# Modified RTK-GNSS for Challenging Environments

## TL;DR

This paper improves RTK-GNSS accuracy in urban areas by using surplus satellites to detect errors, outperforming existing commercial and open-source solutions.

## Contribution

A novel technique that uses surplus satellites to enhance RTK-GNSS reliability in challenging environments.

## Key findings

- The proposed method achieved a higher fix rate than commercial and open-source RTK-GNSS solutions.
- Positional reliability was improved to levels comparable to or exceeding commercial technology.
- Tests were conducted in densely built-up areas of Tokyo, demonstrating real-world effectiveness.

## Abstract

Real-Time Kinematic Global Navigation Satellite System (RTK-GNSS) is currently the premier technique for achieving centimeter-level accuracy quickly and easily. However, the robustness of RTK-GNSS diminishes in challenging environments due to severe multipath effects and a limited number of available GNSS signals. This is a pressing issue, especially for GNSS users in the navigation industry. This paper proposes and evaluates several methodologies designed to overcome these issues by enhancing the availability and reliability of RTK-GNSS solutions in urban environments. Our novel approach involves the integration of conventional methods with a new technique that leverages surplus satellites—those not initially used for positioning—to more reliably detect incorrect fix solutions. We conducted three tests in densely built-up areas within the Tokyo region. The results demonstrate that our approach not only surpasses the fix rate of the latest commercial receivers and a popular open-source RTK-GNSS program but also improves positional reliability to levels comparable to or exceeding those of the aforementioned commercial technology.