Comparative Analysis of Single-antenna and Dual-antenna GNSS Configurations in Mobile Mapping Systems

Abstract

Mobile mapping systems (MMS) have become increasingly important in surveying and geospatial data acquisition, offering efficient and flexible solutions for collecting spatial information. While most commercial MMS platforms employ single-antenna configurations, dual-antenna setups have shown potential for improving positional accuracy and heading stability. This study investigates the comparative performance of single-antenna and dual-antenna configurations in post-processed kinematic (PPK) processing with tightly coupled integration. Data were collected using a custom-built MMS equipped with a Fiber Optic Gyroscope Inertial Navigation System (FOG-INS), dual GNSS antennas, and an odometer across two contrasting environments: a dense urban area with severe signal obstruction and an open-sky area with minimal GNSS obstruction. The analysis focused on yaw and positional differences between the two configurations to evaluate methodological implications and practical significance. Results indicate that in urban environments, the maximum difference in yaw values between single-antenna and dual-antenna processing was 0.107° with an average difference of 0.049° along the entire path and maximum positional differences in 2D and 3D about 1.931 meters and 2.245 meters, respectively. In contrast, for the second experiment (open-sky area), the maximum yaw difference was 0.008° with an average of 0.002°, and positional differences were limited to the millimeter range.  These findings demonstrate that dual-antenna configurations enhance the robustness and reliability of MMS data collection under degraded GNSS conditions, contributing to improved mapping performance and system stability. The outcomes of this research provide a practical framework for selecting antenna configurations and data acquisition strategies suited to varying environmental constraints, while future studies are encouraged to explore alternative coupling schemes and advanced algorithms to further optimize system accuracy.