Session (measurement)
In geodesy , a session is the subdivision into overlapping areas in which coordinated, simultaneous measurements are carried out in the case of spatially extensive measurement campaigns .
Such subdivisions can gradually cover a large area, even if the number of measuring instruments or measuring teams is not sufficient for the entire project area. A computational unification of the entire network can be achieved retrospectively through planned overlaps , for example in the form of a network adjustment . The sub-areas can overlap either on their border strips by observing their measuring points in two or three sessions (time periods), or by means of centrally located, repeatedly measured reference points .
The term " session " is based on that of the session of a corporation. As a scientific and technical form of organization, it is mainly used in geodesy - especially satellite geodesy - and in radio astronomy .
A spatial or temporal subdivision of a measurement campaign may also be necessary if the computing capacity of the computer system is insufficient to evaluate the system “in one go” or if the number of parameters to be determined by the measurements is too large. Even if the connection of individual system parts is not sufficiently stable, a so-called session solution with subsequent unification through attachment can be more favorable than a poorly conditioned overall solution.