On Optimizing the Backoff Interval for Random Access Schemes
- UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
- Jing Deng, Assistant Professor (Creator)
- Institution
- The University of North Carolina at Greensboro (UNCG )
- Web Site: http://library.uncg.edu/
Abstract: To improve the channel throughput and the fairness
of random access channels, we propose a new backoff algorithm,
namely, the sensing backoff algorithm (SBA). A novel feature of
the SBA scheme is the sensing mechanism, in which every node
modifies its backoff interval according to the results of the sensed
channel activities. In particular, every active node sensing the successful
transmission decreases its backoff interval by an additive
factor of the transmission time of a packet. In order to find the
optimum parameters for the SBA scheme, we have studied the optimum
backoff intervals as a function of different number of active
nodes (N) in a single transmission area with pure ALOHA-type
channels.We have found that the optimum backoff interval should
be 4N times the transmission time of a packet when the random
access channel operates under a pure ALOHA scheme. Based on
this result, we have numerically calculated the optimum values of
the parameters for SBA, which are independent of N. The SBA
scheme operates close to the optimum backoff interval. Furthermore,
its operation does not depend on the knowledge of N. The
optimum backoff interval and the SBA scheme are also studied by
simulative means. It is shown that the SBA scheme out-performs
other backoff schemes, such as binary exponential backoff (BEB)
and multiplicative increase linear decrease (MILD). As a point of
reference, the SBA scheme offers a channel capacity of 0.19 when N
is 10, while the MILD scheme can only offer 0.125. The performance
gain is about 50%.
On Optimizing the Backoff Interval for Random Access Schemes
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Created on 2/22/2011
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Additional Information
- Publication
- IEEE Transactions on Communications, vol. 51, no. 12, pp. 2081-2090, December 2003.
- Language: English
- Date: 2003
- Keywords
- Backoff algorithm, Backoff interval, Binary exponential backoff (BEB), Multiplicative increase linear decrease (MILD), Random access, Sensing backoff algorithm (SBA)