Abstract: An angular scintillation reduction device used more especially in radar equipments making deviation measurements.It contains a circuit (60) receiving the video outputs of a radar receiver, the sum .SIGMA., range D and deviation measurement .epsilon. signals respectively on three terminals (3, 28 and 2). It delivers on a terminal (30) the values of the deviation measurement signal .epsilon. corresponding to the maximum values of the sum signal .SIGMA..It is applicable to all electromagnetic detection equipments which make deviation measurements.

Abstract: A system for tracking a moving target from a moving carrier. The tracking system is provided with a device for measuring the position of the target in relation to the carrier and with a servocontrol unit for servo controlling the aiming of the device. The error between the position of the target and a position estimated for it is given by the measuring device in spherical coordinates. The tracking system is further provided with a converting unit, in which the spherical coordinates are converted into cartesian coordinates. A frame of reference changing unit and a trajectory simulator of the target allow the position of the target to be calculated in relation to a cartesian frame of reference of unvarying orientation and fixed in relation to the earth.

Abstract: A system for tracking a moving target from a moving carrier. The system is provided with an arrangement allowing a measurement of the position of the target in relation to the carrier. The difference between the position of the target and an estimated position for the latter is given by this arrangement, generally in spherical co-ordinates. These spherical co-ordinates are changed by a co-ordinates converting unit into cartesian co-ordinates. The position of the target is given in turn in relation to a cartesian frame of reference of unvarying orientation whose origin is situated close to the instantaneous centre of rotation of the carrier in relation with a trajectory simulator. The frame of reference is then changed in the opposite direction for a control of the position of the measuring arrangement.

Abstract: An air navigation and landing aid system wherein a pair of transponder beacons are located at known positions adjacent an airport runway. The aircraft carries a weather pulse radar system and an antenna for furnishing information affording a navigation aid during the flight stage. Switching means are inserted between the antenna and the weather radar for switching, during the landing stage, the received pulses relating to each beacon, in response to the interrogation of the weather radar, to a special receiver and a processing circuit which furnishes information affording a landing aid.