Phase smoothing in a virtually synchronized pseudolite system using stochastic clock modelling

A derivation of phase smoothing for a pseudolite system is given. The distinction to phase smoothing known from literature arises from the setup of the system. As of the employed free-running pseudolites, the main challenge is to properly estimate the pseudolite clocks. The better the pseudolite clocks are estimated, the more precise are the phase measurements and the more effective is phase smoothing. Two different methods for clock estimation are examined in terms of their applicability to phase smoothing. Simulated as well as real data are used in order to evaluate the precision gain by phase smoothing. Optimal solutions according to system restrictions are presented.