Patent ID: 8638257
Filing Date: 2014-01-28
Classification: G01S

Abstract:
1. A GNSS receiver comprising: an antenna structure consisting of two or more antennas with each antenna spaced apart from neighboring antennas by less than one wavelength of a carrier signal in GNSS satellite signals; a phase map that contains carrier phase difference error values associated with angles of incidence of the GNSS satellite signals at the antenna structure and line biases associated with operation of the GNSS receiver and calculated for respective pairs of antennas based on phase difference values; one or more processors configured to process the GNSS satellite signals received by the antennas and calculate estimated orientation of the antenna structure directly from differences in carrier phase angle measurements of incoming GNSS carrier signals at the antennas, determine the angles of incidence of the respective GNSS satellite signals based on positions of respective satellites and the estimated orientation of the antenna structure, enter the phase map using the angles of incidence and retrieve associated carrier phase difference error values, and utilize the associated carrier phase difference error values to correct the estimated orientation to produce an updated orientation; and the one or more processors further configured to re-enter the phase map to calculate a new updated orientation, utilizing updated angles of incidence, until a change in the new updated orientation is less than an error gradient associated with the phase map.