Deere + Company

Navcom Technology, Inc.

Yujie Zhang

Liwen L Dai

Yiqun Chen

Sonia U Kuntz

Min Wang

Ronald R Hatch

Michael Alan Zeitzew

Sonia Kuntz

A satellite corrections generation system receives reference receiver measurement information from a plurality of reference receivers at established locations. In accordance with the received reference receiver measurement information, and established locations of the reference receivers, the system determines narrow-lane navigation solutions for the plurality of reference receivers. The system also determines clusters of single-difference (SD) narrow-lane floating ambiguities, each cluster comprising pairs of SD narrow-lane floating ambiguities for respective pairs of satellites. A satellite narrow-lane bias value for each satellite of a plurality of satellites is initially determined in accordance with fractional portions of the SD narrow-lane floating ambiguities in the clusters, and then periodically updated by a Kalman filter. A set of navigation satellite corrections for each satellite, including the satellite narrow-lane bias value for each satellite, is generated and transmitted to navigation receivers for use in determining locations of the navigation receivers.

Navigation satellite orbit and low latency clock determination with wide-lane and narrow-lane bias corrections

A satellite corrections generation system receives reference receiver measurement information from a plurality of reference receivers at established locations. In accordance with the received reference receiver measurement information, and established locations of the reference receivers, the system determines wide-lane navigation solutions for the plurality of reference receivers. The system also determines clusters of single-difference (SD) wide-lane floating ambiguities. A satellite wide-lane bias value for each satellite of a plurality of satellites is initially determined in accordance with fractional portions of the SD wide-lane floating ambiguities in the clusters and over-range adjustment criteria. A set of navigation satellite corrections for each satellite, including the satellite wide-lane bias value for each satellite, is generated and transmitted to navigation receivers for use in determining locations of the navigation receivers.

Navigation satellite wide-lane bias determination and over-range adjustment system and method

Example methods disclosed herein include accessing carrier phase measurements and code measurements obtained for a plurality of satellite signals of a global navigation satellite system. Disclosed example methods also include determining an initial set of floating-point ambiguities based on the measurements, the initial set of floating-point ambiguities including inter-frequency bias (IFB). Disclosed example methods further include performing a least squares search process based on the initial set of floating-point ambiguities to determine a set of integer ambiguities and an estimate of the IFB. In some examples, an additional (e.g., wide-lane) filter is used to realize a combination of carrier phase and code IFB. In some examples, IFB estimation is further realized by determining a median of IFB estimates over a window time. In some examples, the resulting IFB estimate and the set of integer ambiguities are used to estimate a position of a receiver, determine a satellite correction signal, etc.

Estimation of inter-frequency bias for ambiguity resolution in global navigation satellite system receivers

A satellite corrections generation system receives reference receiver measurement information from a plurality of reference receivers at established locations. In accordance with the received reference receiver measurement information, and established locations of the reference receivers, the system determines narrow-lane navigation solutions for the plurality of reference receivers. The system also determines, in accordance with the narrow-lane navigation solutions, at a first update rate, an orbit correction for each satellite of a plurality of satellites; at a second update rate, a clock correction for each such satellite; and at a third update rate that is faster than the second update rate, an update to the clock correction for each such satellite. Further, the system generates navigation satellite corrections for each such satellite, including the orbit correction updated at the first update rate, and the clock correction that is updated at the third update rate.

Navigation satellite orbit and clock determination with low latency clock corrections

A satellite corrections generation system receives reference receiver measurement information from a plurality of reference receivers at established locations. In accordance with the received reference receiver measurement information, and established locations of the reference receivers, the system determines wide-lane navigation solutions for the plurality of reference receivers. The system also determines clusters of single-difference (SD) wide-lane ambiguity values, each cluster comprising pairs of SD wide-lane floating ambiguities for respective pairs of satellites. A satellite wide-lane bias value for each satellite of a plurality of satellites is initially determined in accordance with fractional portions of the SD wide-lane floating ambiguities in the clusters, and then periodically updated by applying SD wide-lane integer constraints in a Kalman filter. A set of navigation satellite corrections for each satellite, including the satellite wide-lane bias value for each satellite, is generated and transmitted to navigation receivers for use in determining locations of the navigation receivers.

Navigation satellite wide-lane bias determination system and method

A wide-lane ambiguity and a respective satellite wide-lane bias are determined for the collected phase measurements for each satellite for assistance in narrow-lane ambiguity resolution. Satellite correction data is determined for each satellite in an orbit solution based on the collected raw phase and code measurements and determined orbital narrow-lane ambiguity and respective orbital satellite narrow-lane bias. A slow satellite clock correction is determined based on the satellite orbital correction data, the collected raw phase and code measurements, and clock narrow-lane ambiguity and respective satellite narrow-lane bias. A low latency clock module or data processor determines lower-latency satellite clock correction data or delta clock adjustment to the slow satellite clock based on freshly or recently updated measurements of the collected raw phase measurements that are more current than a plurality of previous measurements of the collected raw phase measurements used for the slow satellite clock correction to provide lower-latency clock correction data.

Precise low-latency GNSS satellite clock estimation

A system and method for providing improved correction information to navigation receivers includes receiving, from a plurality of reference stations at known locations, a plurality of satellite navigation measurements of signals from a plurality of global navigation satellites. A state of the plurality of global navigation satellites is computed based on the received satellite navigation measurements. Baselines, each corresponding to a pair of the reference stations, are identified. For each identified baseline, computing floating and integer values for a double-differenced integer ambiguity. Double-differenced integer ambiguities that satisfy a set of predefined conditions are identified, and the computed state of the plurality of global navigation satellites is adjusted in accordance with an integer value constraint applied to each double-differenced integer ambiguity that satisfies the set of predefined conditions. The correction information is computed from the adjusted computed state of the plurality of global navigation satellites.

Navigation system and method for resolving integer ambiguities using double difference ambiguity constraints

A satellite clock error is determined for each navigation satellite based on the pseudo-range code measurements, the carrier phase measurements, and broadcast satellite clock errors provided by a receiver network. Differences are determined between the computed satellite clock errors and the broadcast clock errors for each satellite. For each constellation, a clock reference satellite is selected from among the navigation satellites, where the clock reference satellite has the median value of clock error difference for that satellite constellation. A correction is determined for the broadcast clock error by applying a function of the reference satellite's clock error to the broadcast clock error for each satellite in the one or more constellations.

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Torrance, CA, United States of America

Yujie Zhang