EFFICIENCY EVALUATION OF SCHEDULING ALGORITHMS FOR DELAY-SENSITIVE TRAFFIC IN OFDM DOWNLINK

Abstract

Introduction: Common introduction of industrial control systems based on wireless networks leads to the emergence of a new way of using wireless networks, called the Industrial Internet of Things (IIoT). This framework assumes a large but finite number of users for which you have to provide the transmission of short messages with low delay and limited delay variation. Purpose: Efficiency evaluation of resource allocation algorithms for delay-sensitive traffic in a downlink OFDM channel. Methods: A n OFDM system is presented as a set of M/G/1 queuing systems. A convex optimization problem is introduced, whose solution determines the lower boundary of the average delay of message transmission in delay-sensitive traffic over the set of scheduling algorithms under study. Results: An algorithm is proposed for calculating the lower boundary of the average delay. This algorithm is fed by system parameters: the average message size, the input flow intensity, and the average maximum throughput for each device connected to the base station. Based on these input parameters, the optimization problem is introduced and solved by a numerical method. The solution of the optimization problem determines the lower boundary of the average message transmission delay. Practical relevance : The obtained result can be used by system developers for plan ning and deploying OFDM networks . It can also serve as a reference when developing Ultra- Reliable and Low Latency Communication technology .