On the performance of packet aggregation in IEEE 802.11ac MU-MIMO WLANs

Abstract

Multi-user spatial multiplexing combined with packet aggregation can significantly increase the performance of Wireless Local Area Networks (WLANs). In this letter, we present and evaluate a simple technique to perform packet aggregation in IEEE 802.11ac MU-MIMO (Multi-user Multiple Input Multiple Output) WLANs. Results show that in non-saturation conditions both the number of active stations (STAs) and the queue size have a significant impact on the system performance. If the number of STAs is excessively high, the heterogeneity of destinations in the packets contained in the queue makes it difficult to take full advantage of packet aggregation. This effect can be alleviated by increasing the queue size, which increases the chances of scheduling a large number of packets at each transmission, hence improving the system throughput at the cost of a higher delay.

The authors want to express their gratitude to the anonymous reviewers and the editor for their helpful comments. This work has been partially supported by the Spanish Government under projects TEC2008-06055 (Plan Nacional I+D), CSD2008-00010 (Consolider-Ingenio Program), the Catalan Government (SGR2009#00617) and WINEMO IC0906 COST Action.