Modeling And Simulation Of Adaptive Rate Meteor Burst Communication System

The topic discussed in this paper is based on the research about the key techniques used in the Meteor Burst Communication system. The research is sponsored by the National Natural Science Fund, Huo Yingdong Institute Young Teachers Fund and the National Pre-research Task.Considering the meteor burst channel's characteristic of decreasing exponentially with time, in order to solve the problem of how to improve the utilization rate and the data throughput of the Meteor Burst Communication channel, this paper studies an adaptive rate transmission mechanism by estimating the real-time signal-noise ratio to change the bit rate.The simulation results show that the data throughput of this mechanism is 2-4 times as much as that of the fixed rate data transmissiom mechanism. Therefore, it is an effective and reliable communication method.Firstly, the paper introduces the basic concepts and the communication mechanism of the Meteor Burst Communication system, gives a general view of the development and the major applications of the Meteor Burst Communication technology, analyses the characteristics of the Meteor Burst Communication channel and discusses the primary parameters influencing the Meteor Burst Communication.Secondly, by analyzing the error controlling transmission modes of Mix I ARQ and Mix II ARQ, a Mix ARQ error controlling transmission mode is suggested on the basis of the coding rate adjusted by the decoding success rate of the receiving terminal. This transmission mode is then combined with the RS error correction code to be used in the Meteor Burst Communication.Thirdly, according to the characteristics of the variable rate methods, an adaptive rate transmission method based on the signal-noise ratio is put forward by analyzing the adaptive rate principles and methods. This method realizes the adaptive rate Meteor Burst Communication by implementing the dynamic change of the bit transmission rate on the basis of the signal-noise ratio and the coding rate change on the basis of the decoding success rate of the receiving terminal. Besides, this paper deals with way of confirming the variable rate threshold which is an important parameter affecting this method.Lastly, the paper introduces the simulation software SPW(Signal Processing Worksystem). The adaptive rate Meteor Burst Communication system is modularized. By adopting the software SPW, the meteor channel is simulated and the simulation model of the adaptive rate Meteor Burst Communication system is built on the basis of the signal-noise ratio. The threshold, the BER rate and the data throughput are simulated and analyzed. The simulation results indicate that the threshold confirmed in the way suggested in this paper is an ideal one. At the same time, the experiment shows that, under the same channel conditions, compared with the fixed rate data transmission mechanism, the adaptive rate transmission mechanism based on the signal-noise ratio ensures better anti-BER performance and higher data throughput.