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A Modified Point Coordination Function (Modified PCF) in IEEE 802.11 Wireless LAN

Kanjanavapastit, A. and Landfeldt, Björn LU (2003) 11th IEEE International Conference on Networks, ICON 2003 In [Host publication title missing] p.561-566
Abstract
With recent advances in wireless technologies, wireless LANs are becoming increasingly widespread as an alternative to fixed access technologies. The IEEE 802.11 standard has gained the most popularity among the different standards and is currently being deployed both within enterprises as well as being used for public access.

One of the weaknesses of the basic medium access in the 802.11 standard is its relatively poor support for real-time trafflc. In order to provide this support, the MAC layer implements a Point Coordination Function (PCF). However, since the PCF is based on a centralized polling protocol, some bandwidth is wasted due to the polling overheads and null packets in case the polled stations do not have any data to... (More)
With recent advances in wireless technologies, wireless LANs are becoming increasingly widespread as an alternative to fixed access technologies. The IEEE 802.11 standard has gained the most popularity among the different standards and is currently being deployed both within enterprises as well as being used for public access.

One of the weaknesses of the basic medium access in the 802.11 standard is its relatively poor support for real-time trafflc. In order to provide this support, the MAC layer implements a Point Coordination Function (PCF). However, since the PCF is based on a centralized polling protocol, some bandwidth is wasted due to the polling overheads and null packets in case the polled stations do not have any data to traosmit. In order to reduce the waste and increase the channel utilization this paper presents a modified version of the standard PCF.

The modified PCF uses a distributed polling protocol @PP) as an access mechanism for the uplink transmission. The transmission period in the modified PCF consists of a distributed polling protocol period @PPP) which is controlled by the DPP and the real-time traffic downlink period (RTDP). The paper further introduces a technique for dealing with the hidden station problem for use together with the proposed modification. This problem occurs when one or more stations misinterpret the status of the medium leading to unforeseen collisions.

Using simulation we compare the performance of the modified PCF with the standard PCF when they are used to support voice transmissions. The results show that the modified PCF significantly improves the channel utilization since it can support a higher number of stations than the standard PCF. (Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Chapter in Book/Report/Conference proceeding
publication status
published
subject
in
[Host publication title missing]
pages
561 - 566
conference name
11th IEEE International Conference on Networks, ICON 2003
external identifiers
  • Scopus:78649961545
ISBN
0-7803-7788-5
DOI
10.1109/ICON.2003.1266250
language
English
LU publication?
no
id
5fbcd8e1-c522-40ee-a9e9-8f34ef0c0fd2 (old id 3216696)
date added to LUP
2012-11-27 15:37:42
date last changed
2016-10-13 05:02:15
@misc{5fbcd8e1-c522-40ee-a9e9-8f34ef0c0fd2,
  abstract     = {With recent advances in wireless technologies, wireless LANs are becoming increasingly widespread as an alternative to fixed access technologies. The IEEE 802.11 standard has gained the most popularity among the different standards and is currently being deployed both within enterprises as well as being used for public access.<br/><br>
One of the weaknesses of the basic medium access in the 802.11 standard is its relatively poor support for real-time trafflc. In order to provide this support, the MAC layer implements a Point Coordination Function (PCF). However, since the PCF is based on a centralized polling protocol, some bandwidth is wasted due to the polling overheads and null packets in case the polled stations do not have any data to traosmit. In order to reduce the waste and increase the channel utilization this paper presents a modified version of the standard PCF.<br/><br>
The modified PCF uses a distributed polling protocol @PP) as an access mechanism for the uplink transmission. The transmission period in the modified PCF consists of a distributed polling protocol period @PPP) which is controlled by the DPP and the real-time traffic downlink period (RTDP). The paper further introduces a technique for dealing with the hidden station problem for use together with the proposed modification. This problem occurs when one or more stations misinterpret the status of the medium leading to unforeseen collisions.<br/><br>
Using simulation we compare the performance of the modified PCF with the standard PCF when they are used to support voice transmissions. The results show that the modified PCF significantly improves the channel utilization since it can support a higher number of stations than the standard PCF.},
  author       = {Kanjanavapastit, A. and Landfeldt, Björn},
  isbn         = {0-7803-7788-5},
  language     = {eng},
  pages        = {561--566},
  series       = {[Host publication title missing]},
  title        = {A Modified Point Coordination Function (Modified PCF) in IEEE 802.11 Wireless LAN},
  url          = {http://dx.doi.org/10.1109/ICON.2003.1266250},
  year         = {2003},
}