Dr. Hsu completes visiting researcher position at Google

Dr. Li-Ta Hsu completed his 20-month visiting researcher position at Google from January 2023 to August 2024, working with the Android Context team on smartphone positioning and GNSS improvements. The Android Context team is responsible for the location and context-sensing capabilities that underpin location services across the Android ecosystem, serving billions of devices worldwide. This extended collaboration provided a rare opportunity for direct academic-industry engagement on one of the most impactful applied problems in navigation: delivering accurate, reliable positioning on mass-market consumer smartphones.

Smartphone GNSS positioning in urban environments is particularly challenging due to signal multipath, non-line-of-sight reception caused by tall buildings, and the limited antenna and front-end performance of mobile devices compared to dedicated GNSS receivers. Dr. Hsu brought to Google his deep expertise in urban GNSS positioning, including techniques for multipath and NLOS detection, 3D mapping-aided positioning, and non-Gaussian error modeling, all of which are central research themes at the Intelligent Positioning and Navigation Laboratory (IPNL). The collaboration allowed these academic research methods to be evaluated and adapted within the context of a large-scale production system.

During the visiting period, Dr. Hsu contributed to efforts aimed at improving the accuracy and robustness of Android location services, particularly in dense urban canyons where conventional positioning methods struggle. The work built on the availability of raw GNSS measurements through the Android API, which enables advanced measurement-level processing and algorithm development directly on smartphone hardware.

The completion of this visiting position marked a significant milestone for both Dr. Hsu and IPNL, strengthening the laboratory’s ties with industry and informing ongoing research directions. The collaboration has continued through a subsequent Google Unrestricted Research Grant awarded to IPNL, supporting further work on smartphone GNSS positioning.