Abstract: The method of precise position determination, in particular for geodetic positioning by means of carrier-frequency phase-difference measurement on GPS satellites, uses a double difference (.DELTA..phi..sub.12.sup.nm (k)) of a measured phase values, forms an initial solution for a position vector (x.sub.jc) by means of a compensation calculation, and actual phase ambiguities (x.sub.jN) and then integer alternative phase ambiguities (x.sub.jA).A rapid reduction in the number of alternative phase ambiguities (x.sub.jA) to be processed and automatic statistical protection of the results is achieved by means of special statistical selection tests, using a corresponding cofactor matrix (Q.sub.xxj) and an a posteriori rms error (m.sub.0s) of the initial solution.In this way, the required number of satellites (4 to 5) observed and the observation duration (a few minutes) can be reduced considerably, likewise the computer cost. Operator decisions are eliminated.

Abstract: A terrestrial surveying system comprising an electro-optic total station (1) for combined measurement of angle and distance and a connection to data storage (11) or data processing devices (20), the total station (1) and at least one portable position-measuring unit, which is separated spatially from the total station and equipped with a receiver (3) for a satellite position-measuring system, are connected to one another through a wireless data transfer device (12, 13). The data processing device is preferably set up for determining coordinates, for coordinate transformation from the satellite position-measuring system to the terrestrial coordinate system of the total station and for consistency checking of the data determined.