Delay Analysis of Random Scheduling and Round Robin in Small Cell Networks

TL;DR

This paper compares delay performance of random scheduling and round robin in small cell networks, showing RR's superiority especially under heavy traffic and its suitability for IoT networks.

Contribution

It provides a stochastic geometry and queuing theory-based analysis of delay, demonstrating RR's advantages over RS in small cell networks.

Findings

RR has lower mean delay than RS regardless of traffic.

RR supports more UEs under the same delay outage probability.

RR is more effective in heavy traffic conditions.

Abstract

We analyze the delay performance of small cell networks operating under random scheduling (RS) and round robin (RR) protocols. Based on stochastic geometry and queuing theory, we derive accurate and tractable expressions for the distribution of mean delay, which accounts for the impact of random traffic arrivals, queuing interactions, and failed packet retransmissions. Our analysis asserts that RR outperforms RS in terms of mean delay, regardless of traffic statistic. Moreover, the gain from RR is more pronounced in the presence of heavy traffic, which confirms the importance of accounting fairness in the design of scheduling policy. We also find that constrained on the same delay outage probability, RR is able to support more user equipments (UEs) than that of RS, demonstrating it as an appropriate candidate for the traffic scheduling policy of internet-of-things (IoT) network.