Throughput Maximization for Delay-Sensitive Random Access Communication

• Published in: IEEE transactions on wireless communications Vol. 18; no. 1; pp. 709 - 723
• Main Authors: Malak, Derya, Huang, Howard, Andrews, Jeffrey G.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.01.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Cellular communication; chase combining; Communication; Communications systems; Delay; Interference; latency; Machine-type communication; Optimization; Payloads; Random access; Receivers; Receivers & amplifiers; Resource allocation; Signal to noise ratio; single cell; Throughput; Time-frequency analysis; Wireless communication; Wireless communications; Wireless networks
• ISSN: 1536-1276; 1558-2248
• DOI: 10.1109/TWC.2018.2885295

Future 5G cellular networks supporting delay-sensitive, low-latency communications could employ random access communication to reduce the overhead compared to scheduled access techniques used in 4G networks. We consider a wireless communication system where multiple devices transmit payloads of a given fixed size in a random access fashion over shared radio resources to a common receiver. We allow retransmissions and assume Chase combining at the receiver. The radio resources are partitioned in the time and frequency dimensions, and we determine the optimal partition granularity to maximize throughput, subject to given constraints on latency and outage. In the regime of high and low signal-to-noise ratio (SNR), we derive explicit expressions for the granularity and throughput, first using a Shannon capacity approximation and then using finite block length analysis. Numerical results show that the throughput scaling results are applicable over a range of SNRs. The proposed analytical framework can provide insights for resource allocation strategies in reliable and delay-sensitive random access systems and in specific 5G use cases for massive, short packet uplink access.