Centralized transmission probability control scheme for non-real-time traffic in wireless ATM networks

摘要

This article proposes a contention-based reservation medium access control protocol for transporting bursty traffic efficiently in wireless ATM networks. The proposed protocol is characterized by a contention-based transmission of the reservation request and a contention-free transmission of the bursty traffic. The design objective of the proposed protocol is to reduce the contention delay while maximizing the channel utilization. In order to reduce the collision of reservation request packets, the base station calculates and broadcasts the transmission permission probability of reservation request packets. The calculation of the transmission permission probability is based on the estimated load of reservation requests and the number of random access minislots. The wireless terminal, which has a bursty traffic, selects a random access minislot and transmits its reservation request packet with the received transmission permission probability. Based on the successfully received reservation packets, the scheduler allocates the uplink data slots to the wireless terminal. Simulation results are presented to show that the proposed protocol provides high channel utilization, and furthermore, maintains a constant delay performance in a heavy traffic environment.