DOPPLER SENSOR OF COMPONENTS OF VELOCITY VECTOR, ALTITUDE AND LOCAL VERTICAL FOR HELICOPTERS AND VERTICAL LANDING SPACE VEHICLES Russian patent published in 1997 - IPC

FIELD: independent navigation of flight vehicles and blind landing of helicopters and space vehicles on an unprepared area. SUBSTANCE: the device provides for measurement of components of the velocity vector from the maximum to zero ones and with a sign inversion, measurement of altitude from the close to zero to maximum one (helicopter ceiling) and measurement of inclination of landing area relative to the construction line of the flight vehicle. The sensor uses three-four-beam aerials, microwave-FM transmitter, two-channel radio-frequency head, two-channel wide-band amplifier at modulation frequency, digital unit for determining the Doppler frequency and range phase, synthesizer- synchronizer and a number of other, mainly computing, units. For discrimination of the phase signal the unit for determining the Doppler frequency and range phase uses the method, in which the input signal is divided into two components: one formed by the Doppler shift of the upper side frequency, and the other formed by the Doppler shift of the lower side frequency of radiated signal. The obtained components are multiplied together. Separation of signals occurs after filtration in the fast Fourier transform unit. The synthesizer-synchronizer has digital equipment elements for generation of modulation and a number of other signals, which provides for a high accuracy of phase lock of a number of signals to the phase of the modulation signal irrespective of wobbulation according to the step-sawtooth law. EFFECT: enhanced reliability. 3 cl, 7 dwg