Abstract: The secondary radar includes an antenna having a radiation pattern forming a sum channel, designated SUM, a radiation pattern forming a difference channel, designated DIFF, and a pattern forming a control channel, designated CONT, the targets are located by implementing the following steps: detecting ADS-B squitters received via the CONT channel, via the SUM channel and via the DIFF channel; measuring at least the power of the squitters and their azimuth with respect to the radar; the location of a target transmitting ADS-B squitters being computed by exploiting at least the detection of one ADS-B squitter, in light of the latitudinal and longitudinal position of the radar and of the azimuthal measurement with respect to the radar, the position cell, designated the CPR cell, coded in the squitter being selected via the azimuthal measurement.

Abstract: The radar includes an antenna having a radiation pattern forming a sum channel, SUM, a radiation pattern forming a difference channel, DIFF, and a pattern forming a control channel, CONT, a first transmission and reception chain being associated with the SUM channel and a second transmission and reception chain being associated with the CONT channel, a reception channel being associated with the DIFF channel. Each of the transmission and reception chains is able to transmit and to receive simultaneously, the transmission chain comprising a filtering operation that filters signals transmitted at 1090 MHz and the reception chain comprising a filtering operation that filter signals transmitted at 1030 MHz, in such a way that the chains operate independently of one another.

Abstract: A density of Mode S interrogations and responses in the environment covered by a secondary radar is characterized according to the following steps: a first step wherein the radar: detects and locates Mode S targets by way of their synchronous responses to the interrogations emitted by the radar; detects asynchronous responses emitted by the Mode S targets, and not elicited by the radar; for each target, associates its asynchronous responses with its synchronous response to the radar; a second step wherein the radar: based on the association, determines the response rate of each target by counting the number of synchronous and asynchronous responses received from the target per given time period; with the environment being divided into elementary space cells, determines the response rate per cell by counting the number of synchronous and asynchronous responses received by each target in each cell, the rate characterizing the density of Mode S interrogations per cell.

Abstract: A method for detecting conflicts in the II/SI identification code of radars nearby a secondary mode-S radar, includes at least: a first step wherein the radar detects unsolicited unsynchronized replies, i.e. fruits, in a region of extended radar coverage; a second step wherein the radar detects a conflict in II/SI code by analyzing geographic regions of radar coverage common to the radar and to at least one nearby radar, a conflict being detected if the radar: detects, in the region of extended coverage, the presence of fruits that have as source the nearby radar; observes the absence of fruits caused by the nearby radar in that region of radar coverage of the radar which does not overlap with the region of radar coverage of the nearby radar; the region of overlap between the radar coverage of the radar and the radar coverage of the nearby radar forming a region of conflict in II/SI code.

Abstract: A radar includes an antenna having a radiating pattern forming a sum channel, a radiating pattern forming a difference channel and a pattern forming a control channel, and generates at least interrogation messages on the sum channel and interrogation messages on the control channel; transmits messages via the sum channel and via the control channel respectively, and receives and processes signals received via the sum, difference, and control channels, configured for detecting replies of targets on the signals received via the sum and difference channels and carrying out monopulse processing and RSLS processing on the replies.

Abstract: Each pattern being associated with a reception channel, over a given time period, the unsolicited asynchronous replies, of long ADS-B squitters type, transmitted by targets present in the airborne environment of the radar, are detected, each of the squitters containing position information on the target which transmits it; for each detection, the long ADS-B squitter is decoded to check that the detected target is located in accordance with the position information contained in the squitter, the non-conforming detections being rejected; for each detection retained, the time of the detection, the value of the azimuth of the main beam of the antenna and the received power value on each of the reception channels is associated with the detection, the position information contained in the squitters giving the elevation segment wherein the detection is situated; the values obtained over the period being stored, the measured patterns being sampled, by elevation segment, from the stored values.

Abstract: The secondary radar includes an antenna having a radiation pattern forming a sum channel, designated SUM, a radiation pattern forming a difference channel, designated DIFF, and a pattern forming a control channel, designated CONT, the targets are located by implementing the following steps: detecting ADS-B squitters received via the CONT channel, via the SUM channel and via the DIFF channel; measuring at least the power of the squitters and their azimuth with respect to the radar; the location of a target transmitting ADS-B squitters being computed by exploiting at least the detection of one ADS-B squitter, in light of the latitudinal and longitudinal position of the radar and of the azimuthal measurement with respect to the radar, the position cell, designated the CPR cell, coded in the squitter being selected via the azimuthal measurement.

Abstract: An ADS-B spoofer being an false ADS-B squitter, an ADS-B squitter being an aircraft position information signal transmitted to secondary radars, the ADS-B squitters being detected over time at different bearings of the antenna in rotation of the radar, the method comprises, for each secondary radar, at least the following steps: a first step of detection of an ADS-B spoofer; a second step of location of the position in azimuth of the ADS-B spoofer generator, the second step comprising the following operations: measurement of the azimuth of the antenna of the secondary radar and of the received powers on the sum, difference and control patterns of the antenna upon the detection of an ADS-B squitter; generation and storage of at least one assumption of azimuth of the spoofer for each ADS-B squitter detected, the assumption being equal to the sum of the azimuth of the antenna and of the estimated bearing of the spoofer, the estimated bearing being characterized by the ratio of the received power on the sum patte

Abstract: The radar includes an antenna having a radiation pattern forming a sum channel, SUM, a radiation pattern forming a difference channel, DIFF, and a pattern forming a control channel, CONT, a first transmission and reception chain being associated with the SUM channel and a second transmission and reception chain being associated with the CONT channel, a reception channel being associated with the DIFF channel. Each of the transmission and reception chains is able to transmit and to receive simultaneously, the transmission chain comprising a filtering operation that filters signals transmitted at 1090 MHz and the reception chain comprising a filtering operation that filter signals transmitted at 1030 MHz, in such a way that the chains operate independently of one another.

Abstract: A density of Mode S interrogations and responses in the environment covered by a secondary radar is characterized according to the following steps: a first step wherein the radar: detects and locates Mode S targets by way of their synchronous responses to the interrogations emitted by the radar; detects asynchronous responses emitted by the Mode S targets, and not elicited by the radar; for each target, associates its asynchronous responses with its synchronous response to the radar; a second step wherein the radar: based on the association, determines the response rate of each target by counting the number of synchronous and asynchronous responses received from the target per given time period; with the environment being divided into elementary space cells, determines the response rate per cell by counting the number of synchronous and asynchronous responses received by each target in each cell, the rate characterizing the density of Mode S interrogations per cell.

Abstract: An each pattern is provided a reception pathway, the method uses the synchronous replies and the asynchronous replies, unsolicited of Fruit type, transmitted by targets present in the aerial environment of the radar and detected over a given number of antenna revolutions. At each detection of a reply the value of its off-aim in bearing and the value of relative power received on each of the pathways are calculated as is its elevation by extrapolation with the synchronous detections close to the same target and associated with the detection. The values obtained over the given number of revolutions are stored, the measured patterns being sampled on the basis of the stored values.

Abstract: A test method in operational phase includes three distinct steps, a first step using the replies of the transponder to the interrogations in the Mode S transmitted in operational mode by the secondary radar to perform the measurement of the power of the transponder, and the measurement of the average rate of reply to the interrogations in Mode S transmitted by the radar intended for it; a second step which performs the measurement of the sensitivity of the transponder and a third step which carries out the test of its maximum rate of reply. The second step and the third step are carried out by modifying the operating parameters of the radar so that the additional interrogations required for the measurement can be performed, during the time interval following the last operational interrogation during which the aircraft remains located within the main Sum channel lobe of the antenna of the radar.

Abstract: A method for detecting conflicts in the II/SI identification code of radars nearby a secondary mode-S radar, includes at least: a first step wherein the radar detects unsolicited unsynchronized replies, i.e. fruits, in a region of extended radar coverage; a second step wherein the radar detects a conflict in II/SI code by analyzing geographic regions of radar coverage common to the radar and to at least one nearby radar, a conflict being detected if the radar: detects, in the region of extended coverage, the presence of fruits that have as source the nearby radar; observes the absence of fruits caused by the nearby radar in that region of radar coverage of the radar which does not overlap with the region of radar coverage of the nearby radar; the region of overlap between the radar coverage of the radar and the radar coverage of the nearby radar forming a region of conflict in II/SI code.

Abstract: A radar includes an antenna having a radiating pattern forming a sum channel, a radiating pattern forming a difference channel and a pattern forming a control channel, and generates at least interrogation messages on the sum channel and interrogation messages on the control channel; transmits messages via the sum channel and via the control channel respectively, and receives and processes signals received via the sum, difference, and control channels, configured for detecting replies of targets on the signals received via the sum and difference channels and carrying out monopulse processing and RSLS processing on the replies.

Abstract: A radar is provided which is mechanically and functionally independent of the primary radar; applies the principles of separation of emission pattern for each interrogation of any mode; of reception pattern for each reply of any mode; of assignment of the tasks which are specific thereto to distinct units. The radar includes one or more SSR/IFF interrogators dedicated at one and the same time to SSR surveillance and to gathering new mode S targets; and includes one or more other SSR/IFF interrogators for selective surveillance dedicated to mode S surveillance and to directed interrogations of IFF identification. The radar ensures simultaneous emission of the interrogations of the SSR/IFF interrogators in different azimuths, this simultaneous emission being enabled when the azimuthal spacing of the beams formed in emission ensures a decoupled level of jamming at the level of the transponders of the aircraft between the interrogations emitted by the respective sidelobes of the beams formed in emission.

Abstract: Each pattern being associated with a reception channel, over a given time period, the unsolicited asynchronous replies, of long ADS-B squitters type, transmitted by targets present in the airborne environment of the radar, are detected, each of the squitters containing position information on the target which transmits it; for each detection, the long ADS-B squitter is decoded to check that the detected target is located in accordance with the position information contained in the squitter, the non-conforming detections being rejected; for each detection retained, the time of the detection, the value of the azimuth of the main beam of the antenna and the received power value on each of the reception channels is associated with the detection, the position information contained in the squitters giving the elevation segment wherein the detection is situated; the values obtained over the period being stored, the measured patterns being sampled, by elevation segment, from the stored values.

Abstract: A radar is equipped with a main antenna having three radiation patterns, sum, difference and control, corresponding to the antenna, the radar comprises an auxiliary antennal device, composed of an antenna and of a rear radiating element which is situated at the rear of the antenna, fixed above the antenna and coupling means, the auxiliary antennal device: having three radiation patterns, sum, difference and control, the control pattern ensured for the direction opposite to the antenna by the rear radiating element; the antenna inclined to guarantee a maximum gain of its sum pattern in the elevational domain (60°-90°).

Abstract: An ADS-B spoofer being an false ADS-B squitter, an ADS-B squitter being an aircraft position information signal transmitted to secondary radars, the ADS-B squitters being detected over time at different bearings of the antenna in rotation of the radar, the method comprises, for each secondary radar, at least the following steps: a first step of detection of an ADS-B spoofer; a second step of location of the position in azimuth of the ADS-B spoofer generator, the second step comprising the following operations: measurement of the azimuth of the antenna of the secondary radar and of the received powers on the sum, difference and control patterns of the antenna upon the detection of an ADS-B squitter; generation and storage of at least one assumption of azimuth of the spoofer for each ADS-B squitter detected, the assumption being equal to the sum of the azimuth of the antenna and of the estimated bearing of the spoofer, the estimated bearing being characterized by the ratio of the received power on the sum patte

Abstract: A test method in operational phase includes three distinct steps, a first step using the replies of the transponder to the interrogations in the Mode S transmitted in operational mode by the secondary radar to perform the measurement of the power of the transponder, and the measurement of the average rate of reply to the interrogations in Mode S transmitted by the radar intended for it; a second step which performs the measurement of the sensitivity of the transponder and a third step which carries out the test of its maximum rate of reply. The second step and the third step are carried out by modifying the operating parameters of the radar so that the additional interrogations required for the measurement can be performed, during the time interval following the last operational interrogation during which the aircraft remains located within the main Sum channel lobe of the antenna of the radar.

Abstract: An each pattern is provided a reception pathway, the method uses the synchronous replies and the asynchronous replies, unsolicited of Fruit type, transmitted by targets present in the aerial environment of the radar and detected over a given number of antenna revolutions. At each detection of a reply the value of its off-aim in bearing and the value of relative power received on each of the pathways are calculated as is its elevation by extrapolation with the synchronous detections close to the same target and associated with the detection. The values obtained over the given number of revolutions are stored, the measured patterns being sampled on the basis of the stored values.