Two tier adaptive random access protocol

摘要

A communication system has a plurality of stations which communicate data in a data frame having a plurality of slots including data slots DS, new message minislots MS0, and/or old message minislots MS1. A master station determines new and old message range parameters R0 and R1 which are based upon colliding reservation requests in a data frame. The master station determines the new and old message minislots MS0 and MS1 according to reservation request activity. The master station transmits the new and old message range parameters R0 and R1, and a MAP defining the new and old message minislots MS0 and MS1 to a plurality of slave stations. Each slave station independently determines transmission parameters N0 and N1 within the corresponding new and old message range parameters R0 and R1. Each slave station transmits a new reservation request to the master station if its transmission parameter N0 corresponds to one of the new message minislots MS0 and transmits an old reservation request to the master station if its transmission parameter N1 corresponds to one of the old message minislots MS1.