Abstract: A system and method for enhanced use of voltage standing wave ratio (VSWR) tests of an avionic radio and antenna is disclosed. A signal processor/generator conducts a VSWR test of an antenna and archives the result within a database. Multiple tests are conducted spanning periods of operation of the radio. Tests may also be conducted at multiple frequencies, such as commonly used channels of communication. Results are uploaded to an external diagnostic device and analyzed to evaluate deterioration of the antenna. Analysis may including comparing test results to threshold values and analyzing test results for frequency and time dependent trends.

Abstract: Systems and methods for selecting a ground station for air-ground communications are disclosed. In an embodiment, a system includes a communications device operable to maintain bi-directional communications between an aircraft and a selected ground station, and a communications processor coupled to the device that is configured to select the ground station by executing a logical rule that is based upon a signal strength value of the ground station and at least one of an aircraft altitude and an occupancy value of the frequency channel.

Abstract: System and method for the adaptive control of VHF communications in aircraft. In one embodiment, the invention includes an adaptive communications system for an aircraft having a communications processor that accesses a communications switching model to select a preferred ground communications station. In another embodiment, a method of communication between an aircraft and a ground station includes receiving a communications switching model and determining a flight parameter for the aircraft as the aircraft navigates along a flight route and selecting a ground station based upon the determined flight parameter. The aircraft then communicates with the selected ground station. In still another embodiment, a method for compiling a communications switching model includes receiving signals from a ground station and measuring a signal strength. A preferred ground station is selected based upon the measured signal strength value.