🤖 AI Summary
Low GNSS positioning accuracy for mobile devices in urban environments—caused by multipath effects, signal occlusion, and ranging errors from low-cost hardware—is addressed in this work. We propose NeRC, an end-to-end neural network framework. Its key contributions are: (1) a differentiable moving-window position estimation module that eliminates reliance on ground-truth ranging error labels; (2) a differentiable moving horizontal estimation (MHE) mechanism enabling effective gradient backpropagation; and (3) a cost-map training paradigm based on Euclidean distance fields (EDFs), reducing annotation overhead while supporting joint optimization. Evaluated on both public and custom-built urban datasets, NeRC achieves significant improvements in localization accuracy over state-of-the-art methods. Furthermore, it is successfully deployed on edge devices, demonstrating real-time performance and practical viability.
📝 Abstract
GNSS localization using everyday mobile devices is challenging in urban environments, as ranging errors caused by the complex propagation of satellite signals and low-quality onboard GNSS hardware are blamed for undermining positioning accuracy. Researchers have pinned their hopes on data-driven methods to regress such ranging errors from raw measurements. However, the grueling annotation of ranging errors impedes their pace. This paper presents a robust end-to-end Neural Ranging Correction (NeRC) framework, where localization-related metrics serve as the task objective for training the neural modules. Instead of seeking impractical ranging error labels, we train the neural network using ground-truth locations that are relatively easy to obtain. This functionality is supported by differentiable moving horizon location estimation (MHE) that handles a horizon of measurements for positioning and backpropagates the gradients for training. Even better, as a blessing of end-to-end learning, we propose a new training paradigm using Euclidean Distance Field (EDF) cost maps, which alleviates the demands on labeled locations. We evaluate the proposed NeRC on public benchmarks and our collected datasets, demonstrating its distinguished improvement in positioning accuracy. We also deploy NeRC on the edge to verify its real-time performance for mobile devices.