Efficiency analysis for signal combining of antenna arraying in deep space TT&C systems

Antenna arraying is an efficient method to increase antenna equivalent gain in deep space telemetry tracking and command (TT&C) applications where the signal to noise ratio (SNR) is so low that the received signals from the space craft can not be efficiently processed at the receiver. Combining efficiency is the key factor to determine which combining method can be employed for antenna arraying in deep space communications. However, no related researches have been carried out in the literatures. In this paper, detailed theoretic analysis is carried out for the combining efficiency for full-spectrum combining (FSC) methods, which can provide reference for TT&C receiver designers. Analysis results show that the SUMPLE correlation algorithm is optimal in combining efficiency, higher combining efficiency can be gained with higher SNR at each antenna, more antennas, narrower correlation bandwidth and narrower phase difference loop bandwidth.