# US 2018/0321370 A1 · Method for controlling message transmission power implemented by a system for preventing collisions of aircraft during flight > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0321370 A1 - Document ID: US20180321370A1 - Status: Published application - Kind: A1 - Application number: 15/774,874 - Filed: 2016-11-08 - Published: 2018-11-08 - Earliest claimed: 2015-11-13 - Applicants: Airbus Operations SAS - Inventors: Jean-Luc ROBIN - Web page: https://patentgrep.com/patent/US20180321370A1 ## CPC - G01S 13/781: {Secondary Surveillance Radar [SSR] in general} - G01S 7/023: {Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques (auxiliary means for detecting or identifying radar signals or the like G01S7/021; means for anti-jamming G01S7/36)} - G01S 13/782: {using multimoding or selective addressing} - G01S 13/933: of aircraft or spacecraft - G08G 5/21: located onboard the aircraft - G08G 5/25: Transmission of traffic-related information between aircraft - G08G 5/723: {from the aircraft} - G08G 5/80: Anti-collision systems - H04B 7/18506: {Communications with or from aircraft, i.e. aeronautical mobile service} - G01S 7/4013: {involving adjustment of the transmitted power} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93}) - H04B: TRANSMISSION ## Abstract A method and system for controlling message transmission power implemented by a system for preventing collisions of aircraft during flight, the prevention system comprising an anti-collision device and a transponder with which each plane is equipped. There is a step for measuring at least the quality value of a quantity representative of the quality at which radio-frequency signals carrying response messages transmitted by a transponder of an intruding aircraft are received, and a step for controlling the power of transmission of the radio-frequency signals carrying the response messages depending o the quality value or values measured in this way. ## Claims ### Claim at position 1 1-16. (canceled) ### Claim 17 A method of controlling a transmission power of messages used by a traffic alert and collision avoidance system, said system including an anti-collision apparatus and a transponder equipping each aircraft, said method including the following steps carried out by said anti-collision apparatus of a first aircraft: transmitting request messages in the form of radiofrequency signals carrying said messages, and receiving radiofrequency signals carrying response messages transmitted by said transponder in response to said request messages, said method further including the following steps carried out by said transponder of a second aircraft: receiving the radiofrequency signals carrying request messages transmitted by said anti-collision apparatus, and transmitting the radiofrequency signals carrying response messages in response to request messages, said method further including the following steps carried out by said anti-collision apparatus of said first aircraft: measuring at least a value, termed a quality value, of a magnitude representing a quality of reception of the radiofrequency signals carrying response messages transmitted by said transponder and encapsulating data representing said quality value or values in said request message to be transmitted by said anti-collision apparatus, said method further including the following steps carried out by said transponder of said second aircraft: controlling the transmission power of the radiofrequency signals carrying said response messages as a function of the quality value or values encapsulated in the request messages transmitted by said anti-collision apparatus of said first aircraft. ### Claim 18 (depends on 17) The power control method according to claim 17, further including the following steps carried out by said transponder, measuring at least a value, termed a quality value, of a magnitude representing a quality of reception of the radiofrequency signals carrying request messages transmitted by an anti-collision apparatus, and encapsulating data representing said measured quality value or values in a response message, and further including the following steps carried out by said anti-collision apparatus, setting the transmission power of the radiofrequency signals carrying said request messages as a function of the quality value or values encapsulated in the response messages transmitted by said transponder. ### Claim 19 (depends on 18) The power control method according to claim 18, wherein the quality value of the radiofrequency signal measured in the step of measuring the quality value of the transponder signals or measuring the quality value of the anti-collision apparatus signals is the value of at least one of the following characteristics: a reception power of the radiofrequency signals carrying a response message received from the transponder, a signal-to-noise ratio of the radiofrequency signal carrying the response message received from the transponder, a bit error rate of the radiofrequency signal carrying the response message received from the transponder. ### Claim 20 (depends on 17) The power control method according to claim 17, wherein said control step includes: comparing the or each quality value to a threshold value, increasing the transmission power of a next response message to be transmitted if the quality represented by the or each quality value is less than the quality represented by said threshold value, and reducing the transmission power of a next request message to be transmitted if the quality represented by the or each quality value is greater than the quality of that threshold value. ### Claim 21 (depends on 17) The power control method according to claim 17, including a step of setting the transmission power to a value greater than a current value if the step of receiving the radiofrequency signals carrying request messages transmitted by said anti-collision apparatus does not receive any request message from an anti-collision apparatus during a predetermined time. ### Claim 22 (depends on 17) The power control method according to claim 17, including a step of dynamic adjustment of the threshold value as a function of the value taken by at least one aeronautical parameter. ### Claim 23 (depends on 22) The power control method according to claim 22, wherein said adjustment step dynamically adjusts said threshold value as a function of the nature of the request messages received. ### Claim 24 (depends on 22) The power control method according to claim 22, wherein said adjustment step dynamically adjusts said threshold value upward if a traffic advisory or a resolution advisory has been transmitted by an anti-collision apparatus. ### Claim 25 (depends on 22) The power control method according to claim 22, wherein said adjustment step dynamically adjusts said threshold value upward if the altitude of the aircraft decreases. ### Claim 26 (depends on 17) The power control method according to claim 17, including a step of setting the transmission power of a next response message to be transmitted to a predetermined maximum power, said control step being carried out if the received request message does not contain data relating to the quality value of the radiofrequency signals previously received by said anti-collision apparatus. ### Claim 27 (depends on 17) The power control method according to claim 17, further including a step of determining aeronautical data and a step of modifying the threshold value as a function of the values of said aeronautical data. ### Claim 28 A method of controlling the transmission power of messages implemented by a transponder of a traffic alert and collision avoidance system of an aircraft to prevent the collision of said aircraft in flight with another aircraft, said method including the following steps: receiving radiofrequency signals carrying a request message transmitted by an anti-collision apparatus of said other aircraft, transmitting to said anti-collision apparatus a response message in the form of radiofrequency signals carrying said message, wherein said method includes a control step of setting the transmission power of the radiofrequency signals carrying said response messages as a function of a quality value or values encapsulated in the request message received from said anti-collision apparatus. ### Claim 29 (depends on 28) The power control method according to claim 28, wherein said control step includes: comparing the or each quality value to a threshold value, increasing the transmission power of a next response message to be transmitted if a quality represented by the or each quality value is less than the quality represented by said threshold value, and reducing the transmission power of a next request message to be transmitted if the quality represented by the or each quality value is greater than the quality of that threshold value. ### Claim 30 (depends on 28) The power control method according to claim 28, including a step of setting the transmission power to a value greater than a current value if the step of receiving the radiofrequency signals carrying request messages transmitted by said anti-collision apparatus does not receive any request message from an anti-collision apparatus during a predetermined time. ### Claim 31 (depends on 28) The power control method according to claim 28, including a step of dynamic adjustment of the threshold value as a function of the value taken by at least one aeronautical parameter. ### Claim 32 (depends on 28) The power control method according to claim 28, including a step of setting the transmission power of the next response message to be transmitted to a predetermined maximum power, said control step being carried out if the received request message does not contain data relating to the quality value of the radiofrequency signals previously received by said anti-collision apparatus. ### Claim 33 A power control method implemented by an anti-collision apparatus of a traffic alert and collision avoidance system of an aircraft, comprising: generating a request message, transmitting in the form of radiofrequency signals the request message resulting from the generating step, receiving the radiofrequency signals carrying a response message transmitted by a transponder of another aircraft in response to said request message, and measuring a quality of the radiofrequency signals received from said transponder and carrying the response message, data representing the quality value or values measured being encapsulated in a new request message generated in a new step of generation of a request message. ### Claim 34 A traffic alert and collision avoidance system for preventing collision of a first aircraft and a second aircraft, of the type including an anti-collision apparatus equipping said first aircraft and a transponder equipping said second aircraft, said anti-collision apparatus including a transmission system for transmitting request messages in the form of radiofrequency signals carrying said messages, and a receiver for receiving radiofrequency signals carrying response messages transmitted by said transponder in response to said request messages, said transponder including a reception system for receiving radiofrequency signals carrying request messages transmitted by an anti-collision apparatus, and a transmitter for transmitting radiofrequency signals carrying response messages in response to request messages, wherein said transponder includes a measurement unit for measuring at least a value, termed a quality value, of a magnitude representing a quality of reception by the reception system of the radiofrequency signals carrying request messages transmitted by an anti-collision apparatus and an encapsulation unit for encapsulating said quality value or values in said response message, and wherein said anti-collision apparatus includes a control unit for setting the transmission power of the transmission system as a function of the quality value or values encapsulated in the response messages transmitted by said transponder. ### Claim 35 (depends on 34) The anti-collision apparatus of the system according to claim 34 for preventing collision of a first aircraft and a second aircraft, said anti-collision apparatus including a transmission system for transmitting to a transponder of an intruder aircraft request messages in the form of radiofrequency signals carrying said messages and a receiver for receiving radiofrequency signals carrying response messages transmitted by said transponder in response to said request messages, further including a control unit for setting the transmission power of the transmission system as a function of a quality value or values encapsulated in the response messages transmitted by said transponder. ### Claim 36 (depends on 35) The transponder of the system according to claim 35 for preventing a collision of a first aircraft and a second aircraft, said transponder including a reception system for receiving radiofrequency signals carrying request messages transmitted by an anti-collision apparatus and a transmitter for transmitting radiofrequency signals carrying response messages in response to request messages, further including a measurement unit for measuring at least a value, termed a quality value, of a magnitude representing a quality of reception by the reception system of the radiofrequency signals carrying request messages transmitted by an anti-collision apparatus and an encapsulation unit for encapsulating said quality value or values in said response message.