Broadcast Positioning System (BPS): Resilience and Precision

BPS Mesh Network Initial Deployment Report  - $15

The BEIT 2024 paper, ATSC 3.0 Broadcast Positioning System (BPS) Mesh Network [3], provided a description of a notional mesh network intended to manage and monitor a collection of ATSC 3.0 television transmissions intended to provide high precision traceable time. A preliminary network of these Broadcast Positioning System (BPS) transmissions has been constructed in the Baltimore and Washington DC region using two transmitters and a third simulated transmitter in the NAB 1M laboratory. Another BPS transmitter has been deployed in the Denver area to reach the NIST facility in Boulder, Colorado where the signal is being analyzed.

This paper describes the actual systems deployed, how they are operating, and the results of the various experiments being carried out using the first installation of a BPS leader / follower architecture in preparation for a fully operational network deployment.

In addition, the paper describes the initial implementation of a network operating software system which has been developed with the intention of supporting a large, perhaps nation-wide deployment of the BPS Mesh Network.

Mark Corl | Triveni Digital, Inc. | Princeton, N.J., United States
Vladimir Anishchenko | Avateq Corp. | Markham, Ontario, Canada
Tariq Mondal | National Association of Broadcasters | Washington, D.C., United States

Field test of ATSC 3.0/BPS precise time distribution  - $15

The Broadcast Positioning System (BPS™) is a protocol for high-resolution time transfer between a reference clock at a ATSC 3.0 transmitter and a BPS receiver’s disciplined-clock output. Time transfer is a prerequisite for (and useful by-product of) positioning/navigation systems such as Global Navigation Satellite Systems (GNSS); for example, the Global Positioning System (GPS). In principle, BPS may address potential vulnerabilities in critical applications with GNSS dependence, mostly due to relatively weak GNSS signal levels at Earth’s surface. In 2024, BPS was added to the ATSC 3.0 transmission of the station KWGN in the Denver, Colorado metropolitan area. To measure BPS time transfer stability, BPS receivers were installed at two NIST campuses (the furthest: 106 km away) and compared against independent local atomic clock timescales. As an example, over one 50-day period and a non-line-of-sight (NLOS) transmission path of 30 km that includes terrain obstruction, we observed peak-to-peak time deviations on the order of tens of nanoseconds (including all variation of the reference time scales), a stability roughly comparable with ubiquitously deployed, single-band GPS receivers.

Jeff A. Sherman, David A. Howe | Time and Frequency Division, National Institute of Standards and Technology | Boulder, Colo., United States

Transferring traceable time to BPS-enabled ATSC 3.0 station - $15

Broadcast Positioning System (BPS) necessitates precise time synchronization across TV stations, utilizing a shared time reference and their fixed locations for triangulation and reliable positioning, with time over fiber solutions connected to trusted timing sources serving as a viable method for maintaining accurate synchronization. In this paper, we present a concept to link BPS leader stations to timescales maintained by National Metrology Institutes (NMIs) using High Accuracy White Rabbit synchronization through optical networks.

Francisco Girela Lopez, Ramki Ramakrishnan | Safran Electronics and Defense | Rochester, N.Y., United States