무선 환경 하에서 Slotted ALOHA 방식의 다중채널 경쟁에 대한 지연시간분석

Abstract

Slotted ALOHA(S-ALOHA) is widely used in local wireless network. We analyze the performance of contention-based model in wireless LAN using S-ALOHA protocol. We analyze the performance of binary exponential backoff(BEB) algorithm under the slotted ALOHA protocol : whenever a node`s message which tries to reserve a channel is involved in a collision for the i th time, it chooses one of the next 2^i frames with equal probability an attempts the reservation again. We derive the expected access dealy and throughput which is defined as the expected number of messages that reserve a channel in a frame. A simulation study is performed to verify our method.