It is shown that, particularly for terrestrial cellular telephony, the interference-suppression feature of CDMA (code division multiple access) can result in a many-fold increase in capacity over analog and even over competing digital techniques. A single-cell system, such as a hubbed satellite network, is addressed, and the basic expression for capacity is developed. The corresponding expressions for a multiple-cell system are derived. and the distribution on the number of users supportable per cell is determined. It is concluded that properly augmented and power-controlled multiple-cell CDMA promises a quantum increase in current cellular capacity. >

On the capacity of a cellular CDMA system

Praise for the Third Edition: "This is one of the best books available. Its excellent organizational structure allows quick reference to specific models and its clear presentation . . . solidifies the understanding of the concepts being presented."IIE Transactions on Operations EngineeringThoroughly revised and expanded to reflect the latest developments in the field, Fundamentals of Queueing Theory, Fourth Edition continues to present the basic statistical principles that are necessary to analyze the probabilistic nature of queues. Rather than presenting a narrow focus on the subject, this update illustrates the wide-reaching, fundamental concepts in queueing theory and its applications to diverse areas such as computer science, engineering, business, and operations research.This update takes a numerical approach to understanding and making probable estimations relating to queues, with a comprehensive outline of simple and more advanced queueing models. Newly featured topics of the Fourth Edition include:Retrial queuesApproximations for queueing networksNumerical inversion of transformsDetermining the appropriate number of servers to balance quality and cost of serviceEach chapter provides a self-contained presentation of key concepts and formulae, allowing readers to work with each section independently, while a summary table at the end of the book outlines the types of queues that have been discussed and their results. In addition, two new appendices have been added, discussing transforms and generating functions as well as the fundamentals of differential and difference equations. New examples are now included along with problems that incorporate QtsPlus software, which is freely available via the book's related Web site.With its accessible style and wealth of real-world examples, Fundamentals of Queueing Theory, Fourth Edition is an ideal book for courses on queueing theory at the upper-undergraduate and graduate levels. It is also a valuable resource for researchers and practitioners who analyze congestion in the fields of telecommunications, transportation, aviation, and management science.

Fundamentals of Queueing Theory

Information Theory and Reliable Communication

This document provides updates to IEEE Std 802.16's MIB for the MAC, PHY and asso- ciated management procedures in order to accommodate recent extensions to the standard.

IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed Broadband Wireless Access Systems Draft Amendment: Management Information Base Extensions

Ultra Wideband Signals and Systems in Communication Engineering

This paper presents the data distribution called smart remotely access distributed system (SRA-DS) One of the stated purposes of the SRA-DS is to provide a standard to users in order to provide constantly available system that satisfy trust requirement for network applications The trend in today's technology is no longer used in stand-alone units One of the major criticisms of this feature is not constant availability The purpose of this paper is to discuss the various aspects of monitoring and fault tolerant required for distributed system, and to describe the requirements needed in criteria from which can provide a low cost Web applications with distributed system

/pdf/smart-remotely-access-distributed-system-1qshwmg8y7.pdf

Smart remotely access distributed system

Hybrid Low Cost Flooding Scheme for On-demand Routing Protocols in Manets

In this paper we investigate 2 transmit and 1 receive (2Tx:1Rx) space-frequency orthogonal frequency division multiplexing (SF-OFDM) and space-time OFDM (ST-OFDM) concatenated with convolutional channel coding as a redundancy method to combat channel impairments. We built our SF and ST-OFDM on top of our coded OFDM (COFDM) with coding rate of 1/4 and constraint length of 10. We simulate our concatenated SF-OFDM and ST-OFDM over a multipath fading channel using Naftali 802.11 channel model under different delay spreads in relation to outdoor environment. Concatenated SF- OFDM performs slightly better than ST-OFDM at delay spread of 2.0 microseconds, but both are almost comparable at all other delay spreads. These two schemes outperforms other schemes such as single antenna coded OFDM and Alamouti's Space-Time Block Code (STBC) under these conditions by as much as 10 dB at BER of 104.

/pdf/a-full-rate-concatenated-space-frequency-and-space-time-ofdm-16k8j7btom.pdf

A Full Rate Concatenated Space-Frequency and Space-Time OFDM over Naftali Fading Channels

In this paper, an efficient superposition coding with adaptive modulation and coding (SP-AMC) system, for the optimal system performance, is proposed. The proposed SP-AMC system switches its modulation and coding scheme (MCS) adaptively in order to select the suitable modulation order and coding rate that are best match with the instantaneous channel condition. Hence, better performances in both data rate and error probability can be attained. Moreover, the source data is divided into a number of different priority layers with different importance. The bit streams of these layers are then encoded and modulated individually with different unequal error protection (UEP) levels against channel corruption. The highest UEP level is assigned to the highest priority layer which has the highest effect on the reception quality, and vice versa. The modulated bit streams of all layers are then superimposed together and transmitted over Rayleigh fading channel. At the receiver side, a multi-stage decoding (MSD) receiver is used to reconstruct the source data by applying the ordered successive interference cancellation (O-SIC) technique, which demodulates the layers according to the order of their priorities.

/pdf/sp-amc-scheme-for-visual-data-transmisson-over-wireless-3x9qtcdm3u.pdf

Borhanuddin Mohd Ali

Papers

Smart remotely access distributed system

Hybrid Low Cost Flooding Scheme for On-demand Routing Protocols in Manets

A Full Rate Concatenated Space-Frequency and Space-Time OFDM over Naftali Fading Channels

SP-AMC scheme for visual data transmisson over wireless fading channel

Evolution of Multiplexing Techniques in Wireless Communications Systems