Long baseline antenna arraying and its applications to telemetry in deep space explorations

The antenna arraying technique can be used to receive weak signals of deep space probes and improve the link budget. In the paper,a signal combining experiment of long baseline antenna arraying is carried out to receive the telemetry signal of relative low code rate.Combined with a telemetric software baseband receiver,the antenna arraying processing platform is conducted to deal with the signals and analyze the results.Meanwhile,three basic signal combining techniques called full spectrum combining,baseband combining and symbol stream combining are investigated in details.The field data collected by Chinese VLBI network for the Chang'E 2 satellite is processed and analyzed to evaluate the performances of three signal combining techniques.The results indicate that the efficiency calculated by the symbol signal-to-noise ratio exceeds 90% if ignoring the degradation of 1-bit quantification.The applicability of the long baseline antenna arraying is sufficiently confirmed.It provides an effective approach of deep space communications for the future missions.