In GNSS-degraded environments, whether the degrada6on is naturally occurring (e.g., in deep urban canyons) or inten6onal (e.g., in the presence of a jammer or a spoofer), ambient radio frequency (RF) signals can be exploited as an alterna6ve posi6oning, naviga6on, and 6ming (PNT) source. These signals are commonly referred to as signals of opportunity (SOPs). SOPs can be terrestrial (e.g., cellular, digital television, and AM/FM transmitters) or space-based (e.g., low Earth orbit (LEO) satellites). This project studied various aspects of exploi6ng cellular terrestrial and LEO-based SOPs as an alterna6ve to GNSS for mul6-modal highly automated transporta6on systems (HATS). The studies spanned theore6cal analyses and modeling, extensive simula6ons, and real-world experimental demonstra6ons on ground vehicles, low-al6tude unmanned aerial vehicles (UAVs), and high attitude aircraft. Some studies were also conducted in a real-world GPS-jammed environment at Edwards Air Force Base, Mojave Desert, CA.
In GNSS-degraded environments, whether the degrada6on is naturally occurring (e.g., in deep urban canyons) or inten6onal (e.g., in the presence of a jammer or a spoofer), ambient radio frequency (RF) signals can be exploited as an alterna6ve posi6oning, naviga6on, and 6ming (PNT) source. These signals are commonly referred to as signals of opportunity (SOPs). SOPs can be terrestrial (e.g., cellular, digital television, and AM/FM transmitters) or space-based (e.g., low Earth orbit (LEO) satellites). This project studied various aspects of exploi6ng cellular terrestrial and LEO-based SOPs as an alterna6ve to GNSS for mul6-modal highly automated transporta6on systems (HATS). The studies spanned theore6cal analyses and modeling, extensive simula6ons, and real-world experimental demonstra6ons on ground vehicles, low-al6tude unmanned aerial vehicles (UAVs), and high attitude aircraft. Some studies were also conducted in a real-world GPS-jammed environment at Edwards Air Force Base, Mojave Desert, CA.