Abstract: This disclosure is directed to systems and methods for aircraft collision avoidance with speed-based collision alert time thresholds. In one example, a system is configured to determine predicted trajectories for an own aircraft and a target aircraft. The system is further configured to determine whether a violation of protected airspace is predicted between the own aircraft and the target aircraft. The system is further configured to determine whether a predicted time to closest approach between the own aircraft and the target aircraft is less than an alert threshold time based on a speed of the own aircraft. The system is further configured to generate an alert output, in response to determining that a violation of protected airspace is predicted and that the predicted time to closest approach between the own aircraft and the target aircraft is less than the alert threshold time based on the speed of the own aircraft.

Abstract: In some examples described herein, a runway location is determined based on aircraft state information from at least one aircraft. For example, a processor may determine the coordinates of one or more points of a runway based on aircraft state information generated by one or more aircraft using the runway. In some examples, the processor may aggregate coordinates determined from the aircraft state information provided by a plurality of different aircraft in order to determine the location of the runway. The processor can be located onboard an aircraft providing the state information, onboard a different aircraft, or external to any aircraft.

Abstract: Provided are methods and systems for the automatic calculation and presentation of data on a display device alerting a pilot that a change in flight plan is desirable, possible and administratively compliant under air traffic control protocol. The methods and systems may automatically request the flight clearance over a data link or the pilot may override the data link.

Abstract: An integrated transceiver system for an avionics radio comprises a first transceiver comprising a first duplexer coupled with a first antenna, a first transmitter that sends an RF signal to the first duplexer, a first receiver that receives an RF signal from the first antenna through the first duplexer, and a first processor in communication with the first transmitter. The first transceiver is reconfigurable for ATG communications or DME navigation. A second transceiver comprises a second duplexer coupled with a second antenna, a second transmitter that sends an RF signal to the second duplexer, a second receiver that receives an RF signal from the second antenna through the second duplexer, and a second processor in communication with the second receiver. The second transceiver is reconfigurable for ATG communications, DME navigation, transponder signal communications, or satellite communications. The first and second transceivers are integrated into a line-replaceable unit of the radio.

Abstract: Systems and methods for calculating coherent bearing that allow one to reduce the number of TCAS antenna elements. In one embodiment, the bearing calculation takes into account signal-to-noise ratio (SNR) difference experienced from top and bottom antennas mounted on a vehicle.

Abstract: Systems and methods for improving bearing initialization for a pair of two-element antennas. An exemplary system includes two-element antennas mounted on the bottom and top of an aircraft fuselage, an output device, and a processing device. The processing device receives phase-difference information based on phase of signals received at each element of a two-element antenna, determines if the received phase-difference information is within a predefined low-confidence region, and initializes bearing if the phase-difference information is not within the low-confidence region or the phase-difference information from a predefined number of consecutively received signals meets a predefined consistency requirement.

Abstract: Systems and methods for improving bearing availability and accuracy in a traffic collision-avoidance system (TCAS). In an exemplary method, if only a single phase-difference value is received for one of two two-element antennas, a processor determines an expected maximum antenna element phase-difference value for the elements of the two-element antenna that did not receive a phase-difference value for a target signal source; estimates a phase-difference value for the two-element antenna that did not include a phase-difference value, based on the expected maximum antenna element phase-difference value and a previously determined predicted bearing value; and calculates bearing based on the estimated phase-difference value and a phase-difference value received from the other two-element antenna.

Abstract: In some examples described herein, a runway location is determined based on aircraft state information from at least one aircraft. For example, a processor may determine the coordinates of one or more points of a runway based on aircraft state information generated by one or more aircraft using the runway. In some examples, the processor may aggregate coordinates determined from the aircraft state information provided by a plurality of different aircraft in order to determine the location of the runway. The processor can be located onboard an aircraft providing the state information, onboard a different aircraft, or external to any aircraft.

Abstract: Systems and methods that allow for distance-measuring equipment (DME) to use either a lower or an upper fuselage-mounted antenna. An exemplary system located on an aircraft includes an aircraft configuration data source that generates aircraft configuration information, an aircraft orientation data source that generates aircraft orientation information, a positioning system that generates aircraft position information and a component that provides DME ground station position information. The system also includes a first antenna, a second antenna and a processing device that determines if a DME signal communication issue exists with the first antenna that is based on the generated aircraft position information, the DME ground station position information and at least one of the configuration or orientation information. The processing device switches DME signal communication to the second antenna if a DME signal communication issue has been determined to exist.

Abstract: Systems and methods for improving the presentation of wake turbulence information. A processor located on an ownship receives position, heading and type information of another aircraft and position and heading information of the ownship. The processor determines if a possible wake condition exists from the other aircraft based on at least a portion of the received information and at least one predefined threshold and generates a wake icon if a wake condition is determined to exist. The wake condition exists when the ownship's altitude is below a first threshold altitude and above a second threshold altitude, wherein the first and second threshold altitudes are based on the other aircraft's altitude.

Abstract: A two-element array antenna system includes a first antenna element and a second antenna element. A transmitting, receiving, and processing (TRP) system is coupled to the first and second antenna elements via, respectively, a single first transmission element and a single second transmission element. The first and second transmission elements have respective transmit-path and receive-path functionality. The TRP system is configured to determine an amplitude offset and phase offset associated with the transmit-path functionality of the first and second transmission elements, and, based on data obtained during the determination of amplitude offset and phase offset associated with the transmit-path functionality of the first and second transmission elements, determine an amplitude offset and phase offset associated with the receive-path functionality of the first and second transmission elements.

Abstract: Systems and methods for improving bearing availability and accuracy in a traffic collision-avoidance system (TCAS). In an exemplary method, if only a single phase-difference value is received for one of two two-element antennas, a processor determines an expected maximum antenna element phase-difference value for the elements of the two-element antenna that did not receive a phase-difference value for a target signal source; estimates a phase-difference value for the two-element antenna that did not include a phase-difference value, based on the expected maximum antenna element phase-difference value and a previously determined predicted bearing value; and calculates bearing based on the estimated phase-difference value and a phase-difference value received from the other two-element antenna.

Abstract: Systems and methods for calculating coherent bearing that allow one to reduce the number of TCAS antenna elements. In one embodiment, the bearing calculation takes into account signal-to-noise ratio (SNR) difference experienced from top and bottom antennas mounted on a vehicle.

Abstract: Systems and methods for improving bearing initialization for a pair of two-element antennas. An exemplary system includes two-element antennas mounted on the bottom and top of an aircraft fuselage, an output device, and a processing device. The processing device receives phase-difference information based on phase of signals received at each element of a two-element antenna, determines if the received phase-difference information is within a predefined low-confidence region, and initializes bearing if the phase-difference information is not within the low-confidence region or the phase-difference information from a predefined number of consecutively received signals meets a predefined consistency requirement.

Abstract: Systems and methods for improving the presentation of wake turbulence information. A processor located on an ownship receives position, heading and type information of another aircraft and position and heading information of the ownship. The processor determines if a possible wake condition exists from the other aircraft based on at least a portion of the received information and at least one predefined threshold and generates a wake icon if a wake condition is determined to exist. The wake condition exists when the ownship's altitude is below a first threshold altitude and above a second threshold altitude, wherein the first and second threshold altitudes are based on the other aircraft's altitude.

Abstract: Systems and methods that allow for distance-measuring equipment (DME) to use either a lower or an upper fuselage-mounted antenna. An exemplary system located on an aircraft includes an aircraft configuration data source that generates aircraft configuration information, an aircraft orientation data source that generates aircraft orientation information, a positioning system that generates aircraft position information and a component that provides DME ground station position information. The system also includes a first antenna, a second antenna and a processing device that determines if a DME signal communication issue exists with the first antenna that is based on the generated aircraft position information, the DME ground station position information and at least one of the configuration or orientation information. The processing device switches DME signal communication to the second antenna if a DME signal communication issue has been determined to exist.

Abstract: System, method and computer program product for determining bearing using ADS-B and TCAS standard reply bearing estimates are disclosed. In one embodiment, a method for determining bearing based upon ADS-B signals includes receiving ADS-B signals and standard transponder reply signals. A first bearing estimate is based on the ADS-B signal. A second bearing estimate is based on the standard transponder reply signals. A database is developed according to the first and second bearing estimates via the ADS-B and standard transponder reply signals. In one embodiment, where ADS-B signals are unavailable, associated ADS-B signals associated with the standard transponder reply previously stored in the database are used to determine bearing.

Abstract: A two-element array antenna system includes a first antenna element and a second antenna element. The first and second antenna elements respectively include first and second frequency multipliers. A transmitting, receiving, and processing (TRP) system is coupled to the first and second antenna elements via, respectively, a single first transmission element and a single second transmission element. The TRP system is configured to transmit to the first antenna element a first input signal at a sub-multiple of a first frequency, receive from the first frequency multiplier a first calibration signal based on the first input signal, transmit to the second antenna element a second input signal at a sub-multiple of the first frequency, receive from the second frequency multiplier a second calibration signal based on the second input signal, and determine, based on the calibration signals, a relative phase difference between the first and second transmission elements.

Abstract: A two-element array antenna system includes a first antenna element and a second antenna element. A transmitting, receiving, and processing (TRP) system is coupled to the first and second antenna elements via, respectively, a single first transmission element and a single second transmission element. The first and second transmission elements have respective transmit-path and receive-path functionality. The TRP system is configured to determine an amplitude offset and phase offset associated with the transmit-path functionality of the first and second transmission elements, and, based on data obtained during the determination of amplitude offset and phase offset associated with the transmit-path functionality of the first and second transmission elements, determine an amplitude offset and phase offset associated with the receive-path functionality of the first and second transmission elements.

Abstract: A direction finding antenna system for determining the relative bearing of a second aircraft from a first aircraft in conjunction with Distance Measuring Equipment (DME). The system includes a first antenna and a second antenna located on a top surface of the first aircraft, spaced apart along a first axis, as well as a third antenna and a fourth antenna located on a bottom surface of the first aircraft, spaced apart along a second axis orthogonal to the first axis. The system further includes a transmitting, receiving, and processing system coupled to the first, second, third, and fourth antennas, wherein the transmitting, receiving, and processing system is configured to transmit DME interrogations, receive DME replies, and process the DME replies to determine the relative bearing of the second aircraft from the first aircraft.