Analysis and application of non-linear methods for increasing interference immunity of radio communication systems operating on board a spacecraft with electric propulsion thrusters

Abstract

Experience in the use of electric propulsion thrusters (EPT) on board a spacecraft revealed their advantages in comparison with the chemical-fuel engines, but along with this it revealed a number of peculiarities related to the electrodynamic effect on the onboard systems. The EPT self-emission influence on the interference immunity of onboard communication systems is discussed in the paper as one of the side effects, as well as the methods for contradicting results of such influence .Stationary plasma thrusters (SPT), emission characteristics of which are well known, are used for discussion as an example. The influence of SPT emission in the radio-frequency range on the interference-immunity characteristics of a typical radio receiving system is analyzed in the first part of the paper. The method of simulation modeling with the representation of mathematical models in the MATLAB/Simulink environment was chosen as an apparatus for the analysis. Application of non-linear methods for signal processing with the aim to increase interference immunity of communication systems of SC with EPT is considered in the second part of the paper. The compensation method of protection against SPT interference is discussed that is based on the adaptive extraction of characteristic components of the emission process within the temporal domain, their cutting out, and two-stage interpolation of the received signal complex envelope. It is shown that as a result of the developed algorithm use the power gain can be as high as 3 dB with the signal-to-extracted component ratio (SECR) of 10 dB, 7 dB with SECR of 5 dB, and over 12 dB with SECR of 0 dB, if compared to the case, when the means for suppressing interference from SPT.