes spectrum model and also for COST207 model.
Download or read book Adaptive Space frequency Coding for Multiple input and Multiple output Orthogonal Frequency Division Multiplexing Systems written by Antonios D. Valkanas and published by . This book was released on 2004 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Computational Intelligence and Sustainable Systems written by H. Anandakumar and published by Springer. This book was released on 2018-12-14 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book features research related to computational intelligence and energy and thermal aware management of computing resources. The authors publish original and timely research in current areas of power, energy, temperature, and environmental engineering as and advances in computational intelligence that are benefiting the fields. Topics include signal processing architectures, algorithms, and applications; biomedical informatics and computation; artificial intelligence and machine learning; green technologies in information; and more. The book includes contributions from a wide range of researchers, academicians, and industry professionals. The book is made up both of extended papers presented at the International Conference on Intelligent Computing and Sustainable System (ICICSS 2018), September 20-21, 2018, and other accepted papers on R&D and original research work related to the practice and theory of technologies to enable and support Intelligent Computing applications.
Download or read book Orthogonal Frequency Division Multiplexing Based Medium Access Under Rate Constraints written by Thomas Deckert and published by Jörg Vogt Verlag. This book was released on 2007 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Intelligent Multi Modal Data Processing written by Soham Sarkar and published by John Wiley & Sons. This book was released on 2021-04-06 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive review of the most recent applications of intelligent multi-modal data processing Intelligent Multi-Modal Data Processing contains a review of the most recent applications of data processing. The Editors and contributors – noted experts on the topic – offer a review of the new and challenging areas of multimedia data processing as well as state-of-the-art algorithms to solve the problems in an intelligent manner. The text provides a clear understanding of the real-life implementation of different statistical theories and explains how to implement various statistical theories. Intelligent Multi-Modal Data Processing is an authoritative guide for developing innovative research ideas for interdisciplinary research practices. Designed as a practical resource, the book contains tables to compare statistical analysis results of a novel technique to that of the state-of-the-art techniques and illustrations in the form of algorithms to establish a pre-processing and/or post-processing technique for model building. The book also contains images that show the efficiency of the algorithm on standard data set. This important book: Includes an in-depth analysis of the state-of-the-art applications of signal and data processing Contains contributions from noted experts in the field Offers information on hybrid differential evolution for optimal multilevel image thresholding Presents a fuzzy decision based multi-objective evolutionary method for video summarisation Written for students of technology and management, computer scientists and professionals in information technology, Intelligent Multi-Modal Data Processing brings together in one volume the range of multi-modal data processing.
