Prof. Geng attended ION GNSS+ 2018 which held in Miami, USA from September 24 to 29. He gave two talks titled "Inter-GNSS PPP ambiguity resolution: Implementation and benefits exemplified by tightly-coupled GPS and BeiDou" and "A comprehensive assessment of raw multi-GNSS measurements from mainstream portable smart devices". Prof. Geng also chaired the session for high-precision GNSS on Friday morning.