Centralized random backoff for collision free wireless local area networks
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Date
04/07/2018Item status
Restricted AccessEmbargo end date
04/07/2019Author
Kim, Jinho D.
Metadata
Abstract
Over the past few decades, wireless local area networks (WLANs) have been
widely deployed for data communication in indoor environments such as offices,
houses, and airports. In order to fairly and efficiently use the unlicensed frequency
band that Wi-Fi devices share, the devices follow a set of channel access rules,
which is called a wireless medium access control (MAC) protocol. It is known that
wireless devices following the 802.11 standard MAC protocol, i.e. the distributed
coordination function (DCF), suffer from packet collisions when multiple nodes
simultaneously transmit. This significantly degrades the throughput performance.
Recently, several studies have reported access techniques to reduce the number
of packet collisions and to achieve a collision free WLAN. Although these studies
have shown that the number of collisions can be reduced to zero in a simple
way, there have been a couple of remaining issues to solve, such as dynamic
parameter adjustment and fairness to legacy DCF nodes in terms of channel
access opportunity.
Recently, In-Band Full Duplex (IBFD) communication has received much
attention, because it has significant potential to improve the communication
capacity of a radio band. IBFD means that a node can simultaneously transmit
one signal and receive another signal in the same band at the same time. In
order to maximize the performance of IBFD communication capability and to
fairly share access to the wireless medium among distributed devices in WLANs,
a number of IBFD MAC protocols have been proposed. However, little attention
has been paid to fairness issues between half duplex nodes (i.e. nodes that can
either transmit or receive but not both simultaneously in one time-frequency
resource block) and IBFD capable nodes in the presence of the hidden node
problem.