|dc.identifier.citation||Wang, Y. 2018. Energy Efficient Channel Access Mechanism for IEEE 802.11ah based Networks. Queen Mary University of London||en_US
|dc.description.abstract||IEEE 802.11ah is designed to support battery powered devices that are required to serve
for several years in the Internet of Things networks. The Restricted Access Window
(RAW) has been introduced in IEEE 802.11ah to address the scalability of thousands of
densely deployed devices. As the RAW sizes entail the consumed energy to support the
transmitting devices in the network, hence the control mechanism for RAW should be
carefully devised for improving the overall energy e ciency of IEEE 802.11ah.
This thesis presents a two-stage adaptive RAW scheme for IEEE 802.11ah to optimise
the energy efficiency of massive channel access and transmission in the uplink communications
for highly dense networks. The proposed scheme adaptively controls the RAW
sizes and device transmission access by taking into account the number of devices per
RAW, retransmission mechanism, harvested-energy and prioritised access. The scheme
has four completely novel control blocks:
RAW size control that adaptively adjusts the RAW sizes according to different
number of devices and application types in the networks.
RAW retransmission control that improves the channel utilisation by retransmitting
the collided packets at the subsequent slot in the same RAW.
Harvested-energy powered access control that adjusts the RAW sizes with the consideration
of the uncertain amount of harvested-energy in each device and channel
Priority-aware channel access control that reduces the collisions of high-priority
packets in the time-critical networks.
The performance of the proposed controls is evaluated in Matlab under different net
work scenarios. Simulation results show that the proposed controls improve the network
performances in terms of energy efficiency, packet delivery ratio and delay as compared
to the existing window control.||en_US
|dc.publisher||Queen Mary University of London||en_US
|dc.rights||The copyright of this thesis rests with the author and no quotation from it or information derived from it may be published without the prior written consent of the author||
|dc.subject||Electronic Engineering and Computer Science||en_US
|dc.subject||Internet of Things||en_US
|dc.subject||Restricted Access Window||en_US
|dc.title||Energy Efficient Channel Access Mechanism for IEEE 802.11ah based Networks||en_US