The ATSC 3.0 NextGen TV standard defines a precise time stamp of the emission time of each broadcast frame. The time stamp, along with the transmitting antenna location, can be used to determine the distance of the receiver from the transmitter. If at least three such ATSC 3.0 transmissions are available in an area, these broadcasts can be used as a precise positioning system, called a Broadcast Positioning System (BPS) , which can be used as a backup system for the Global Positioning System (GPS).
However, providing a precise time stamp is technically challenging due to various delays and variability in the broadcast transmission studio processing chain. This paper describes a proof-of-concept system, developed by multiple partner companies under the direction of NAB Pilot, that provides a closed loop time stabilization system. The paper explores the techniques used to measure the broadcast signal’s emission time and to compensate for the processing chain timing variability stabilizing the emission time stamp. The paper also describes the lessons learned and the barriers to further improve the timing accuracy of the BPS system.
Mark T. Corl | Triveni Digital, Inc | Princeton, New Jersey, United States
Vladimir Anishchenko | Avateq Corp. | Markham, Ontario, Canada
Tariq Mondal | National Association of Broadcasters | Wasington, District of Columbia, United States