A Field Calibration Solution to Achieve High-Grade-Level Performance for Low-Cost Dual-Frequency GNSS Receiver and...

Area of Science:

• Geodesy and Geomatics
• Satellite Navigation Systems
• Atmospheric Science

Background:

• Low-cost dual-frequency Global Navigation Satellite System (GNSS) receivers and antennas enable new applications but suffer from poorly defined antenna phase patterns.
• This limitation increases noise in tropospheric zenith delay and coordinate time series, potentially causing systematic errors.

Purpose of the Study:

• To present a field calibration method for low-cost GNSS antennas using affordable equipment and cloud processing.
• To assess antenna quality and performance in the field, going beyond relative calibration.

Main Methods:

• A cloud-based web service for antenna calibration, including phase center variation (PCV) and phase center offset (PCO) computation.
• Utilizes low-cost equipment (~500 Euros) and requires limited specialist expertise.
• Field calibration applicable to various antenna types and ground planes with low-cost dual-frequency receivers.

Main Results:

• Carrier phase residuals reduced by 11-34% on L1 and 19-39% on L2 for low-cost antennas.
• For the cheapest antenna, L1 residual decreased from 3.85 mm to 3.41 mm, and L2 from 5.34 mm to 4.3 mm.
• Median Absolute Deviations (MADs) in the vertical direction for Post Processed Kinematic (PPK) reduced by 20-24%, comparable to geodetic-grade antennas.
• Improved Precise Point Positioning (PPP) results with reduced height biases.

Conclusions:

• The developed field calibration method effectively enhances the performance of low-cost GNSS antennas.
• This approach democratizes high-accuracy GNSS applications by reducing equipment costs and complexity.
• The method provides a valuable tool for deformation monitoring, GNSS meteorology, and precise positioning.