. Dilution of precision (DOP) is the term used for expressing the mathematical quality of fix solution , and Position DOP is used in GPS navigation to define how accurate is the fix , High PDOP means Low accuracy of the position and Low PDOP means good position and in GPS navigation this depends on the position of the satellites in the sky and how good is the LOP’s intersect.
DOP can be of one direction like, time (TPOD) , horizontal DOP , vertical DOP geometric DOP , and position DO