Stability of the dual group priority-based CDMA ALOHA system: the selection of control parameters

In the deferred first transmission ALOHA system, packets requesting service are first sent to a backlogged state from where they retransmit. This is the same concept used for the dual group priority-based CDMA ALOHA system. The actual number of backlogged users in a given time slot is not known before hand. Therefore, there are two important parameters in the system, i.e. the estimated number and the real number of backlogged users. This paper expands on work done in determining the control parameters for conventional slotted ALOHA systems. Control parameters are derived to ensure that the estimated number of backlogged users closely tracks the real number, eventually clearing all the backlogged users from the system.