Outage-Optimal Power Allocation for Hybrid ARQ with Incremental Redundancy
2011 (English)In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 10, no 7, 2069-2074 p.Article in journal (Refereed) Published
We consider the optimization of power in incremental redundancy (IR) based hybrid automatic repeat request (HARQ) schemes when the maximum number of(re)transmissions is fixed. We formulate two optimization problems:(i) minimizing the packet drop probability (PDP) undera total average transmit power constraint, and (ii) minimizingthe average transmit power under a fixed PDP constraint.We consider in detail the special case of only two allowed transmissions, and we prove that the two optimization problems are equivalent. For this special case, we also provide a sub-optimal root- finding solution and compare its performance with the optimal solution obtained through an exhaustive search.The results show that the optimal power allocation can provide significant gains over the equal power solution in terms of average transmit power spent. The performance of the proposed root-finding solution is practically the same as that of the optimal solution.
Place, publisher, year, edition, pages
IEEE , 2011. Vol. 10, no 7, 2069-2074 p.
Hybrid ARQ, incremental redundancy, optimal power allocation, outage probability.
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-67132DOI: 10.1109/TWC.2011.041311.101978ISI: 000293685400010OAI: oai:DiVA.org:liu-67132DiVA: diva2:407596
Funding Agencies|Swedish Research Council (VR)||Swedish Foundation for Strategic Research (SSF)||ELLIIT||Knut and Alice Wallenberg Foundation||2011-03-312011-03-312013-09-11Bibliographically approved