Implementation and Test of a Low Cost GBAS Subset Airborne Receiver Experimental Platform for UAVs

Abstract

A Ground Based Augmentation System (GBAS) provides differential corrections to Global Navigation Satellite Systems (GNSS) using VHF Data Broadcast (VDB) Equipment. This paper discusses development and test of an experimental low cost single frequency (GPS L1) GBAS airborne subset receiver. The objective of the design is to serve as a research platform for implementation and testing of different measurement processing architectures and integrity monitoring algorithms suitable for new potential user types such as small Unmanned Aerial Vehicles (UAVs). Following a brief discussion of platform architecture and component selection, preliminary results from a field test carried out near to the Zurich airport with its operational GBAS Approach Service Type (GAST) C GBAS station are presented. We describe an experimental low cost prototype receiver to implement GBAS with adaptive carrier smoothing for a single frequency Global Positioning System (GPS) and VDB receiver. Our results demonstrate how low cost GNSS receiver sensitivity can be increased to make it more robust, and viable via additional signal analyses focused on the receiver RF block’s messages.