GBAS and GLS
I had seen these terms before but I forgot what they meant. TL;DR, they are a new system of ground based augmentation that will improve navigation performance in the immediate vicinity of an airport. Currently only Newark and Houston-Hobby have the systems installed and the required equipment is installed on some Boeing aircraft flown by United Airlines.
Pilot Controller Glossary
GROUND BASED AUGMENTATION SYSTEM (GBAS) LANDING SYSTEM (GLS)- A type of precision IAP based on local augmentation of GNSS data using a single GBAS station to transmit locally corrected GNSS data, integrity parameters and approach information. This improves the accuracy of aircraft GNSS receivers’ signal in space, enabling the pilot to fly a precision approach with much greater flexibility, reliability and complexity. The GLS procedure is published on standard IAP charts, features the title GLS with the designated runway and minima as low as 200 feet DA. Future plans are expected to support Cat II and CAT III operations.
The FAA has a page describing the system.
Satellite Navigation – Ground Based Augmentation System (GBAS)
Ground-Based Augmentation System (GBAS) is a system that provides differential corrections and integrity monitoring of Global Navigation Satellite Systems (GNSS). GBAS provides navigation and precision approach service in the vicinity of the host airport (approximately a 23 nautical mile radius), broadcasting its differential correction message via a very high frequency (VHF) radio data link from a ground-based transmitter. GBAS yields the extremely high accuracy, availability, and integrity necessary for Category I, and eventually Category II, and III precision approaches. GBAS demonstrated accuracy is less than one meter in both the horizontal and vertical axis.