Document Type

Closed Project

Publication Date

Fall 2003

Instructor

Dundar Kocaoglu

Course Title

Engineering and Technology Management

Course Number

EMGT 520/620

Abstract

The concept of cellular communications has been around for over fifty years but commercial implementation has only taken place in the last 20 years. The last 10 years have seen an almost exponential growth in the number of users worldwide, estimates are not I the millions but in billions. So how does this old technology hold up? It does so by innovation. All current and planned future technologies build upon the first and subsequent ones. What is interesting that despite having a common core mo st are incompatible with each other. The basic concept of cellular phones began in 1947, when researchers looked at crude mobile (car) phones and realized that by using smell cells (range of service area) with frequency reuse they could increase the traffic capacity if mobile phones substantially. However at that time, the technology to do so was nonexistent. Devised in the late 1970s to early 1980s, analog systems have been revised somewhat since that time and operate in the 800-MHz band. Most newer wireless phones and networks use digital technology. In digital, the analog voice signal is converted into binary code and transmitted as a series of on and off transmissions. There are three main digital wireless technologies, CDMA, TDMA and GSM. The demand from wireless communication technologies increases, so do the number of subscribers for wireless services. People are using their phones not only for communication but for entertainment, sending email, taking/sending digital picture and using GPS positioning. In the future the wireless networks will be asked to do more. 3G technology is the solution that fit this situation. The mobile telephone industry can be classified as an open system, due to the various different technologies involved that are in constant interaction with each other. The interactions between the technology providers determine the way the technology evolves. The telephone market mainly stands on four legs. The first of these four are the manufacturers, who make the handsets as well as the infrastructure equipment, such as switches and transmission apparatus. Then there are the network operators, also called service providers; these are companies that provide phone service to handset users. Third are platform vendors, which supply software environments, known as platforms, on which the handset's software stack is based. Also important are the application developers, who create applications that can be installed in handsets, such as games, image processing, basic PDA functions, and currency conversion.

Rights

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Comments

This project is only available to students, staff, and faculty of Portland State University

Persistent Identifier

http://archives.pdx.edu/ds/psu/23526

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