Satisfying Strict Deadlines for Cellular Internet of Things through
Hybrid Multiple Access
Abstract
Latency-constrained aspects of cellular Internet of Things (IoT)
applications rely on Ultra-Reliable and Low Latency Communications
(URLLC) which highlight research on satisfying strict deadlines. In this
study, we address the problem of latency constrained communications with
strict deadlines under average power constraint using Hybrid Multiple
Access (MA) which consists of both Orthogonal MA (OMA) and power domain
Non-Orthogonal MA (NOMA) as transmission scheme options. We aim to
maximize the timely throughput, which represents the average number of
successfully transmitted packets before deadline expiration, where
expired packets still waiting in the buffer are dropped. We use Lyapunov
stochastic optimization methods to develop a dynamic power assignment
algorithm for minimizing the packet drop rate while satisfying time
average power constraints. Numerical results show that Hybrid MA
improves the timely throughput compared to conventional OMA by up to
46% and on the average by more than 21% while satisfying average power
constraints.