Design and optimisation for next-generation wireless LANs
What we offer:
IEEE 802.11 denotes a set of Wireless LAN (WLAN) standards and is one of the most deployed wireless access technologies worldwide. Among the most prospective next generations of the technology are
- IEEE 802.11p, which is also known as WAVE (Wireless Access for the Vehicular Environment)
- IEEE 802.11n, where higher throughput is achieved using MIMO (multiple input, multiple output) technology
- IEEE 802.11e, the main advantage of which consists of implementation of Quality of Service (QoS),including packet bursting
The research of the London-based university submitting this offer is focused on the adaptive communication protocol design, performance analysis, modelling, simulation, optimisation and standardisation for the next-generation IEEE 802.11 WLANs as follows:
• The design of a new medium access control (MAC) layer scheme called Adaptive EDCA (AEDCA) that
extends the 802.11e EDCA (Enhanced Distributed Channel Access), by increasing the contention
window during deferring periods when the channel is busy, and by using an adaptive fast back-off mechanism when the channel is idle.
• An HCCA (HCF - Hybrid Coordination Function - Controlled Channel Access) reference scheduler was proposed in the 802.11e specification. The researchers have shown that this reference scheduling
algorithm is only efficient for flows with strict constant bit rate (CBR) characteristics. However, a lot of
real-time multimedia applications (e.g. videoconferencing) are variable bit rate (VBR) flows.
• 802.11n is an ongoing next-generation high-throughput WLAN standard that intends to support about 400-600Mbps physical (PHY) layer data rates with more than 100Mbps effective throughput measured at the MAC layer. However, recent research work demonstrated that the throughput of
802.11 networks is bounded by the overhead of the MAC and PHY layer protocols and implementation.
A new scheme has been designed and proposed called aggregation with fragment retransmission
(AFR) to the 802.11n standard group, which supports transmissions of very large frames and partial
retransmissions in the case of channel errors.
• 802.11p is to support wireless connectivity amongst vehicles. The scope of this research is to design
and implement a cross- layer mechanism (routing-MAC-PHY) to optimise the performance of
802.11p-based vehicular networks with QoS support.
Innovations and advantages of the offer:
- Novel and effective resource allocation and management schemes for wireless LAN systems.
- A new scheme called aggregation with fragment retransmission (AFR) to the 802.11n standard
group, which supports transmissions of very large frames and partial retransmissions in the case of channel errors.
Experimental results show that the new scheme significantly improves the performance of standard
EDCA in terms of throughput, delay, loss and fairness metrics.
A performance study indicates that AHCCA could support bandwidth and delay requirements for both
CBR and VBR flows under a large range of network loads.
What are we looking for:
- Type of partner sought: Industry
- Specific area of activity of the partner: Telecommunications & IT (e.g. equipment providers, network
- Task to be performed by the partner sought: Support further development and implementation in
wireless testbeds and experiments.
- joint further development