Communication Subsystems for Emerging Wireless Technologies

The paper describes a multi-disciplinary design of modern communication systems. The design starts with the analysis of a system in order to define requirements on its individual components. The design exploits proper models of communication channels to adapt the systems to expected transmission conditions. Input filtering of signals both in the frequency domain and in the spatial domain is ensured by a properly designed antenna. Further signal processing (amplification and further filtering) is done by electronics circuits. Finally, signal processing techniques are applied to yield information about current properties of frequency spectrum and to distribute the transmission over free subcarrier channels

Issues and Challenges in Cataloguing Arabic Books in Malaysian Academic Libraries

Education in Library and Information Science is a requirement to become a librarian. There are a lot of syllabuses and subjects to concentrate on such as cataloguing and classification, information retrieval, knowledge management, and reference. Library as a centre of information has been developing year by year with various types of collections written and presented in many languages such as English, Arabic and Malay. The different languages come with different letters, words, pronunciations and characters. They can bring problems and challenges in cataloguing process including determining the access points, subject headings and call number. The objective of this study is to identify the challenges in cataloguing Arabic books for cataloguers in Malaysian academic libraries

Discovering Jewish Studies Collections in Academic Libraries: A Practical Guide

The U.S. colleges and universities offering non-sectarian educational programs in Jewish Studies rely on the support of their academic libraries for research materials and library services. For college libraries which use Library of Congress Classification scheme, it is a common practice to integrate studies resources into their general library collections. Since Jewish Studies sources span a vast number of subjects within all major disciplines, shelving integration leads to the dispersion of all relevant sources and such dispersion in turn leads to a variety of problems for library professionals and library users. For collection development librarians the problems range from lack of information about collection\u27s size, strengths or weaknesses, and for library users interested in browsing the collection, dispersion of subjects creates a major roadblock. This practical guide aims at providing a solution to such problems. By identifying all relevant Library of Congress call numbers and the corresponding Library of Congress subject headings, the guide offers a simplified access to Jewish Studies sources in general library collections. It is arranged by four major discipline: Arts & Humanities, Social Sciences, Sciences, and General Works & Bibliographies. Within each discipline, specific LC call number ranges and corresponding subjects are listed. The subjects are further subdivided and precisely identified. The guide will assist collection development librarians, library liaisons, grants and fundraising professionals and especially the Jewish Studies faculty and students, in identifying and locating relevant sources

Signal propagation in mobile communication systems

Tato práce popisuje základní princip funkce mobilních komunikačních systémů. Blíže jsou zde popsány systémy GSM, UMTS. Práce se zabývá zejména problematikou ztrát při šíření signálu, které nastávají mezi vysílačem a přijímačem. Popsány jsou situace, které mohou nastat při šíření signálu v různých prostředích. Dále jsou zde také uvedeny modely pro predikci ztrát šířením v prostředí indoor, outdoor, které jsou popsány a vysvětleny. Součástí této práce je také simulační program s grafickým uživatelským rozhraním, který podle vybraného modelu a vstupních parametrů vypočítá a graficky zobrazí hodnoty ztrát šířením.The aim of this thesis is to describe the basic principles and function of signal propagation in mobile communication systems. Closer look is taken at GSM and UMTS communication systems. The thesis deals especially with the problem of path losses, which occurs between transmitter and receiver. Possible propagation scenarios for cellular network are theoretically described. Also the propagation models for outdoor and indoor path loss prediction are described and simulated. The developed program estimates path loss and graphically represents the results of simulation for various model parameters, environments and scenarios.