Research On Statistical Priority Based Multiple Access

With the rapid development of the information age,modern warfare has become a war of information,and in modern military warfare,the interaction of combat information needs to be faster and more accurate.At the same time,the generation of the data link accelerates the information interaction on the battlefield,and greatly improves the command capability of the command platform and the cooperative combat capability of the combat platform.It can be said that the tactical data link plays a decisive role in a war.Choosing the appropriate MAC protocol and allocating limited wireless bandwidth resources more reasonably are the key to the evaluation of tactical data links.As a new generation of tactical data link system of the US military,TTNT adopts the MAC protocol based on the statistical priority multiple access protocol SPMA.Compared with the traditional MAC protocol,the SPMA protocol can not only provide a variety of multi-purpose services,but also provide lower transmission delay and higher transmission success rate for high priority packets.Firstly,by analyzing and comparing the performance characteristics of several common MAC protocols,and according to the technical characteristics of TTNT data link,and aiming at the shortcomings of existing MAC protocols in tactical data link,this thesis introduces the MAC protocol of TTNT data link: SPMA protocol.Besides,this thesis elaborates on some mechanism in SPMA,including the channel detection mechanism in SPMA protocol,priority transmission decision mechanism,data packet coding mechanism,flow control mechanism,and data packet transmission flow chart.Then,the priority queue in the SPMA protocol was analogized to the M/G/1priority queue,and the slot transmission probability STP of the SPMA system at the saturation input was obtained by the fixed point analysis method.Moreover,based on STP,this thesis quantified the successful transmission rate,throughput and packet transmission delay of the data packet in the system.Finally,the SPMA software simulation platform was built.After giving the detailed design of the three modules of the simulation software(including channel module,physical layer module and link layer module),the slot transmission probability,throughput,packet transmission success rate and transmission delay of the system aresimulated.Then,the actual simulation results are obtained.,and through the analysis of the results,the correctness of the theoretical analysis is verified.