Research On Key Technology Of The Integrated TT&C And High Speed Data Transmission System

With the development of space technology,the number and types of satellites have increased rapidly,the space missions become more and more complicated,and the independent TT&C(telemetry,track and command)and data transmission system have been unable to meet the satellite demands for measurement,control and data transmission services.It is an effective solution that using the integrated TT&C and data transmission system to improve the performance of measurement and control services and data transmission.It is the key technology in the integrated system that the combination of ranging and data transmission.At present,the data transmission rate is usually settled around 3Mbps when conducting the research on the integrated system,while the research of high data transmission rate has not been studied.Therefore,this paper focuses on the combination of ranging and high rate data transmission which is the key technology of the integrated TT&C and high rate data transmission system,studies the way to complete the ranging under the condition of high speed data transmission,and designs the signal form and processing method.Based on the analysis above,the research of this paper is conducted as follows:Firstly,the basic model of distance measurement based on phase delay measurement and the basic model of data transmission are studied,and the ranging signals and data transmission signals are analyzed.With the studies of the models and signals,the main methods of combining ranging and data transmission are analyzed.According to the conditions of high speed data transmission,the main objects of this paper are determined as: the ranging pseudo code and transmission data combination method based on GMSK(Gaussian Minimum frequency Shift Keying)modulation,and the ranging and data transmission combination method based on data transmission signal completing ranging.Secondly,for the above two methods,the principles of combining ranging and data transmission and the factors that affect the ranging performance and data transmission performance are analyzed separately.Ranging accuracy and bit error rate are determined as the parameters to evaluate the ranging performance and the data transmission performance,while in the ranging model based on the phase delay measurement,the ranging accuracy corresponds to the phase measurement error of the ranging signal.By analyzing the influence of the factors on the phase measurement error of ranging signal and the bit error rate,the ranging performance and data transmission performance of the two methods can be obtained.Finally,comparing the performance of the two methods,and it can be concluded that the combination method based on data transmission signal completing ranging can reach lower bit error rate and processing algorithms complexity,and the ranging error is about one order of magnitude higher.While for high speed data transmission,this combination method can also achieve high accuracy ranging.On the basis of the analysis result,the combination method based on data transmission signal completing ranging is selected for the integrated TT&C and high speed data transmission system.And then,the combination signal form and processing method are designed for ranging and high speed data transmission which is higher than 100 Mbps.