Medium access control and flow control method using an adaptive polling scheme for wireless ATM Network

Abstract

In this thesis, we propose a medium access control method for wireless ATM networks. Recent years have seen the deployment of a large number of multiple access protocols for the integrated wireless networks, whether a simple integration between voice and data for a wireless ATM network. However, with these protocols, the MT suffers from a serious reservation access delay at heavy load which does not suit the QoS requirement of the stringent ATM services. In addition, the decision of the frame length is difficult for VBR traffic which change cell transmission rate dynamically. A possible method to overcome this difficulty is to use the bandwidth reservation request from a virtual source located at BS instead of it from the real source (i.e., MT). This method does not need reservation access delay, simplifies the MT``s protocol overhead, and can work without the (super) frame structure. Our method aims to satisfy the delay constraint of the various wireless ATM connections to guarantee QoS and simplify the protocol overhead on mobile terminals. The virtual sources in the base station reserve bandwidth instead of the real sources in the mobile terminals. The virtual sources generate reservation requests (tokens), which are served with priority according to the traffic classes and the delay constraints. We propose an adaptive method that controls the token generation rate to meet the delay constraints and effective bandwidth utilization.