MAE Seminar – Precise Positioning, Navigation, and Timing (PNT)

Details

MAE Seminar – Precise Positioning, Navigation, and Timing (PNT)

Tuesday, February 27, 2024, at 12:50pm, Location: MAE-A 303

Dr. Jian Yao, Scientist, National Center for Atmospheric Research (NCAR/UCAR), Adjunct Associate Professor, Colorado State University

Abstract
Positioning, Navigation, and Timing (PNT) is a vital area for people’s daily life, high-tech, satellite industry, and military usage. Historically, this area originated from a fundamental question – where we are in the universe – which was addressed by observing the star locations in the sky and more importantly the periodic motions of the Sun and the Moon. Nowadays, this area is dominated by the Global Navigation Satellite System (GNSS), including the U.S.-built Global Positioning System (GPS). I will review the basic principle of GNSS and then discuss how to achieve the centimeter-level accuracy & precision for ground and space navigation. I will talk about some of my research work, such as the generation of the GNSS satellite ephemerides, GNSS time dissemination, the generation of the U.S. standard time incorporating optical clocks, precise orbit determination (POD), and the application of POD towards atmospheric density sensing for space collision avoidance. The future PNT directions/applications will also be discussed.

Biography
Dr. Jian Yao is a scientist at the University Corporation for Atmospheric Research (UCAR), which manages the National Center for Atmospheric Research (NCAR). There, he works on the orbits & clocks of GNSS (Global Navigation Satellite System) and LEO (low-Earth-orbit) satellites and applies precise satellite orbits & clocks to GNSS radio occultation and atmospheric density sensing. He is also an adjunct associate professor at Colorado State University where he teaches the GNSS courses and supervises graduate students. He used to work at the U.S. National Institute of Standards and Technology (NIST) and NOAA’s National Geodetic Survey, both under the U.S. Department of Commerce, for many years. He has published ~ 40 papers covering a variety of topics in the area of positioning, navigation, and timing (PNT), such as GNSS satellite ephemeris, GNSS data processing, precise orbit determination, GNSS time transfer, and atomic-clock timing systems. In 2014, he received a Ph.D. degree from the University of Colorado at Boulder.

MAE Faculty Host: Dr. John Conklin