RU95106258A - Radio altimeter - Google Patents

Abstract

FIELD: radio engineering. SUBSTANCE: device has serial circuit of generator of linear frequency modulation pulses, generator of sound and heterodyne signals, amplifier, decoupling unit, and antenna. In addition device has serial circuit of first mixer, receiver, ranging unit, synchronization unit which generates temporary substitution. First output of latter unit is connected to input of generator of linear frequency modulation pulses; its second output is connected to second input of generator of sound and heterodyne signals. Second output of latter unit is connected to one input of first mixer, which second input is connected to output of decoupling unit. In addition device has second mixer, which output is connected to two channels first of which has third band-pass filter, first squarer and first low-pass filter. Second channel has fourth band-pass filter, second squarer and third low-pass filter. In addition device has third mixer which output is connected to two channels in parallel. First channel has fifth band-pass filter, third squarer, second low-pass filter. Second channel has sixth band-pass filter, fourth squarer, fourth low-pass filter. Output of first low-pass filter is connected to serial circuit of first adder, first subtraction unit and second adder. Second input of first adder output of second low-pass filter. Two channels are connected in parallel to output of second adder. First of these channels has first amplitude detector, fifth low-pass filter, which is connected to control input of third tuned heterodyne which output is connected to second input of second mixer and to input of first averaging counter, which output is connected to second input of digital adder, which first input is connected to third output of synchronization unit. Said second channel has second amplitude detector, sixth low-pass filter, which is connected to control input of fourth tuned heterodyne, which output is connected to second input of third mixer and to input of second averaging counter, which output is connected to third input of digital adder, which output serves as one of device outputs. It provides information about flight height of satellite. Output of second low-pass filter is connected to serial circuit of second subtraction unit, which second input is connected to output of first low-pass filter, third subtraction unit, which output is connected to control input of controlled amplifier, which input is connected to second input of second adder. Output of third low-pass filter is connected to serial circuit of third adder, which second input is connected to output of fourth low-pass filter, first attenuator, which output is connected to second input of first subtraction unit, and second attenuator, which output is connected to second input of third subtraction unit. Output of third subtraction unit serves as second device output, which provides analog information about height of roughness of ground surface. EFFECT: increased range of unambiguous measurement of flight height in real-time scale while keeping constant precision.

Claims (1)

The radio altimeter refers to radio engineering and is intended to determine the satellite’s flight altitude, Earth’s gravitational field parameters, determine the geoid’s shape, land surface topography, topography of ice fields and the ocean, in particular, the height of ocean waves. The invention can also be used in the construction of precision range finders with a significantly expanded zone of unambiguous range measurement. The objective of the invention is the creation of RV with an extended zone of unambiguous measurement of flight altitude in real time on board the carrier without loss of measurement accuracy. The essence of the invention lies in the fact that the proposed radio altimeter comprises a serial connection of a LFM pulse generator, a driver of a probe and local oscillator signals, an amplifier, an isolation unit and an antenna, and a serial connection of the first mixer, receiver, range search unit, synchronization unit, and the formation of a temporary base. The technical result of the proposed radio altimeter is the expansion of the measurement unambiguity zone due to the appearance of a rough height reference scale, which makes it possible to use this RV to determine the topography of the land surface, the topography of ice fields and the ocean, as well as the parameters of the gravitational field of the Earth and the shape of the geoid.