Author: Mo ZhuPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Low Complexity Channel Estimation for OFDM Based Satellite Systems
Author: Mo ZhuLow-complexity Iterative Channel Estimation and Detection Techniques for OFDM Systems
Author: 耿念Publisher:
ISBN:
Category : Orthogonal frequency division multiplexing
Languages : en
Pages : 236
Book Description
Low-complexity Algorithms for Channel Estimation in Optimised Pilot-assisted Wireless OFDM Systems
Author: Eugene GolovinsAn EM-based Channel Estimation Algorithm for Space Time Block Coded MIMO OFDM Systems
Author: Haideh M. KarkhanechiPublisher:
ISBN:
Category :
Languages : en
Pages : 290
Book Description
Performance Analysis of DFT Based Channel Estimation in OFDM System
Author: Md. Muktar HossainPublisher: LAP Lambert Academic Publishing
ISBN: 9783659540608
Category :
Languages : en
Pages : 60
Book Description
In this book the channel estimation techniques for OFDM systems based on Block Type Pilot arrangement are investigated. Finally, the DFT based channel estimation technique is performed which gives better performance over LS and MMSE based channel estimation.With same SNR, the BER of DFT based channel estimation is less than the BER of LS and MMSE based channel estimation. The MMSE estimator has good performance but high complexity. The LS estimator has low complexity, but its performance is not as good as that MMSE estimator basically at low SNR. Block Type Pilot arrangement is suitable for frequency-selective channels. For the fast-fading channels, however, it might incur too much overhead to track the channel variation by reducing the pilot symbol period.As the use of pilot symbols for channel estimation decrease the spectrum efficiency of the wireless communication systems, it will be beneficial if we can adaptively change the number of pilot tones depending on the channel condition through some feedback information.
Wireless Communications
Author: Giorgio A. VitettaPublisher: John Wiley & Sons
ISBN: 1118576608
Category : Technology & Engineering
Languages : en
Pages : 849
Book Description
This book introduces the theoretical elements at the basis of various classes of algorithms commonly employed in the physical layer (and, in part, in MAC layer) of wireless communications systems. It focuses on single user systems, so ignoring multiple access techniques. Moreover, emphasis is put on single-input single-output (SISO) systems, although some relevant topics about multiple-input multiple-output (MIMO) systems are also illustrated. Comprehensive wireless specific guide to algorithmic techniques Provides a detailed analysis of channel equalization and channel coding for wireless applications Unique conceptual approach focusing in single user systems Covers algebraic decoding, modulation techniques, channel coding and channel equalisation
Iterative Channel Estimation for Wireless Communications
Author: JoonBeom KimPublisher:
ISBN: 9781109870985
Category :
Languages : en
Pages : 129
Book Description
Finally, for vertical Bell Laboratories layered space-time OFDM systems, we propose an iterative channel estimator based on a PSAM structure for time-varying multipath fading channels. By exploiting the statistical properties of a wireless channel, we also develop a method to suppress intercarrier interference due to the channel time selectivity, and propose a low-complexity iterative channel estimator that exploits a priori information in an efficient manner.
Cooperative Communications
Author: Mischa DohlerPublisher: John Wiley & Sons
ISBN: 9780470740064
Category : Technology & Engineering
Languages : en
Pages : 464
Book Description
Facilitating Cooperation for Wireless Systems Cooperative Communications: Hardware, Channel & PHY focuses on issues pertaining to the PHY layer of wireless communication networks, offering a rigorous taxonomy of this dispersed field, along with a range of application scenarios for cooperative and distributed schemes, demonstrating how these techniques can be employed. The authors discuss hardware, complexity and power consumption issues, which are vital for understanding what can be realized at the PHY layer, showing how wireless channel models differ from more traditional models, and highlighting the reliance of PHY algorithm performance on the underlying channel models. Numerous transparent and regenerative relaying protocols are described in detail for a variety of transparent and regenerative cooperative schemes. Key Features: Introduces background, concepts, applications, milestones and thorough taxonomy Identifies the potential in this emerging technology applied to e.g. LTE/WiMAX, WSN Discusses latest wireless channel models for transparent and regenerative protocols Addresses the fundamentals as well as latest emerging PHY protocols Introduces transparent distributed STBC, STTC, multiplexing and beamforming protocols Quantifies regenerative distributed space-time, channel and network coding protocols Explores system optimization, such as distributed power allocation and relay selection Introduces and compares analog and digital hardware architectures Quantifies complexity, memory and power consumption of 3G UMTS & 4G LTE/WiMAX relay Highlights future research challenges within the cooperative communications field This book is an invaluable guide for professionals and researchers in communications fields. It will also be of interest to graduates of communications and electronic engineering courses. It forms part of an entire series dedicated to cooperative wireless systems.
Receiver Designs for Ofdm Systems with Space-Frequency Diversity
Author: Siva MuruganathanPublisher: LAP Lambert Academic Publishing
ISBN: 9783838339092
Category :
Languages : en
Pages : 184
Book Description
This monograph focuses on the design of low complexity interference cancellation and channel estimation algorithms for two different space-frequency coded OFDM system configurations. The first of these configurations is space-frequency block coded OFDM (SFBC-OFDM) which yields performance improvement mainly by exploiting spatial diversity. To attain further performance improvement, a concatenated SFBC-OFDM system configuration, which exploits both spatial and frequency diversities inherent in multiple-input multiple-output multi-path channels, is considered next. In addition to presenting computationally efficient receiver designs for the two above-mentioned system configurations, the monograph also investigates the performance of the proposed receivers via accurate analytical and simulation methods under various channel conditions. Furthermore, the performances and complexities associated with the designed receiver structures are quantified and compared with those corresponding to the receivers that already exist in the literature.
Channel Estimation Algorithms for OFDM in Interference Scenarios
Author: Farah ZaarourPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
The scarcity of the radio spectrum and the increasing demand on bandwidth makes it vital to optimize the spectrum use. While a maximum efficiency should be attained, a minimal interference level should be maintained. OFDM has been selected as the modulation scheme in several wireless standards. Channel estimation is a fundamental task in OFDM and it becomes even more challenging in the presence of interference. In this thesis, our aim is to propose channel estimation algorithms for OFDM systems in the presence of interference, where conventional channel estimators designed for OFDM fail. First, we consider the cognitive radio environment and propose a novel channel estimation framework for fast time-varying channels in OFDM with NBI. This is accomplished through an expectation maximization (EM) based algorithm. This formulation allows us to obtain a closed-form expression for the estimation of the noise power. In this thesis, we are particularly interested in a very recent scheme of superimposed pilots for OFDM (DNSP). DNSP assures interference-free pilots at the expense of data interference. Seen the modernity of DNSP, a suitable receiver has to be designed to cope with its design. We first propose a low-complexity interference canceler (IC) for slow time-varying channels with DNSP. The performance of the proposed IC is guaranteed when the channel estimation error is small. As another contribution, we extend the design of the approximated IC for DNSP so as to take the channel estimation errors into account. Finally, we consider robust channel estimation which can be viewed as one of the perspectives of this thesis.