Accession Number : ADA184414

Title :   A Window Random Access Algorithm for Environments With Capture.

Descriptive Note : Technical rept.,

Corporate Author : VIRGINIA UNIV CHARLOTTESVILLE DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Lyons,Daniel F ; Papantoni-Kazakos,P

PDF Url : ADA184414

Report Date : 03 Sep 1987

Pagination or Media Count : 28

Abstract : In packet radio environments, where users are independent and bursty, the deployment of Random Access transmission Algorithms, (RAAs), is recommendable. Those algorithms are implemented by each user independently, they are insensitive to changing user population, and they induce low delays. Several such algorithms have been proposed, and generally analyzed in idealistic, (noiseless and with no propagation delays), environments, and subject to the assumptions that when simultaneous transmission is then necessary, and that a single transmission is involved packets is lost and retransmission is then necessary, and that a single transmission is always received correctly. In realistic packet radio environments, however, several phenomena occur. Specifically, atmospheric noise, forward propagation delays, and multipath fading are present. Due to the atmospheric noise and the multipath fading, single transmissions are not always received correctly by the receiver. In addition, the differential forward propagation delays may be used beneficially, to allow locking in and thus capture of some packet, when simultaneous transmissions occur.

Descriptors :   *RADIO EQUIPMENT, *PACKETS, *WINDOWS, *RADIO RECEPTION, MULTIPATH TRANSMISSION, FEEDBACK, DELAY, CHANNELS, ALGORITHMS, ACCESS

Subject Categories : Command, Control and Communications Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE