Radio Frequency Assignment


Book Description

The frequency assignment problem involves the assignment of discrete channels to the transmitters of a radio network. Frequency separation is necessary to avoid interference by other transmitters to the signal received from the wanted transmitter at the reception points. Unnecessary separation causes an excess requirement for spectrum. Good assignments minimise interference and the spectrum required. Some different variations of the problem are reviewed in this book. We mainly consider the "Fixed Spectrum Problem", where there is a fixed available spectrum of frequencies and the aim is to minimise interference. For this problem we analise the "Binary Constraints Model", where only interference from a single transmitter at a time is considered, and the more realistic "Multiple Interference Model", where interferences from more than one transmitter are considered at the same moment. In particular, we analyse some Integer Programming formulation for the binary constraints model to understand whether they can be suitable for developing lower bounds. Some new algorithms for the multiple interference model are finally discussed.













Models and Solution Techniques for Frequency Assignment Problems


Book Description

Abstract: "Wireless communication is used in many different situations such as mobile telephony, radio and TV broadcasting, satellite communication, and military operations. In each of these situations a frequency assignment problem arises with application specific characteristics. Researchers have developed different modeling ideas for each of the features of the problem, such as the handling of interference among radio signals, the availability of frequencies, and the optimization criterion. This survey gives an overview of the models and methods that the literature provides on the topic. We present a broad description of the practical settings in which frequency assignment is applied. We also present a classification of the different models and formulations described in the literature, such that the common features of the models are emphasized. The solution methods are divided in two parts. Optimization and lower bounding techniques on the one hand, and heuristic search techniques on the other hand. The literature is classified according to the used methods. Again, we emphasize the common features, used in the different papers. The quality of the solution methods is compared, whenever possible, on publicly available benchmark instances."




Frequency Assignment and Network Planning for Digital Terrestrial Broadcasting Systems


Book Description

Frequency Assignment and Network Planning for Digital Terrestrial Broadcasting Systems focuses on Digital Audio Broadcasting and Digital Video Broadcasting. The author provides a concise introduction to the subject and presents principles, concepts and commonly accepted methods used in the planning process. The frequency assignment material focuses on allotment planning while network planning is dealt with mainly from a network optimization perspective. All methods introduced and mathematical tools presented are fully explained. General concepts are illustrated with the help of several planning scenarios both for frequency assignment and network planning. Frequency assignment and network planning are vital issues throughout most of Europe and North America as a direct consequence of the increasing demand for digital communication systems.




Cross-Layer Resource Allocation in Cognitive Radio Networks: Models, Algorithms, and Applications


Book Description

This book is about cognitive radio (CR), a revolution in radio technology and an enabling technology for dynamic spectrum access. Due to the unique characteristics of the wireless networks, it is essential to address the approach of multiple layers (e.g., physical, link, and network) to maximize the network performance. The formulation of this cross-layer problem is usually complicated and challenging, while wireless resource allocation is a vital way to handle the race condition of the limited wireless resources. However, given the intrinsic characteristics of cognitive radio networks (CRN), none of the existing analytical approach could be a direct fit. Therefore, innovative theoretical results, along with the corresponding mathematical techniques, are necessary. In this book, we aim to develop some novel algorithmic design and optimization techniques that provide optimal or near-optimal solutions. Although cross-layer design has been introduced to CRN for many years, there are rarely any books for researchers, engineers, and students, from the engineering perspective. From one hand, most of the existing books primarily focus on the mathematical and economic aspects, which are considerably different from the engineering. On the other hand, all of the books mainly aim to system optimization or control techniques, while the cross-layer algorithm design in the distributed environment is usually ignored. As the result, there is an urgent demand for a reference source, which can provide complete information on how to fully adopt cross-layer resource allocation to the CRN. In this regard, this book not only focuses on the description of the main aspects of cross-layer resource allocation over CRN, but also provides a review of the application solutions. In a nutshell, it provides a specific treatment of cross-layer design in CRN. The topics range from the basic concepts of cross-layer resource allocation, to the state-of-the-art analyses, modelings, and optimizations for CRN.




Formal Methods in Manufacturing


Book Description

Illustrated with real-life manufacturing examples, Formal Methods in Manufacturing provides state-of-the-art solutions to common problems in manufacturing systems. Assuming some knowledge of discrete event systems theory, the book first delivers a detailed introduction to the most important formalisms used for the modeling, analysis, and control of manufacturing systems (including Petri nets, automata, and max-plus algebra), explaining the advantages of each formal method. It then employs the different formalisms to solve specific problems taken from today’s industrial world, such as modeling and simulation, supervisory control (including deadlock prevention) in a distributed and/or decentralized environment, performance evaluation (including scheduling and optimization), fault diagnosis and diagnosability analysis, and reconfiguration. Containing chapters written by leading experts in their respective fields, Formal Methods in Manufacturing helps researchers and application engineers handle fundamental principles and deal with typical quality goals in the design and operation of manufacturing systems.