Network design strategies applicable to GPS surveys using three or four receivers

Strategies applicable to the design ofGPS surveys involving deployment of either three or four compatible receivers are presented. During aGPS observing session, the receivers operate simultaneously, producing three-dimensional cartesian coordinate differences for the lines interconnecting the receivers. Different strategies provide the network designer with several options for planning the survey. The designer may opt for a survey in which each mark is occupied three times, that is, during three separate observing sessions, or he may elect a more economical survey in which each mark is occupied only twice. The designer may also choose between two fundamentally different network geometries (a loop geometry or an areal geometry) to design a survey compatible with the spatial distribution of network marks. The strategies can be extended to other geometries. The strategies produce efficient networks in that no two marks are jointly occupied for more than one observing session. This feature produces the maximum number of distinct, directly observed lines for the given number of receivers and observing sessions. The strategies also favor observations over those lines connecting marks near one another. This feature helps survey logistics by reducing travel time between observing sessions.