Reservation-based multiple access with variable frame length having flexible adaptability to traffic pattern

In this paper, we propose three extended reservation-based multiple access protocols with variable frame length (RMAV) in order to adapt to traffic variation more flexibly. At first, we propose model 1 of the extended RMAV in which the frame length can increase in the next frame as many slots as the terminal needs, while in the conventional RMAV the frame length increases one slot in the next frame. It is shown by computer simulation that the proposed model 1 can attain lower mean message delay and more rapid convergence speed than the conventional RMAV. Next, we propose model 2 of the extended RMAV, which has the function of supporting prioritized traffic and satisfies the different quality of service by using the variable maximum of the slots R_max,i that the terminal of class i can reserve in one frame. It is shown by numerical analysis and computer simulation that the performance of the higher priority class can surpass that of the lower priority class. Further, to make the reservation more efficiently, we propose model 3 of the extended RMAV, which uses minislots for reservation. It is shown by computer simulation that model 3 can reduce message delay compared to model 1.