Portable GNSS survey system

Abstract

Determining positions for a set of points using a GNSS rover unit includes receiving a correction signal from a GNSS base unit. The GNSS base unit is located at a fixed point. The correction signal is used to determine a position of a point of the set of points. The position is stored in memory of the GNSS rover unit as position data. These steps are repeated for each point in the set of points. Raw GNSS data of the GNSS base unit is transmitted to the server system. A corrected position of the GNSS base unit is received from the server system. The position data is translated based on the corrected position of the GNSS base unit to produce adjusted position data.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit to U.S. Provisional Patent Application No. 62 / 093,959, filed Dec. 18, 2014, the disclosure of which is hereby incorporated herein by reference in its entirety for all purposes.BACKGROUND[0002]1. Field[0003]The present disclosure relates generally to geodesy and precise positioning of a handheld geodesic device.[0004]2. Related Art[0005]Navigation receivers that use global navigation satellite systems, such as GPS or GLONASS (hereinafter collectively referred to as “GNSS”), enable a highly accurate determination of the position of the receiver. The satellite signals may include carrier harmonic signals that are modulated by pseudo-random binary codes and that, on the receiver side, may be used to measure the delay relative to a local reference clock. These delay measurements may be used to determine the pseudo-ranges between the receiver and the satellites. The pseudo-ranges are not true geometric ranges...

AI Technical Summary

Benefits of technology

The patent describes a system for using a GNSS rover unit to determine positions for a set of points. The system includes a GNSS base unit that sends a correction signal to the rover unit to correct the positions. This allows for more accurate positioning based on the correction information. The raw GNSS data from the base unit is transmitted to a server system, which then sends back the corrected position of the base unit. This adjusted position data is then translated based on the correction to produce the final position data.

Problems solved by technology

One well-known type of measurement error that can reduce the accuracy of differential navigation / positioning is multipath error.

Multipath errors are caused by the reflection of the GNSS satellite signals by surfaces located near the receiving antenna.

The combination of two (or more) signals at the antenna leads to the distortion of raw measurements.

Multipath errors may affect both pseudo-range and carrier phase measurements.

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