Patent Description:
An airport shares real time information with arriving and departing aircraft over many communication channels. Voice communication is widely used to communicate weather information such as visibility, wind speed and direction, precipitation, and atmospheric pressure, used to set an aircraft's altimeter. Weather information may be recorded or automated and repeatedly broadcasted on the automatic terminal information service (ATIS). An airport may have a voice radio channel dedicated to the ATIS for that airport. An airport also uses voice communication to tell a departing aircraft which taxiway and runway to use while on the ground and may also communicate potential hazards in the area, such as ground vehicles or animals. Air traffic control may use voice communication for aircraft approaching for landing to direct aircraft movements into a landing pattern, instruct which instrument approach to use, instruct which runways to use, and for providing other such directions. With voice communications, only one person may speak at a time for a given channel, resulting in limited bandwidth, especially at busy airports or during emergencies.

Other real-time communication channels include high speed communication links such as broadband and satellite. Although efficient, current communication links suffer from challenges such as limited coverage area, periodic unavailability of communication link, and increasing demand for bandwidth in today's aircraft. Factors important in communication links include data speed, cost, and reliability of the communication link. In some examples, flight data may be shared between aircraft using ground systems because of the high bandwidth requirements.

<CIT> discloses A runway identification system including a weather radar system. The weather radar system includes a receiver. The receiver is configured to receive a runway characteristic signal from a transponder associated with a runway. The runway identification system determines a runway identification based on the runway characteristic signal. <CIT>, discloses a radar system that has an antenna. The system includes electronics configured to facilitate communication using radar returns received and transmitted by the antemla. The electronics is configured to extract communications data from a received radar return. The electronics is further configured to provide communications data with an outgoing radar pulse for data transmission. <CIT>discloses a system and method for detecting and viewing aircraft hazardous incidents such as flying aircraft and meteorological phenomena which includes microbursts, thunderstorms, tornadoes, and the wake turbulence of aircraft. The aircraft hazardous incidents are positionally and horizontally displayed to the pilot on a display, that is located in the aircraft cockpit, in relation to the flight path of the aircraft. The displaying of the aircraft hazardous incidents may permit the pilot to take evasive action to avoid a potentially dangerous incident.

<CIT> describes a radar displaying system and method for use in displaying weather radar information on a cockpit display of an aircraft. The system receives onboard weather radar information from an on-board weather radar system and ground-based weather radar information up-linked to the aircraft from a ground-based weather radar system. The information from the on-board weather radar system and the information from the ground-based weather radar system are combined to generate composite weather radar information. In response to the composite information, the cockpit display simultaneously displays both on-board weather radar imagery and ground-based weather radar imagery.

<CIT> describes a method including electronically scanning, by an antenna of an aircraft, an environment of the aircraft. The electronically scanning can include transmitting or receiving an electrical frequency over the antenna. The antenna can include a negative index of refraction meta-material. The electronically scanning can also include applying an electric field to control a dielectric constant of the antenna.

<CIT> describes an aircraft having an X-band avian radar detection and warning system. The system can include an X-band radar system and a processor. The processor can include a target processor module that can process the reflected X-band radar signals to: detect targets in a projected flight path of the aircraft; identify one or more targets that are determined to correspond to one or more birds; and generate a bird detection signal. In response to receiving the bird detection signal, the warning generator module can generate and transmit a warning generator signal to at least one cockpit output device in the cockpit of the aircraft to cause it to generate a warning signal that is perceptible in the cabin of the aircraft to warn pilots and crew of a potential collision with the birds so that the pilot can take evasive action.

<CIT> describes an onboard weather radar system that generates image data representative of an external scene topography of a runway environment associated with radar returns received by the onboard weather radar system. The radar returns are in an X-band or a C-band. The enhanced vision system also includes a display in communication with the onboard weather radar system and is configured to display an image associated with the image data that is generated by the onboard weather radar system. The enhanced vision system can also be used as an enhanced flight vision system.

<CIT> describes a radar system including electronics configured to receive communications from a terrestrial location. The communications can include composite weather data from a plurality of sources and scheduling data. The scheduling data can include an indication of timing for sending local weather data sensed by an airborne radar system to the terrestrial location. The terrestrial system can provide composite weather radar data to an airborne source.

<CIT> describes a horizontally polarized antenna apparatus which forms an omnidirectional pattern in the horizontal plane. The radiation field in the horizontal plane becomes continuous and a horizontally polarized omnidirectional radiation pattern can be obtained in the horizontal plane by forming radiation slots at opposing positions on a grounded hollow body and exciting the slots out of phase.

<CIT> describes an airborne vehicle lighting control apparatus and method for automatically controlling activation and deactivation of an airborne vehicle lighting system. A processor for automatically controlling the lighting system can be employed and has one or more sensors operatively connected to the processor for sensing the current flight operating mode and geographical position of an airborne vehicle. The processor can activate or deactivate lighting based on the current flight operating mode and position.

The invention is defined in the attached independent claims to which reference should now be made. Further, optional features may be found in the sub-claims appended thereto.

This disclosure is directed to weather radar configured to act as a communication device to allow real-time data communication. This disclosure describes techniques for using a weather radar on board an aircraft as a high bandwidth X-band radio for communication. The X-band weather radar, onboard an aircraft, may be used for receiving flight related data and weather-related data while also acting as a weather radar. As the weather radar is already present on many aircraft, particularly commercial aircraft, the techniques of this disclosure may, in some scenarios, be implemented without a need for additional hardware, devices, or equipment onboard the aircraft to meet the data communication needs
According to the techniques of this disclosure, an airport may utilize an X-band data transmitter to broadcast digital data to aircraft in the vicinity of the airport. The X-band data transmitter and the weather radar systems of airplanes at the airport may engage in a one-to-many communication session, such that multiple weather radar systems on multiple planes receive the digital data being broadcast by the airport. The X-band data transmitter may receive the digital data from a data conversion interface unit that collects information from other systems at or near an airport. Some of these systems may include systems that collect weather information such as an Automated Weather Observing System (AWOS), lightning detector, and predictive wind shear system (PWS). The weather-related systems may provide digitized information on wind speed and direction, air pressure, wind shear hazard areas, precipitation, and similar information.

Other systems on or near an airport may provide situational awareness information of interest to the X-band data transmitter, which in turn may relay such information to arriving or departing aircraft. This information may include the location of possible hazards on the ground or in the air such as animals or birds near the airport, the location of other aircraft taxiing to and from the airport runways, and the location of ground vehicles. The data conversion interface may receive information from these other systems and broadcast this information in a data stream included in a signal transmitted by the X-band data transmitter. Existing X-band weather radar systems onboard aircraft in the vicinity of the airport may act as an X-band radio to receive the data stream containing the information from these airport systems. A pilot on the aircraft may choose to display any or all of the information from the data stream. For example, a pilot may choose to display the PWS and avian hazard areas, but rely on the aircraft's own lightning detection system to display lightning location.

Other channels such as voice communication, satellite communication links, cellular data links, or similar communication channels are currently used for transmitting these types of information. Shifting information flow to X-band weather radar systems acting as an X-band radio may reduce the bandwidth needs of other channels such as voice communication or satellite links. For example, if an incoming aircraft pilot can receive and display the location of potential wind shear hazards via the X-band radio channel, then the airport control tower may be able to avoid using limited voice channel airtime to describe the wind shear locations. This may allow the voice communication channel, along with other data link channels, to have more bandwidth available for other functions.

The use of weather radars on aircraft as a data communication device, i.e. an X-band radio, has several other possible advantages. The additional X-band radio channel may augment the data transfer requirements of other communication links. An X-band radio has the capability to transmit at high data rates. The design of data communication mode in the weather radar is configured to allow maximum bandwidth usage to transmit data at high rates while still allowing full use of the weather radar to detect and display weather information. The large beam width of the weather radar allows wide coverage area at longer distances. The weather radar is available for operation as soon as the aircraft powers on the radar during preparation for takeoff and is available for data communication needs. Converting an existing weather radar system to add an X-band radio function requires no additional hardware or equipment for the aircraft. A modification in firmware/software of the weather radar may alone be sufficient for using the weather radar as a communication device.

In contrast, some complex communication systems may use other types of data links to transfer data to and from an aircraft. These types of complex communication systems may include scheduling units to date and time stamp data, unlike the less complex X-band radio channel. These complex communication systems may allow data fusion to combine information from ground stations or other aircraft to be fused into a single display. These complex communication systems may have advantages in providing information to an aircraft, such as aircraft <NUM>, that may be outside the range of weather radar system 40B onboard aircraft <NUM>. However, these complex communication systems have a disadvantage in requiring installation of complex hardware that may include scheduling units to time stamp and manage data flow for data fusion. Complex communication systems, such as those in use or proposed at present, would need to be installed in new aircraft and back fitted into older aircraft, which may be a significant cost to aircraft operators. Also, these complex systems may consume additional bandwidth by transmitting detailed weather and other information over data links that may be expensive and already filled close to capacity. Pushing additional data on a crowded bandwidth may require more bandwidth sharing and therefore the situational awareness information may be slow to download. An X-band radio channel using existing weather radar may offer some advantages over a more complex communication system in some situations.

<FIG> is a conceptual diagram illustrating an example airport that includes an X-band data transmitter in accordance with one or more techniques of this disclosure. <FIG> also depicts examples of aircraft that include weather radar systems modified to receive X-band radio data while operating on or near an airport.

Airport <NUM> of <FIG> includes an X-band data transmitter <NUM> with an omnidirectional antenna <NUM>. X-band data transmitter <NUM> connects to the various systems that provide situational awareness information to pilots, as depicted by the connection to air traffic control (ATC) tower <NUM>. Aircraft <NUM>, with weather radar system 40A is conducting ground operations, such as taxi to or from a runway. Aircraft <NUM> with weather radar system 40B may be approaching or departing airport <NUM>. Aircraft <NUM> is an aircraft without a weather radar system, such as a smaller general aviation aircraft.

The example of <FIG> depicts X-band data transmitter <NUM> connected to ATC tower <NUM>. A data conversion interface within, or coupled to, X-band data transmitter <NUM> receives and converts aircraft position information received from ATC radar <NUM>, as well as information from other systems located on or near airport <NUM>. In some examples, ATC radar <NUM> may be called airport surveillance radar (ASR). X-band data transmitter <NUM> may be installed in ATC tower <NUM>, as shown in the example of <FIG>. In other examples, X-band data transmitter <NUM> may be installed anywhere near airport <NUM> that allows adequate coverage of the data stream broadcast through omnidirectional antenna <NUM>. For example, X-band data transmitter <NUM> and omnidirectional antenna <NUM> may be installed on a hill near airport <NUM> to prevent blocking or masking the data stream signal by the hill.

Aircraft <NUM>, conducting ground operations, may receive information through weather radar system 40A that is acting as an X-band radio receiver. In some examples aircraft <NUM> may operate weather radar system 40A with the weather radar functions turned off while on the ground. In these examples, weather radar system 40A may act as an X-band radio receiver without simultaneously operating as a weather radar. The pilot of aircraft <NUM> may choose to display information to assist ground situational awareness. For example, the pilot of aircraft <NUM> may display the location of ground vehicles or other aircraft on the ground, which may come from an airport surface detection system, such as ground control radar. If departing, aircraft <NUM> may also display weather information. This may include the air pressure, to set the aircraft altimeter, wind speed and direction, visibility, and other weather-related information.

Aircraft <NUM> may be arriving, departing or just flying near airport <NUM>. In the example of aircraft <NUM> making an approach to airport <NUM>, the pilot of aircraft <NUM> may choose to display airport weather information received by weather radar system 40B operating as an X-band radio receiver. The pilot of aircraft <NUM> may choose to display the location of potential wind shear or bird strike hazards received in the data stream through X-band radio. In some examples, aircraft <NUM> may not include a PWS or avian radar system such as may be installed at airport <NUM>. In the example above, aircraft <NUM> and aircraft <NUM> may receive the same signal, and thus be able to display the same information, potentially subject to pilot preference.

Aircraft <NUM> may not include a weather radar. Smaller aircraft, such as some general aviation aircraft or light sport aircraft may not include weather radar systems. Aircraft without a weather radar system, such as aircraft <NUM>, may still take advantage of the additional situational awareness provided by the techniques of this disclosure. For example, by installing a simple X-band radio receiver unit on aircraft <NUM>, aircraft <NUM> may be able to receive information received by aircraft <NUM> and aircraft <NUM>. The X-band radio receiver unit may include an omnidirectional X-band receiving antenna and circuitry for down converting and decoding the X-band data signal sent by X-band data transmitter <NUM>. The X-band radio receiver circuitry in this example may extract the data stream from the signal broadcast by X-band data transmitter <NUM>. In some examples, the X-band radio receiver unit may include a display output that may connect to an existing display unit within aircraft <NUM>, such as a multi-function display (MFD) unit or a portable display such as a tablet computer. In other examples, the X-band radio receiver unit may include an integrated display unit. The X-band radio receiver circuitry may convert the data stream into an alert signal that may cause a display unit to present a representation of the alert signal. This representation may include information from the data stream for presentation to the pilot of aircraft <NUM>. Either the MFD, tablet computer or integrated display may allow the pilot of aircraft <NUM> to select and display information decoded from the data stream broadcast by X-band data transmitter <NUM>. In some examples, the alert signal may be converted into an auditory message that may be played to the pilot. For example, an auditory message may be presented to the pilot that says, "warning, wind shear area within <NUM> of current position.

Aircraft operating on or near an airport may include large commercial aircraft to small light sport aircraft. Aircraft have a wide variety of systems available to provide pilots situational awareness. Large commercial aircraft may have sophisticated weather radar, lightning detection and other systems. However, even large aircraft may not include avian detection or PWS systems. Currently, aircraft may receive additional information to aid in situational awareness via data links from satellite, cellular networks, and similar data links.

For many existing aircraft, adding an X-band radio capability to an existing weather radar system according to the techniques of this disclosure may require no data fusion or additional hardware or equipment on the aircraft. Instead, in some implementations, an aircraft may be configured to perform the techniques of this disclosure through an update to the firmware and/or software of the existing weather radar onboard the aircraft. The software and/or firmware update may add, to the existing weather radar of the aircraft, the functionality of using the weather radar as an X-band communication device.

An airport using the techniques of this disclosure may need to install some additional hardware. An airport, for example, may need to add an X-band data transmitter unit, such as X-band data transmitter <NUM>, along with omnidirectional antenna <NUM> to broadcast the X-band data stream. The X-band data transmitter unit may receive information from other airport systems that may not be available onboard an aircraft. An X-band data transmitter, as described by this disclosure, may reduce the bandwidth load on other communication channels, such as the complex communication channels above, voice communication and satellite data links. An X-band communication system according to the techniques of this disclosure may provide information such as weather information from AWOS, lightning information and position information of other aircraft. This may free these other channels, such as the complex data fusion channel above, to provide faster data transfer for information either not available from airport detection systems, or more suitable for data fusion, such as raw weather radar data.

Aircraft, such as aircraft <NUM> - <NUM> may receive position information via other systems such as automatic dependent surveillance - broadcast (ADS-B). However, ADS-B may not be installed on everything that may be a potential hazard to an aircraft either approaching an airport or during ground operations. For example, ground vehicles or animals, such as deer, wild pigs or loose livestock will not be shown by ADS-B. Other airport systems, such as ground surveillance systems, avian detection systems etc. may detect the presence and location of these other hazards. An X-band data transmitter, according to the techniques of this disclosure, may provide additional situational awareness to pilots through a high speed X-band data channel.

<FIG> is a block diagram illustrating an example system to broadcast information to aircraft using an X-band data transmitter in accordance with one or more techniques of this disclosure. Other example systems may include more, fewer, or different components than shown in the example of <FIG>.

System <NUM> may broadcast information to aircraft on or near an airport from various airport detection systems. System <NUM> may include information from one or more airport detection systems, convert the information into a data stream and communicate to aircraft in the vicinity of the airport by broadcasting the data stream over an X-band radio. The aircraft may receive the X-band radio data stream using an X-band weather radar that is functioning as an X-band radio receiver and as a weather radar.

System <NUM> includes an X-band data transmitter <NUM> connected to omnidirectional antenna <NUM>. X-band data transmitter <NUM> and omnidirectional antenna <NUM> perform the same functions as X-band data transmitter <NUM> and omnidirectional antenna <NUM> shown in <FIG>. X-band data transmitter <NUM> retrieves information from various airport detection systems. The airport detection systems shown in <FIG> include an AWOS <NUM>, terminal Doppler weather radar (TDWR) <NUM>, avian detection system <NUM>, ATC radar <NUM>, airport ground tracking system <NUM> and PWS <NUM>. Example system <NUM> may include more, fewer or different airport detection systems than those depicted by <FIG>. In some examples, system <NUM> may include lightning detection, ADS-B, or other detection systems not shown in <FIG>.

X-band data transmitter <NUM> may include data conversion unit <NUM>, X-band data upconverter <NUM> and low power X-band transmitter <NUM>. The components of X-band data transmitter <NUM> retrieve information from the various airport detection systems and convert the information into a data stream that is compatible with the data decoding firmware/software in the weather radar onboard an aircraft, such as weather radar systems 40A and 40B described in <FIG> above. X-band data transmitter <NUM> may receive the information from the various airport detection systems via a variety of means. Some airport detection systems may connect to X-band data transmitter <NUM> via a data communication interface. A data communication interface may include Ethernet, optical cable, wireless communication or similar interface used to transfer data.

Example X-band data transmitter <NUM> shown in <FIG> is one possible implementation. In some examples data conversion unit <NUM> and X-band data upconverter <NUM> may be combined in a single block that is communicatively coupled to the data communication interface. In the example where data conversion unit <NUM> and X-band data upconverter <NUM> are a single block, the input to this block may be information from one or more airport detection systems, such as TDWR <NUM>. The output is X-band data, where X-band data is an X-band carrier signal modulated with the data stream that includes information from one or more airport detection systems. Other examples of X-band data transmitter <NUM> may include different arrangements of functional blocks.

Data conversion unit <NUM> receives information from the one or more airport detection systems through the data communication interface. Each airport detection system may output its data in a format particular to the detection system. For example, TDWR <NUM> and PWS <NUM> may output the location of weather features in their own particular data format. As another example, different manufacturers of PWS systems, such as PWS <NUM> may choose somewhat different formats to output predicted wind shear area locations. Data conversion unit <NUM> receives data from the airport detection system in the format as sent by the airport detection system. In one example, data conversion unit <NUM>, may convert the coordinates given by the airport radar systems (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) into pre-processed coordinates which can be manipulated by the receiving weather radars for correct positional display of the artifacts of different weather or other hazards on the respective aircraft displays. The respective aircraft displays may include an MFD or other display as well as an auditory message as described above. Data conversion unit <NUM> is configured to convert a wide variety of data related to weather, lightening, wind shear, bird flocks, animals and ground obstacles into suitable global coordinates which can be finally displayed on the respective aircraft display after the weather radar receives the data.

X-band data upconverter <NUM> receives the data stream from data conversion unit <NUM>. X-band data upconverter <NUM> modulates an X-band carrier signal to load the data stream into the X-band carrier signal. In some examples, X-band data upconverter <NUM> may modulate a baseband carrier signal, then up-convert the baseband carrier through one or more stages of carrier multiplication and associated filtering until the modulated carrier signal reaches X-band frequency. The modulated carrier signal containing the data stream may be considered X-band data. X-band data upconverter <NUM> sends the modulated carrier signal to low power X-band transmitter <NUM>.

Low power X-band transmitter <NUM> filters and amplifies the X-band data and transmits the amplified X-band data to omnidirectional antenna <NUM>. In other words, low power X-band transmitter <NUM> amplifies the X-band carrier signal, which includes the modulated data stream containing information from the airport detection systems. Low power X-band transmitter <NUM> is configured to broadcast the X-band data with power low enough so that it is enough to cover the vicinity of the airport and does not reduce the sensitivity of the radars operating nearby. For this disclosure, the "vicinity" of an airport may be considered approximately ten nautical miles. The precise distance may vary depending on line-of-sight, interference from structures and land masses such as mountains, as well as atmospheric conditions and other factors.

AWOS <NUM> collects weather information on or near an airport. AWOS <NUM> is a type of automated airport weather station. Other types of automated airport weather stations include automated surface observing system (ASOS) and automated weather sensor system (AWSS). These automated sensor suites provide meteorological observations for aviation and other operations, including weather forecasting. AWOS <NUM> may provide information such as visibility, cloud cover and ceiling, temperature, humidity, barometric air pressure and runway wind direction and speed, precipitation, similar measurements. In some examples AWOS <NUM> includes lightning detection. AWOS <NUM> may output weather information through the data communication interface to data conversion unit <NUM>.

TDWR <NUM> is a network of terminal Doppler weather radar systems. These Doppler radar systems are used primarily for the detection of hazardous wind shear conditions, precipitation, and winds aloft on and near major airports. Many TDWR systems may be located in regions that have climates with thunderstorms. TDWR <NUM> may output weather information in data blocks that may include header and data sections. In some examples the data sections are compressed and may need decompression software tools to decompress and decode. One example format may include the Network Common Data Format (NetCDF), which is a set of data formats that support the sharing of scientific data.

Avian detection system <NUM> detect avian targets over airport operating areas and in some examples outside the fence to protect against bird strikes that may damage aircraft and injure birds. Some examples of avian detection system <NUM> include radar, cameras and processing software for detection, location, tracking and target classification of birds. Examples of radar may include S-band rotating radars and non-rotating electronically steered radars. In some examples the processing software in avian detection system <NUM> may combine infrared and electro-optical cameras with radar detection to confirm the location and movements of birds near an airport. A bird strike prevention system may include an avian detection system that also has the capability to cause birds to move away from the airport. Avian detection system <NUM> may output bird location information such as bird flock location coordinates through the data communication interface to data conversion unit <NUM>.

ATC radar <NUM> detects and tracks the location of aircraft for air traffic controllers to provide air traffic separation for collision avoidance and efficient movement of aircraft. In addition to the radar return from aircraft, ATC radar <NUM> may receive transponder replies that include aircraft identification, altitude and other information. Examples of ATC radar <NUM> include radars for local airport traffic and radars that track aircraft transiting the airspace between airports. ATC radar <NUM> may output airborne aircraft location coordinates, altitude, direction, speed or other information to the data communication interface. Data conversion unit <NUM> is configured to convert some or all of this information to be broadcast by X-band data transmitter <NUM>.

Airport ground tracking system <NUM> may include visual observation from an airport control tower as well as surface movement radar (SMR) or surface movement guidance and control systems (SMGCS) to track vehicles and aircraft on the maneuvering area such as taxiways and runways. In some examples airport ground tracking system <NUM> may also include cameras, movement detectors or similar items to detect wildlife or livestock that may have entered an airport. A deer or cow on a runway can be a significant hazard to aircraft. Airport ground tracking system <NUM> may output location information of potential hazards to data conversion unit <NUM> via the data communication interface. Some examples may include aircraft taxi location coordinates, ground vehicle location, and location of other hazards.

Complex, commercial turbine aircraft may include an airborne predictive wind shear system, but other aircraft, such as some turboprop aircraft may not. PWS <NUM> may include a low-level wind shear alert system (LLWAS) or similar systems installed at an airport to detect vertical and horizontal components of wind shear. A vertical wind shear may create turbulence while a horizontal wind shear may result in a cross wind or sudden change from headwind to tailwind. PWS <NUM> may output coordinate locations of geographic areas where wind shear is likely. These locations are often near thunderstorms. X-band data transmitter <NUM> may include these locations in the X-band data stream broadcast.

In some examples, other channels may provide similar information to that provided by X-band data transmitter <NUM>. For example, a traffic collision avoidance system (TCAS) may provide a pilot information on the location of nearby aircraft in the form of range and bearing to the aircraft. A system including X-band data transmitter <NUM> in accordance with the techniques of this disclosure, such as system <NUM>, may provide advantages for an airport, similar to airport <NUM> described in <FIG>. System <NUM> may provide redundant information a pilot may use to cross check other sources of information. System <NUM> also may offload some data communication from other channels which may free those channels for other uses, or speed up the data flow.

<FIG> is a conceptual and block diagram illustrating an example airborne weather radar system capable of receiving X-band radio data communication in accordance with one or more techniques of this disclosure. The weather radar system of <FIG> is a more detailed view of weather radars, such as weather radar systems 40A and 40B described in <FIG>. In the context of this disclosure, the term airborne in airborne weather radar system is intended to refer to a weather radar system capable of operating onboard an airplane while the airplane is airborne. It should be understood, however, that not all aspects of the weather radar functionality described in this disclosure will be performed only while an airplane is airborne. In fact, it is explicitly contemplated that certain functionality attributed to weather radar in this disclosure may be performed while an airplane is at an airport and not airborne.

The airborne weather radar system of <FIG> may include weather radar electronics <NUM>, weather radar antenna <NUM>, display unit <NUM> and auditory unit <NUM>. Weather radar electronics <NUM> includes radar transmission circuits, radar receiver circuits, signal processing circuits and may include one or more processors and computer readable media. The computer readable media may include firmware/software that the one or more processors execute to perform functions of the weather radar system. The computer readable media may include instructions executed by the processors and other circuits to include an X-band radio capability. Weather radar electronics <NUM> receives the X-band data signal from weather radar antenna <NUM>, downconverts and decodes the X-band data signal to extract the data stream and converts the data stream into an alert signal. Weather radar electronics <NUM> outputs the alert signal to display unit <NUM>.

Weather radar antenna <NUM> may include a parabolic antenna, a slotted matrix antenna or similar antenna suitable for use with a weather radar. Weather radar antenna <NUM> may be mounted on a gimbaled, motorized platform capable of aiming weather radar antenna <NUM> as needed. In the example of a slotted array antenna, weather radar antenna <NUM> also include electronic beam steering. Weather radar antenna <NUM> is configured to transmit and receive radar signals and receive the X-band radio data transmissions broadcast by X-band data transmitter <NUM>. In one example, the airborne weather radar system may insert a few listen only pulses dedicated to decode the incoming X-band data streams from airport. In other words, the weather radar need not switch to a special data receiving mode and may still perform weather radar functions while receiving the X-band data stream. Weather radar antenna <NUM> sends the received X-band radio data transmissions to airborne weather radar electronics <NUM> for decoding and processing.

Display unit <NUM> is operatively coupled to airborne weather radar electronics <NUM>. In some examples display unit <NUM> may be dedicated display that is integrated in the same unit as weather radar electronics <NUM>. In other examples display unit <NUM> may be a MFD or other display separate from weather radar electronics <NUM>, such as a tablet computer. Display unit <NUM> receives the alert signal from the display output of weather radar electronics <NUM> and presents a representation of the alert signal. In some examples the representation of the alert signal may include text such as "Wind <NUM> at <NUM> knots. " In other examples the representation of the alert signal may include a graphical overlay on a geographic diagram that shows the location of potential wind shear hazards and bird strike hazards. Still other examples may include a combination such as the geographic position of a nearby aircraft along with text depicting the aircraft's ID and altitude
Auditory unit <NUM> may be a stand-alone unit that may convert an alert signal and present the alert signal to the pilot as an auditory message. In other examples, auditory unit <NUM> may be a component of a larger system, such as a flight management system. Auditory unit <NUM> may deliver a representation of the alert signal as an auditory message. The alert signals sent to auditory unit <NUM> may include those that are in a format compatible with an auditory message. For example, airborne weather radar electronics <NUM> may receive and decode a datastream indicating that runway <NUM> has an animal obstructing the runway and output an alert signal. The alert signal may go to display unit <NUM> for display. Auditory unit <NUM> may also receive the alert signal and may present an auditory message through an auditory output, such as speakers or headphones. The auditory message in this example may be, "warning, runway <NUM> obstructed. " In some aircraft, auditory unit <NUM> may present the pilot with additional information received through the X-band radio.

In the example of <FIG>, display unit <NUM> may include controls for the pilot to set what information the display unit presents and to filter out information the pilot may not want to display. Controls may be in the form of knobs, dials, touchscreen or similar controls. For example, a pilot may choose not to display weather information from an airport's AWOS to avoid cluttering the screen on the display unit. The pilot may choose instead to receive the weather information over voice channel from ATIS. However, the pilot may choose to display possible wind shear area information.

<FIG> is a is a conceptual and block diagram illustrating an example airborne X-band radio receiver capable of receiving X-band radio data communication in accordance with one or more techniques of this disclosure. The X-band radio receiver of <FIG> is equivalent to the simple included in aircraft <NUM> as described in <FIG>.

The example airborne X-band radio receiver of <FIG> may include X-band receiver electronics unit <NUM>, omnidirectional antenna <NUM> and display unit <NUM>. Example X-band receiver electronics unit <NUM> includes radio receiver circuits, signal processing circuits and may include one or more processors and computer readable media. The computer readable media may include firmware/software that the one or more processors execute to perform functions of the X-band radio capability. X-band receiver electronics unit <NUM> receives the X-band data signal from omnidirectional antenna <NUM>, downconverts and decodes the data signal to extract the data stream and converts the data stream into an alert signal. X-band receiver electronics unit <NUM> outputs the alert signal to display unit <NUM>. Though not shown in <FIG>, X-band receiver electronics unit <NUM> may output the alert signal to an auditory alert system, as described above.

Omnidirectional antenna <NUM> may be integrated as part of the airborne X-band radio receiver, or may be mounted inside or external to an aircraft, such as aircraft <NUM>. Omnidirectional antenna <NUM> conducts received X-band radio data transmitted by X-band data transmitter <NUM> to x-band receiver electronics unit <NUM> for decoding and processing.

Display unit <NUM> is operatively coupled to X-band receiver electronics unit <NUM>. In some examples display unit <NUM> may be dedicated display integrated in the same unit as X-band receiver electronics unit <NUM>. In other examples, display unit <NUM> may be a MFD or other display separate from X-band receiver electronics unit <NUM>. Display unit <NUM> receives the alert signal from the display output of X-band receiver electronics unit <NUM> and presents a representation of the alert signal to the pilot. As described above for display unit <NUM> in <FIG>, the representation of the alert signal may include text, graphics or a combination such as the geographic position of a nearby aircraft along with text depicting the aircraft's ID and altitude. As with <FIG> above, display unit <NUM> may include controls for the pilot to set what information the display unit presents and to filter out information the pilot may not want to display.

<FIG> is a flow chart illustrating operation of an X-band data communication system in accordance with an embodiment of the invention. The flow chart of <FIG> will be described in terms of <FIG>.

An X-band data transmitter, such as X-band data transmitter <NUM> shown in <FIG> retrieves information from one or more airport detection systems (<NUM>). Airport detection systems may include ATC radar <NUM>, avian detection system <NUM> or some other detection system. The X-band data transmitter may receive this information via a wired, wireless or some other form of data communication system that connects the airport detection systems to the X-band data transmitter.

X-band data transmitter converts the information from the airport detection system into a data stream (<NUM>) that is compatible with the software/firmware data decoder loaded in a weather radar onboard an aircraft, as described above in <FIG>. Each airport detection system may output its data in a format particular to the detection system, such as Network Common Data Format (NetCDF), which may be converted so the data decoder within the weather radar system can properly interpret the data stream.

In the embodiment of the invention of <FIG> , X-band data upconverter <NUM> modulates the data stream onto a baseband carrier signal, then up-convert the baseband carrier through one or more stages of carrier multiplication and associated filtering until the modulated carrier signal reaches X-band frequency (<NUM>). The X-band modulated carrier, also referred to as X-band data, goes to low power X-band transmitter <NUM>.

Low power X-band transmitter <NUM> filters, amplifies and transmits the X-band carrier signal to omnidirectional antenna <NUM> for further broadcast (<NUM>) to aircraft in the vicinity of the airport, as described above in <FIG>. The X-band carrier signal includes the data stream with information from the one or more airport detection systems. As discussed above, the functional blocks depicted in the example of <FIG> are just one possible arrangement of the functions of X-band data transmitter <NUM>. Other examples of X-band data transmitter <NUM> may include more, fewer or a different arrangement of functional blocks.

Once broadcast, an aircraft such as aircraft <NUM> may receive the data stream transmitted from X-band data transmitter <NUM> (<NUM>). Any aircraft within receiving distance of X-band data transmitter <NUM> would be able to receive the data stream. In other words, an aircraft within approximately ten nautical miles of X-band data transmitter <NUM> may take advantage of the techniques of this disclosure. An aircraft with an X-band weather radar modified according to the techniques of this disclosure may downconvert the X-band carrier signal that includes the data stream and decode the data stream to extract the information from the airport detection systems. Unlike more complex communication systems that may include scheduling units for data fusion, a weather radar that also functions as an X-band radio receiver may include firmware/software to provide the X-band radio receiver functionality. Similarly, an aircraft without a weather radar, such as aircraft <NUM>, may include a simple X-band radio receiver unit that may also downconvert and decode the X-band carrier signal. Receiving information from airport detection systems via X-band radio receiver may free up bandwidth for the more complex data fusion communication systems to operate faster and more efficiently.

The X-band radio function of a weather radar converts the extracted information from the airport detection system into an alert signal (<NUM>). As the X-band radio receiver function uses the existing weather radar hardware, the alert signal remains compatible with the existing display unit. In some examples the display unit is integrated as part of the weather radar. In other examples, the weather radar may output the alert signal to an MFD or other display device. As described above, an X-band radio receiver on an aircraft without a weather radar may also have an integrated display unit or output the alert signal to an MFD, tablet computer or other display device as well, in some examples, deliver an auditory message.

The aircraft display unit shows a representation of the alert signal (<NUM>). As discussed above, the representation may be text, graphical or some combination of text and graphics. A pilot may select which information to show on the display unit by manipulating controls either on the display unit, or some other location, as described above. A pilot may choose to display information from airport detection systems to improve the pilot's situational awareness. In some examples a pilot may choose to duplicate information already provided by systems on board the aircraft as a cross-check and correlation. For example, an aircraft with a PWS system may still choose to display information from a ground based PWS, such as PWS <NUM>. Showing PWS information from both systems may give the pilot confidence to keep the aircraft away from any potential wind shear hazards. In other examples a pilot may choose to display information not available on board the aircraft. For example, a ground based avian detection system, such as avian detection system <NUM>, may provide information on potential bird strike danger. Receiving bird strike danger information via an X-band radio receiver may have the advantage of making more bandwidth available on voice communication channels or other data link channels.

In one or more examples, the functions described by this disclosure may be implemented in hardware, software, firmware, or any combination thereof. For example, the various components of <FIG>, such as airborne weather radar electronics <NUM>, X-band receiver electronics unit <NUM> and data conversion unit <NUM>, may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over, as one or more instructions or code, a computer-readable medium and executed by a hardware-based processing unit.

The term X-band, as used in this disclosure, generally refers to a segment of the microwave radio region of the electromagnetic spectrum that may be used for radar, including weather radar. In radar technology, the frequency range of X-band is specified by the Institute of Electrical and Electronics Engineers (IEEE) to be <NUM> to <NUM>. X-band weather radar may, for example, have a wavelength of <NUM> to <NUM> centimeters.

By way of example, and not limitation, such computer-readable storage media, which may be included in airborne weather radar electronics <NUM>, X-band receiver electronics unit <NUM> or X-band data transmitter <NUM>, can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage, or other magnetic storage devices, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.

Instructions may be executed by one or more processors, such as one or more DSPs, general purpose microprocessors, ASICs, FPGAs, or other equivalent integrated or discrete logic circuitry.

Claim 1:
A method comprising:
transmitting and receiving, by a weather radar antenna (<NUM>) of a weather radar system (40A, 40B) of an aircraft (<NUM>, <NUM>), radar signals;
receiving (<NUM>), by a data communication interface of an X-band data transmitter (<NUM>) of an airport (<NUM>), first information from a first airport detection system (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) and second information from a second information detection system (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), the first information and the second information each respectively comprising a different one of lightning coordinates, airborne aircraft location coordinates, aircraft taxi location coordinates, bird flock location coordinates, wind shear area coordinates and ground vehicle location coordinates;
converting (<NUM>), by an X-band data conversion unit (<NUM>, <NUM>) of the X-band data transmitter (<NUM>), the first information and the second information into global coordinates on a digital data stream; and modulating (<NUM>), by the X-band data conversion unit (<NUM>, <NUM>), an X-band carrier signal (<NUM>) to load the digital data stream into the X-band carrier signal; or, alternatively,
converting (<NUM>), by a data conversion unit (<NUM>) of the X-band data transmitter (<NUM>), the first information and the second information into global coordinates on a digital data stream; and loading the digital data stream into an X-band carrier signal by modulating (<NUM>), by an X-band data upconverter (<NUM>), the digital data stream onto a baseband carrier signal and up-converting the baseband carrier signal through at least one stage of carrier multiplication and associated filtering until the modulated carrier signal reaches X-band frequency;
broadcasting (<NUM>), from an omnidirectional antenna (<NUM>), the X-band carrier signal loaded with the digital data stream to the aircraft (<NUM>, <NUM>, <NUM>);
receiving (<NUM>), by the weather radar antenna (<NUM>) of the weather radar system (40A, 40B) of the aircraft (<NUM>, <NUM>), the X-band carrier signal (<NUM>) loaded with the digital data stream broadcast from the omni-directional antenna (<NUM>);
converting (<NUM>), by the weather radar system (40A, 40B), the digital data stream into an alert signal (<NUM>, <NUM>); and
outputting (<NUM>), to a pilot of the aircraft and by the weather radar system (40A, 40B), a representation of the alert signal (<NUM>).