Doctoral Thesis / Dissertation from the year 2011 in the subject Computer Science - Internet, New Technologies, grade: 10.00, , course: Ph.D., language: English, abstract: As per recommendations of International Mobile Telecommunications-2000 (IMT-2000), the future wireless communication is bound to occupy the features including high-speed data and broadband transmission, high capacity to support a huge number of simultaneous users, global mobility, high security, and scalable quality of service (QoS) along with low cost for both operators and subscribers. The above features are imposing technical challenges on system design and stimulating various research topics on capacity, complexity and performance. In order to increase the capacity of wireless networks, various multiple access schemes have been reported in the literature. The credit of most competent multiple access scheme in 2G systems goes to CDMA scheme which offers an even better bandwidth-efficiency than TDMA and FDMA schemes, however, its implementation is quite difficult due to involvement of rather complex technologies including complex power-control, and multiuser detection techniques etc. The requirement of alternate mechanism for user separation has been solved by Interleave-Division Multiple-Access (IDMA) scheme, in which, most of above stated problems do not exist due to application of user-specific interleavers having low cross-correlation amongst them. The interleaved data resulted from user-specific interleavers, demonstrates better orthogonality amongst each other in the channel. The condition of orthogonality is maintained for reducing the risk of collision amongst the interleavers during communication process. In IDMA scheme, orthogonal interleavers are employed as the only means for user separation and, hence, are referred as the heart of the scheme. The selection of interleaver along with optimum design methodology for proposed tree based interleaving (TBI) mechanism for IDMA scheme fulfilling the requirement of orthogonality and easy implementation. In the beginning of work, the mechanism of interleaving with necessary conditions is presented. Later, the performance and analysis of proposed TBI mechanism with IDMA scheme has been presented. Apart from the bit error rate (BER) performance analysis, the interleavers have also been analyzed on the basis of memory requirement and computational complexity at transmitter and receiver ends. Here, The performance evaluation of IDMA scheme with proposed tree based interleaving (TBI) mechanism, in uncoded and coded environments, has been duly investigated along with its implementation.

In this paper, we have evaluated Bit Error Rate (BER) performance of interleave-division multiple-access (IDMA) systems with BPSK & QPSK modulation techniques when the system is subjected to Additive White Gaussian Noise (AWGN) in the channel. The BPSK and QPSK modulation techniques are already well trusted techniques with code division multiple-access (CDMA) systems however, IDMA scheme is referred as the extension of CDMA scheme. The simulation results demonstrate the superior performance of QPSK modulation in comparison to that of BPSK modulation method apart from the inherited advantage of better spectrum utilization. Thus, with the QPSK modulation exposes optimum and efficient data rate to mobile terminal for IDMA schemes.

The Code-Division Multiple-Access (CDMA) scheme is well established mechanism for sharing of bandwidth however its performance is mainly limited by multiple access interference (MAI) and inter-symbol interference (ISI). Newly proposed Interleave division multiple access (IDMA) scheme has established its position for a potential candidate for 4th generation wireless communication systems. It combines the advantage of chip level user-specific interleavers with iterative chip-by-chip (CBC) multiuser detection (MUD) for spread spectrum communication. IDMA not only inherits all the advantages of CDMA but also has the capability to overcome its deficiencies. The number of various interleavers has been proposed by researchers to meet the future requirements in IDMA communication system. All the proposed interleavers shares certain merits and demerits over one another and still the scope for proposal of most optimum interleaver for IDMA systems is open for researchers. In this paper, various interleavers have been reviewed for this advanced multiple access scheme.

This book constitutes the refereed proceedings of the International Conference on Advances in Computing Communications and Control, ICAC3 2011, held in Mumbai, India, in January 2011. The 84 revised full papers presented were carefully reviewed and selected from 309 submissions. The papers address issues such as AI, artificial neural networks, computer graphics, data warehousing and mining, distributed computing, geo information and statistical computing, learning algorithms, system security, virtual reality, cloud computing, service oriented architecture, semantic web, coding techniques, modeling and simulation of communication systems, network architecture, network protocols, optical fiber/microwave communication, satellite communication, speech/image processing, wired and wireless communication, cooperative control, and nonlinear control, process control and instrumentation, industrial automation, controls in aerospace, robotics, and power systems.

This thesis discusses a new multiuser detection technique for cellular wireless communications. Multiuser communications is critical in cellular systems as multiple terminals (users) transmit to base stations (or wireless infrastructure). Efficient receiver methods are needed to maximise the performance of these links and maximise overall throughput and coverage while minimising inter-cell interference. Recently a new technique, Interleave-Division Multiple Access (IDMA), was developed as a variant of direct-sequence code division multiple access (DS-CDMA). In this new scheme users are separated by user specific interleavers, and each user is allocated a low rate code. As a result, the bandwidth expansion is devoted to the low rate code and not weaker spreading codes. IDMA has shown to have significant performance gains over traditional DS-CDMA with a modest increase in complexity. The literature on IDMA primarily focuses on the design of low rate forward error correcting (FEC) codes, as well as channel estimation. However, the practical aspects of an IDMA receiver such as timing acquisition, tracking, block asynchronous detection, and cellular analysis are rarely studied. The objective of this thesis is to design and analyse practical synchronisation, detection and power optimisation techniques for IDMA systems. It also, for the first time, provides a novel analysis and design of a multi-cell system employing a general multiuser receiver. These tools can be used to optimise and evaluate the performance of an IDMA communication system. The techniques presented in this work can be easily employed for DS-CDMA or other multiuser receiver designs with slight modification. Acquisition and synchronisation are essential processes that a base-station is required to perform before user's data can be detected and decoded. For high capacity IDMA systems, which can be heavily loaded and operate close to the channel capacity, the performance of acquisition and tracking can be severely affected by multiple access interference as well as severe drift. This thesis develops acquisition and synchronisation algorithms which can cope with heavy multiple access interference as well as high levels of drift. Once the timing points have been estimated for an IDMA receiver the detection and decoding process can proceed. An important issue with uplink systems is the alignment of frame boundaries for efficient detection. This thesis demonstrates how a fully asynchronous system can be modelled for detection. This thesis presents a model for the frame asynchronous IDMA system, and then develops a maximum likelihood receiver for the proposed system. This thesis develops tools to analyse and optimise IDMA receivers. The tools developed are general enough to be applied to other multiuser receiver techniques. The conventional EXIT chart analysis of unequal power allocated multiuser systems use an averaged EXIT chart analysis for all users to reduce the complexity of the task. This thesis presents a multidimensional analysis for power allocated IDMA, and shows how it can be utilised in power optimisation. Finally, this work develops a novel power zoning technique for multicell multiuser receivers using the optimised power levels, and illustrates a particular example where there is a 50% capacity improvement using the proposed scheme. -- provided by Candidate.

These proceedings focus on various aspects of computer science and its applications, thus providing an opportunity for academic and industry professionals to discuss the latest issues and progress in this and related areas. The book includes theory and applications alike.

Recent developments in parallel computing for various fields of application are providing improved solutions for handling data. These newer, innovative ideas offer the technical support necessary to enhance intellectual decisions, while also dealing more efficiently with the huge volumes of data currently involved. This book presents the proceedings of ICAPTA 2022, the International Conference on Advances in Parallel Computing Technologies and Applications, hosted as a virtual conference from Bangalore, India, on 27 and 28 January 2022. The aim of the conference was to provide a forum for the sharing of knowledge about various aspects of parallel computing in communications systems and networking, including cloud and virtualization solutions, management technologies and vertical application areas. The conference also provided a premier platform for scientists, researchers, practitioners and academicians to present and discuss their most recent innovations, trends and concerns, as well as the practical challenges encountered in this field. More than 300 submissions were received for the conference, from which the 91 full-length papers presented here were accepted after review by a panel of subject experts. Topics covered include parallel computing in communication, machine learning intelligence for parallel computing and parallel computing for software services in theoretical and practical aspects. Providing an overview of recent developments in the field, the book will be of interest to all those whose work involves the use of parallel computing technologies.

WIRELESS COMMUNICATION SIGNALS A practical guide to wireless communication systems and concepts Wireless technologies and services have evolved significantly over the last couple of decades, and Wireless Communication Signals offers an important guide to the most recent advances in wireless communication systems and concepts grounded in a practical and laboratory perspective. Written by a noted expert on the topic, the book provides the information needed to model, simulate, test, and analyze wireless system and wireless circuits using modern instrumentation and computer aided design software. Designed as a practical resource, the book provides a clear understanding of the basic theory, software simulation, hardware test, and modeling, system component testing, software and hardware interactions and co-simulations. This important book: Provides organic and harmonized coverage of wireless communication systems Covers a range of systems from radio hardware to digital baseband signal processing Presents information on testing and measurement of wireless communication systems and subsystems Includes MATLAB file codes Written for professionals in the communications industry, technical managers, and researchers in both academia and industry. Wireless Communication Signals introduces wireless communication systems and concepts from both a practical and laboratory perspective.

This book gathers papers addressing state-of-the-art research in all areas of information and communication technologies and their applications in intelligent computing, cloud storage, data mining and software analysis. It presents the outcomes of the Fourth International Conference on Information and Communication Technology for Intelligent Systems, which was held in Ahmedabad, India. Divided into two volumes, the book discusses the fundamentals of various data analysis techniques and algorithms, making it a valuable resource for researchers and practitioners alike.

This book is composed of the Proceedings of the International Conference on Advanced Computing, Networking, and Informatics (ICACNI 2013), held at Central Institute of Technology, Raipur, Chhattisgarh, India during June 14–16, 2013. The book records current research articles in the domain of computing, networking, and informatics. The book presents original research articles, case-studies, as well as review articles in the said field of study with emphasis on their implementation and practical application. Researchers, academicians, practitioners, and industry policy makers around the globe have contributed towards formation of this book with their valuable research submissions.