Abstract: A control system in communication with one of an aircraft navigational aid system and an aircraft surveillance system is described. The control system obtains measurement data associated with radio frequency (RF) signals transmitted by the one of the aircraft navigational aid system and the aircraft surveillance system from an unmanned aerial vehicle (UAV) reporting the measurement data. The control system also determines whether the measurement data indicates the RF signals are within a range of values based on a location of the UAV in an airspace proximate to the one of the aircraft navigational aid system and the aircraft surveillance system. The control system further controls the RF signals transmitted by the one of the aircraft navigational aid system and the aircraft surveillance system based on the measurement data and the location of the UAV. Methods performed by the control system are also described.

Abstract: A fault tolerant, fail-active computer system comprises a Redundancy Management Unit (RMU) and a plurality of Dual-Port Message Buffers (DPBs) connecting each of a corresponding plurality of communication channels to the RMU. Each DPB includes a message channel interface, a dual-port RAM, a word counter, a page FIFO, a message header FIFO, and a message buffer control circuit. The RMU includes word comparators, 3-state gates, a message comparison control circuit, and a voted message FIFO. Under software control, the RMU and DPBs perform the functions of management of asynchronous redundant digital messages, sorting of redundant messages received in arbitrary order, synchronization of distributed computing elements, comparison of data words of arbitrary bit length, and configuration control of active channels and communication path redundancy.