Abstract:

Due to the inhomogeneity of the atmosphere, radio waves are subjected to refraction during the propagation process, which reduces its propagation speed and bends the propagation path. If this refraction effect is not taken into account when the source is localized through conventional multi-station time difference of arrival (TDOA)-based methods, a large localization error will occur. In this paper, the influence of atmospheric refraction on the TDOA localization error under the known elevation constraint is analyzed. It is proved that the iterative correction method cannot achieve the optimum under this elevation constraint (the constraint conditions are redundancy conditions). Consequently, a new atmospheric refraction correction method is proposed where iterative methods are applied to obtain initial solutions, which are further refined by improved particle swarm optimization (PSO) methods. The effectiveness of the proposed method is validated through simulation results and analyses.

Key words: elevation constraint, atmospheric refraction, error, iteration, particle swarm optimization (PSO)