Multipath and ducting tolerant location techniques for automatic vehicle location systems

This paper discusses various methods of improving the accuracy of a linear least squares solution algorithm which is commonly used in Time Difference of Arrival (TDOA), hyperbolic location systems. Topics considered include methods of generating a useful weighting matrix and a residue examination scheme as the basis for rejecting data contaminated by large propagation delay errors. The performance of two linear schemes is compared to that of the nonlinear least squares solution using some 2000 sets of actual TDOA measurements.