US 4,719,465 A · Monopulse radar equipment

Abstract

A monopulse radar equipment is developed which comprises first and second radiators arranged in symmetrical positions with respect to the boresight axis to radiate radar pulses in a predetermined cycle and thus to produce first and second directional radiation patterns, a beam forming network for synthesizing in an in-phase and opposite-phase relation the first and second directional radiation patterns of the first and second radiations into sum and different patterns, and a multichannel receiver for forming from the sum and difference patterns an off-boresight signal representing a deviation of a target object from the boresight direction and a sidelobe suppressed signal resulting from suppressing a sidelobe response of the sum pattern. The first and second directional couplers are interposed on the sum and difference pattern signal transmission channels between the beam forming network and the multichannel receiver. The first and second calibration signals of the same amplitude and phase are injected onto the sum and difference pattern signal transmission channels through the first and second directional couplers. The calibration signal is detected at the output terminal of the multichannel receiver and the phase characteristics between the sum and difference pattern signal transmission channels are compensated for in accordance with a result of detection.

Claims25

Dependent claims

A monopulse radar equipment comprising:

first and second radiators arranged in symmetrical positions with respect to a boresight axis for radiating radar pulses in a predetermined cycle and for producing first and second directional radiation patterns;
beam forming means for synthesizing the first and second directional radiation patterns, in an in-phase and opposite-phase relation and for producing a sum radiation pattern signal and a difference radiation pattern signal;
a multichannel receiver for generating, from the sum and difference pattern signals, an off-boresight signal representing a deviation of a target object from the boresight axis;
first and second directional couplers arranged in sum and difference pattern signal transmission channels between the beam forming means and the multichannel receiver;
calibration signal generating means connected to the first and second directional couplers for injecting first and second calibration signals into the sum and difference pattern signal transmission channels;
and
compensating means connected to an output of the multichannel receiver for detecting the calibration signal and for compensating for a phase characteristic and/or an amplitude characteristic of the sum and difference pattern signal transmission channels in accordance with a result of detection.

4 more elements

A monopulse radar equipment comprising:

first and second radiators arranged in symmetrical positions with respect to a boresight axis for radiating radar pulses in a predetermined cycle and for producing first and second directional radiation patterns;
beam forming means for synthesizing the first and second directional radiation patterns in an in-phase and opposite-phase relation and for producing a sum radiation pattern signal and a different radiation pattern signal;
a multichannel receiver connected to said beam forming means through a rotary joint and having two channels which are respectively connected to the sum radiation pattern signal and the difference radiation pattern signal, for generating, from the sum and difference pattern signals, an off-boresight signal representing a deviation of a target object from the boresight axis;
first and second directional couplers arranged in sum and difference pattern signal transmission channels between the beam forming means and the rotary joint;
calibration signal generating means, connected to the first and second directional couplers, for detecting a transmission signal passed through one of the sum and difference pattern signal transmission channels, and for injecting first and second calibration signals into the sum and difference pattern signal transmission channels after a predetermined time has elapsed after detecting the transmission signal;
and
compensating means connected to an output of the multichannel receiver for detecting the calibration signal and for compensating for a phase characteristic and/or an amplitude characteristic of the sum and difference pattern signal transmission channels in accordance with a result of detection.

4 more elements

Dependencies are inferred from the claim text.

Monopulse radar equipment

Life of this patent

Monopulse radar equipment

Life of this patent

Abstract

Claims25