Performance Analysis of Unslotted CSMA/CA Based On Channel Dedicated For VLC Networks

Abstract

Due to the advantages of rich frequency band, security and confidentiality, visible light communication technology is gradually regarded as an effective solution to the exhaustion of radio frequency(RF) spectrum resources. This paper designs a channel dedicated unslotted CSMA/CA algorithm, and analyzes the impact of collision probability, retransmission times, access failure probability, and normalized throughput on the network performance when transmitting non-real-time traffic. The results show that the collision probability is inversely proportional to the terminal payload packet arrival rate λ, as the number of terminals increases, the saturation collision probability of λ =1 is 0.501 and λ =2 is 0.382, The access failure probability increases nonlinearly with the increasing terminals numbers, but when the number of terminals exceeds 5, the access failure probability increases sharply, the normalized throughput decreases continuously and tends to saturate when the total channel traffic reaches the physical limit of bandwidth.