Hybrid GNSS and Street Level Station Ranging Positioning

The patent combines GNSS satellite-based ranging with terrestrial Street Level Station (SLS)-based ranging to create a hybrid positioning system. The user device performs both GNSS measurements and SLS ranging measurements, then fuses these measurements to compute position. This merging compensates for GNSS weaknesses in urban environments by adding a terrestrial reference system that is not affected by satellite geometry or multipath effects from satellites.

Street Level Stations act as intermediary reference points between the user device and the global positioning system. Instead of relying solely on distant satellites, the system introduces local SLS intermediaries that provide stable, ground-based ranging references. These intermediaries mitigate the harmful effects of urban canyons and multipath propagation by providing direct line-of-sight or controlled propagation paths for ranging signals.

The patent replaces complex vision-based image processing with simpler radio-frequency or optical ranging measurements. Instead of capturing and processing images to extract feature points and compute relative position, the system uses time-of-flight or phase-based ranging signals to directly measure distance to SLSs. This substitution dramatically reduces computational complexity while maintaining or improving positioning accuracy.

The system changes the measurement parameter from image data (complex, high-dimensional) to ranging measurements (simple, scalar distance values). By transitioning from visual feature matching to direct distance measurement via signal time-of-flight or phase difference, the computational burden is reduced from complex image processing algorithms to straightforward distance calculation and trilateration.