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.

Abstract: A passive radiation sensor suitable for homeland security applications or other monitoring of locations deemed at high risk to radiation exposure. The sensor further incorporates a method to provide a statistically derived detection threshold algorithm that guarantees a predetermined and configurable false-alarm rate and rapid detection of low-level radiation.

Abstract: An airborne telecommunications network uses airborne aircraft to route message traffic between a source and destination.

Abstract: A battering ram for forcible entry through a door has a pointed end with barbs to enable the door to be hooked and pulled outward. The barbs will swing between contracted and expanded positions. This spring biases the barbs to the expanded position. The barbs are conical and define a cone with the same taper as the pointed tip when the barbs are collapsed. One end of the battering ram may have a loop for attaching to a line connected to a vehicle. Also, one end of the battering ram may have a battering plate or may have a bar for prying burglar bars outward.