A system for determining an angle α between a longitudinal axis of a vehicle and an authenticator, in particular a key or a keyless entry device for a vehicle, wherein the angle α can be calculated with the system using the formula α=(d.sub.r−d.sub.l).Math.k.sub.w, where d.sub.r is the calculated and/or measured distance to the authenticator from an antenna mounted on the right side in or on the vehicle, d.sub.l is the calculated and/or measured distance to the authenticator from an antenna mounted on the left side on the vehicle, and k.sub.w is a correction factor for the angle calculation that is established in a vehicle-specific manner.

A system for determining an angle α between a longitudinal axis of a vehicle and an authenticator, in particular a key or a keyless entry device for a vehicle, wherein the angle α can be calculated with the system using the formula α=(d.sub.r−d.sub.l).Math.k.sub.w, where d.sub.r is the calculated and/or measured distance to the authenticator from an antenna mounted on the right side in or on the vehicle, d.sub.l is the calculated and/or measured distance to the authenticator from an antenna mounted on the left side on the vehicle, and k.sub.w is a correction factor for the angle calculation that is established in a vehicle-specific manner.

A vehicle control system includes at least one control inceptor to provide pilot control of an associated vehicle and a communications interface to process external entity SA data associated with an external entity that is received at a communications system associated with the associated vehicle. An SA video screen displays video data to a pilot of the associated vehicle. The video data includes pilot-perspective visual data corresponding to a real-time dynamic virtual representation of surroundings of the associated vehicle that simulates a real-world visual perspective of the pilot to the surroundings of the associated vehicle and is responsive to the pilot control. A visual indicator of the external entity is superimposed onto the pilot-perspective visual data at an approximate location corresponding to an actual location of the external entity relative to the associated vehicle and beyond a visual range of the pilot based on the external entity SA data.

Techniques are disclosed for determining the presence of pulse jams in an identification friend or foe (IFF) system. In an embodiment, a plurality of jamming pulse rates are determined. Each of the plurality of jamming pulse rates is a count of jamming pulses entering the IFF system during a corresponding integration period. Each of the plurality of jamming pulse rates is a count of jamming pulses associated with non-valid signals entering the IFF system. An average jamming pulse rate is computed based on the plurality of jamming pulse rates. The average jamming pulse rate is then compared against a pulse jam threshold to determine whether a pulse jam is present (or not present) in the IFF system.

Techniques are disclosed for determining the presence of pulse jams in an identification friend or foe (IFF) system. In an embodiment, a plurality of jamming pulse rates are determined. Each of the plurality of jamming pulse rates is a count of jamming pulses entering the IFF system during a corresponding integration period. Each of the plurality of jamming pulse rates is a count of jamming pulses associated with non-valid signals entering the IFF system. An average jamming pulse rate is computed based on the plurality of jamming pulse rates. The average jamming pulse rate is then compared against a pulse jam threshold to determine whether a pulse jam is present (or not present) in the IFF system.

An apparatus for detecting a traffic participant includes a first detection device for detecting the traffic participant in a first detection zone. The first detection device is configured to repeatedly detect the first detection zone and to detect an entering of a traffic participant in the first detection zone, and/or to detect the traffic participant in an angular section in an extended first detection zone beyond the first detection zone according to an instruction. The apparatus also includes a second detection device that detects the traffic participant in a second detection zone, and is adapted to provide data required for instruction about the traffic participant in response to the detection of the traffic participant and to forward it to the first detection device for instruction. This way, the traffic participant may be detected by the first detection device before entering the first detection zone.

A method for detecting conflicts in the II/SI identification code of radars nearby a secondary mode-S radar, includes at least: a first step wherein the radar detects unsolicited unsynchronized replies, i.e. fruits, in a region of extended radar coverage; a second step wherein the radar detects a conflict in II/SI code by analyzing geographic regions of radar coverage common to the radar and to at least one nearby radar, a conflict being detected if the radar: detects, in the region of extended coverage, the presence of fruits that have as source the nearby radar; observes the absence of fruits caused by the nearby radar in that region of radar coverage of the radar which does not overlap with the region of radar coverage of the nearby radar; the region of overlap between the radar coverage of the radar and the radar coverage of the nearby radar forming a region of conflict in II/SI code.

A device and techniques for generating and filtering a signal for transmission, such as the signal used to interrogate distance measuring equipment (DME), which may be tuned to a channel or frequency selected from a wide bandwidth. A system according to the techniques of this disclosure may generate a narrow band intermediate frequency (IF) signal with desired pulse characteristics, mix the IF signal with a local oscillator (LO) to upconvert to the desired radio frequency (RF) signal, then filter the upconverted RF signal through one of several narrow band filters in a filter bank to remove any undesired signal images. The system may select the filter from the filter bank depending on the transmitted RF frequency. In this manner the system of this disclosure may generate signals to span a wide RF bandwidth by using a narrow bandwidth IF signal generator.

In a distance estimating system, a first terminal transmits a response request signal and successively transmits impulse signals as synchronization signals, and a second terminal receives the response request signal, generates response data based on the response request signal, shifts a bit, which is a transmission target in a bit string as the response data, by one toward a rear side from a leading bit to a trailing bit each time the synchronization signal is received, transmits the impulse signal in a case where a value of a bit that is a transmission target at a time of reception of the synchronization signal is a predetermined value. The first terminal further measures a round-trip time, specifies a flight time of the impulse signal, and estimates a distance to the second terminal based on the flight time and a propagation velocity of the impulse signal.

An identification friend or foe (IFF) transponder includes: an electronic receiver to receive encoded challenges from an IFF interrogator; a processing circuit including a decode circuit to decode the received challenges into encrypted challenges using a time of day (TOD) and/or a cryptographic key, a decrypt circuit to decrypt the encrypted challenges into challenges using the TOD and/or the key, a reply circuit to generate replies to the challenges, and an encode circuit to encode the generated replies using the TOD and/or the key; an electronic transmitter to transmit the encoded replies to the IFF interrogator; and an alert circuit to detect the encrypted challenges from the received challenges without using the TOD or the key, use the detected challenges to determine if the TOD is incorrect and/or the key is wrong, and issue an alert in response to determining the TOD is incorrect and/or the key is wrong.