Patent Description:
Traffic control centers, such as in airfield control towers, are commonly positioned on the airfield for purposes of controlling movement of aircraft both on the airfield and in airspace in the vicinity of the airfield. Positioning the control tower at the airfield allows human controllers operating from the control tower to have situation awareness as to aircraft movements on and around the airfield. Proximity to the air traffic itself has traditionally provided the advantage that the human controllers can visually see aircraft moving on the airfield and in the immediate vicinity of the airfield. Prior art in this field includes <CIT> and <CIT>.

With the proliferation of sensors it has become possible to move the functions provided by the airfield human controller off the airfield and to locations remote from the airfield. Moving the human controllers off the airfield frees space at the airfield for other uses, improving the efficiency of airfield operations. Such traffic control towers typically include imaging devices that communicate live imagery of airfield activity to the remote location, allowing the human controllers to control airfield operations from a secure location and monitor activity. This reduces the airfield footprint and leaves the human air traffic controllers less exposed to threats.

Such conventional methods and systems have generally been considered satisfactory for their intended purpose. However, there is still a need in the art for improved identification systems for digital air traffic control centers, airfield digital air traffic control centers, and air traffic object identification methods. The present disclosure provides a solution for this need.

In accordance with an aspect of the invention there is provided an identification system for a digital air traffic control center as claimed in claim <NUM>. Various embodiments of this aspect of the invention are provided in claims dependent from claim <NUM>.

In accordance with another aspect of the invention there is provided an air traffic object identification method as claimed in claim <NUM>.

Reference will now be made to the drawings wherein like reference numerals identify similar structural features or aspects of the subject disclosure. For purposes of explanation and illustration, and not limitation, a partial view of an exemplary embodiment of an air traffic identification system for a digital air traffic control center in accordance with the disclosure is shown in <FIG> and is designated generally by reference character <NUM>. Other embodiments of air traffic identification systems, civil and military airfields having digital air traffic control center with air traffic identification systems, and methods of identifying air traffic objects in accordance with the disclosure, or aspects thereof, are provided in <FIG>, as will be described. The systems and methods described herein can be used for identifying air traffic objects, such as in remote digital air traffic control centers for civil and military airfields, though the present disclosure is not limited to remote digital air traffic control centers or to air traffic object identification in general.

The human eye responds to light within the visible portion of the electromagnetic spectrum. Visible light is generally understood to have wavelengths between about <NUM> nanometers and about <NUM> nanometers. Electromagnetic radiation with wavelengths below <NUM> nanometers is generally described as ultraviolet radiation. Electromagnetic radiation with wavelengths above <NUM> nanometers is generally described as infrared radiation.

The infrared portion of the electromagnetic spectrum is typically divided into the near-infrared (NIR) infrared spectrum portion, the short-wave infrared (SWIR) infrared spectrum portion, the mid-wave infrared (MWIR) infrared spectrum portion, and the long-wave (LWIR) infrared spectrum portion. As used herein, NIR refers to electromagnetic radiation with a wavelength between about <NUM> microns and about <NUM> micron. SWIR refers to electromagnetic radiation with a wavelength between about <NUM> microns and about <NUM> microns. MWIR refers to electromagnetic radiation with a wavelength between about <NUM> microns and <NUM> microns. LWIR refers to electromagnetic radiation with a wavelength between about between about <NUM> microns and <NUM> microns.

Referring to <FIG>, an airfield <NUM> is shown. Airfield <NUM> includes one or more runways <NUM>, a ramp <NUM>, and a digital air traffic control center <NUM>, e.g., a remote digital control tower. Digital air traffic control center <NUM> is configured and adapted for controlling the movement of air traffic objects <NUM> on ramp <NUM> and the one or more runways <NUM> of airfield <NUM> as well as in environs <NUM> of airfield <NUM>, environs <NUM> as used herein meaning within the effective field of view of digital air traffic control center <NUM>. Airfield <NUM> also includes a sensor <NUM> with a pulse detection array <NUM> having a field of view <NUM> spanning at least a portion of environs <NUM>, ramp <NUM>, and the one or more runways <NUM>. It is contemplated that digital air traffic control center <NUM> be remote from airfield <NUM>, remote meaning that operators at digital air traffic control center <NUM> are unable to directly view airfield <NUM> without the aid of remote sensors, e.g., sensor <NUM>.

One or more air traffic objects <NUM> located on ramp <NUM>, runways <NUM>, and in environs <NUM> carry a pulsed illuminator <NUM>. The pulsed illuminator <NUM> is configured and adapted to emit pulsed illumination in predetermined waveband and modulated with information identifying the respective air traffic object <NUM>. It is contemplated that the pulsed illuminator <NUM> be optically coupled to the sensor <NUM> for communicating the identity of air traffic object <NUM> at relatively long range, e.g., outside of visible range and/or through an atmospheric obscurant <NUM>. Examples of atmospheric obscurants include fog, haze, and smog by way of non-limiting examples.

Sensor <NUM> is configured and adapted for acquiring image data <NUM> of a scene including at least a portion of environs <NUM>, ramp <NUM>, and the one or more runways <NUM>. Image data <NUM> is provided to an air traffic object recognition module <NUM> (shown in <FIG>), which recognizes air traffic objects <NUM> according to size or shape. Pulse detection array <NUM> is configured and adapted for acquiring pulse data <NUM> emitted from pulsed illuminators <NUM> carried by air traffic objects <NUM>, which pulse detection array <NUM> provides to an air traffic object identification module <NUM> (shown in <FIG>), which air traffic object identification module <NUM> uses to identify air traffic control objects <NUM>, e.g., by tail number.

In certain embodiments airfield <NUM> can be a terrestrial airfield. Examples of terrestrial airfields include general aviation and commercial airfield installations. In accordance with certain embodiments, airfield <NUM> can be a marine airfield. Examples of marine airfields include small deck and large deck military aircraft carriers, landing pads on military and commercial marine vessels, and landing facilities on fixed marine structures like oil drilling and exploration platforms. Air traffic objects <NUM> can include fixed wing aircraft, rotary wing aircraft, and/or autonomous air vehicles, as suitable for a given application.

Sensor <NUM> is co-located with airport <NUM> and has a field of view <NUM> encompassing at least a portion of the airfield <NUM> and environs <NUM>. For example, sensor <NUM> can be mounted on a mast or gimbal structure <NUM>. Mast of gimbal structure <NUM> can be fixed or can provide pan, tilt, and/or zoom capability to sensor <NUM>. As will be appreciated by those of skill in the art in view of the present disclosure, use of a mast or gimbal structure can increase size of field of view <NUM>. In this respect it is contemplated that as few as one sensor <NUM> provide coverage sufficient such that image data <NUM> is representative, and timely, to safely control movement of air traffic objects <NUM> on airfield <NUM> as well as in environs <NUM> of airfield <NUM> by recognizing the respective air traffic object type. Further, it is also contemplated as few as one pulse detection array <NUM> provide coverage sufficient such that pulse data <NUM> provide identification information for controlling the timely and safe movement of air traffic objects <NUM> on airfield <NUM> as well as in environs <NUM> of airfield <NUM> according to identify of individual air traffic objects <NUM>.

As shown with the dashed line indicating data link <NUM>, it is contemplated that digital air traffic control center <NUM> be remote from airfield <NUM> and include air traffic identification system <NUM>. In this respect digital air traffic control center <NUM> can located away from airfield <NUM>, e.g., outside of the field of view <NUM> of sensor <NUM>. Placing digital air traffic control center <NUM> at a remote location frees space on airfield <NUM> for airfield operations, improving airfield efficiency. Placing digital air traffic control center <NUM> at a remote location can also reduce the resources necessary to secure digital air traffic control center <NUM>, such as by co-siting identification system <NUM> and its users with other assets requiring security.

Referring to <FIG>, sensor <NUM>, pulse detection array <NUM>, and pulsed illuminator <NUM> are shown according to exemplary embodiments. Air traffic objects <NUM> each carry a pulsed illumination modulation module <NUM> and a pulsed illuminator <NUM>. Pulsed illumination modulation module <NUM> is operatively associated with pulsed illuminator <NUM> and is arranged to cause pulsed illuminator to emit pulsed illumination in a predetermined waveband or sub-waveband. Pulse detection array <NUM> and sensor <NUM> are configured and adapted to generate both image data <NUM>, for air traffic object recognition using illumination reflected from air traffic objects, and pulse data <NUM>, for identification of individual air traffic objects using pulsed illumination emitted by pulsed illuminator <NUM>.

For example, as shown in <FIG>, in certain embodiments, air traffic object <NUM> can carry a visible waveband pulsed illuminator 116A. Visible waveband pulsed illuminator 116A is arranged to emit visible waveband pulsed illumination <NUM> according to modulation information provided by illumination modulation module <NUM>. Visible waveband pulse detection array 103A, individually and/or in cooperation with the sensor <NUM>, generates image data <NUM> and pulse data <NUM> for recognizing and identifying air traffic object <NUM> using visible waveband pulsed illumination <NUM>.

As shown in <FIG>, in accordance with certain embodiments, air traffic object <NUM> can carry an infrared pulsed illuminator 116B. Infrared pulsed illuminator 116B is arranged to emit infrared waveband pulsed illumination <NUM> according to modulation information provided by illumination modulation module <NUM>. Infrared waveband pulse detection array 103B, individually and/or in cooperation with the sensor <NUM>, generates image data <NUM> and pulse data <NUM> for recognizing and identifying air traffic object <NUM> using infrared waveband pulsed illumination <NUM>.

As shown in <FIG>, in accordance with certain embodiments, air traffic object <NUM> can carry an MWIR sub-waveband pulsed illuminator 116C. MWIR pulsed illuminator 116C is arranged to emit MWIR pulsed illumination <NUM> according to modulation information provided by illumination modulation module <NUM>. MWIR pulse detection array 103C, individually and/or in cooperation with the sensor <NUM>, generates image data <NUM> and pulse data <NUM> for recognizing and identifying air traffic object <NUM> using MWIR pulsed illumination <NUM>.

As shown in <FIG>, in accordance with certain embodiments, air traffic object <NUM> can carry an LWIR sub-waveband pulsed illuminator 116D. LWIR pulsed illuminator 116D is arranged to emit LWIR pulsed illumination <NUM> according to modulation information provided by illumination modulation module <NUM>. LWIR pulse detection array 103D, individually and/or in cooperation with the sensor <NUM>, generates image data <NUM> and pulse data <NUM> for recognizing and identifying air traffic object <NUM> using LWIR pulsed illumination <NUM>.

As shown in <FIG>, it is also contemplated that air traffic object <NUM> can carry a SWIR illuminator 116E. SWIR pulsed illuminator 116E is arranged to emit SWIR pulsed illumination <NUM> according to modulation information provided by illumination modulation module <NUM>. SWIR sub-waveband pulse detection array 103E, individually and/or in cooperation with the sensor <NUM>, generates image data <NUM> and pulse data <NUM> for recognizing and identifying air traffic object <NUM> using SWIR pulsed illumination <NUM>. As will be appreciated by those of skill in the art in view of the present disclosure, the use of infrared waveband illumination to generate image data <NUM> (shown in <FIG>) and pulse data <NUM> has the benefit of improved visibility when imaging through an atmospheric obscurant <NUM>, e.g., dust, haze, smog, and smoke. Improved visibility in turn allows for recognition of air traffic objects <NUM> at relatively long ranges, thereby extending the effective depth of field of view <NUM> of sensor <NUM>. This is particularly true in the case of SWIR pulsed illumination, which can extend the identification range out beyond that of the sensing range of co-sited air traffic control centers.

With reference to <FIG>, identification system <NUM> is shown. Identification system <NUM> includes a processor <NUM>, a data interface <NUM>, a user interface <NUM>, and a memory <NUM>. Processor <NUM> is disposed in communication with data interface <NUM>, and therethrough with sensor <NUM> to receive therefrom image data <NUM> via data link <NUM>. Processor <NUM> is also disposed in communication with user interface <NUM> for operative connection of user interface <NUM> for displaying an image <NUM> of airfield <NUM> (shown in <FIG>).

Memory <NUM> has a plurality of program modules having instructions recorded thereon that, when read by processor <NUM>, cause processor <NUM> to execute certain operation, e.g., the operations of an air traffic object identification method <NUM>, as will be described. Among the modules are an air traffic object recognition module <NUM>, to recognize shape <NUM> of air traffic objects on and in the environs of the airfield, and air traffic object identification module <NUM>, to determine the identify <NUM> of air traffic objects on and in the environs of the airfield. It is contemplated that identification system <NUM> be implemented using circuitry, software, or a combination of both software and circuitry, as suitable for an intended application.

With reference to <FIG>, air traffic object identification method <NUM> is shown. Air traffic object identification method <NUM> includes emitting pulsed illumination, e.g., pulsed illumination <NUM>-<NUM> (shown in <FIG>), as shown with box <NUM>. The pulsed illumination is modulated to include information identifying an individual air traffic object, as shown with box <NUM>. In certain embodiments the pulsed illumination can be within a visible wavelength waveband, as shown with box <NUM>. In accordance with certain embodiments, the pulsed illumination can be within an infrared wavelength waveband, as shown with box <NUM>. It is also contemplated that the pulsed illumination can be within an infrared sub-waveband, such as LWIR, MWIR, and/or SWIR wavebands, as shown with boxes <NUM>-<NUM>.

Air traffic object identification method <NUM> also includes receiving the pulsed illumination at a sensor, e.g., pulse detection array <NUM> (shown in <FIG>) and/or sensor <NUM> (shown in <FIG>), as shown with box <NUM>. The pulsed illumination is demodulated, as shown with box <NUM>, and the air traffic object identified based on the information contained in the modulated illumination, as shown with box <NUM>. The identity of the air traffic object is displayed on a user interface, e.g., user interface <NUM> (shown in <FIG>), as shown with box <NUM>. The user interface can be located remotely from an airfield while displaying at least a portion of the airfield and/or airfield environs, as shown in in <FIG> in exemplary image (or video) <NUM>. The aircraft is also recognized using illumination received at the sensor, as shown with box <NUM>, such as with a shape recognition algorithm or similar utility, providing the flexibility to integrate air traffic objects without pulsed illuminator and/or in operative pulsed illuminators, as shown with box <NUM>. The shape recognition is displayed with the aircraft identity, as shown with box <NUM>.

Commercial and military air traffic control is moving away from brick-and-mortar air traffic control towers and towards digital air traffic control centers. Digital imaging sensors mounted on a mast can improve the visibility that digital air traffic control center have by transmitting live imagery to air traffic controllers in a secure facility. This reduces on-airport footprint and leaves air traffic controllers less exposed to threats.

In embodiments described herein pulse detection arrays and pulsed emitters are employed to further improve visibility in digital air traffic control centers. In accordance with certain embodiments, pulse detection arrays and pulsed emitters are employed that employ SWIR, MWIR, and/or LWIR illumination to aircraft identification in digital air traffic control center. The identification can be augmented by with object recognition to facilitate one-and two-way communication between aircraft and between aircraft and digital air traffic control center. For example, pulsed LED infrared emitters carried on aircraft and a SWIR imager with pulse-detection pixel technology can be mounted on a mast with pan, tilt, and/or zoom capability. Such SWIR imagers can outperform visible sensors on hazy days for recognition purpose and the pulse detection capability will detect and positively identify distant aircraft at long-ranges. It is contemplated that this will allow for long-range, autonomous imaging and identification of aircraft with low rates of false-positive or false-negatives. Infrared imaging also has the benefit that, when employed in an environment having heavy atmospheric obscurants (dust, haze, smog, smoke), and the pulse detection array paired with pulsed illumination can provide long-range detection and identification of objects such as aircraft.

Claim 1:
An identification system (<NUM>) for a digital air traffic control center (<NUM>), comprising:
one or more air traffic objects (<NUM>) carrying a pulsed illuminator (<NUM>) arranged for emitting pulsed illumination (<NUM>);
a pulsed illumination modulation module (<NUM>) operatively associated with the pulsed illuminator (<NUM>) and configured to modulate pulsed illumination (<NUM>) emitted by the pulsed illuminator (<NUM>) with an air traffic object identity;
a sensor (<NUM>) with a pulse detection array (<NUM>) and having a field of view (<NUM>);
a user interface (<NUM>) to display the one or more air traffic objects (<NUM>) in the field of view (<NUM>) of the sensor (<NUM>); and
a controller having:
an air traffic object recognition module (<NUM>), disposed in communication with the sensor (<NUM>), configured to receive image data (<NUM>) and recognize the one or more air traffic objects (<NUM>) according to shape using the image data (<NUM>); and
an air traffic object identification module (<NUM>), disposed in communication with the pulse detection array (<NUM>), configured to receive pulse data (<NUM>),
wherein:
the air traffic object identification module (<NUM>) is configured and adapted to identify the one or more air traffic objects (<NUM>) using the pulsed illumination (<NUM>) emitted by the pulsed illuminator (<NUM>) carried by the air traffic objects (<NUM>) within the field of view (<NUM>) of the sensor (<NUM>);
the pulse detection array (<NUM>) and the sensor (<NUM>) are configured and adapted to generate both the image data (<NUM>) for air traffic object recognition by the air traffic object recognition module (<NUM>), and the pulse data (<NUM>) for identification of individual air traffic objects (<NUM>) by the air traffic object identification module (<NUM>); and
the user interface (<NUM>) is configured to display both the identity (<NUM>) and the shape (<NUM>) of the one or more air traffic objects (<NUM>) in the field of view (<NUM>) of the sensor (<NUM>).