An Algorithm for Improving Throughput Guarantee of Topology-Transparent MAC Scheduling Strategy

Chaonong Xu

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DOI: 10.4236/wsn.2010.210096                

Abstract

Topology-transparent MAC scheduling strategies nowadays are all based on combinatorial design. To get throughput guarantee, a cover-free set is output as scheduling strategy of network. In this paper, we aim to modify the cover-free set so that better throughput can be guaranteed. At the first step, the redundant slot of the cover-free set is proposed and found to have negative influence on the minimal guaranteed throughput. Second, we prove that any subset of a cover-free set is still a cover-free set after its redundant slots were squashed out. Our algorithm chooses the subset which has the maximal number of redundant slots, squashes all of its redundant slots, and then designates it as the network scheduling strategy. Therefore, better through- put can be guaranteed if the squashed subset is adopted as network scheduling strategy. For any topology- transparent node scheduling strategy, both the increased minimal throughput and decreased maximal transmission delay can be gotten by just using our algorithm as an extra accessory.

Keywords

MAC Scheduling, Qos, Combinatorial Design, Superimposed Code, Cover-Free Set

Conflicts of Interest

The authors declare no conflicts of interest.

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