Occupancy Distributions of Homogeneous Queueing Systems Under Opportunistic Scheduling

摘要

This paper analyzes opportunistic schemes for transmission scheduling from one of $n$ homogeneous queues whose channel states fluctuate independently. Considered schemes consist of an LCQ policy that transmits from a longest connected queue in the entire system, and its low-complexity variant ${hbox{LCQ}} (d)$ that transmits from a longest queue within a randomly chosen subset of $dge 1$ connected queues. A Markovian model is studied where mean packet transmission time is $n^{-1}$ and packet arrival rate is $lambda then the maximum queue length is 1 and the system occupancy reduces to $O(n/d)$. Numerical comparison of the obtained asymptotic mean packet delays suggests that LCQ and ${hbox{LCQ}} (d)$ may have comparable delay performance for moderate values of $n$ and $d$.