Patent Description:
There are two versions of controller-pilot data link communications systems for ATC messaging used in the world today. The two version of CPDLC provide similar functionality but use different communications protocols which are not interoperable. , Future Air Navigation System <NUM>/A (FANS <NUM>/A) CPDLC is a standard controller-pilot data link communications system. FANS <NUM>/A CPDLC employs aircraft communications addressing and reporting system (ACARS) protocol to send and receive messages. The ACARS protocol originated from a Telex format and is a character oriented protocol. FANS <NUM>/A typically employs the ACARS protocol over an aviation VHF link control (AVLC or AOA) which sends and receives ACARS protocol messages, between an aircraft and ATC or AOC, on VHF data link mode <NUM> (VDL-Mode <NUM>) at a data rate of <NUM> kbps. Alternatively, FANS <NUM>/A can also employ Plain Old ACARS by sending and receiving ACARS protocol messages using a lower data rate, <NUM>. 4kbps, VHF data link. In another alternative, FANS <NUM>/A is capable of sending and receiving ACARS protocol messages, e.g. between an aircraft, and an ATC and/or AOC, over HF or SATCOM data links.

In Europe, a different system, Protected Mode - CPDLC (PM-CPDLC) is used to communicate data messages between an aircraft and an ATC. PM-CPDLC employs an Aeronautical Telecommunications Networks/OSI, or ATN/OSI, protocol to send and receive messages. PM-CPDLC messages are also sent and received using VDL-Mode <NUM>. PM-CPDLC utilizes the ATN/OSI protocol on VDL-Mode <NUM>. However, because FANS <NUM>/A CPDLC uses the ACARS protocol and PM-CPDLC uses the ATN/OSI protocol, the two systems are incompatible.

Most aircraft have avionics equipment that implements one version of CPDLC. For example, aircraft of U. operators typically have equipment that implements FANS <NUM>/A CPDLC; aircraft of European operators typically have equipment that implements the PM-CPDLC system. Thus, when an aircraft of a U. operator departs U. air space and enters European airspace, the pilots must rely on less efficient voice communications to communicate with the local air traffic control center.

Aircraft operators are either unable to upgrade avionics on some of their aircraft to support both versions of CPDLC and to permit graceful transition between CPDLC ATC messaging systems, or are reluctant to perform such an upgrade when available because of the cost. Therefore, there is a need for a less costly system that can be retrofitted to these older aircraft that would permits pilots to transition between the two versions of CPDLC systems.

<CIT> discloses systems and methods for communication using a plurality of data link standards through a common operator interface. In one embodiment, the system includes components configured to select and establish communication with an air traffic control center using one of a plurality of data link standards. The system further includes components configured to format at least one downlink page to only allow appropriate data inputs based on one or more functionalities of the data link standard, and encode one or more entered data inputs based on the selected data link standard and transmit the inputs to the air traffic control center. In a particular embodiment, the system further includes components configured to receive and display each of the decoded uplink data transmission in a text message on a corresponding uplink display page according to one or more message text conventions of the selected data link standard.

<CIT> discloses systems and methods for managing nonintegrated CPDLC systems from a first CPDLC system. A method includes monitoring a datalink router for messages from a first CPDLC application in a first one or more execution partitions, wherein the first one or more execution partitions are configured to implement a first CPDLC application and wherein messages from the first CPDLC application and a second CPDLC application in a second one or more execution partitions use the datalink router to interface with one or more radio transceivers. The method also includes when the second CPDLC application has an active current data authority (CDA) air traffic control (ATC) connection, inhibiting communication between the first CPDLC application and an ATC ground station by discarding downlink messages of the first CPDLC application from the datalink router.

The present invention provides a method according to claim <NUM> of the appended claims.

The invention further provides a program product according to claim <NUM> of the appended claims.

Understanding that the drawings depict only exemplary embodiments and are not therefore to be considered limiting in scope, the exemplary embodiments will be described with additional specificity and detail through the use of the accompanying drawings, in which:.

In accordance with common practice, the various described features are not drawn to scale but are drawn to emphasize specific features relevant to the exemplary embodiments. Reference characters denote like elements throughout figures and text.

Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding background and summary, or the following detailed description.

<FIG> illustrates one embodiment of a system <NUM> with an aircraft <NUM> including a communications protocol control application system. The system <NUM> includes the aircraft <NUM> including the communications protocol control application system, an air traffic control center (ATC) <NUM>, and an airlines operation center (AiOC) <NUM>. The aircraft <NUM> including the communications protocol control application system is coupled to the ATC <NUM> and the AiOC <NUM> respectively by a first communications link 105A and a second communications link 105B. In another embodiment, the first communications link 105A and second communications link 105B use the same communications protocol, e.g. ACARS. In a further embodiment, the first communications link 105A and the second communications link 105B use different communications protocols, e.g. respectively ATN/OSI and ACARS. In one embodiment, each of the first communications link 105A and the second communications link 105B are one or more of a HF, VHF, satellite, AeroMACs communications link and/or any communications links approved for aeronautical message communications. In another embodiment, at least one ATC message <NUM> is communicated between the aircraft <NUM> and the ATC <NUM>. In a further embodiment, at least one automatic dependent surveillance - contract (ADC-C) message <NUM> is communicated between the aircraft <NUM> and the ATC <NUM>. In yet another embodiment, at least one aeronautical operational control (AOC) messages and airline administrative control (AAC) message (AOC/AAC message) <NUM> is communicated between the aircraft <NUM> and the AiOC <NUM>.

<FIG> illustrates one embodiment of an aircraft <NUM> including a communications protocol control application system <NUM>. The aircraft <NUM> further includes a flight management system (FMS) <NUM>, a communications management system (CMS) <NUM>, a communications system <NUM>, at least one input / output device (I/O) <NUM>, at least one sensor <NUM>, and at least one control system <NUM>. In one embodiment, the flight management system <NUM> is coupled to the communications management system <NUM>, the at least one I/O <NUM>, the at least one sensor <NUM>, and the at least one control system <NUM>. In another embodiment, the flight management system <NUM> hosts applications (or application systems or sub-systems) as will be further described below.

In one embodiment, the communications management system <NUM> is coupled to the communications system <NUM> and the at least one I/O <NUM>. In another embodiment, the communications management system <NUM> hosts applications (or applications systems or sub-systems) as will be subsequently described. The communications management system <NUM> is commonly known as a communications management unit or CMU.

The communications system <NUM> includes one or more transceivers, including for HF, VHF, microwave, satellite, AeroMACs, and any other current or future voice and/or data communications, e.g. L-band Digital Aeronautical Communications System (LDACS). <FIG> illustrates one embodiment of a communications system <NUM> having a VHF transceiver 106A, a satellite communications (SatCom) transceiver 106B, and a HF transceiver 106C. In one embodiment, the VHF transceiver 106A includes a VHF data link mode <NUM> (VDL-Mode <NUM>) mode. In another embodiment, the communications system <NUM> includes the requisite antenna(s) for the one or more transceivers.

The at least one I/O <NUM> includes at least one display 108A and/or at least one input device 108B. In one embodiment, the at least one display 108A is at least one multifunction display and/or at least one touchscreen display. In another embodiment, the at least one input device 108B is at least one cursor control device and/or at least one keyboard. In a further embodiment, messages are entered and displayed with the at least one I/O <NUM>.

In one embodiment, the at least one sensor <NUM> includes at least one global navigation satellite system (GNSS), e.g. GPS, receiver, at least one pitot tube, and/or at least one barometric and/or radar altimeter. The at least one GNSS receiver can be used to determine three-dimensional location and vector velocity (and a corresponding time) of the aircraft <NUM>. The at least one pitot tube can be used to determine speed of the aircraft <NUM>. The at least one barometric and/or radar altimeter can be used to determine altitude of the aircraft <NUM>. In another embodiment, the at least one sensor <NUM> includes sensors that detect engagement and disengagement of the parking brake of the aircraft <NUM>, and the opening and closing of a door of the aircraft <NUM>. The at least one control system <NUM> includes surface controls, such as ailerons, elevators and rudders, each of their corresponding actuators, engines, and systems for controlling them, e.g. an autopilot.

The flight management system <NUM> is primarily used to provide in-flight management of the aircraft's flight plan during transit. Using information from the at least one sensor <NUM>, the flight management system <NUM> determines the aircraft's position and guides the aircraft along the flight plan. The flight management system provides such information to the crew of the aircraft through the at least one I/O 108A. Additionally, the flight management system <NUM> (through a FANS <NUM>/A application) facilitates creation, sending, receipt and display of messages using the ACARS protocol.

In one embodiment, the flight management system <NUM> comprises a FMS memory 102A coupled to a FMS processor 102B. In another embodiment, all or part of the FMS memory 102A and the FMS processor 102B may be implemented by a state machine or a field programmable gate array.

The FMS memory 102A includes a navigation system <NUM> and first datalink applications system <NUM>. The navigation system <NUM> is executed by the FMS processor <NUM>, and facilitates determination of aircraft position and implementation of the flight plan.

In one embodiment, the first datalink applications system <NUM> includes a first ATC datalink application sub-system 122A that performs CPDLC messaging and a first AOC datalink application sub-system 122B that performs AOC and/or AAC messaging. In another embodiment, the first datalink applications system <NUM> includes an ADS-C datalink application sub-system 122C that performs ADC-C messaging. In a further embodiment, the first ATC datalink application sub-system 122A and the ADS-C applications datalink sub-system 122C are part of a FANS <NUM>/A system.

In one embodiment, the first ATC datalink application sub-system 122A is configured to generate (including to encode) and decode at least one ATC message <NUM> using a first communications protocol to be sent to or received from an ATC. The first AOC datalink application sub-system 122B facilitates communications between the aircraft <NUM> and the AiOC <NUM>. In one embodiment, the first AOC datalink application sub-system 122B is configured to generate (including to encode) and decode, using a first communications protocol, at least one at least one AOC/AAC message <NUM> such as messaging between the aircraft <NUM> and the AiOC <NUM>, and notification of an aircraft's departure from gate, arrival to gate, takeoff and landing, e.g. triggered by door and parking brake sensors. In another embodiment, the first communications protocol is ACARS. In yet another embodiment, the first datalink applications system <NUM> directs decoded messages to the at least one I/<NUM><NUM> for display. In yet a further embodiment, the first datalink applications system <NUM> directs encoded messages to the communications management system <NUM> for routing and transmission to ground locations such as the ATC <NUM> and the AiOC <NUM>.

In one embodiment, ADS-C applications datalink sub-system 122C so generates and decodes at least one ADS-C message <NUM>, e.g. which periodically provides to the ATC <NUM> an aircraft identifier, <NUM>-D position, a time stamp, and an indication of navigation figure of merit or accuracy. The at least one ADS-C message <NUM> sent from the aircraft <NUM> to the ATC <NUM> may also include ground speed, air speed, heading, vertical rate, next waypoint, and meteorological information.

The communications management system (CMS) <NUM> is configured to facilitate two-way air-ground datalink communications. The communications management system <NUM> is configured to route datalink communications, e.g. ATC messages <NUM>, AOC/AAC messages <NUM>, and ADS-C messages <NUM>, between, e.g., the FMS <NUM>, CMS <NUM>, and/or other aircraft systems, and endpoints, such as the ATC <NUM> and/or AiOC <NUM>. The communications management system <NUM> routes datalink communications, such as messages, to and from one or more transceivers in the communications system <NUM> that form part of a communications link between the datalink application subsystems, in the FMS or CMS, and the ATC <NUM> and/or AiOC <NUM> on the ground. In one embodiment, the routing function is performed for two or more air-ground datalink message protocols such as ACARS, Aeronautical Telecommunications Networks (ATN)/Open Systems Interconnection (OSI), and ATN/Internet Protocol (IP). In another embodiment, the communications management system <NUM> is configured to:.

In one embodiment, the communications management system <NUM> comprises a CMS memory 104A coupled to a CMS processor 104B. In another embodiment, all or part of the CMS memory 104A and the CMS processor 104B may be implemented by a state machine or a field programmable gate array.

In one embodiment, the CMS memory 104A comprises at least one router <NUM>, e.g. for ACARS and ATN protocol messages, a second datalink applications system <NUM>, a data processing system <NUM>, and/or a communications protocol control application system <NUM>. The at least one router <NUM>, second datalink applications system <NUM>, data processing system <NUM> and/or communications protocol control application system <NUM> are executed on the CMS processor 104B.

Each of the at least one router <NUM> is configured to relay and route messages, e.g. at the frame and packet level respectively for ACARS, ATN/OSI and ATN/IP, between the FMS <NUM>, CMU <NUM> or other aircraft systems and end points, such as the ATC <NUM> and AiOC <NUM>, in communications with a transceiver in the communications system <NUM>. In one embodiment, the at least one router <NUM> includes separate routers for different protocols, such as ACARS and ATN/OSI. In another embodiment, if the ATN/ IP is used, the at least one router <NUM> would include an IP router. In a further embodiment, the relay and routing functionality of each of the at least one router <NUM> is accomplished by a routing table or policy within the corresponding router. In yet another embodiment, a single router may be used to route messages of two or more protocols.

In one embodiment, the second datalink applications system <NUM> includes a second ATC datalink application sub-system 126A that performs CPDLC messaging and a second AOC datalink application sub-system 126B that performs AOC and/or AAC messaging.

In one embodiment, the second ATC datalink application sub-system 126A is configured to generate (including to encode) and decode at least one ATC message <NUM> using a second communications protocol to be sent to or received from an ATC. In another embodiment, the second communications protocol is ATN/OSI, or alternatively ATN/Internet Protocol (IP). In a further embodiment, the second communications protocol system <NUM> is part of a protected mode CPDLC system. The data processing system <NUM> is configured to perform at least one of encryption and decryption, compression and decompression, and data verification coding or decoding and analysis as further described above.

The second AOC datalink application sub-system 122B facilitates communications between the aircraft <NUM> and the AiOC <NUM>. In one embodiment, the second AOC datalink application sub-system 126B is configured to generate (including to encode) and decode, using a first communications protocol, at least one at least one AOC/AAC message <NUM> such as messaging between the aircraft <NUM> and the AiOC <NUM>, and notification of an aircraft's departure from gate, arrival to gate, takeoff and landing, e.g. triggered by door and parking brake sensors. In another embodiment, the first communications protocol is ACARS. In yet another embodiment, the second datalink applications system <NUM> directs decoded messages to the at least one I/<NUM><NUM> for display. In yet a further embodiment, the second datalink applications system <NUM> directs encoded messages to at least one router <NUM> for routing and transmission to ground locations such as the ATC <NUM> and the AiOC <NUM>.

In one embodiment, the first ATC datalink application sub-system 122A, the second AOC datalink application sub-system 122B, and the second AOC datalink application sub-system 126B generate ATC messages <NUM>, and/or AOC/AAC messages <NUM> in a first ACARS communications protocol that is suitable for transmission between or within avionics such as the FMS <NUM> and the CMS <NUM>. Such messages are then subsequently converted to a second ACARS communications protocol within the CMS <NUM> prior to be transmitted by the communications system <NUM> to the ATC <NUM> and/or the AiOC <NUM>. Similarly, ATC messages <NUM> and/or AOC/AAC messages <NUM> received by the communications system <NUM> will be in the second ACARS communications protocol. Such messages are subsequently converted to a first ACARS communications protocol with in the CMS <NUM> prior to being routed to the first ATC datalink application sub-system 122A, the second AOC datalink application sub-system 122B, and/or the second AOC datalink application sub-system 126B in the FMS <NUM> and the CMS <NUM>.

In one embodiment, the communications protocol control application system <NUM> is configured to select a datalink applications system, and thus a corresponding CPDLC communications protocol. In another embodiment, the selection of CPDLC communications protocol corresponds to a selection of a CPDLC system.

In one embodiment, the communications protocol control application system <NUM> automatically selects a CPDLC communications protocol, e.g. a CPDLC system, e.g. FANS <NUM>/A or Protected Mode CPDLC. In another embodiment, the communications protocol control application system <NUM> has a single default CPDLC communications protocol and/or CPDLC system stored in it, which is selected when the communications protocol control application system <NUM> is activated. In a further embodiment, CPDLC communications protocols and/or systems for different geographical regions are stored, e.g. in the communications protocol control application system <NUM>. Then, by determining the location of the aircraft <NUM>, e.g. from the flight management system <NUM>, the communications protocol control application system <NUM> can determine which CPDLC system and protocol to use. In yet another embodiment, a user, e.g. a pilot, can select with the at least one I/Os <NUM> which CPDLC communications protocol and/or system to use. In yet a further embodiment, at or before the commencement of travel of the aircraft <NUM>, the communications protocol control application system <NUM> prompts the user, with the at least one I/Os <NUM>, to select an initial CPDLC communications protocol and/or system to use. Again, the user would select such a mode with the at least one I/Os <NUM>.

<FIG> illustrates one embodiment of a method <NUM> for sending and receiving air traffic control messages using different protocols. To the extent that the embodiment of method <NUM> shown in <FIG> is described herein as being implemented in the systems shown in <FIG>, it is to be understood that other embodiments can be implemented in other ways. The blocks of the flow diagrams have been arranged in a generally sequential manner for ease of explanation; however, it is to be understood that this arrangement is merely exemplary, and it should be recognized that the processing associated with the methods (and the blocks shown in the Figure) can occur in a different order (for example, where at least some of the processing associated with the blocks is performed in parallel and/or in an event-driven manner).

In one embodiment, in block <NUM>, receive a selection of an initial ATC message communications protocol and/or CPDLC system. In another embodiment, selection of a first communications protocol corresponds to selection of a first CPDLC system; selection of a second communications protocol corresponds to selection of a second CPDLC system. Thus, for example, selection of the ACARS protocol corresponds to a selection of the first datalink applications system <NUM>, and e.g. the FANS <NUM>/A system. ACARS messages would be encoded and decoded by the first ATC datalink application sub-system 122A. Further, for example, selection of the ATN/OSI protocol corresponds to a selection of the second datalink applications system <NUM>, and e.g. the PM-CPDLC system. ATN/OSI messages would be encoded and decoded by the second ATC datalink application sub-system <NUM>.

In one embodiment, a user, e.g. a pilot, selects the initial ATC message communications protocol and/or CPDLC system, for example with the at least one I/Os <NUM>. In another, embodiment, a default initial ATC message communications protocol and/or CPDLC system is selected, e.g. depending on the location (for example Europe versus the U. ) of the aircraft <NUM> obtained from a GNSS receiver that is part of the at least one sensor <NUM>. In a further embodiment, the default initial ATC message communications protocol and/or CPDLC system is pre-determined by, and stored in, e.g. the communications protocol control application system <NUM>.

In one embodiment, receipt of a selection of one of two or more communications protocols and/or CPDLC systems is possible. However, the selection of one of two communications protocols will be exemplified. In another embodiment, a first communications protocol is ACARS. In a further embodiment, a second communications protocol is ATN/OSI. In yet another embodiment, the second or third communications protocol is ATN/IP.

In block <NUM> determine if the second communications protocol has been selected. In one embodiment, determining if a second communications protocol has been selected includes determining if a CPDLC system using the second communications protocol has been selected. If the second communications protocol has not been selected, then in one embodiment, then proceed to block <NUM>. If the second communications protocol has been selected, then in one embodiment, in block <NUM>, enable the ability to send and receive messages in the second communications protocol, e.g. by enabling the second datalink applications system <NUM> including the second ATC datalink application sub-system 126A.

In block <NUM>, trap any received and to be sent ATC messages <NUM> encoded with the first communications protocol, e.g. any FANS <NUM>/A ATC messages. In one embodiment, received ATC messages <NUM>, encoded in the first communications protocol, are received from an ATC <NUM> and delivered to the communications management system <NUM>. In another embodiment, ATC messages <NUM>, encoded in the first communications protocol, originate in the flight management system <NUM> (e.g. the first ATC datalink application sub-system 122A) and are transferred to the communications management system <NUM> to be relayed onwards. In a further embodiment, the communications protocol control application system <NUM> traps such ATC messages <NUM> which are encoded with the first communications protocol. Trapping means that the ATC messages <NUM> using the first communications protocol are not delivered to their intended destination, e.g. a component of the aircraft <NUM> or the ATC which are for example parts of FANS <NUM>/A systems. In yet another embodiment, the trapped messages are acknowledged as being received, e.g. by the communications protocol control application system <NUM> to the message source such as the FMS <NUM>, ATC <NUM>, or AiOC <NUM>; this prevents those systems from consuming bandwidth by continually repeating the same message and awaiting a confirmation receipt.

In one embodiment, if an ATC message <NUM> is trapped, a datalink is disconnected between the first ATC datalink application sub-system 122A employing the first communications protocol, e.g. the FANS <NUM>/A system, in the vehicle <NUM>, and a communications system, e.g. a FANS <NUM>/A system, in an ATC <NUM> employing the first communications protocol. In a further embodiment, the datalink is disconnected by sending at least one disconnect message, e.g. from the communications protocol control application system <NUM> to the first ATC datalink application sub-system 122A and/or the communications system in the ATC <NUM>.

In block <NUM>, send and/or receive at least one ATC message <NUM> using the second communications protocol. Then, proceed to block <NUM>.

In one embodiment, block <NUM>, disable the ability to send and receive messages in the second communications protocol, e.g. by disabling the second datalink applications system <NUM> including the second ATC datalink application sub-system 126A. In block <NUM>, send and/or receive at least one ATC message <NUM> using the first communications protocol. Then proceed to block <NUM>.

In one embodiment, in block <NUM>, send and/or receive at least one AOC/AAC message <NUM>, e.g. respectively between the AOC datalink application sub-system of the selected datalink applications system and the AiOC <NUM>. Thus, if the first datalink applications system, e.g. the FANS <NUM>/A system, has been selected, the at least one AOC/AAC message <NUM> is sent and/or received using the first AOC datalink application sub-system 122B. Alternatively, if the second datalink applications system, e.g. the PM-CPDLC system, has been selected, the at least one AOC/AAC message <NUM> is sent and/or received using the second AOC datalink application sub-system 126B. In another embodiment, the at least AOC/AAC message <NUM> is sent and/or received using the first communications protocol, e.g. the ACARS protocol.

In one embodiment, in block <NUM>, send and/or receive at least one ADS-C message, e.g. respectively from the ADS-C datalink application sub-system 122C and to the AiOC <NUM>. In another embodiment, the ADS-C messages 115are implemented in the first communications protocol, second communications protocol, or any other protocol. In a further embodiment, in block <NUM>, receive another selection of another ATC message communications protocol and/or CPDLC system.

Claim 1:
A method, comprising:
receiving, from a user or from a communications management unit (<NUM>), a selection of at least one of: an initial air traffic control, ATC, message communications protocol and an initial controller-pilot data link communications, CPDLC, system, wherein each CPDLC system is configured to use either a first communications protocol or a second communications protocol (<NUM>);
determining if the second communications protocol was selected (<NUM>);
determining that the second communications protocol was selected, then trapping at least one of a received ATC message in the first communications protocol, and an ATC message in the first communications protocol configured to be sent (<NUM>), thereby preventing the ATC message from reaching its intended destination , wherein such preventing is performed without disconnecting a datalink using the first communications protocol; and
at least one of sending an ATC message in the selected ATC message communications protocol and receiving an ATC message in the selected ATC message communications protocol (<NUM>, <NUM>).