Performance verification of GNSS/5G tightly coupled fusion positioning in urban occluded environments with a smartphone

Although GNSS (Global Navigation Satellite System) is well-established for outdoor positioning, it still encounters challenges in urban occluded environments. Currently, multi-source fusion positioning has emerged as the primary solution. Since commonly used smartphones can simultaneously receive satellite signals and send 5G signals, researching GNSS/5G fusion positioning based on smartphones is a highly feasible solution. However, existing studies on GNSS/5G fusion positioning primarily rely on simulation data and TOA (Time of Arrival). On the one hand, simulation data often fail to accurately reflect positioning performance in real-world environments. On the other hand, while TOA often struggles to achieve high accuracy due to time synchronization errors, the AOA (Angle of Arrival) method, which does not depend on time synchronization, presents a promising alternative. Therefore, we propose a GNSS/5G tightly coupled fusion positioning method based on AOA measurements and conduct practical tests. For the first time, we use a smartphone to verify the performance of this method in urban occluded environments. The static experimental results indicate that SPP of the smartphone performs poorly in occluded environments. In contrast, AOA positioning demonstrates relatively stable performance. GNSS/5G fusion positioning yields the best positioning results, exhibiting a best improvement of 98.18% over SPP and 70.69% over AOA positioning. For the two dynamic routes with varying levels of occlusion, GNSS/5G fusion positioning shows considerable enhancements, achieving improvements of 39.39% and 9.32% over SPP, and 13.35% and 44.68% over AOA positioning. These results demonstrate that the fusion positioning method can effectively compensate for the shortcomings of satellite positioning in occluded environment.