Non-Orthogonal Contention-Based Access for URLLC Devices with Frequency Diversity

Research output: Chapter in Book/Report/Conference proceedingConference contributionScientificpeer-review

Researchers

Research units

  • Aalborg University

Abstract

We study coded multichannel random access schemes for ultra-reliable low-latency uplink transmissions. We concentrate on non-orthogonal access in the frequency domain, where users transmit over multiple orthogonal subchannels and inter-user collisions limit the available diversity. Two different models for contention-based random access over Rayleigh fading resources are investigated. First, a collision model is considered, in which the packet is replicated onto K available resources, K' ≤ K of which are received without collision, and treated as diversity branches by a maximum-ratio combining (MRC) receiver. The resulting diversity degree K' depends on the arrival process and coding strategy. In the second model, the slots subject to collisions are also used for MRC, such that the number of diversity branches K is constant, but the resulting combined signal is affected by multiple access interference. In both models, the performance of random and deterministic repetition coding is compared. The results show that the deterministic coding approach can lead to a significantly superior performance when the arrival rate of the intermittent URLLC transmissions is low.

Details

Original languageEnglish
Title of host publication2019 IEEE 20th International Workshop on Signal Processing Advances in Wireless Communications, SPAWC 2019
Publication statusPublished - 1 Jul 2019
MoE publication typeA4 Article in a conference publication
EventIEEE International Workshop on Signal Processing Advances in Wireless Communications - Cannes, France
Duration: 2 Jul 20195 Jul 2019
Conference number: 20

Publication series

NameIEEE International Workshop on Signal Processing Advances in Wireless Communications
ISSN (Print)2325-3789
ISSN (Electronic)1948-3252

Workshop

WorkshopIEEE International Workshop on Signal Processing Advances in Wireless Communications
Abbreviated titleSPAWC
CountryFrance
CityCannes
Period02/07/201905/07/2019

    Research areas

  • coded random access, grant-free, MRC, URLLC

ID: 37223555