Research On AOS Space Channel Multiplexing

With the development of space technology, in order to meet the needs of thecomplex spacecraft, CCSDS developed the advanced rail system (AOS) based onconventional on-orbit system (COS) in1986to meet the complexity and high speedrequirements of transfering information and promote the common development of spacescience. At present, the AOS are becoming more and more outstanding in the field ofspace technology.Space channel multiplexing technology is a hot point of the research of AOSagreement. This paper studies the AOS two stage multiplexing technology, mainlyincluding the following contents.First of all, this paper studies the multiplexing of classic algorithm. The paperintroduces performance parameters of evaluating the virtual channel schedulingalgorithm and makes analysis of the classical scheduling algorithm performancecharacteristics and the applicable scope; Then it introduces source package model ofpacket channel process, and the polling scheduling algorithm of classical schedulingalgorithm is studied, converting it to vacation queue system of the dragon’s not emptylimited service in queuing theory to carry on the analysis, and finally the system averagedelay of the lower limit is derived, and it is verified through simulation and providesguidance for engineering design.Secondly, this paper studies the frame generation algorithm and dynamicscheduling algorithm joint. The simplified theoretical calculation formula of the meanof the average generation time and average packet delay of the high efficient generationalgorithm frame is concluded, and the correctness is verified through the simulation.Theadaptive frame generation algorithm is further researched, through the strict theoreticalanalysis, The precise calculation formula of effective information transmission rate ofthe adaptive algorithm is concluded, and the correctness is verified through thesimulation. On this basis, comparing the high efficiency algorithm to the adaptive framealgorithm, the simulation results show that the latter have smaller frame rise time mean,variance and the average packet delay of the mean value, variance, and effective information transmission rate of adaptive algorithm is slightly lower than efficientalgorithm; At last, it puts forward a kind of scheme which combined the adaptivealgorithm with dynamic scheduling algorithm and compares to the scheme combiningthe traditional high efficiency algorithm with dynamic scheduling algorithm, thesimulation results show that the scheme combining the adaptive algorithm with thevirtual channel scheduling algorithm has the lower packet delay and higher channelutilization.