Rias Muhamed

Bio: Rias Muhamed is an academic researcher from AT&T. The author has contributed to research in topics: WiMAX & Network Access Device. The author has an hindex of 16, co-authored 18 publications receiving 3231 citations.

Fundamentals of WiMAX: Understanding Broadband Wireless Networking

Abstract: This is the eBook version of the printed book. Praise for Fundamentals of WiMAX "This book is one of the most comprehensive books I have reviewed ... it is a must-read for engineers and students planning to remain current or who plan to pursue a career in telecommunications. I have reviewed other publications on WiMAX and have been disappointed. This book is refreshing in that it is clear that the authors have the in-depth technical knowledge and communications skills to deliver a logically laid out publication that has substance to it." Ron Resnick, President, WiMAX Forum "This is the first book with a great introductory treatment of WiMAX technology. It should be essential reading for all engineers involved in WiMAX. The high-level overview is very useful for those with non-technical background. The introductory sections for OFDM and MIMO technologies are very useful for those with implementation background and some knowledge of communication theory. The chapters covering physical and MAC layers are at the appropriate level of detail. In short, I recommend this book to systems engineers and designers at different layers of the protocol, deployment engineers, and even students who are interested in practical applications of communication theory." Siavash M. Alamouti, Chief Technology Officer, Mobility Group, Intel "This is a very well-written, easy-to-follow, and comprehensive treatment of WiMAX. It should be of great interest." Dr. Reinaldo Valenzuela, Director of Wireless Research, Bell Labs "Fundamentals of WiMAX is a comprehensive guide to WiMAX from both industry and academic viewpoints, which is an unusual accomplishment. I recommend it to anyone who is curious about this exciting new standard." Dr. Teresa Meng, Professor, Stanford University, Founder and Director, Atheros Communications "Andrews, Ghosh, and Muhamed have provided a clear, concise, and well-written text on 802.16e/WiMAX. The book provides both the breadth and depth to make sense of the highly complicated 802.16e standard. I would recommend this book to both development engineers and technical managers who want an understating of WiMAX and insight into 4G modems in general." Paul Struhsaker, VP of Engineering, Chipset platforms, Motorola Mobile Device Business Unit, former vice chair of IEEE 802.16 working group "Fundamentals of WiMAX is written in an easy-to-understand tutorial fashion. The chapter on multiple antenna techniques is a very clear summary of this important technology and nicely organizes the vast number of different proposed techniques into a simple-to-understand framework." Dr. Ender Ayanoglu, Professor, University of California, Irvine, Editor-in-Chief, IEEE Transactions on Communications "Fundamentals of WiMAX is a comprehensive examination of the 802.16/WiMAX standard and discusses how to design, develop, and deploy equipment for this wireless communication standard. It provides both insightful overviews for those wanting to know what WiMAX is about and comprehensive, in-depth chapters on technical details of the standard, including the coding and modulation, signal processing methods, Multiple-Input Multiple-Output (MIMO) channels, medium access control, mobility issues, link-layer performance, and system-level performance." Dr. Mark C. Reed, Principal Researcher, National ICT Australia, Adjunct Associate Professor, Australian National University "This book is an excellent resourc...

Fundamentals of LTE

Abstract: The Definitive Guide to LTE Technology Long-Term Evolution (LTE) is the next step in the GSM evolutionary path beyond 3G technology, and it is strongly positioned to be the dominant global standard for 4G cellular networks. LTE also represents the first generation of cellular networks to be based on a flat IP architecture and is designed to seamlessly support a variety of different services, such as broadband data, voice, and multicast video. Its design incorporates many of the key innovations of digital communication, such as MIMO (multiple input multiple output) and OFDMA (orthogonal frequency division multiple access), that mandate new skills to plan, build, and deploy an LTE network. In Fundamentals of LTE, four leading experts from academia and industry explain the technical foundations of LTE in a tutorial style providing a comprehensive overview of the standards. Following the same approach that made their recent Fundamentals of WiMAX successful, the authors offer a complete framework for understanding and evaluating LTE. Topics includeCellular wireless history and evolution: Technical advances, market drivers, and foundational networking and communications technologiesMulticarrier modulation theory and practice: OFDM system design, peak-to-average power ratios, and SC-FDE solutionsFrequency Domain Multiple Access: OFDMA downlinks, SC-FDMA uplinks, resource allocation, and LTE-specific implementationMultiple antenna techniques and tradeoffs: spatial diversity, interference cancellation, spatial multiplexing, and multiuser/networked MIMOLTE standard overview: air interface protocol, channel structure, and physical layersDownlink and uplink transport channel processing: channel encoding, modulation mapping, Hybrid ARQ, multi-antenna processing, and morePhysical/MAC layer procedures and scheduling: channel-aware scheduling, closed/open-loop multi-antenna processing, and morePacket flow, radio resource, and mobility management: RLC, PDCP, RRM, and LTE radio access network mobility/handoff procedures

Method and apparatus for managing voicemail messages

Abstract: An apparatus (100, 200) and method are disclosed for managing voicemail messages. A system that incorporates teachings of the present disclosure may include, for example, a voicemail system (100) having a communications interface (110) and a controller (102) for managing operations of the communications interface. The controller is programmed to store (310) voicemail messages corresponding to a communication device (102), transmit (316) a log of the voicemail messages to the communication device, and receive (318) from the communication device a request to delete a voicemail message selectively chosen from a user interface corresponding to the voicemail log. The present disclosure further describes embodiments for the communication device.

What Will 5G Be

Abstract: What will 5G be? What it will not be is an incremental advance on 4G. The previous four generations of cellular technology have each been a major paradigm shift that has broken backward compatibility. Indeed, 5G will need to be a paradigm shift that includes very high carrier frequencies with massive bandwidths, extreme base station and device densities, and unprecedented numbers of antennas. However, unlike the previous four generations, it will also be highly integrative: tying any new 5G air interface and spectrum together with LTE and WiFi to provide universal high-rate coverage and a seamless user experience. To support this, the core network will also have to reach unprecedented levels of flexibility and intelligence, spectrum regulation will need to be rethought and improved, and energy and cost efficiencies will become even more critical considerations. This paper discusses all of these topics, identifying key challenges for future research and preliminary 5G standardization activities, while providing a comprehensive overview of the current literature, and in particular of the papers appearing in this special issue.

A Tractable Approach to Coverage and Rate in Cellular Networks

Abstract: Cellular networks are usually modeled by placing the base stations on a grid, with mobile users either randomly scattered or placed deterministically. These models have been used extensively but suffer from being both highly idealized and not very tractable, so complex system-level simulations are used to evaluate coverage/outage probability and rate. More tractable models have long been desirable. We develop new general models for the multi-cell signal-to-interference-plus-noise ratio (SINR) using stochastic geometry. Under very general assumptions, the resulting expressions for the downlink SINR CCDF (equivalent to the coverage probability) involve quickly computable integrals, and in some practical special cases can be simplified to common integrals (e.g., the Q-function) or even to simple closed-form expressions. We also derive the mean rate, and then the coverage gain (and mean rate loss) from static frequency reuse. We compare our coverage predictions to the grid model and an actual base station deployment, and observe that the proposed model is pessimistic (a lower bound on coverage) whereas the grid model is optimistic, and that both are about equally accurate. In addition to being more tractable, the proposed model may better capture the increasingly opportunistic and dense placement of base stations in future networks.

Femtocell networks: a survey

Abstract: The surest way to increase the system capacity of a wireless link is by getting the transmitter and receiver closer to each other, which creates the dual benefits of higher-quality links and more spatial reuse. In a network with nomadic users, this inevitably involves deploying more infrastructure, typically in the form of microcells, hot spots, distributed antennas, or relays. A less expensive alternative is the recent concept of femtocells - also called home base stations - which are data access points installed by home users to get better indoor voice and data coverage. In this article we overview the technical and business arguments for femtocells and describe the state of the art on each front. We also describe the technical challenges facing femtocell networks and give some preliminary ideas for how to overcome them.

A Survey of 5G Network: Architecture and Emerging Technologies

Abstract: In the near future, i.e., beyond 4G, some of the prime objectives or demands that need to be addressed are increased capacity, improved data rate, decreased latency, and better quality of service. To meet these demands, drastic improvements need to be made in cellular network architecture. This paper presents the results of a detailed survey on the fifth generation (5G) cellular network architecture and some of the key emerging technologies that are helpful in improving the architecture and meeting the demands of users. In this detailed survey, the prime focus is on the 5G cellular network architecture, massive multiple input multiple output technology, and device-to-device communication (D2D). Along with this, some of the emerging technologies that are addressed in this paper include interference management, spectrum sharing with cognitive radio, ultra-dense networks, multi-radio access technology association, full duplex radios, millimeter wave solutions for 5G cellular networks, and cloud technologies for 5G radio access networks and software defined networks. In this paper, a general probable 5G cellular network architecture is proposed, which shows that D2D, small cell access points, network cloud, and the Internet of Things can be a part of 5G cellular network architecture. A detailed survey is included regarding current research projects being conducted in different countries by research groups and institutions that are working on 5G technologies.

Location-based services

Abstract: Provided herein are methods and systems relating to location-based services such as social networking, providing demographic information, tracking mobile devices, providing business information, providing an adaptable user interface, remotely effecting a change on a portable electronic device, providing a geofence, outputting location-based information on a mobile device, varying transmissions to and from a mobile device, providing location-based alerts, verifying transactions and tailoring information to the behavior of a user.