Using power priorities to improve slotted ALOHA in wireless networks with QoS guarantees

A fundamental part of a wireless system is the MAC protocol, whose main goal is to let the users quickly and orderly gain access to the needed bandwidth to transmit their information. The main problem in wireless communications is to overcome the disadvantage of the hostile characteristics presented by the radio channel. This paper deals with the proposal of a retransmission algorithm based on power priorities (RAPP), to be used along with S-ALOHA for the retransmission of the request packets sent by remote terminals to a base station (BS) in a WATM network. WATM is used in this work as a test platform, but RAPP is general enough to be applied in other scenarios as well. The performance of RAPP is analyzed and compared with that of the binary exponential retransmission algorithm, highlighting the advantages presented by RAPP in a WATM environment.