A Conflict Resolution Algorithm for Noisy Multiaccess Channels
Abstract
An efficient contention resolution scheme has been developed by Gallager to be used in allocating usage of common channel to a large number of independent transmitters. Time is divided into equal size intervals called slots. Message transmissions begin only at slot boundaries and do not overlap boundaries. Depending on the channel history, as monitored by the users, the algorithm defines a system-wide 'transmission interval' at the beginning of each slot. A user can only transmit when it possesses a meassage with a generation time falling at the current transmission interval. This algorithm is modelled as a Markov process. The Gallager algorithm is based on the assumption that the transmitters make no errors in the detection of channel activity. This thesis investigates the case where a limited class of detection errors is introduced into the system. A modified algorithm is proposed to effectively correct these errors. This Noisy Channel Algorithm includes a stack mechanism and two special processing states. The algorithm is again modelled as a Markov process and retains some key features of the Gallager algorithm. The algorithm is analyzed and the degree to which system performance is downgraded by errors is determined.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1980
- Accession Number
- ADA086767
Entities
People
- David M. Ryter
Organizations
- Massachusetts Institute of Technology