Performance analysis of priority-dependent slotted nonpersistent CSMA with an adaptive array

In radio communication it is desirable to provide priority functions in order to process traffic with various quality requirements and to deal with multimedia technologies in the future. In the studies until the present, however, the packets were handled on an equal basis and traffic with priority was not considered. This article intends to handle traffic with priority and proposes to provide a priority function for a slotted nonpersistent CSMA system with an adaptive array. In the proposed system, two classes, 1 and 2, with different priorities are considered. The transmission start time for the packet of class 1 is arranged before the packet of class 2, so that the adaptive array can receive the packet of class 1 with priority. The throughput and the average number of transmissions in the proposed system are evaluated by theoretical analysis and computer simulation. As a result it is seen that the throughput and average number of transmissions are realized according to the priorities, without reducing the total throughput of class 1 and class 2.