Beacon Collision Avoidance System (BCAS) Alternative Concepts for Determing Target Positions.

摘要

The (Litchford) Beacon-based Collision Avoidance System concept requires the computation of target range and bearing relative to the BCAS aircraft. Techniques for determining target range and bearing under four different assumptions about the ground radar environment are reported. The systems considered are a fully passive BCAS system when there are two ground radars equipped with azimuth reference signals and a single target, two ground radars of which only one has azimuth reference signals and two targets, and two ground radars without ground reference signals and two targets as well as a BCAS system using both active range measurements and signals from a single ground radar. It is found that the error sensitivity of the solutions is a function of the geometry of the configuration. Multiple solutions are possible with systems involving only one target. A family of curves is derived and illustrated by examples to permit qualitative evaluation of the solution in any given configuration. (Author)