The main objective of the project is to assess the utilization of Factor Graph Optimization (FGO) for GNSS-based (Global Navigation Satellite Systems) positioning, navigation, and timing (PNT) determination. This picks up on recent research suggesting that the results from FGO are superior to those of conventional Bayes filters. As the basis for the evaluation, an FGO-based navigation engine and a corresponding testbed are to be implemented. The benchmark for the novel technique will then be obtained by analysing the results from a test campaign and from public data sets. Of special interest is the comparison of results to that from the Extended Kalman Filter (EKF) and output from COTS receivers.