Abstract: Methods and systems for imaging a target. In some examples, a system includes an optical modulator configured for applying, at each time of an exposure window, a respective optical modulation pattern to a received image of the target to output a modulated image. The system includes a camera configured for capturing a single image frame for the exposure window by receiving, at each of time, the modulated image of the target. The system includes a demodulator implemented on a computer system and configured for demodulating the single image frame based on the optical modulation patterns to recover a number of recovered image frames each depicting the target at a respective recovered time within the exposure window.

Abstract: An adaptive interrogation method is provided, the method including determining application of an adaptive whisper shout interrogation sequence. The determination may be predictive and based on an anticipation of garbled replies or may be reactive and based on a plurality of replies to an initial ATCRBS interrogation, there being interference between the replies such that the replies are unable to be properly decoded. The adaptive whisper shout interrogation sequence includes adapting a subsequent ATCRBS interrogation. The adaptation may be a change in an amplitude difference between an interrogation pulse and a suppression pulse of the subsequent ATCRBS interrogation (i.e. a bin width), as compared to the initial ATCRBS interrogation; or the adaptation may be a change in a power of the subsequent ATCRBS interrogation as compared to the initial ATCRBS interrogation. The subsequent ATCRBS interrogation is then transmitted, and one or more replies are received.

Abstract: Various communication systems may benefit from enhanced reception methods. For example, various transponders and surveillance systems may benefit from reception methods that can distinguish between overlapping pulses from multiple sources. A method can include receiving, at an antenna, a first series of pulses from a first source. The method can also include receiving, at the antenna, a second series of pulses from a second source. The first series and the second series can at least partially overlap each other. The method can further include de-interleaving the first series from the second series using at least one non-time-domain technique.

Abstract: Various communication systems may benefit from enhanced reception methods. For example, various transponders and surveillance systems may benefit from reception methods that can distinguish between overlapping pulses from multiple sources. A method can include receiving, at an antenna, a first series of pulses from a first source. The method can also include receiving, at the antenna, a second series of pulses from a second source. The first series and the second series can at least partially overlap each other. The method can further include de-interleaving the first series from the second series using at least one non-time-domain technique.

Abstract: A system determines bearing for situational awareness. The system may include a receiver, a processor, and a memory comprising an engine for performing a method. The method includes receiving signals using directional reception; receiving positional data; calculating a correction amount; and applying the correction amount to subsequent uncorrected bearings to provide corrected bearings. Positional data may be received in any conventional format including data link, ADS-B, and MODE S. Positional data may be determined in the target using a global positioning system. The system may provide a signal to display the corrected bearing and/or provide traffic alerting and collision avoidance advisories.

Abstract: The present invention provides an apparatus, method, and computer-executable program for detecting antenna failures in directional antennas. In particular, the present invention compares a bearing calculated from received positional data concerning a target to the bearing of the target determined using the directional antenna. If the calculated bearing and the determined bearing differ by greater than a predetermined amount, it is determined that there is an antenna failure. In this way, bearing information determined by the directional antenna is compared against a piece of known data in order to determine if the antenna is functioning properly.

Abstract: A Traffic Alert and Collision Avoidance System(TCAS) antenna is mounted on a selected forward portion of an aircraft thereby extending the effective forward range of the TCAS. The antenna and ground plane are tilted relative to conventional TCAS antennas thereby aligning a peak of the antenna's radiation pattern along the aircraft's level line of flight. The resulting increased gain directed forward of the aircraft increases the forward range of the TCAS for both receiving and transmitting TCAS signals. The invention is also useful to extend the range of other aircraft systems including transponders. Alternate embodiments include tilting a conventional TCAS antenna mounted on a middle portion of the aircraft.