Convolutional Neural Network for Multipath Detection in GNSS Receivers
This work addresses multipath contamination in GNSS positioning for navigation systems, but it is incremental as it adapts existing CNN methods to a new domain.
The paper tackled multipath detection in GNSS receivers by applying a convolutional neural network (CNN) to correlator output signals, achieving detection through automated feature extraction from 2D-mapped data.
Global Navigation Satellite System (GNSS) signals are subject to different kinds of events causing significant errors in positioning. This work explores the application of Machine Learning (ML) methods of anomaly detection applied to GNSS receiver signals. More specifically, our study focuses on multipath contamination, using samples of the correlator output signal. The GPS L1 C/A signal data is used and sourced directly from the correlator output. To extract the important features and patterns from such data, we use deep convolutional neural networks (CNN), which have proven to be efficient in image analysis in particular. To take advantage of CNN, the correlator output signal is mapped as a 2D input image and fed to the convolutional layers of a neural network. The network automatically extracts the relevant features from the input samples and proceeds with the multipath detection. We train the CNN using synthetic signals. To optimize the model architecture with respect to the GNSS correlator complexity, the evaluation of the CNN performance is done as a function of the number of correlator output points.