Queueing and Interference among Messages in a Communication System with Transmission Delay

摘要

This thesis describes a technique for analyzing the statistical behavior of a two-way communication system with transmission delay (D). The transmit/receive devices, or servers, at the terminals are constructed so that they cannot transmit and receive simultaneously. Each server is therefore designed not to interrupt reception of a message with its own transmission. If D > O, each server is uncertain of the present state of the other, and may initiate transmission when the other has already begun to transmit, thus causing message interference. Interference is measured as the amount of one server's transmission which arrives at the other server when it is already transmitting. The relationship between the size of the delay and the amount of interference is studied here, as well as other quantities that describe the system behavior. The exact solution is available only for D = O, but an approximate solution is found for D very small with respect to the lengths of idle periods of the servers, and the asymptotic solution is obtainable for D very long. Good agreement is found between theoretical results and those obtained from simulation. Theoretical results have been obtained for a variety of systems fitting the two-way communication model proposed here, but there are certain important cases for which the only results yet available are from simulation. (Author)