JP5186782B2 - Flying object guidance device - Google Patents

Description

  The present invention relates to a guidance device that performs synthetic band processing on a reflected signal from a target and guides a flying object toward the extracted target.

  A conventional guidance device transmits a radio wave toward a target, receives a reflected signal from the target, performs target detection processing on the received signal, detects the target signal, and obtains angle information, speed information, and distance information. Obtained and guided the flying body towards the target. As an example of such a guidance device, a guidance device is known (see, for example, Patent Document 1).

JP 2003-215239 A (6th page, FIG. 2)

  A conventional guidance device detects and tracks a target signal by transmitting a radio wave toward the target and receiving a signal reflected directly from the target, but the reflected wave from the target is a clutter such as the sea surface or the ground surface. When a signal that passes through is received, it is recognized that the target is in a direction different from the target direction, and the clutter is tracked instead of the target, resulting in erroneous lock.

  The present invention has been made to solve such a problem. When the guidance device detects a target signal, the reflected signal from the target and the clutter can be separated, and the target can be accurately tracked. It is what makes it possible.

The flying object guiding apparatus according to the present invention transmits a pulse signal composed of transmission pulses of a predetermined repetition frequency to a target that is a flying object flying on a clutter such as the sea surface or the ground surface, and is reflected by the target. A flying object guidance device for guiding a flying object toward a target detected by performing synthetic band processing on the reflected signal, wherein the transmission pulse is divided into two parts in the first half part and the second half part in the pulse; A transmission pulse corresponding to one of the first half part and the second half part is transmitted toward the target direction, and a transmission pulse corresponding to the other is transmitted toward the clutter direction, and the reflected signal from the target direction is combined. By performing band processing, the result of combined band processing in the target direction is acquired, and by performing combined band processing on the reflected signal from the clutter direction, the clutter direction matching is obtained. A combined band processing unit that acquires a band processing result, and a target detection unit that detects the target based on a combined band processing result obtained by subtracting the combined band processing result in the clutter direction from the combined band processing result in the target direction. And a guidance signal calculation unit that calculates a guidance signal for guiding the flying object toward the target detected by the target detection unit.

  According to the present invention, when the guidance device detects the target signal, the reflected signal from the target and the clutter can be separated, so that the influence of the clutter can be reduced and the target can be tracked at an accurate angle. Guidance performance is improved.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a flying object guiding apparatus according to Embodiment 1 of the present invention. The flying object guiding device of the present invention transmits a pulse signal at a predetermined pulse repetition frequency (PRF), extracts a target by performing a synthetic band process on the reflected signal, and targets the flying object as a target. Guide towards.
In FIG. 1, 1 is a guidance device, 2 is a target, 3 is a local oscillation unit that outputs a transmission frequency signal and a local signal according to a transmission / reception frequency setting signal, and 4 is a transmission unit that outputs a transmission signal obtained by amplifying the transmission frequency signal. Is an antenna unit that transmits a transmission signal to space and receives a reflected signal from the target, 6 is an antenna angle control unit for controlling the antenna unit 5 in the target direction and the clutter direction within the transmission pulse, and 7 is from the target 2 A receiving unit that converts the frequency of the reflected signal of the received signal with a local signal output from the local oscillating unit 3 and amplifies it to output a video signal; 9 is an A / D result distribution unit that distributes the digital signal from the A / D conversion unit 8 into a signal from the target direction and a signal from the clutter direction, and 10 is each of the distributed A / D results. Then, the synthetic band processing unit 11 that performs the synthetic band processing, 11 removes clutter by taking a difference with respect to the target direction synthetic band processing result and the clutter direction synthetic band processing result calculated by the synthetic band processing unit 10. The combined band processing result difference processing unit to be implemented, 12 is a target detection unit for detecting a target from the combined band processing result from which clutter is removed, and 13 calculates distance, speed, and angle information from the detected target signal, and calculates a guidance device. An induction signal calculation unit 18 that outputs an induction signal for induction toward the target, and a trigger generation unit 18 that outputs a trigger signal for switching between the target direction and the clutter direction.

Next, the operation will be described with reference to FIGS.
2A and 2B are diagrams for explaining the state of radiation and reflection with respect to the target direction, FIGS. 3A and 3B are views for explaining the state of radiation and reflection with respect to the clutter direction, and FIG. 4 is a clutter. FIG. 5A is a diagram for explaining how to determine a direction, FIG. 5A is a diagram for explaining an A / D sampling situation of a received wave, and FIGS. 5B to 5D are diagrams for explaining a flow of signal processing.
2 and 3, reference numeral 1 denotes a guidance device that flies toward a target, 2 denotes a target that the flying object 1 captures and tracks, 14 denotes a sea surface or ground surface, and 17 denotes a mother machine.
As illustrated in FIG. 2A, first, the guidance device 1 receives target information from the mother machine 17. Based on this target information, the antenna angle control unit 6 sets the antenna angle of the antenna unit 5 in the target direction (θ1), and radiates the first half of the transmission pulse toward the target direction (FIG. 2B). The antenna unit 5 receives a reflected wave (here, referred to as a target signal) in which the first half of the transmission pulse is reflected by the target 2 and a clutter reflected wave reflected by the sea surface or the ground surface 14.
Next, as shown in FIG. 3A, the antenna angle control unit 6 sets the antenna angle of the antenna unit 5 to the clutter direction, that is, the direction (θ2) in which the target 2 is outside the effective reception angle range, The second half of the transmission pulse is emitted outside the target direction (FIG. 3B). In this way, the antenna unit 5 receives only the clutter reflected wave in which the latter half of the transmission pulse is reflected by the sea surface or the ground surface 14.

Here, how to determine the clutter direction (θ2) in which the target 2 is outside the effective reception angle range will be described with reference to FIG.
First, the received power reduction amount (ΔP = P_th−P_n) is calculated from the difference between the target signal level (P_th) and the noise level (P_n) required for target detection. Next, using a known antenna pattern, an angle (Δθ) at which the gain decreases by ΔP from the peak gain of the antenna is obtained. Thus, when the target direction (θ1) is shifted by Δθ, the angle does not affect the target signal. This is the clutter direction (θ2 = θ1 + Δθ).

As described above, the first half of the transmission pulse is emitted toward the target direction, and the second half is emitted toward the clutter direction by switching the direction of the antenna (FIGS. 2 and 3). Therefore, also in the received reflected wave, the first half of the reflected wave is a reflected wave from the target direction, and the second half is a reflected wave from the clutter direction.
As shown in FIG. 5A, the A / D conversion unit 8 performs A / D at a sampling rate at which A / D sampling is performed twice on the reflected wave, and performs a target direction and a target direction for each pulse. A / D sampling results for each of the clutter directions are acquired once (AD_T, AD_C).

Next, the A / D result distribution unit 9 converts the A / D sampling results into A / D results (AD_T (1) to AD_T (N)) for the target direction and A / D results (AD_C (1) to) for the clutter direction. AD_C (N)) (see FIG. 5B). At this time, the A / D result is distributed based on the trigger signal output from the trigger generator 18 to synchronize with the transmission pulse.
Next, the synthesis band processing unit 10 uses the A / D sampling results distributed by the A / D result distribution unit 9 as A / D results (AD_T (1) to AD_T (N)) for the target direction and A for the clutter direction. / D results (AD_C (1) to AD_C (N)) are each subjected to synthesis band processing (see FIG. 5C). As a result, the signal that was on the frequency axis is converted into a signal on the distance axis (time axis).
The synthetic band processing result difference processing unit 11 performs a process of obtaining a difference between the synthetic band processing result in the target direction converted into the distance axis and the synthetic band processing result in the clutter direction (see FIG. 5D). The later result is output to the target detection unit. After the difference processing, the clutter signal is removed from the synthesis band processing result in the target direction.

As described above, the flying object guiding apparatus according to the first embodiment includes the trigger generation unit 18, the antenna angle control unit 6, the A / D result distribution unit 9, and the combined band processing result difference processing unit 11. The antenna angle control unit 6 and the A / D result distribution unit 9 are operated in synchronization with each other on the basis of the trigger signal output by the. Thus, during the period of transmitting one transmission pulse, the output destination of the reflected wave received by the antenna is switched in conjunction with the switching operation for switching the antenna direction between the target direction and the clutter direction. Then, the combined band processing result difference processing unit 11 takes the difference between the combined band processing result in the target direction and the combined band processing result in the clutter direction so as to remove the clutter signal from the combined band processing result in the target direction. did.
As a result, the influence of clutter can be reduced, the target can be tracked at an accurate angle, and the flying object guidance performance can be improved.

Embodiment 2. FIG.
FIG. 6 is a block diagram of a flying object guiding apparatus according to Embodiment 2 of the present invention. In the first embodiment, the clutter signal is removed from the synthesis band processing result in the target direction. However, in the second embodiment, the distance (clutter distance range) where the clutter exists is calculated and the distance other than the clutter distance range is calculated. Is determined as a target detection range. In FIG. 6, reference numeral 15 denotes a target detection range calculation unit. Note that the same or corresponding components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.
The target detection range calculation unit 15 compares the target direction combined band processing result and the clutter direction combined band processing result, calculates the distance (clutter distance range) where the clutter signal exists, and sets the target detection range. The target detection unit 12 performs target detection from the result of the target detection range calculation unit 15. The guidance signal calculation unit 13 obtains and outputs a guidance signal for guiding the guidance device toward the target.

Next, the operation of the guidance device according to the second embodiment will be described with reference to FIG.
The operations up to the synthesis band processing unit 10 are the same as those in the first embodiment. FIG. 7 shows the flow of processing of the target detection range calculation unit 15. The target detection range calculation unit 15 compares the combined band processing result for the target direction calculated by the combined band processing unit 10 with the combined band processing result for the clutter direction (see FIG. 7A). The distance (clutter distance range) where the clutter signal exists is calculated from the combined band processing result for the clutter direction, and a distance other than the clutter distance range is determined as the target detection range (see FIG. 7B). The target detection unit 12 performs target detection on the target detection range determined by the target detection range calculation unit 15.
Since there is no clutter signal in the target detection range, the same effect as removing the clutter can be obtained.

  As described above, according to the second embodiment, the distance (clutter distance range) in which the clutter signal exists is calculated from the combined band processing result with respect to the clutter direction, so that the target detecting unit 12 can detect the target. The target detection range can be narrowed. Thereby, when the guidance device 1 tracks the target 2, the target can be tracked at a more accurate angle without being affected by the clutter reflection wave, and the flying object guidance performance can be improved.

Embodiment 3 FIG.
FIG. 8 is a block diagram of a flying object guiding apparatus according to Embodiment 3 of the present invention. In FIG. 8, 16 is an A / D result difference processing unit. In the first embodiment, the clutter signal is removed from the result after the synthesis band processing in the target direction. However, the clutter signal may be removed before the synthesis band processing. Note that the same or corresponding components as those in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted.
The A / D result difference processing unit 16 removes clutter by taking a difference for each A / D result distributed by the A / D result distribution unit 9. The result of the A / D result difference processing unit 16 is subjected to synthesis band processing by the synthesis band processing unit 10, target detection is performed on the signal by the target detection unit 12, and the guidance signal calculation unit 13 directs the guidance device toward the target. Calculate the guidance signal to guide.

Next, the operation of the guidance device according to Embodiment 3 will be described with reference to FIG.
The operations up to the A / D result distribution unit 9 are the same as those described in the first embodiment. FIG. 8 shows the signal processing flow of the processing after the A / D result distribution unit 9. The A / D result distribution unit 9 distributes the A / D result for the target direction and the A / D result for the clutter direction, and the A / D result difference processing unit 16 converts the two types of A / D results. Take the difference. The A / D result is a signal on the frequency axis, and a clutter signal on the frequency axis is removed by taking a difference before processing the synthesis band. By performing synthesis band processing on this signal in the synthesis band processing unit 10, only the target signal from which the clutter signal has been removed on the distance axis is output.

As described above, according to the third embodiment, since it is possible to remove the clutter component separated in frequency from the target, when the guidance device 1 tracks the target 2, it is not affected by the clutter reflected wave, The target can be tracked at an accurate angle, and the guidance performance is improved.

It is a figure which shows the structure of the flying body guidance apparatus which concerns on Embodiment 1 of this invention. It is a figure explaining the condition of radiation | emission and reflection with respect to the target direction of the flying body guidance apparatus which concerns on Embodiment 1 of this invention. It is a figure explaining the condition of the radiation | emission and reflection with respect to the clutter direction of the flying body guidance apparatus which concerns on Embodiment 1 of this invention. It is a figure explaining how to determine the clutter direction of the flying object guidance apparatus according to Embodiment 1 of the present invention. It is a figure explaining the flow of the signal processing of the flying body guidance apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the flying body guidance apparatus which concerns on Embodiment 2 of this invention. The flow of the process of the target detection range calculation part of the flying body guidance apparatus which concerns on Embodiment 2 of this invention is demonstrated. It is a figure which shows the structure of the flying body guidance apparatus which concerns on Embodiment 3 of this invention. FIG. 10 is a diagram illustrating a flow of received signal processing in the third embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Guidance device, 2 Target, 3 Local oscillator part, 4 Transmitter part, 5 Antenna part, 6 Antenna angle control part, 7 Receiving part, 8 A / D conversion part, 9 A / D result distribution part, 10 Synthesis band process part , 11 Synthetic band processing result difference processing unit, 12 Target detection unit, 13 Guide signal calculation unit, 14 Sea surface or ground surface, 15 Target detection range calculation unit, 16 A / D result difference processing unit, 17 Mother machine, 18 Trigger generation unit .

Claims (4)

Transmits a pulse signal composed of the transmitted pulse having a predetermined repetition frequency to the target is a flying object for flying over clutter such as sea surface or ground surface, to synthesize band processing reflected reflected signal by the target A flying object guidance device for guiding the flying object toward the target detected by
The transmission pulse is divided into the first half and second half in a pulse, the transmission pulses corresponding to one of said first half portion and the latter half portion and transmitted to the target direction, towards the transmitting pulses corresponding to the other in the clutter direction An antenna unit for transmission;
A synthetic band process is performed on the reflected signal from the target direction to obtain a synthetic band processing result in the target direction, and a synthetic band process is performed on the reflected signal from the clutter direction to obtain a synthetic band in the clutter direction. A synthetic band processing unit for obtaining a processing result;
A target detection unit for detecting the target based on a combined band processing result obtained by subtracting the combined band processing result in the clutter direction from the combined band processing result in the target direction;
A guidance signal calculation unit for calculating a guidance signal for guiding the flying object toward the target detected by the target detection unit;
A flying body guidance device characterized by comprising: An antenna angle control unit for controlling a transmission angle of the antenna unit;
A receiving unit that outputs a video signal based on a reflected signal received by the antenna unit;
An A / D converter for converting the video signal into a digital signal;
A distribution unit that distributes the digital signal into a reflected signal from the target direction and a reflected signal from the clutter direction;
The A / D converter performs A / D conversion at a sampling rate at which A / D sampling is performed twice on the reflected signal, and outputs the A / D conversion result for each of the target direction and the clutter direction once. Obtain and output to the distributor,
The distribution unit distributes the digital signal into a signal from a target direction and a signal from a clutter direction based on a trigger signal having the sampling rate,
  The flying object guidance device according to claim 1, wherein the antenna angle control unit controls the antenna angle in the target direction and the clutter direction based on the trigger signal. The antenna angle control unit initially controls the angle of the antenna unit based on target information received from the outside, and then sets the target direction detected by the target detection unit as a new target direction. The flying object guiding apparatus according to claim 2, wherein an angle is controlled. Transmits a pulse signal consisting of transmission pulses of a predetermined repetition frequency to a target that is a flying object flying over clutter such as the sea surface or the ground surface, and performs a synthetic band process on the reflected signal reflected by the target A flying object guidance device for guiding the flying object toward the target detected by
The transmission pulse is divided into a first half part and a second half part in the pulse, a transmission pulse corresponding to one of the first half part and the second half part is transmitted toward the target direction, and a transmission pulse corresponding to the other is directed toward the clutter direction. An antenna unit for transmission;
A synthetic band process is performed on the reflected signal from the target direction to obtain a synthetic band processing result in the target direction, and a synthetic band process is performed on the reflected signal from the clutter direction to obtain a synthetic band in the clutter direction. A synthetic band processing unit for obtaining a processing result;
A distance where clutter is present is calculated from the combined band processing result in the clutter direction, a range excluding the distance is set as a target detection range, and a target is determined based on the target detection range and the combined band processing result in the target direction. A target detection unit to detect;
A flying body guidance device characterized by comprising:

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