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Abstract
The increasing importance of portable computingltelecommunir. ations applications has motivated the studies on broadband wireless network technologies such as wireless ATM (Asynchronous Transfer Mode) or WATM. ATM is potentially capable of supporting all classes of traffic (e.g., voice, video, data) in one transmission and switching fabric technology. It promises to provide greater integration of capabilities and services, increased and more flexible access to the network, and more efficient and economical service. The services differ in the way they transmit data through the network by allocating different bandwidth as defined by the ATM forum. Depending on the application and the user’s needs, a suitable service is provided representing different Quality of Service (QoS). Orthogonal Frequency Division Multiplexing (OFDM) is especially suitable for high-speed communication due to its resistance to Inter Symbol Interference ISl. As communication systems increase their information transfer speed the time for each transmission necessary becomes shorter. Since the delay time caused by multipath remains constant, ISl becomes a limitation in high due rate communication OFDM avoids this problem by sending many low speed transmission simultaneously. In this thesis, a brief outline of the concepts of WA TM with its applications, services and the Medium Access Control (MAC) protocols proposed is given. The simulation is divided into three parts: The first part focuses on the physical layer and examines the effects of noise and mobility on a wireless channel. The second part includes choosing a particular network and analyzing the different QoS parameters for this network. The third part simulates an OFDM communication channel used to transmit different classes of traffic.