Base station MAC with APRMA protocol for broadband multimedia ATM in micro/pico-cellular mobile networks

The concept for a wireless ATM access system that enables seamless mobile connectivity to the B-ISDN is presented. It is based on small, low cost and intelligent base stations running a medium access control (MAC) protocol using adaptive packet reservation multiple access (APRMA). Both the principles and the performance of this protocol are discussed. A channel efficiency of more than 70% and a mean cell transfer delay of less than 17 cells are obtained in the range of 1-50 simultaneously connected users even with bursty traffic. For this, the cell dropping rate is kept below 10^-9 when the mobile terminals use buffer lengths of only 200-300 cells. The different components of this access system are currently under implementation and the MAC unit has been successfully implemented for a 32 Mbit/s wireless channel supporting 25 Mbit/s ATM introducing only 22% of protocol overhead