M.S.

This thesis analyzes the simulation of a Single Channel Ground and Airborne Radio System (SINCGARS), currently in use by the United States Army. Although this radio was mainly designed as a voice radio, it also has the capability to transmit data messages. The amount of voice traffic which is capable of flowing through the channel, without causing detrimental effects to users, is studied. The struggle to transmit data versus voice is considered. Various other factors capable of influencing performance are explored. These consist of net access delay, net size, frequency of information transmission, and most importantly, data message transmission delays. The radio net is modeled in EXTEND, a commercial software package. The program simulates preselected and quantified data as well as coded voice data. The data is then processed through the single radio channel. Message transmission delays are calculated by EXTEND and examined for individual users. The primary contribution of this thesis is the development of an analytical approximation to estimate message transmission delays. The analysis is based on simulated data from EXTEND. A general expression is derived for each member, or user, on the SINCGARS net. This is an effort not only to simplify and generalize the method of estimating delay, but it also serves to shorten the amount of time spent on analysis, by reducing the dependence upon simulation. Applications of this research include the analysis of SINCGARS, under the Inter-Vehicular Information System (IVIS) protocol, using simulation and statistical approximations. If the performance of a new system can be accurately evaluated using a general expression, thus eliminating the need for repeated simulations, performance and system analysis time can be significantly reduced. / M.S.