Method for Rapid Judgment of Faulty Stations of Multilateration System

An airport surface multilateration system based on the time difference of arrival (TDOA) positioning principle establishes equations to calculate the position of target through utilizing the TDOA of targets’ answering signals to the ground receiving stations. The fault with any ground receiving station will result in a significant measuring error of signal’s arrival time and have a lethal impact on the accuracy of positioning. A method for rapid judgment of station fault based on the smoothing filtering and judgment of deviation statistics is proposed. The target location will be firstly estimated through smoothing filtering of data, thus it is allowed to calculate the deviation of measuring position and the estimated position. When the deviation exceeds a certain threshold, it indicates that there is a large increase in the errors of single stations; then, the TDOA of each station can be calculated based on the estimated position, and the deviation can be calculated through comparison with the actually measured value of TDOA. For the stations with large deviation of TDOA as indicated by statistics, the station with the most deviations of large TDOA will be the station with problems. A simulation experiment for an airport indicates that the method can rapidly and effectively judge the faulty station.