International Journal of Engineering and Applied Sciences (IJEAS)
ISSN: 2394-3661, Volume-4, Issue-4, April 2017
efficiency by reducing overheads. However, special
consideration must be taken to relate the frame sizes to the
physical data rate.
Fig. 3. Channel utilization in the absence of frame
B. The effect of A-MPDUs on Throughput
In this scenario, we investigate the impact of utilizing
A-MPDUs on system throughput. We use two physical data
rates: 100 Mbps and 150 Mbps. Number of stations is fixed to
12 stations. We vary the number of MPDU that are
aggregated into an A-MPDU. Each MPDU size is set to 2000
octets. Channel bandwidth is set to 40 MHz with 16-QAM
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Ashraf Bourawy received his MSC in Computer Engineering 2008
from Queen’s University, Kingston, Canada. He is working as a lecturer in
the department of computer science at Omar AL-Mukhtar University,
Albayda, Libya. His research interests focus primarily on topics in wireless
networks including: scheduling and QoS assurance in WLANs, ad hoc and
sensor networks, internet of things (IoT), network resource management and
Fig. 4. The effect of A-MPDU on Throughput
The system throughput increases with increase of the number
of MPDUs aggregated in an A-MPDU, as depicted in Fig.4.
This ensures that frame aggregation enhances the overall
system performance. This increase in throughput is mainly
cause by reducing the overhead imposed by MAC and PHY
headers, ACK frames, as well as inter-frame spacing.
However, when using large frame sizes, the gain in the
throughput is insignificant. This entails that larger frame sizes
requires higher physical rates.
Takwa Alokap is a fourth-year student in the department of computer
science at Omar AL-Mukhtar University, Albayda, Libya, expected to
graduate in spring session 2017. She is currently working on her capstone
project in the area of wireless networks. Takwa is interested in the field of
wireless local area networks. Her project focuses on analyzing the
performance of the IEEE 802.11ac amendment.
This paper evaluated the frame aggregation techniques
defined in the IEEE 802.11ac amendment. Simulation results
have shown that frame aggregation can effectively achieve
better channel utilization. Frame aggregation enhances MAC