A MLAT algorithm based on target pressure altitude

MLAT (Multilateration) techniques have been successfully deployed for airport surveillance for quite some time now, it makes use of signals transmitted by an aircraft to calculate the position of aircraft. However, Multilateration techniques when applied in a wide area surveillance environment for aircraft target positioning, for the impact of Geometric Dilution of Precision (GDOP), the three-dimensional positioning algorithm for target positioning may result in relatively low positioning accuracy, and even cause divergence. For partial response signals transmitted by the civil aviation airborne secondary transponder contain target pressure altitude, the MLAT algorithm based on target pressure altitude can correct the three-dimensional positioning algorithm, reduce the dimensions of positioning equations, ensure algorithm convergence and increase positioning accuracy. The test results based on the practical application system illustrates the MLAT algorithm based on target pressure altitude is more accurate than the traditional three-dimensional positioning algorithm alone.