RU95104775A - Radio altimeter - Google Patents

Abstract

FIELD: radio altimeters with linear frequency modulation with a modulation period varying depending on altitude. SUBSTANCE: the offered radio altimeter differs from the known ones by one fact that, with the aim of elimination of the systematic error caused by a charge of the kind of the reflecting surface, the radio altimeter additionally uses a narrow-band filter with a returnable central frequency, first envelope detector, summer, voltage-controlled oscillator, whose output is also connected to the complementing input of the time-to-code converter, frequency divider, whose output is connected to the control input of the narrow-band filter, and the second envelope detector, whose output is connected to the second input of the summer, and the input of the second envelope detector and input of the above filter are connected to the receiver output. EFFECT: enhanced accuracy.

Claims (1)

A radio altimeter (RV) with linear frequency modulation with a modulation period varying with height is proposed, which differs from the known ones in that in order to eliminate the systematic error due to a change in the type of reflecting surface, a narrow-band filter with a tunable central frequency, the first envelope detector is additionally introduced , adder, voltage-controlled integrator (VCO), the output of which is also connected to the counting input of the time converter - code, the frequency divider, the output of which is connected to directs input of the narrowband filter and a second envelope detector, whose output is connected to a second input of the adder and the input of the second envelope detector and an input of said filter connected to the receiver output.