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Upper bound and approximation of random access throughput over chase combining HARQ

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

Details

Original languageEnglish
Title of host publication2017 9th International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT)
PublisherIEEE
Pages143-147
Number of pages5
ISBN (Electronic)978-1-5386-3435-6
DOIs
Publication statusPublished - 1 Nov 2017
Publication typeA4 Article in a conference publication
EventInternational Conference on Ultra Modern Telecommunications and Control Systems and Workshops -
Duration: 1 Jan 1900 → …

Publication series

Name
ISSN (Print)2157-023X

Conference

ConferenceInternational Conference on Ultra Modern Telecommunications and Control Systems and Workshops
Period1/01/00 → …

Abstract

Massive MTC (mMTC) scenarios featuring a tremendous number of devices challenge the conventional multiple access protocols, which are mostly based on classic ALOHA algorithms known for their instability at higher loads. While numerous modifications of ALOHA adopt the unrealistic assumption on the fixed number of contending uses, we in this paper study a model where a random number of users activate within the slot. In particular, we explore a modification of ALOHA augmented with the Chase combining HARQ (HARQ-CC) and derive an approximation for and a simple upper bound on the system throughput. While the former perfectly matches the corresponding simulation results for the SNR of up to 10dB, the latter constitutes an increasingly tight limit as the SNR grows. Based on both analytical considerations, the resulting system throughput may be significantly improved with the optimal choice of the transmission probability and code spectral efficiency.

Keywords

  • Decoding, Interference, Nickel, Random variables, Signal to noise ratio, Throughput, Upper bound, ALOHA, Chase combining, Hybrid-ARQ, Random multiple access, system throughput, upper bound

Publication forum classification