Back to graduate studentsA Study of Indoor radio Propagation Channel Characteristics by Simulation
by
Naser Movahhedinia
Ph D, 1995
Abstract
One of the recent issues in wireless communications is the ability to support multimedia applications in a broadband ATM platform. In such a system, remote terminals may be capable of producing broadband, real-time traffic such as variable bit rate video or bursty instantaneous file transfers. Compared to wired medium, the bandwidth in wireless medium is more expensive, therefore, an efficient bandwidth management procedure is required for the wireless broadband ATM networks. To obtain the required performance, the effects of radio channel behavior as well as the traffic heterogeneity have to be considered in the bandwidth control procedure. As such, the simple conventional multiple access protocols may not offer adequate flexibility and performance. The scope of this thesis is to present a proper bandwidth assignment regulation, meditating on the interplay of the radio channel characteristics, the traffic statistical parameters and the traffic Quality of Service (QoS) requirements. Starting from the simple non-limited polling scheme, the performance of the multiple access protocol is improved, with an analytical backup, to a graceful method which utilizes all the stated parameters. The investigation produced two multiple access methods in which the base station visits the remote terminals in a non-uniform cyclic fashion. The basic properties of these two methods which are called "non-uniform polling" and "non-uniform slot reservation" are as follow:
The bandwidth management is further completed by presenting a virtual bandwidth for a given type of traffic, based on which the admission control procedure is performed. The performance of the non-uniform polling and the non-uniform slot reservations is evaluated and compared with some other techniques by simulations.