Computing Dilution of Precision (DOP) for GPS

Computing Dilution of Precision (DOP) For 4 or More Satellites

For each satellite n define:

  • a n,1 = sin az cos el
  • a n,2 = cos az cos el
  • a n,3 = sin el

Where:

el = Local elevation angle, and az = Local azimuth angle (from North)

Next, form the line-of-sight matrix A for all satellites used in the solution:

line of sight matrix A and its transpose

covariance matrix and DOPs from the covariance matrix