Ofdm Based Relay Systems for Future Wireless Communications

Download Ofdm Based Relay Systems for Future Wireless Communications PDF Online Free

Author :
Release : 2022-09-01
Genre : Science
Kind :
Book Rating : 008/5 ( reviews)

Ofdm Based Relay Systems for Future Wireless Communications - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Ofdm Based Relay Systems for Future Wireless Communications write by Milica Pejanovic-Djurisic. This book was released on 2022-09-01. Ofdm Based Relay Systems for Future Wireless Communications available in PDF, EPUB and Kindle. Relay systems have become a subject of intensive research interest over the recent years, as it is recognized that they can improve performances and extend the coverage area of wireless communication systems. Special attention has been dedicated to them since the proposal appeared for their implementation in mobile cellular systems. Numerous researches conducted after that proposal have enabled incorporation of OFDM based relay systems in both accepted standards for IMT-Advanced systems. Nowadays, researches are ongoing with the aim to define new solutions for performance improvement of the standardized OFDM relay systems for cellular networks and one of the interesting solutions is implementation of subcarrier permutation (SCP) at the relay (R) station.The book OFDM based relay systems for future wireless communications presents a comprehensive research results in analyzing behavior and performance of the OFDM based relay systems with SCP. Dual-hop relay scenario with three communication terminals, and no direct link between the source (S) and the destination (D) has been analyzed, as it is compliant with the accepted solutions for IMT-Advanced systems. The book includes performance analysis and performance comparison of OFDM based:• amplify-and-forward (AF) relay systems with fixed gain (FG),• amplify-and-forward (AF) relay systems with variable gain (VG),• decode-and-forward (DF) relay systems,each including two SCP schemes, known to maximize the system capacity and/or improve the bit error rate (BER) performances. Performance comparisons have enabled definition of optimal solutions for the future wireless communication systems in a given conditions, and for the given optimality criteria. OFDM based relay systems for future wireless communications contains recent research results in this area and is ideal for the academic staff and master/research students in area of mobile communication systems, as well as for the personnel in communication industry.

Ofdm Based Relay Systems for Future Wireless Communications

Download Ofdm Based Relay Systems for Future Wireless Communications PDF Online Free

Author :
Release : 2022-09-01
Genre : Technology & Engineering
Kind :
Book Rating : 163/5 ( reviews)

Ofdm Based Relay Systems for Future Wireless Communications - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Ofdm Based Relay Systems for Future Wireless Communications write by Milica Pejanovic-Djurisic. This book was released on 2022-09-01. Ofdm Based Relay Systems for Future Wireless Communications available in PDF, EPUB and Kindle. Relay systems have become a subject of intensive research interest over the recent years, as it is recognized that they can improve performances and extend the coverage area of wireless communication systems. Special attention has been dedicated to them since the proposal appeared for their implementation in mobile cellular systems. Numerous researches conducted after that proposal have enabled incorporation of OFDM based relay systems in both accepted standards for IMT-Advanced systems. Nowadays, researches are ongoing with the aim to define new solutions for performance improvement of the standardized OFDM relay systems for cellular networks and one of the interesting solutions is implementation of subcarrier permutation (SCP) at the relay (R) station.The book OFDM based relay systems for future wireless communications presents a comprehensive research results in analyzing behavior and performance of the OFDM based relay systems with SCP. Dual-hop relay scenario with three communication terminals, and no direct link between the source (S) and the destination (D) has been analyzed, as it is compliant with the accepted solutions for IMT-Advanced systems. The book includes performance analysis and performance comparison of OFDM based:• amplify-and-forward (AF) relay systems with fixed gain (FG),• amplify-and-forward (AF) relay systems with variable gain (VG),• decode-and-forward (DF) relay systems,each including two SCP schemes, known to maximize the system capacity and/or improve the bit error rate (BER) performances. Performance comparisons have enabled definition of optimal solutions for the future wireless communication systems in a given conditions, and for the given optimality criteria. OFDM based relay systems for future wireless communications contains recent research results in this area and is ideal for the academic staff and master/research students in area of mobile communication systems, as well as for the personnel in communication industry.

Full-Duplex Communications for Future Wireless Networks

Download Full-Duplex Communications for Future Wireless Networks PDF Online Free

Author :
Release : 2020-04-21
Genre : Computers
Kind :
Book Rating : 698/5 ( reviews)

Full-Duplex Communications for Future Wireless Networks - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Full-Duplex Communications for Future Wireless Networks write by Hirley Alves. This book was released on 2020-04-21. Full-Duplex Communications for Future Wireless Networks available in PDF, EPUB and Kindle. This book focuses on the multidisciplinary state-of-the-art of full-duplex wireless communications and applications. Moreover, this book contributes with an overview of the fundamentals of full-duplex communications, and introduces the most recent advances in self-interference cancellation from antenna design to digital domain. Moreover, the reader will discover analytical and empirical models to deal with residual self-interference and to assess its effects in various scenarios and applications. Therefore, this is a highly informative and carefully presented book by the leading scientists in the area, providing a comprehensive overview of full-duplex technology from the perspective of various researchers, and research groups worldwide. This book is designed for researchers and professionals working in wireless communications and engineers willing to understand the challenges and solutions full-duplex communication so to implement a full-duplex system.

Adaptive Relay Techniques for OFDM-based Cooperative Communication Systems

Download Adaptive Relay Techniques for OFDM-based Cooperative Communication Systems PDF Online Free

Author :
Release : 2014
Genre :
Kind :
Book Rating : /5 ( reviews)

Adaptive Relay Techniques for OFDM-based Cooperative Communication Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Adaptive Relay Techniques for OFDM-based Cooperative Communication Systems write by Xin Gao. This book was released on 2014. Adaptive Relay Techniques for OFDM-based Cooperative Communication Systems available in PDF, EPUB and Kindle. Cooperative communication has recently been considered as a key technology for modern wireless standards and next generation wireless networks to improve the quality-of-service (QoS) and extend transmission coverage in a cost-e ective manner. In this thesis, we aim to address the challenges of wireless cooperative communications, and design the e cient OFDM-based relay systems. Starting with the channel accumulation problem in the amplify-and-forward (AF) relay system, we proposed two adaptive guard interval (GI) schemes for single/multiple-relay networks respectively to cover the accumulated delay spread and enhance the transmission e - ciency. Distinct from the traditional adaptive GI, the dynamical GI length can be detected by the destination individually. Numerical results show that the proposed scheme can further save the control signaling overhead without any symbol error rate (SER) performance loss. For multiple-relay systems, a novel relay selection criterion is proposed to achieve the trade-off between the transmission reliability and overhead by considering both the channel gain and the accumulated delay spread. From computer simulations, the proposed relay selection scheme significantly improves the e cient throughput over the multipath channel with variable channel length, Moreover, cooperative systems require an accuracy resource allocation to achieve the high capacity in the two-way decode-and-forward (DF) relay system with time-varying channels and the bidirectional asymmetric tra c. We propose two allocation algorithms, where the total capacity is maximized under a capacity ratio constraint which depends on the tra c-load di erence between the uplink and downlink. The balanced capacity performance shows that the proposed schemes can assure the fairs data rate of the two terminals and improve the overall QoS of the relay network. A low-complexity suboptimal allocation algorithm is proposed for the frequency-division model which separates subcarrier and time/power allocation. Verifying by simulations, the suboptimal scheme can achieve the similar performance with the optimal one with reduced complexity. In order to further enhance the transmission reliability and maintain low processing delay, we propose a novel equalize-and-forward (EF) relay scheme, which can equalizes the channel between source and relay and eliminate the channel accumulation e ect. The relay processing time is reduced by performing the channel estimation and equalization in parallel. In the EF relay, free-delay equalization is realized by presetting the equalizer with the current channel response that is predicted in parallel. Numerical results show that the EF relay can achieve comparable SER performance as the DF relay with much less latency and exhibit low outage probability at the same data rate as compared to traditional AF and DF schemes.

New Directions in Wireless Communications Research

Download New Directions in Wireless Communications Research PDF Online Free

Author :
Release : 2009-08-19
Genre : Technology & Engineering
Kind :
Book Rating : 738/5 ( reviews)

New Directions in Wireless Communications Research - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook New Directions in Wireless Communications Research write by Vahid Tarokh. This book was released on 2009-08-19. New Directions in Wireless Communications Research available in PDF, EPUB and Kindle. New Directions in Wireless Communications Research addresses critical issues in the design and performance analysis of current and future wireless system design. Intended for use by system designers and academic researchers, the contributions are by acknowledged international leaders in their field. Topics covered include: (1) Characterization of wireless channels; (2) The principles and challenges of OFDM; (3) Low-correlation sequences for communications; (4) Resource allocation in wireless systems; (5) Signal processing for wireless systems, including iterative systems collaborative beamforming and interference rejection and network coding; (6) Multi-user and multiple input-multiple output (MIMO) communications; (7) Cooperative wireless networks, cognitive radio systems and coded bidirectional relaying in wireless networks; (8) Fourth generation standards such as LTE and WiMax and standard proposals such as UMB. With chapters from some of the leading researchers in the field, this book is an invaluable reference for those studying and practicing in the field of wireless communications. The book provides the most recent information on topics of current interest to the research community including topics such as sensor networks, coding for networks, cognitive networks and many more.