JP2001165598A - Guided airframe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve a problem that a target cannot be trapped or tracked when the target has moved so that a target signal will not be out of the Doppler frequency range of a main lobe clutter. SOLUTION: The movement of the target, the Doppler frequency of a target signal, the Doppler frequency range of a main lobe clutter and the like are grasped to output an acceleration command to avoid the main lobe clutter through a clutter avoiding acceleration commanding unit whereby the track of a guided airframe is corrected and the target signal will not be superposed on the Doppler frequency range of the main lobe clutter or the time of superposing can be shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flying object for transmitting and receiving radio waves to capture and track a target.

[0002]

2. Description of the Related Art When the Doppler frequency of a target signal overlaps the Doppler frequency range of a main lobe clutter, the target loses its target because the power of the main lobe clutter is large.
It catches and tracks clutter and makes guidance to the target impossible.

FIG. 6 is a block diagram of a conventional guided flying vehicle designed to prevent this. As shown in FIG. 6, a conventional guided flying object includes an antenna unit 1 for radiating radio waves toward a target and receiving a reflected wave thereof, a transmitter unit 2 for supplying a transmission signal to the antenna unit 1, and an antenna. A receiver unit 3 that outputs the target Doppler frequency, direction, relative distance to the target, power of the target signal, etc. from the radio wave received by the unit 1, and outputs inertial information such as the position, velocity, and attitude angle of the flying object. Of the target, the relative motion between the target and the flying object obtained from the receiver unit 3 and the inertia information obtained from the inertial device unit 4, the motion of the target, the Doppler frequency range of the main lobe clutter, the main lobe clutter And a frequency tracking gate that alternately searches the upper and lower limits of the Doppler frequency range when the target signal overlaps with the Doppler frequency range of the main lobe clutter. When the Doppler frequency of the target signal approaches the Doppler frequency range of the main lobe clutter, the frequency gate control unit 6 moves the frequency tracking gate as shown in FIG. Stop tracking the target while the signal overlaps the Doppler frequency range of the main lobe clutter to avoid cluttering and tracking. In addition, the frequency gate control unit 6 moves the frequency tracking gate as shown in FIG. 7, so that the target signal is captured when the target signal comes out of the frequency range of the main lobe clutter, and tracking is started.

[0004]

However, in the above-mentioned conventional method, if the target moves so that the target signal does not fall out of the Doppler frequency range of the main lobe clutter, the target cannot be captured and tracked, and cannot be guided to the target. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and has an object to guide a flying object which prevents a target signal from overlapping a Doppler frequency of a main lobe clutter.
Another object of the present invention is to provide a guided flying object capable of reducing the overlapping time.

[0006]

In order to achieve the above object, the present invention provides an antenna unit for irradiating a target with radio waves and receiving a reflected wave thereof, and a transmission unit for supplying a transmission signal to the antenna unit. The receiver, which outputs the target Doppler frequency, direction, relative distance to the target, the power of the target signal, etc. from the radio wave received by the antenna, the position of the flying object,
The inertial device that outputs inertial information such as speed and attitude angle, the target's motion based on the relative relationship between the target and the flying object obtained from the receiver and the inertial information obtained from the inertial device, the main lobe clutter A calculation unit that outputs the Doppler frequency range, the reflected power of the main lobe clutter, the induced signal, etc., and the frequency tracking gate alternates the upper and lower limits of the Doppler frequency range when the target signal overlaps the Doppler frequency range of the main lobe clutter. A frequency gate control unit for controlling to search, a clutter avoidance acceleration command unit for calculating an acceleration command for preventing a target signal from overlapping the Doppler frequency range of the main lobe clutter, a guidance signal and a clutter output by the calculation unit A steering unit is provided that combines the acceleration command output from the avoidance acceleration command unit and performs steering control. The clutter avoidance acceleration command unit outputs an acceleration command to avoid the main lobe clutter when approaching or overlapping the Doppler frequency range of the latter, thereby correcting the trajectory of the guided flying object, and the Doppler of the target signal and the main lobe clutter. It is characterized in that the time in which the frequency ranges do not overlap or in which the frequency ranges overlap can be reduced.

In addition to the above-mentioned means, there is provided a power judging unit for judging whether or not tracking is possible by comparing the reflected power of the main lobe clutter with the target signal power, so that the target signal is in the Doppler frequency range of the main lobe clutter. When the vehicle approaches and overlaps, whether or not to output an acceleration command from the clutter avoidance acceleration command unit is determined by the determination of the power determination unit.

[0008] Further, an antenna unit for irradiating a radio wave toward a target and receiving its reflected wave, a transmitter unit for supplying a transmission signal to the antenna unit, a target Doppler frequency and direction from the radio wave received by the antenna unit , The relative distance to the target, the receiver unit that outputs the power of the target signal, etc.,
The inertial device that outputs inertial information such as speed and attitude angle, the target's motion based on the relative relationship between the target and the flying object obtained from the receiver and the inertial information obtained from the inertial device, the main lobe clutter A calculation unit that outputs the Doppler frequency range, the reflected power of the main lobe clutter, the induced signal, etc., and when the target signal overlaps the Doppler frequency range of the main lobe clutter, the frequency tracking gate sets the upper, lower, and upper limits of the Doppler frequency range , A clutter-avoidance acceleration command section that calculates an acceleration command that avoids overlapping of the target signal with the Doppler frequency range of the main lobe clutter, and an output from the calculation section. A steering unit that performs steering control by synthesizing a guidance signal to be generated and an acceleration command output by a clutter avoidance acceleration command unit; A tracking determination unit that determines whether the signal is a target signal or a main lobe clutter, and determines whether or not to track a signal detected when the target signal overlaps with the Doppler frequency range of the main lobe clutter by determining the tracking determination unit. It is characterized in that it is determined.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a structural view showing one embodiment of a guided flying object according to the present invention. The guided flying object has an antenna unit 1 for irradiating a target with radio waves and receiving the reflected wave, and is controlled so as to always point in the target direction.

The antenna unit 1 is connected to a transmitter unit 2 for supplying a transmission signal and a receiver unit 3 for outputting a target Doppler frequency, direction, relative distance to the target, power of the target signal, etc. from the received radio wave. Have been.

Further, the guided flying object of the present embodiment has an inertial device section 4 for outputting inertial information such as the position, velocity, and attitude angle of the flying object. The inertia information and the relative information between the target and the flying object output by the receiver unit 3 are input to the computer unit 5, and the target motion, the Doppler frequency range of the main lobe clutter, the reflected power of the main lobe clutter, the induced signal, etc. are calculated. I do.

The Doppler frequency range of the main lobe clutter is calculated based on the main lobe beam width of the antenna pattern of the antenna unit 1, the antenna directivity, and the speed information of the flying object. It is calculated based on body height, antenna pointing direction, antenna gain, sea surface reflection coefficient (fixed value), and the like.

A frequency gate control unit 6, a clutter avoidance acceleration command unit 7, and a steering unit 8 are connected to the computer unit 5. The frequency gate control unit 6 compares the Doppler frequency of the target signal output by the calculation unit 5 with the frequency range of the main lobe clutter, and stops tracking when the target signal overlaps the Doppler frequency range of the main lobe clutter. The gate is controlled so as to alternately search the upper and lower limits of the Doppler frequency range. Next, the target signal is captured when it comes out of the Doppler frequency range of the main lobe clutter, and tracking is started.

The clutter-avoidance acceleration command unit 7 is based on the target motion (discrimination between straight running and turning), the target Doppler frequency, and the Doppler frequency range of the main lobe clutter, as shown in FIG. The acceleration command for avoiding the main lobe clutter shown in FIG.
Output to

The steering unit 8 combines the guidance signal output by the calculation unit 5 and the acceleration command output by the clutter avoidance acceleration command unit 7 and performs steering control so that a required acceleration can be output, thereby performing guidance flying. Modify the body trajectory to reduce the time during which the Doppler frequency ranges of the target signal and the main lobe clutter do not overlap or overlap.

Embodiment 2 FIG. FIG. 3 is a structural diagram showing one embodiment of the guided flying object according to the present invention. FIG.
The same components as those described above are denoted by the same reference numerals and description thereof is omitted.

In FIG. 3, the power determining unit 9 includes a calculating unit 5,
It is connected to the clutter avoidance acceleration command unit 7 and the steering unit 8. The power determination unit 9 compares the power of the target signal output by the calculation unit 5 with the reflected power of the main lobe clutter. If the power of the target signal is larger than the power required to maintain tracking, the clutter avoidance acceleration is determined. The acceleration command output from the command unit 7 is not transmitted to the steering unit 8, but is transmitted in other cases.

When an acceleration command for avoiding clutter is transmitted to the steering unit 8, the flying trajectory shown in FIG. 4 is taken, and the guided flying object deviates from the shortest course for meeting the target and makes a large turn. Loss energy. Therefore, when the main lobe clutter does not hinder tracking and guidance of the target, the power determining unit 9 determines to avoid the main lobe clutter in order to reduce the loss of kinetic energy.

Embodiment 3 FIG. 5 is a structural diagram showing one embodiment of the guided flying object according to the present invention. FIG.
The same components as those described above are denoted by the same reference numerals and description thereof is omitted.

In FIG. 5, the full-coverage frequency gate control unit 10 is connected to the calculation unit 5 and the tracking determination unit 11. The all-cover frequency gate controller 10 compares the Doppler frequency of the target signal output by the calculator 5 with the frequency range of the main lobe clutter, and stops tracking when the target signal overlaps the Doppler frequency range of the main lobe clutter. , So that the frequency tracking gate sequentially searches the upper limit, the lower limit, and the inside of the Doppler frequency range. Next, when the target signal comes out of the Doppler frequency range of the main lobe clutter, or when the target signal overlaps with the Doppler frequency range of the main lobe clutter, it is determined that the signal detected by the tracking determination unit 11 is the target. At that time, the target signal is captured and tracking is started.

The tracking judging unit 11 is connected to the calculating unit 5 and the entire-cover type frequency gate control unit 10. The tracking determination unit 11 receives the signal output from the calculation unit 5 when the whole-coverage-type frequency gate control unit 10 positions the frequency tracking gate within the Doppler frequency range of the main lobe clutter, whether the detected signal is a target or a clutter. The determination is made based on the target information from the machine unit 3. As an example of the determination method, there is a method in which when the relative distance between the target and the flying object is changing smoothly, the target signal is considered. Usually, the main lobe clutter includes a distance component of several km or more. Therefore, when the main lobe clutter is detected, the relative distance cannot be specified. Therefore, when the relative distance of the detected signal changes smoothly, the signal may be considered as a target. However, it may be difficult to determine whether a target has been detected or clutter has been detected, depending on the distance measurement method. Therefore, the determination method needs to be determined in accordance with the system to be applied.

The guided flying object according to the present embodiment has the clutter avoidance acceleration command unit 7, so that the target signal flies so as not to overlap the Doppler frequency range of the main lobe clutter, or the overlapping time is shortened. Let's fly. However, in the case of firing in the beam quadrant or a target turning and making a U-turn, the target signal inevitably overlaps with the main lobe clutter. In such a case, the element for searching within the frequency range of the main lobe clutter and determining to perform the tracking when the target signal can be tracked is an entire-cover type frequency gate control unit 10.
And the tracking determination unit 11.

[0024]

As described above, according to the first aspect of the present invention, the antenna unit for irradiating radio waves and receiving the reflected wave from the target, the transmitter unit for supplying a transmission signal to the antenna unit, and the antenna unit A receiver unit that outputs target information from the received radio wave and an inertial device unit that outputs inertial information of the guided flying object, and target motion, target Doppler frequency, Doppler frequency range of main lobe clutter, etc. using those information The frequency gate control unit controls the frequency tracking gate so that the main lobe clutter is not captured and tracked, and the Doppler frequency range of the target signal and the main lobe clutter does not overlap with the clutter avoidance acceleration command unit ,
Or output an acceleration command that shortens the overlap time,
The steering unit combines the acceleration command with the guidance signal to control the steering, so even if the target moves so that the target signal does not fall out of the Doppler frequency range of the main lobe clutter, the guidance flying object will not An operation is performed so as to avoid main lobe clutter by an acceleration command output from the clutter avoidance acceleration command section, so that the target signal and the Doppler frequency range of the main lobe clutter do not overlap or the time during which the Doppler frequency range overlaps can be reduced.

According to the second aspect, the power determining section compares the reflected power of the main lobe clutter with the power of the target signal, and can track the target signal even when the Doppler frequencies of the target signal and the main lobe clutter overlap. In such a case, the acceleration command from the clutter avoidance acceleration command unit is configured not to be transmitted to the steering unit.If the main lobe clutter does not hinder the tracking and guidance of the target, the kinetic energy loss due to the clutter avoidance acceleration command Can be reduced.

According to the third aspect of the present invention, the target is searched for even in the Doppler frequency range of the main lobe clutter by the full-cover type frequency gate control unit, and the signal detected in the Doppler frequency range of the main lobe clutter by the tracking determination unit. Is determined to be a target or clutter, and in the case of a target, the signal is tracked, so that even if the target moves so that the target signal does not fall out of the Doppler frequency range of the main lobe clutter, If the power is greater than the power required for capturing and tracking than the reflected power of the main lobe clutter, the target can be captured and tracked.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a guided flying object according to Embodiment 1 of the present invention.

FIG. 2 is a diagram illustrating a case of an acceleration command output from a clutter avoidance acceleration command unit in a guided flying object according to Embodiments 1, 2, and 3 of the present invention.

FIG. 3 is a configuration diagram of a guided flying object according to Embodiment 2 of the present invention.

FIG. 4 is a diagram showing a flying trajectory of a guided flying object according to Embodiments 1, 2, and 3 of the present invention when a clutter avoidance acceleration command is output and when it is not output.

FIG. 5 is a configuration diagram of a guided flying object according to Embodiment 3 of the present invention.

FIG. 6 is a configuration diagram of a conventional guided flying object.

FIG. 7 is a diagram showing a setting position of a frequency tracking gate in a conventional guided flying object.

[Explanation of symbols]

Reference Signs List 1 antenna unit, 2 transmitter unit, 3 receiver unit, 4 inertia unit, 5 calculator, 6 frequency gate controller, 7
Clutter avoidance acceleration command section, 8 steering section, 9 power determination section, 10 whole area cover type frequency gate section, 11 tracking determination section.

Claims (3)

[Claims] An antenna unit for irradiating radio waves toward a target and receiving a reflected wave thereof, a transmitter unit for supplying a transmission signal to the antenna unit, and a target Doppler frequency based on the radio waves received by the antenna unit , The direction, the relative distance to the target, the power of the target signal, etc., the receiver unit, the inertial device unit that outputs inertial information such as the position, velocity, attitude angle of the flying object, and the receiver unit A calculation unit for outputting the target's motion, the Doppler frequency range of the main lobe clutter, the reflected power of the main lobe clutter, the guidance signal, etc. from the relative relationship between the target and the flying object and the inertial information obtained from the inertial device unit, A frequency gate control unit that controls the frequency tracking gate to alternately search the upper and lower limits of the Doppler frequency range when the target signal overlaps the Doppler frequency range of the main lobe clutter; A clutter avoidance acceleration command unit that calculates an acceleration command that avoids the target signal from overlapping the Doppler frequency range of the main lobe clutter; and an induction signal output by the calculation unit and an acceleration command output by the clutter avoidance acceleration command unit. A guided flying object, comprising: a steering unit that combines and controls steering. 2. A power judging unit for judging whether tracking is possible by comparing reflected power of the main lobe clutter and target signal power, and outputting an acceleration command from a clutter avoidance acceleration command unit based on the judgment result. The guided flying object according to claim 1, wherein: 3. An antenna unit for irradiating a radio wave toward a target and receiving a reflected wave thereof, a transmitter unit for supplying a transmission signal to the antenna unit, and a target Doppler frequency based on the radio wave received by the antenna unit. , The direction, the relative distance to the target, the power of the target signal, etc., the receiver unit, the inertial device unit that outputs inertial information such as the position, velocity, attitude angle of the flying object, and the receiver unit A calculation unit for outputting the target's motion, the Doppler frequency range of the main lobe clutter, the reflected power of the main lobe clutter, the guidance signal, etc. from the relative relationship between the target and the flying object and the inertial information obtained from the inertial device unit, When the target signal overlaps with the Doppler frequency range of the main lobe clutter, the whole area cover type that controls the frequency tracking gate to search the upper limit, lower limit and the range of the Doppler frequency range sequentially A frequency gate control unit, a clutter avoidance acceleration command unit that calculates an acceleration command that avoids overlapping of the target signal with the Doppler frequency range of the main lobe clutter, an induction signal output by the calculation unit, and a clutter avoidance acceleration command unit. A steering unit that combines the output acceleration command and performs steering control; and a tracking determination unit that determines whether to track a signal detected when the target signal overlaps the Doppler frequency range of the main lobe clutter. Guided flying object characterized by the following.