Download or read book Performance Analysis of the Effect of Pulsed Noise Interference on WLAN Signals Transmitted Over a Nakagami Fading Channel written by Andreas Tsoumanis and published by . This book was released on 2004-03 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis examines the performance of wireless local area network (WLAN) signals, specifically, the signal of IEEE 802,1 la standard, The signal is subject to pulsed noise jamming, when either the desired signal alone or the desired signal and the jamming signal are subject to Nakagami fading, As expected, the implementation of forward error correction (FEC) coding with soft decision decoding (SDD) and maximum- likelihood detection improves performance as compared to uncoded signals, In addition, the combination of maximum- likelihood detection and error connection coding renders pulsed-noise jamming ineffective as compared to bandage noise jamming, When the jamming signal encounters fading as well, we assume that the average jamming power is much greater than the AWGN power, For uncoded signals, a jamming signal that experiences fading actually improves performance when the parameter of the information signal m(s) is less than or equal to one, Surprisingly, for larger values of m(s) a jamming signal that experiences fading works in favor of the information signal only for small signal-to- interference ratio (SIR), When SIR is large, performance when the jamming signal experiences fading is worse relative to performance when the jamming signal does not experience fading, For error correction coding with SDD, we investigate only continuous jamming since it is by far the worst-case, Moreover, while we consider a range of fading conditions for the jamming signal, we examine only Rayleigh fading of the information signal, The coded signal, when the jamming signal experiences severe fading, performs better relative to the case when the jamming signal does not experience fading,

Download or read book Performance Analysis of Wireless LAN Signals Transmitted Over a Ricean Fading Channel in a Pulsed Noise Interference Environment written by Evaggelos Spyrou and published by . This book was released on 2004-09 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis examines the performance of the waveforms specified by the IEEE 802.11a wireless local area network standard when the signal is transmitted over a Ricean fading channel with AWGN and pulsed noise interference. The pulsed interference is assumed to have constant average power and is either fading or nonfading. The probability of bit error is conditional on the received signal to noise power ratio, which is modeled as a random variable. The probability density function of this random variable is obtained either analytically or numerically for each modulation type, and the probability of bit error is evaluated as the expected value of the conditional probability. In one case, use is made of a new technique for the numerical inverse of the Laplace transform in order to evaluate numerically the signal to noise ratio probability density function. Due to the complexity of the analysis when both the signal and the interference are subject to Ricean fading, the analysis was simplified by assuming Ricean signal fading with Rayleigh interference fading and vice versa. The results of the analysis show that performance is affected by the degree of signal fading and also depends on the pulsed interference duty cycle. The signal to interference power ratio affects the way performance depends on these two factors.

Download or read book Performance Analysis of the IEEE 802 11G Waveform Transmitted Over a Fading Channel with Pulse noise Interference written by and published by . This book was released on 2006 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of the most promising wireless local area network (WLAN) standards today, IEEE 802.11g, which specifies orthogonal frequency-division multiplexing in order to avoid multi-path effects and at the same time achieve high data rates, was examined in this thesis. We investigated four different receivers and analyzed their performance with Viterbi soft decision decoding when the signal was transmitted over a slow, flat fading Nakagami channel for AWGN only, as well as for AWGN plus pulse-noise interference. The implementation of forward error correction coding with soft decision decoding improves the performance compared to uncoded signal if pulse-noise interference is not present. The scenarios when no side information is available (linear-combining receiver), when perfect side information is available (noise-normalizing receiver), and two alternatives to the noise-normalized receiver with much coarser side information (modified noise-normalized receiver and noise-normalized receiver with normalization error) are examined. All the scenarios are examined for various fading and interference conditions. The performance of the noise-normalized receiver is, as expected, much improved compared to the linear-combining receiver when PNI is present. Finally, the noise-normalized receiver with normalization error achieves the same or better performance than the noise-normalized receiver without the exact interference noise power.

Download or read book Proceedings written by and published by . This book was released on 2004 with total page 582 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis of IEEE 802 11g Receivers With Erasure Decoding to Mitigate the Effects of Pulse Noise Interference written by Georgios Zouros and published by . This book was released on 2006 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: The performance of IEEE 802.11g wireless local area network (WLAN) standard receivers when the signal is transmitted over a frequency-selective, slowly fading Nakagami channel in a pulse-noise interference environment when errors-and-erasures Viterbi decoding is used is examined. The different combinations of modulation (both binary and non-binary) and convolutional code rate specified by the WLAN standard are examined. The performance obtained with errors-and-erasures decoding (EED) is compared with the performance obtained with errors-only hard decision Viterbi decoding (HDD) as well as that obtained with soft decision Viterbi decoding (SDD) for binary modulation, while for non-binary modulation, EED performance is compared with HDD performance. It was found that EED can significantly improve performance under some conditions when pulse-noise interference is present.

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 2304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Embracing Interference in Wireless Systems written by Shyamnath Gollakota and published by Morgan & Claypool. This book was released on 2014-06-01 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: The wireless medium is a shared resource. If nearby devices transmit at the same time, their signals interfere, resulting in a collision. In traditional networks, collisions cause the loss of the transmitted information. For this reason, wireless networks have been designed with the assumption that interference is intrinsically harmful and must be avoided. This book, a revised version of the author's award-winning Ph.D. dissertation, takes an alternate approach: Instead of viewing interference as an inherently counterproductive phenomenon that should to be avoided, we design practical systems that transform interference into a harmless, and even a beneficial phenomenon. To achieve this goal, we consider how wireless signals interact when they interfere, and use this understanding in our system designs. Specifically, when interference occurs, the signals get mixed on the wireless medium. By understanding the parameters of this mixing, we can invert the mixing and decode the interfered packets; thus, making interference harmless. Furthermore, we can control this mixing process to create strategic interference that allow decodability at a particular receiver of interest, but prevent decodability at unintended receivers and adversaries. Hence, we can transform interference into a beneficial phenomenon that provides security. Building on this approach, we make four main contributions: We present the first WiFi receiver that can successfully reconstruct the transmitted information in the presence of packet collisions. Next, we introduce a WiFi receiver design that can decode in the presence of high-power cross-technology interference from devices like baby monitors, cordless phones, microwave ovens, or even unknown technologies. We then show how we can harness interference to improve security. In particular, we develop the first system that secures an insecure medical implant without any modification to the implant itself. Finally, we present a solution that establishes secure connections between any two WiFi devices, without having users enter passwords or use pre-shared secret keys.

Download or read book Performance of Wireless Communication Systems in Ultra wideband Interference and Non Gaussian Noise written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The growing demand for high speed wireless applications and the scarcity of the spectral resources has necessitated the development of new concepts that enable more efficient utilization of the frequency spectrum. Ultra-wideband (UWB) is an emerging technology that is capable of utilizing the spectral resources more effectively by sharing the spectrum with other applications. This spectrum sharing however can potentially result in harmful interference from UWB systems to devices co-existing in the same frequency band. Therefore, in order to guarantee peaceful co-existence, the effects of UWB interference on co-existing systems have to be carefully analyzed. Towards this goal, in this thesis, we first study the effects of multi-band (MB) orthogonal frequency-division multiplexing (OFDM) UWB interference on a generic uncoded narrowband (NB) system. For this purpose, we develop analytical expressions for the amplitude probability distribution (APD) and the bit error rate (BER) performance of the NB system in the presence of MB-OFDM interference. We use the obtained results to assess the accuracy of the Gaussian approximation (GA) for MB-OFDM UWB interference. We show that for most channel models and signal bandwidths the GA is unable to accurately predict the NB system performance and the exact BER analysis has to be used to obtain meaningful results. We also analyze the effects of UWB interference in a more general framework that allows us to study the impact of general types of non-Gaussian noise and interference on generic uncoded victim systems. Specifically, we present a unified asymptotic symbol error rate (SER) analysis of linearly modulated systems impaired by fading and generic non- Gaussian noise and interference. Our analysis also encompasses diversity reception with equal gain and selection combining and is extended to binary orthogonal modulation. The obtained asymptotic results show that for high signal-to-noise ratios (SNRs) the SER of the victim system.

Download or read book Science and Technology Assistant Ed K R Rider F R Taylor written by and published by . This book was released on 1966 with total page 483 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis of the OFDM Based WLAN System Over Fading Channel with Non Ideal Effects written by 李冠佑 and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Analysis of Wireless Fading Channels written by Omar Ahmad Alhussein and published by . This book was released on 2015 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents two major contributions. First, we consider a unified approach to model and simplify wireless fading channels or potentially fading scenarios by mixture distributions, namely using the mixture of Gaussian (MoG) and the mixture Gamma (MG) distributions. The approximation methodologies rely on maximum a posteriori and likelihood estimation techniques, such as the expectation-maximization and variational Bayes. Through the use of the mean-square error and the Kullback-Leibler divergence measures, we show that our models provide similar accuracy yet simpler representation than other existing models. In addition, we provide closed-form expressions or approximations for several performance metrics used in wireless communication systems, including the moment generating function, the raw moments, the amount of fading, the outage probability, and the average channel capacity. Second, through the use of the MoG and MG distributions, we provide a unifying and verstaile performance analysis over intricate generalized and composite fading channels in several contemporary wireless research topics, such as cognitive radio networks, cooperative- and diversity-based communications, and impulsive noise environments. The new approach and proposed distributions resolves intractable problems in many other fields, such as cognitive radio networks, cooperative networks, cascaded wireless applications and others.

Download or read book WLAN CSMA CA Performance in a Bluetooth Interference Environment written by Randall B. Noel and published by . This book was released on 2003-03-01 with total page 90 pages. Available in PDF, EPUB and Kindle. Book excerpt: IEEE 802.11 WLANs and Bluetooth piconets both operate in the 2.4 GHz Industrial Scientific and Medical (ISM) radio band. When operating in close proximity, these two technologies interfere with each other. Current literature suggests that IEEE 802.11 (employing direct sequence spread spectrum technology) is more susceptible to this interference than Bluetooth, which uses frequency hopping spread spectrum technology, resulting in reduced throughput. Current research tends to focus on the issue of packet collisions, and not the fact that IEEE 802.11 may also delay its transmissions while the radio channel is occupied by a Bluetooth signal. This research characterizes previously neglected transmission delay effects. Through analytic modeling and simulation, the impact of this interference is determined to identify all facets of the interference issues. Results show that Bluetooth-induced transmission delays improve network performance in many scenarios. When isolating delay effects, the likelihood that WLAN STA signals collide with each other decreases, causing an overall increase in normalized throughput and decrease in expected delay for many network configurations, As wireless communication technologies become an integral part of national defense, it is imperative to understand every performance characteristic. For instance, if the Air Force uses IEEE 802.11 and wants to incorporate a Bluetooth piconet as well, the impact of concurrent operation should be known beforehand. Since IEEE 802,11 and Bluetooth technologies could become vital for the Air Force to maintain its position of air superiority, all the strengths, weaknesses, and limitations of these systems should be understood.

Download or read book Space Modulation Techniques written by Raed Mesleh and published by John Wiley & Sons. This book was released on 2018-06-19 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explores the fundamentals required to understand, analyze, and implement space modulation techniques (SMTs) in coherent and non-coherent radio frequency environments This book focuses on the concept of space modulation techniques (SMTs), and covers those emerging high data rate wireless communication techniques. The book discusses the advantages and disadvantages of SMTs along with their performance. A general framework for analyzing the performance of SMTs is provided and used to detail their performance over several generalized fading channels. The book also addresses the transmitter design of these techniques with the optimum number of hardware components and the use of these techniques in cooperative and mm-Wave communications. Beginning with an introduction to the subject and a brief history, Space Modulation Techniques goes on to offer chapters covering MIMO systems like spatial multiplexing and space-time coding. It then looks at channel models, such as Rayleigh, Rician, Nakagami-m, and other generalized distributions. A discussion of SMTs includes techniques like space shift keying (SSK), space-time shift keying (STSK), trellis coded spatial modulation (TCSM), spatial modulation (SM), generalized spatial modulation (GSM), quadrature spatial modulation (QSM), and more. The book also presents a non-coherent design for different SMTs, and a framework for SMTs’ performance analysis in different channel conditions and in the presence of channel imperfections, all that along with an information theoretic treatment of SMTs. Lastly, it provides performance comparisons, results, and MATLAB codes and offers readers practical implementation designs for SMTs. The book also: Provides readers with the expertise of the inventors of space modulation techniques (SMTs) Analyzes error performance, capacity performance, and system complexity. Discusses practical implementation of SMTs and studies SMTs with cooperative and mm-Wave communications Explores and compares MIMO schemes Space Modulation Techniques is an ideal book for professional and academic readers that are active in the field of SMT MIMO systems.

Download or read book Performance Analysis of Generalized Selection Combining in Arbitrarily Correlated Nakagami Fading Channels written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Mobile communication technologies have grown significantly in recent years. In order to satisfy the increasing number of users and their ever increasing requirements, there have been continuous enhancements in present-day wireless standards. With the proliferation of these standards, use of conventional techniques for improving receiver performance becomes very complex. Hence, the design and analysis of low complexity suboptimal techniques, which are comparable to optimal techniques on performance basis and consume less power, has received tremendous interest in a research community. Along these lines this thesis analyzes a suboptimal diversity combining system called generalized selection combining (GSC). In this thesis, we develop an analytical framework for error rate analysis of the GSC technique in a correlated Nakagami fading environment. We derive the moment generating function of the output SNR of a GSC system and, using the moment generating function, the bit error rate of the system is derived. We show that our developed analytical expressions converge to the results presented in literature for the special cases of independent identically distributed GSC with Rayleigh and Nakagami fading, and maximal ratio combining with IID Nakagami fading. Finally, the analytical equations are plotted, verified and compared with the results from system simulations.

Download or read book Modelling the Wireless Propagation Channel written by Fernando P¿rez Font¿n and published by John Wiley & Sons. This book was released on 2008-09-15 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: A practical tool for propagation channel modeling with MATLAB® simulations. Many books on wireless propagation channel provide a highly theoretical coverage, which for some interested readers, may be difficult to follow. This book takes a very practical approach by introducing the theory in each chapter first, and then carrying out simulations showing how exactly put the theory into practice. The resulting plots are analyzed and commented for clarity, and conclusions are drawn and explained from the obtained results. Key features include: A unique approach to propagation channel modeling with accompanying MATLAB® simulations to demonstrate the theory in practice Contains step by step commentary and analysis of the obtained simulation results in order to provide a comprehensive and structured learning tool Covers a wide range of topics including shadowing effects, coverage and interference, Multipath Narrowband channel, Multipath Wideband channel, propagation in micro and pico-cells, the land mobile satellite (LMS) channel, the directional Multipath channel and MIMO and propagation effects in fixed radio links (terrestrial and satellite) The book comes with an accompanying website that contains the MATLAB® simulations and allows readers to try them out themselves Well suited for lab-use, as reference and as a self-learning tool both for advanced students and professionals Modeling the Wireless Propagation Channel: A simulation approach with MATLAB® will be best suited for postgraduate (Masters and PhD) students and practicing engineers in telecommunications and electrical engineering fields, who are seeking to familiarise themselves with the topic without too many formulas. The book will also be of interest to network engineers, system engineers and researchers

Download or read book Principles of Mobile Communication written by Gordon L. Stüber and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 670 pages. Available in PDF, EPUB and Kindle. Book excerpt: Principles of Mobile Communication provides an authoritative treatment of the fundamentals of mobile communications, one of the fastest growing areas of the modern telecommunications industry. The book stresses the fundamentals of mobile communications engineering that are important for the design of any mobile system. Less emphasis is placed on the description of existing and proposed wireless standards. This focus on fundamental issues should be of benefit not only to students taking formal instruction but also to practising engineers who are likely to already have a detailed familiarity with the standards and are seeking to deepen their knowledge of this important field. The book stresses mathematical modeling and analysis, rather than providing a qualitative overview. It has been specifically developed as a textbook for graduate level instruction and a reference book for practising engineers and those seeking to pursue research in the area. The book contains sufficient background material for the novice, yet enough advanced material for a sequence of graduate level courses. Principles of Mobile Communication treats a variety of contemporary issues, many of which have been treated before only in the journals. Some material in the book has never appeared before in the literature. The book provides an up-to-date treatment of the subject area at a level of detail that is not available in other books. Also, the book is unique in that the whole range of topics covered is not presently available in any other book. Throughout the book, detailed derivations are provided and extensive references to the literature are made. This is of value to the reader wishing to gain detailed knowledge of a particular topic.

Download or read book MIMO OFDM Wireless Communications with MATLAB written by Yong Soo Cho and published by John Wiley & Sons. This book was released on 2010-08-20 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: MIMO-OFDM is a key technology for next-generation cellular communications (3GPP-LTE, Mobile WiMAX, IMT-Advanced) as well as wireless LAN (IEEE 802.11a, IEEE 802.11n), wireless PAN (MB-OFDM), and broadcasting (DAB, DVB, DMB). In MIMO-OFDM Wireless Communications with MATLAB®, the authors provide a comprehensive introduction to the theory and practice of wireless channel modeling, OFDM, and MIMO, using MATLAB® programs to simulate the various techniques on MIMO-OFDM systems. One of the only books in the area dedicated to explaining simulation aspects Covers implementation to help cement the key concepts Uses materials that have been classroom-tested in numerous universities Provides the analytic solutions and practical examples with downloadable MATLAB® codes Simulation examples based on actual industry and research projects Presentation slides with key equations and figures for instructor use MIMO-OFDM Wireless Communications with MATLAB® is a key text for graduate students in wireless communications. Professionals and technicians in wireless communication fields, graduate students in signal processing, as well as senior undergraduates majoring in wireless communications will find this book a practical introduction to the MIMO-OFDM techniques. Instructor materials and MATLAB® code examples available for download at www.wiley.com/go/chomimo