GNSS signal processing with delta phase for incorrect starting position

• US 9,562,975 B2
• Filed: 03/19/2012
• Issued: 02/07/2017
• Est. Priority Date: 01/14/2008
• Status: Active Grant

• Current Assignee: Trimble Inc.
• Original Assignee: Trimble Inc.
• Inventors: Vollath, Ulrich, Talbot, Nicholas Charles, Glocker, Markus, Chen, Xiaoming, Leandro, Rodrigo
• Primary Examiner(s): McGue, Frank J
• Application Number:
  US14/002,721
• Publication Number:
  US 20130335266A1
• Time in Patent Office: 1,786 Days
• Field of Search: 342/357.02
• US Class Current: 1/1
• CPC Class Codes: G01S 19/07 providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
• CPC Class Codes: G01S 19/072 Ionosphere corrections
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/41 Differential correction, e.g. DGPS [differential GPS]
• CPC Class Codes: G01S 19/42 Determining position
• CPC Class Codes: G01S 19/43 using carrier phase measurements, e.g. kinematic positioning; using long or short baseline interferometry

Abstract

Methods and apparatus for processing of GNSS signals are presented. These include GNSS processing with predicted precise clocks, GNSS processing with mixed-quality data, GNSS processing with time-sequence maintenance, GNSS processing with reduction of position jumps in low-latency solutions, GNSS processing with position blending to bridge reference station changes, and GNSS processing with delta-phase correction for incorrect starting position.

Claims

1. A method of deriving a position of a rover using a receiver system, the method comprising:

a. obtaining an approximate anchor position for a first epoch, the approximate anchor position comprising at least one of an autonomous position determined by the rover or a differential position determined by the rover, the approximate anchor position determined without correction data for the first epoch from one or more reference stations,

b. using the approximate anchor position to determine a rover position difference for at least one succeeding epoch, the approximate anchor position being determined by the receiver system, thereafter

c. obtaining an improved anchor position for the first epoch, the improved anchor position comprising a synchronous position determined by the rover using correction data for the first epoch from one or more reference stations,

d. deriving an adjusted rover position difference for each said succeeding epoch, the adjusted rover position difference being determined by the receiver system, and

e. deriving the position of the rover for a current epoch from the improved anchor position for the first epoch and the adjusted rover position difference for the current epoch, the rover position being determined by the receiver system.

2. The method of claim 1,

wherein the approximate anchor position contains an initial error,

wherein the rover position difference for each said succeeding epoch contains a respective partial error based on the initial error, and

wherein operating the processor to derive an adjusted rover position difference for each said succeeding epoch comprises correcting each rover position difference for the respective partial error.

3. A tangible non-transitory computer-readable medium embodying instructions for enabling an apparatus to perform the method of claim 1.

4. A non-transitory computer readable medium encoded with a computer program that includes instructions to cause a processor to derive a position of a rover, comprising:

a. obtaining an approximate anchor position for a first epoch, the approximate anchor position comprising at least one of an autonomous position determined by the rover or a differential position determined by the rover, the approximate anchor position determined without correction data for the first epoch from one or more reference stations,

b. using the approximate anchor position to determine a rover position difference for at least one succeeding epoch,

c. obtaining an improved Fever anchor position for the first epoch, the improved anchor position comprising a synchronous position determined by the rover using correction data for the first epoch from one or more reference stations,

d. deriving an adjusted rover position difference for each said succeeding epoch, and

e. deriving the position of the rover for a current epoch from the improved anchor position for the first epoch and the adjusted rover position difference for the current epoch.

5. The apparatus of claim 4,

wherein the approximate anchor position contains an initial error,

wherein the rover position difference for each said succeeding epoch contains a respective partial error based on the initial error, and

wherein to derive an adjusted rover position difference for each said succeeding epoch comprises correcting each rover position difference for the respective partial error.