Dilution of precision (DOP)
The factor by which the accuracy of a GNSS, or other radio-navigation system position and time co-ordinates are degraded by geometrical considerations of the constellation of GNSS satellites used by the receiver.
– Geometric dilution of precision (GDOP). The factor for the combined 3D-position and time accuracy.
– Position dilution of precision (PDOP). The factor for the 3D-position accuracy.
– Horizontal dilution of precision (HDOP). The factor for the horizontal position accuracy.
– Vertical dilution of precision (VDOP). The factor for the vertical accuracy.
– Time dilution of precision (TDOP). The factor for the time accuracy.
Source: Nick Ward, Vicechair, IALA e-Nav Committee, March 2009
