Performance of CSMA and TDMA protocols for break-in channel access in a frequency hopping (FH) narrowband high frequency (HF) blocked channel environment

Abstract

Military systems often require multiple communication mode capabilities, such as teletype, facsimile, digital data, and digital voice, as well as some network layer functions such as break-in and late network entry. Channel assignment for these network layer functions, called service functions, is strictly an overhead from a communication point of view. In a narrowband (3 kHz) high frequency (HF) channel employing a frequency hopping (FH) waveform, selecting an appropriate protocol for a given set of operational parameters, such as message length and channel traffic load, is critical in resulting throughput efficiency and service channel access time. This paper investigates two candidate protocols, carrier sense multiple access (CSMA) and conventional time-division multiple access (TDMA) protocols for service channel access and break-in. It contains detailed descriptions and calculated performance measures of these protocols obtained from simulation and analyses. Specifically, throughput, transmission success rate, and service channel access time were calculated as a function of channel traffic load. Suggestions are made regarding protocol selection. >