Authors:
Tomokazu Moriyama
;
Ryo Yamamoto
;
Satoshi Ohzahata
and
Toshihiko Kato
Affiliation:
University of Electro-Communications, Japan
Keyword(s):
IEEE 802.11ac WLAN, MU-MIMO, Frame Aggregation, Spatial Stream.
Related
Ontology
Subjects/Areas/Topics:
MIMO Systems and Techniques
;
Performance Analysis of Wireless Networks
;
Telecommunications
;
Wireless and Mobile Technologies
;
Wireless Information Networks and Systems
Abstract:
In order to improve the throughput over WLAN, the IEEE 802.11ac standard, which has been used recently,
introduces the frame aggregation and MU-MIMO (multi-user multiple-input and multiple-output)
mechanisms. The frame aggregation concatenates multiple data frames in one MAC data unit. MU-MIMO
provides SDMA (space division multiple access), which allows multiple STAs (stations) to share space
resources. In an 802.11ac WLAN, MU-MIMO is used in the downlink data transfer in a way that data frames
to multiple STAs are aggregated separately and transmitted at the same time. When traffic loads to individual
STAs are different, however, it is possible that there is a waste in space and time resources. In order to avoid
this waste, several methods to control the frame aggregation size for MU-MIMO are proposed. Those methods
focus mainly on increasing the channel utilization, and so they have a problem that there is a large delay in
transmitting an aggregated data unit. In this pape
r, we propose a new method to determine the frame
aggregation size considering both channel utilization and delay data frames suffer from in transmission
queues. A performance evaluation result shows that our method provides high channel efficiency with keeping
transmission delay in a relatively small value.
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