A Procedure for Ambiguity Fixing with Dual-Frequency Phase and Code Observations.

Carrier phase measurements are accurate and commonly used to estimate precise baseline lengths. It is however necessary to fix ambiguities when using this technique in order to obtain good estimates of the baselines. In this paper, a new procedure for ambiguity fixing is proposed and the results show its effectiveness in estimating the ambiguity. The baseline is first estimated by pseudorange measurements. The subsequent ambiguity fixing requires a combination of carrier phase measurements with a wavelength that is at least twice the difference of the baseline error projections into the line of sights to satellites p and q for a direct estimation of the ambiguities. Real data observation was used to demonstrate the precise baseline estimation in comparison to the LAMBDA solution. The two solutions were found to be the same. [ABSTRACT FROM AUTHOR]