Design and evaluation of symmetric space-time adaptive processing of an array antenna for precise global navigation satellite system receivers

Abstract

The most effective method for overcoming the interference vulnerability of global navigation satellite system (GNSS) receivers is to use an adaptive array antenna which has the capability of nulling or beamforming to a certain direction. The space-time adaptive processing (STAP) algorithm, which is very effective in signal processing of the array antenna for anti-interference, is studied. The phenomenon of pseudorange error in STAP is analysed with a new superposition method of linear line correlation functions. From this analysis, a new symmetric STAP algorithm, which uses an appropriate constraint condition for GNSS signals, is proposed to completely prevent this pseudorange error. The new STAP algorithm performance is verified and confirmed by simulations and experiments with a four-element array antenna. According to the simulation results, the new STAP algorithm has no pseudorange error, whereas the already existing STAP algorithm has an error of 1.6m. Also experiments with four RF channels analogue-to-digital converter data and a real-time receiver confirm the effectiveness of their precise STAP algorithm which is easy to implement.