JP3495271B2 - Jammer modulator - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modulator for a jammer that interferes with radar operation. A radio wave jammer that receives a radio wave such as a chirp radar (which contains a high-frequency carrier in the pulse) and cancels the wave is a pulse wave because the interfering wave is pulse-compressed by the signal processor of the opponent radar. The width becomes shorter and the obstruction duty decreases. The present invention relates to a jamming radio wave modulation circuit intended to reduce a decrease in jamming duty by modulating a received radar pulse. Further, it can be applied to a radar beacon or the like that takes in a partner radar wave, amplifies and retransmits it.

[0002]

2. Description of the Related Art FIG. 18 shows an example of the configuration of a conventional modulator circuit for an interference device using a waveform storage circuit. This interferometric modulator is composed of a waveform storage / reproduction means 1, a waveform detection means 2, a Doppler modulation means 3 and a control means 4. Waveform memory /
The reproducing means 1 receives the radar chirp wave, converts it digitally, and stores it. The output of the waveform storage / reproduction means 1 is given to the Doppler modulation means 3.

On the other hand, the radar chirp wave is also given to the waveform detecting means 2, which detects the rising and falling edges of the waveform and gives them to the controlling means 4. Waveform control information is given to the control means 4, and the waveform storage / reproduction means 1 is supplied.
A storage / reproduction control signal and a Doppler modulation control signal to the Doppler modulation means. The waveform storage / reproduction means 1
Is output to the Doppler modulation means 3.

The waveform storing / reproducing means 1 is generally composed of a semiconductor memory, and the semiconductor memory performs analog / digital conversion of the radar chirp wave whose frequency is converted into a storage frequency band and stores it in a digital memory. In addition, the stored waveform is reproduced at an arbitrary timing and output after digital / analog conversion.

Normally, this waveform is subjected to Doppler modulation to simulate a radar echo in which a radar wave is reflected back from a moving target (the Doppler modulation is required only when the other radar carries out moving target detection (MTI)). Then, the Doppler modulation frequency changes depending on the target moving speed.) Next, the operation of this interferometric modulator will be described. First, the control means 4 sends a waveform storage trigger in accordance with the predicted arrival time of the opponent radar wave, and stores the radar chirp wave in the waveform storage / reproduction means 1. At the same time, the waveform detection means 2 detects the rising / falling position (in the case of a digital memory, means an address) of the radar pulse signal, and the signal from the control means 4 repeatedly reproduces only the radar pulse portion. Control. According to the instruction from the control means 4 for the waveform, the Doppler modulation means 3
Doppler modulation is applied by and transmitted as an interfering wave. Generally, a circuit that operates in this way is called a repeater circuit.
According to this example, since the Doppler modulation unit 3 repeatedly transmits the waveform, the counterpart radar cannot determine which pulse is the response pulse, and the target cannot be positioned.

FIG. 4 is an explanatory diagram of the interfering wave and the radar echo timing in the partner radar. 100 in the figure
Is a counterpart radar, and 111 is an interfering device that sends an interfering wave toward the radar 100. Here, the interference state and the radar echo timing in the partner radar when the interference is performed using the conventional interference modulator with respect to the radar that performs pulse compression will be described, and the interference state will be described.

◯, Δ, □, and ◇ shown in the figure are targets. Based on the partner radar 100, there is a target ◯ in the azimuth θ1 distance R1, a target Δ in the azimuth θ2 distance R2, a target □ in the azimuth θ3 distance R3, and a target ◇ in the azimuth θ4 distance R4. Jammer 11
Reference numeral 1 indicates a situation in which a disturbing operation is performed from the side of the radar 100. Here, the distance R1 is expressed by the following equation.

R1 = (3 × 10 ⁸ ) × t1 / 2/3 × 10 ⁸ is the speed of light. t1 is the time until the pulse is reflected and returns.

In the radar reception signal, when the antenna of the radar 100 faces the radar target azimuth with reference to the transmission timing, the radar echoes from the targets (○, Δ, □, ◇) are time t1, t2, t3, t4. Come back. Further, the interfering wave repeats the received radar wave, so that the interference wave overlaps with the radar echo and is received by the radar.

This received pulse width is the same as the transmitted pulse width of the radar 100, but is compressed by the processor to a compression ratio of 1 / pulse with the center of the pulse as a reference, and the pulse width is shortened. In the portion where the interference wave and the radar echo overlap, the radar echo cannot be detected and the interference becomes effective timing.

As is clear from the timing diagram, the target □
Only the target cannot be detected, and the targets ○, △, and ◇ can be detected. That is, since the interference wave is also compressed by the pulse compression, even if the interference wave covers the entire timing in the radar reception signal, there is a timing at which no interference occurs after the signal processing.

FIG. 6 shows a state in which an interfering wave is displayed in the form of a radar scope and a modulation method in this state. Figure 6
FIG. 4 is an explanatory diagram of a conventional interference modulation method. In the received radar chirp waveform (pulse width τ, chirp bandwidth B) shown here, one pulse of the pulse repeatedly transmitted while the radar scans the antenna is extracted.

In the figure, modulation for one pulse of the received radar waveform is shown as an interfering waveform. In the figure, modulation for one pulse of the received radar waveform is shown as an interfering waveform. The received radar chirp waveform is modulated at the Doppler modulation frequency fd, the pulse width τ and the chirp bandwidth B are maintained, and the interference wave is continuously transmitted.

In the partner radar scope, the horizontal axis represents the azimuth and the vertical axis represents the distance, and the radar target (◯, Δ, □, ◇) is displayed as dots at the detected azimuth and distance. Since the interfering wave is pulse-compressed (the width of the pulse becomes short) similarly to the radar echo by the signal processor of the opponent radar, the interfering wave is displayed as a band on the enemy radar scope. The band-like shape is tj (shown in FIG. 4) in which the interfering wave is displayed on the radar with reference to the transmission timing of the radar.
Is transmitted in such a way as to be constant. If tj
When is changed, the interfering wave is displayed as dots at a distance corresponding to the delay amount, so that it does not become a band.

The degree of band-like narrowing on the scope is determined by the compression ratio of the signal processor. The relational expressions are shown below. Duty = 1 / compression ratio compression ratio = pulse width (τ) × chirp frequency band (B) Here, if the compression ratio is 6, the pulse width of the interfering wave is 1 / pulse width in the signal processor of the radar. Becomes 6,
The ratio of disturbing waves appearing on the scope is 1/6. Therefore, the higher the compression ratio, the narrower the interference wave becomes on the scope.

Interfering waves are displayed in a band on the scope, and the other portions can detect the target. Specifically, in the partner radar scope, the □ radar target cannot be detected, but ◯, Δ, and ◇ will be detected.
In other words, the smaller the obstruction display portion on the scope, the more the radar can detect the target, which means that the obstruction effect is low. Therefore, the disturbing effect becomes lower with high pulse compression.

Here, the demerit of the display ratio of the disturbing wave has been described. However, since the disturbing wave is also pulse-compressed like the radar echo, the disturbing power is equivalently increased and the transmitter output of the disturbing device is increased. There is a merit that can lower.

Incidentally, for a radar that is not pulse-compressed, it is possible to display an interfering wave on the scope surface by a conventional method, so that there is no problem in the conventional modulation format. The reason why the recent radar uses the pulse compression technique is that the transmission power can be increased equivalently. Also, advances in digital technology have facilitated configuration and are moving toward higher pulse compression.

As described above, the equivalent interference power is improved by simply hitting back the opposite radar chirp by the conventional interference modulation format (repeater operation) for the recent radar that uses pulse compression. Although it was effective in terms of points, there is a problem that the obstruction duty becomes low and the obstruction effect lowers it.

[0020]

If the interference wave having the center frequency of the radar chirp wave is simply transmitted continuously, the interference wave is not pulse-compressed, so that the interference duty can be 100%. However, as described above, since there is no increase in the equivalent power due to pulse compression, it is necessary to increase the interference power by a compression ratio as compared with the case of transmitting a chirped interference wave. Therefore, similarly to the radar, it is impossible to obtain high power without taking a method of raising the interference power equivalently by capturing the enemy radar wave and canceling the chirp wave as in the radar.

In other words, a modulation method that improves the interference duty while making the most of the equivalent interference power of pulse compression is improved is ideal. However, in reality, it is impossible to increase the interference duty while maintaining the interference power (peak power value after pulse compression), and a method of applying a modulation to increase the duty instead of lowering the equivalent interference power becomes a problem. .

Reduction of peak power <-------> Improvement of duty This trade-off becomes particularly effective when the power of the interfering wave is higher than the radar echo level received by the radar.

Here, the reception level at which the interference wave power and the radar echo are input to the radar receiver will be described. FIG. 5 shows the relationship between the radar interference level and the radar reception level with respect to the radar target distance. The horizontal axis of the figure represents distance (logarithmic display), and the vertical axis represents reception level in logarithm (dB).

The radar echo S and the interfering wave level J have inclinations of -12 dB / octave and -6 with respect to distance, respectively.
Decreases in dB / octave. The interference radio wave reception level of the radar having a distance relationship as shown in FIG. 4 is J1, the radar echo levels from the radar target are S1, S2, S3,
It becomes S4.

As can be seen from this figure, the greater the distance of the radar target, the greater the difference X between the interfering wave and the radar echo level (X1 <X2 <X3 <X4). That is, the farther the radar target is, the more likely it is that interference will occur even if the peak power of the interference wave is low.

From this relationship, the further the radar target is, that is, the method of performing the modulation for increasing the duty with the passage of time when the interfering device receives the radar wave and returns the interfering wave.

The present invention has been made in view of the above problems, and it is an object of the present invention to provide a modulator for an interference machine capable of varying the equivalent interference power and the interference duty.

[0028]

(1) FIG. 1 is a block diagram showing the principle of the present invention. The same parts as those in FIG. 18 are designated by the same reference numerals. In the figure, 1 is a waveform storing / reproducing means for receiving and storing the radar chirp wave, and 2 is a waveform detecting means for detecting a pulse waveform, and 3 is a Doppler modulating means for applying a Doppler modulation. 5 is pulse detection information,
Waveform reading information calculating means for calculating information necessary for reading the waveform of the waveform storing / reproducing means 1 from the pulse cut-out information,
Reference numeral 4 is a control means for controlling each of the circuits.

According to the configuration of the present invention, the radar chirp wave is stored in the waveform storing / reproducing means 1, and at the same time, the pulse rising and falling positions of the radar chirp wave are detected by the waveform detecting means 2 and the detected information is used as a basis. In the case where the waveform read information calculation means 5 calculates the waveform read start position and the end position for cutting out the pulse, and the cut out pulse is repeatedly reproduced as a continuous pulse train and sent out as an interfering wave, the control means 4 Equivalent jamming power and jamming duty can be varied by finding the center of the pulse for continuously reproduced pulses, cutting out from the center with an arbitrary width, and having a modulation function that repeats shorter than the received pulse width. It is possible to provide a modulator for a jammer.

(2) In this case, the waveform storage /
In a circuit in which waveform synthesizing / forming means for synthesizing and forming waveforms is added after the reproducing means, the control means fetches the received radar chirp wave into the waveform storing / reproducing means,
The leading edge and the trailing edge of the pulse are amplitude-modulated in a slope shape, and the waveform synthesis / formation means forms a trapezoidal / triangular waveform to superimpose the slope portion of the waveform so that the amplitude becomes constant. It is characterized by having a modulation function of synthesizing waveforms and continuously reproducing so that the repeating interval is shorter than the pulse width and transmitting as an interfering wave.

According to the structure of the present invention, the waveform synthesizing / forming means 10 performs trapezoidal / triangular waveform shaping, and the slopes of the waveforms are overlapped, so that the repetition interval becomes shorter than the pulse width. It can be regenerated and the interference wave can be transmitted.

(3) Further, the waveform synthesizing / forming means is
1 / N to N / N of pulse width of received radar chirp wave
The pulse waveform is delayed for each time and repeatedly played,
It is characterized in that it has a modulation function of superposing and synthesizing N waveforms being simultaneously reproduced by the waveform synthesizing / forming means so that the amplitude is constant, and continuously transmitting them as an interfering wave.

According to the configuration of the present invention, it is possible to continuously transmit as an interfering wave. (4) Further, the control means is characterized in that the pulse width that is cut out from the pulse and continuously reproduced is shortened with the lapse of time, and the pulse repetition period is shortened.

According to the structure of the present invention, it is possible to send out an interfering wave whose repetition cycle is sequentially shortened with the passage of time. (5) Further, the control means makes the slopes of the leading edge and the trailing edge of the pulse gentle as the time of continuous reproduction elapses to increase the overlap time of the slope portion and accelerate the pulse repetition period. I am trying.

According to the structure of the present invention, it becomes possible to send out the interfering wave with the slope superposition time increased with a lapse of time. (6) Further, the control means is characterized by increasing the number N of simultaneous reproductions with the lapse of time of continuous reproduction.

According to the configuration of the present invention, it is possible to send out an interfering wave in which the number N of simultaneous reproductions is increased as the time of continuous reproduction elapses. (7) According to the second invention, a waveform storing / reproducing means for receiving and storing a radar chirp wave, a waveform detecting means for detecting a pulse waveform, a Doppler modulating means for performing Doppler modulation, and a waveform reading position. / Comprising a waveform read information calculation means for calculating a reproduction time and a control means for controlling each circuit, the radar chirp wave is stored by the waveform storage / reproduction means, and at the same time, the pulse rise of the radar chirp wave and The fall position is detected by the waveform detection means,
Based on this detection information, the waveform reading start position and end position for cutting out the pulse are calculated and read out, the cut-out pulse is repeated and reproduced as a continuous pulse train, and the Doppler modulation means performs Doppler modulation to send out as an interfering wave. In this case, the control means has a modulation function of obtaining a pulse central portion for the continuously reproduced pulse, cutting the pulse at an arbitrary width from the center, and repeatedly performing the pulse shorter than the received pulse width. .

According to the structure of the present invention, the radar chirp wave is stored in the waveform storing / reproducing means 1, and at the same time, the pulse rising and falling positions of the radar chirp wave are detected by the waveform detecting means 2 and the detected information is used as a basis. In the case of calculating the waveform reading start position and the end position for cutting out the pulse by the waveform reading information calculating means 5, reproducing the cut-out pulse repeatedly as a continuous pulse train, and performing Doppler modulation to send it as an interfering wave, the control is performed. The means 4 obtains the center of the pulse for this continuously reproduced pulse, cuts it out from the center with an arbitrary width, and has a modulation function of repeatedly performing shorter than the received pulse width. It is possible to provide a modulator for an interfering device that can change the.

[0038]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. Here, first, general operation will be described with reference to the conventional example shown in FIG. The jammer first captures the waveform to be disturbed in the "waveform capture phase". When the acquisition is completed, the "interfering phase" is entered, and the repeated reproduction wave of the acquired waveform is subjected to necessary modulation and transmitted as an interference wave.

That is, in the "waveform acquisition phase", when the radar signal to be disturbed is input to the jammer, the waveform detecting means 2 recognizes the rising / falling of the waveform,
The pulse waveform is detected. This result is input to the control means 4. On the other hand, the waveform storage / reproduction means 1 stores only the signal component detected by the pulse under the control of the control means 4.

When the "waveform capture phase" of the wave to be disturbed is completed, the "jamming phase" is entered next, and the waveform storage /
The waveform stored in the reproducing means 1 is continuously and repeatedly reproduced (read out), subjected to Doppler modulation by the Doppler modulation means 3, and then outputted as an interfering wave.

Next, an embodiment of the present invention will be described with reference to FIG. The difference from the conventional device shown in FIG. 22 is that the waveform read information calculation means 5 is added. The waveform read information calculation means 5 receives the output of the waveform detection means 2 and exchanges signals with the control means 4. The operation of the apparatus thus configured will be described below.

In the "waveform acquisition phase", when the radar signal to be disturbed arrives at the jammer, the waveform storing / reproducing means 1 unconditionally stores the signal waveform. At the same time, the signal waveform is input to the waveform detecting means 2, and the waveform detecting means 2 detects the presence / absence of a pulse at the rising edge and the falling edge of the waveform and outputs it to the waveform read information calculating means 5 as in the conventional case.

The waveform reading information calculating means 5 is necessary for reading the waveform from the waveform storing / reproducing means 1 based on the pulse detection information and the pulse cutout information (a parameter of what percentage width of the original pulse the pulse is cut out). Information (read start / end position, read cycle (cutout pulse width), pulse width, etc.) is calculated and given to the control means 4. Here, the read start / end position corresponds to the position (address) where the cutout pulse is stored, and the read cycle is the cutout pulse width (when the original pulse width is τ and the pulse cutout ratio is k, the cutout pulse Width = kτ). The pulse width means the pulse width τ before being cut out.

In the "disturbance phase", the control means 4 controls the waveform storage / reproduction means 1 based on the waveform read information from the waveform read information calculation means 5, and the waveform storage / reproduction means 1 operates according to the control. Of the stored waveforms, only the cutout pulse waveform (waveform in which the pulse center is shortened and the pulse width is shortened) to be used as an interfering wave is continuously output at the cycle of the cutout pulse width.

Here, the cut-out waveform used as an interfering wave is of one type (pulse width τ '= kτ), and this is continuously and repeatedly reproduced (waveform reading period PRI≈τ' is constant).

According to this embodiment, according to the configuration of the present invention, the radar chirp wave is stored in the waveform storing / reproducing means 1
At the same time, the pulse rise and fall positions of the radar chirp wave are detected by the waveform detection means 2, and the waveform read start position and end position for cutting out the pulse based on the detected information are detected by the waveform read information calculation means 5. When the calculated pulse is repeatedly reproduced as a continuous pulse train by repeating the cut-out pulse and sent out as an interfering wave, the control means 4 obtains the central portion of the pulse with respect to this continuously reproduced pulse, and an arbitrary width from the center A modulator for a jammer capable of varying the equivalent jamming power and the jamming duty can be provided by having a modulation function of performing clipping and repeatedly performing shorter than the received pulse width.

In the above-described embodiment, the case where one kind of waveform is repeatedly reproduced has been described. However, cut-out waveforms having the same original waveform but different pulse widths are prepared, and the longest pulse width τ'in order. Reading and reproduction can be performed. In this case, the waveform read cycle PRI≈τ ′
Also changes. The read out cutout interference wave is subjected to Doppler modulation by the Doppler modulation means 3 and then output as an interference wave.

According to this embodiment, it is possible to send out an interfering wave whose repetition cycle is sequentially shortened with the passage of time. Here, the waveform read information calculation means 5 will be described in detail. In the conventional method, basically, the waveform written in the waveform storage circuit is simply read as it is. However, in the present invention, only the waveform used as the interfering wave is selected from the written waveforms, and the selected waveform is further selected. Reading is performed so that the pulse width τ ′ = kτ and the waveform center coincides with the waveform center of the original waveform.

Therefore, the waveform read-out information calculating means 5 calculates the start / end positions of the stored waveform, and then stores / reproduces the waveform whose pulse width τ ′ = kτ and whose pulse center coincides with the original pulse. Information on which position (address) of the means 1 is stored is calculated as the waveform reading start / end position. Since the cutout pulse width τ ′ is also the readout cycle of the cutout pulse waveform, it is given to the control means 4 together with the waveform read start / end position information.

Here, in the case of one kind of pulse, the cutout rate k is one kind, and in the case of a plurality of kinds of pulses, the cutout rate k is changed according to the number of read repetitions (pulse width is There are multiple to reduce). Therefore, the information calculated / output by the waveform read information calculation means 5 is of one kind or plural kinds.

FIG. 7 is a first explanatory diagram of the interference modulation method of the present invention. In the case of this method, the pulse width τ of the received reception radar chirp waveform is fixed to the pulse width of (1/2) τ, and as shown in the figure, the waveform of the amplitude A with the chirp bandwidth B / 2 is continuously used as the interfering wave. And send. Here, the case where the interfering wave is synchronized with the pulse repetition frequency of the radar is shown. Compared to the conventional example, the number of bands of interfering waves displayed on the enemy radar scope is doubled, and the rate of hiding the radar target is increased. Here, the targets □ and Δ are hidden by the pseudo target due to the interfering wave.

FIG. 10 is a fourth explanatory diagram of the interference modulation method of the present invention. In the case of this method, the pulse width τ of the received received radar chirp waveform is sequentially (1/2) τ (1 /
n) Bandwidth B / n is changed up to τ before transmission. Then, as shown in the figure, the waveform of the amplitude A with the chirp bandwidth B / 2 is continuously transmitted as an interfering wave. Here, the case where the interfering wave is synchronized with the pulse repetition frequency of the radar is shown. Compared with the conventional example, the number of bands of the interfering wave displayed on the enemy radar scope is doubled or more, and the ratio of hiding the radar target increases. Here, the targets □, Δ, and ◇ are hidden by the pseudo targets due to the interfering waves.

FIG. 2 is a block diagram showing a first embodiment of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals. The difference from the configuration shown in FIG.
The point is that a waveform synthesizing / forming means 10 for performing waveform synthesis and waveform formation is provided between the reproducing means 1 and the Doppler modulation means 3. The waveform synthesizing / forming means 10 is the modulation calculating means 11
And a waveform delay means 12 and a waveform synthesis means 13.

The output of the waveform storing / reproducing means 1 enters the modulation calculating means 11, and the output of the modulation calculating means 11 enters the waveform delay means 12 and the waveform synthesizing means 13. Other configurations are the same as those in FIG. The operation of the apparatus thus configured will be described below.

In the "waveform acquisition phase", when the radar signal to be disturbed is input to the jammer, the waveform storage / reproduction means 1 unconditionally stores the signal waveform. At the same time, the signal waveform enters the waveform detecting means 2, and the waveform detecting means 2 detects the presence or absence of a pulse by detecting the rising and falling edges of the waveform as in the conventional case, and the waveform read information calculating means 5
Give to.

The waveform read information calculating means 5 stores / reproduces the waveform from the pulse detection information and the pulse superposition rate information (a parameter indicating how much of two pulses are superposed, which is given by the control means 4). Information necessary for reading the waveform from the means 1 (read start / end position, read cycle, pulse width, etc.) is calculated and given to the control means 4.

In the "jamming phase", the control means 4 controls the waveform storing / reproducing means 1 based on the waveform read information, and the waveform storing / reproducing means 1 controls based on the control.
Of the stored waveforms, only the pulse waveform used as an interfering wave (the original waveform of the pulse center and width) is continuously reproduced and output.

This output signal is used by the waveform synthesizing / forming means 10
To enter. Then, first, amplitude modulation is performed by the modulation calculation means 11 so as to have a trapezoidal slope. The modulated signal is branched into two, and only one of them is delayed by the waveform delaying means 12, and then the two waveforms are combined (added) by the waveform combining means 13. Here, the waveform delay means 12 causes the slopes of the trapezoidal modulated pulses to overlap each other.

Here, if pulse superposition rate α = width of superposed portion / pulse width pulse width = τ, the delay time Td of two waves is Td = (1−α) τ. The waveform reading period PRI from the waveform storing / reproducing means 1 is PRI≈2Td.

Here, the composite waveform used as the interfering wave may be of one kind or of plural kinds. In the case of one type of composite waveform, this is continuously and repeatedly reproduced. According to this embodiment, the waveform synthesizing / forming means 10 performs trapezoidal / triangular waveform shaping, and the slopes of the waveforms are overlapped so that the repetition interval is shorter than the pulse width. Then, the interference wave can be transmitted.

The composite waveform used as the interfering wave is
It is also possible to sequentially read out a plurality of types of composite waveforms having different superimposition rates α, from the one having a smaller superimposition rate, and perform reproduction. In this case, the waveform read cycle PRI≈
2Td also changes.

According to this embodiment, it is possible to send out an interfering wave having an increased slope superposition time earlier with time. Next, the waveform read information calculation means 5 and the waveform synthesis / formation means 10 in the form of FIG. 2 will be described. In the first embodiment, the superimposing rate α is constant, and in the latter, the superimposing rate α changes (increases the superimposing rate) according to the number of read repetitions.
The waveform read-out information output by the waveform read-out information calculation means 5 is one kind in the former, but plural kinds in the latter.

When the waveform synthesizing / forming means 10 receives the pulse width τ calculated by the waveform read information calculating means 5 and the pulse superimposition rate α from the control means 4, it generates a trapezoidal modulation coefficient in accordance therewith, Amplitude modulation processing is performed on the waveform signal input from the waveform storage / reproduction means 1. The modulated signal is 2
After branching into two parts and applying a time delay of Td = (1−α) τ only to one of them, the waveforms of the two signals are combined. In the former case, since the superposition rate α is one, the modulation coefficient and the time delay Td are one.
It is a type and is constant regardless of the number of times of reading.

In the latter case, the superimposition rate α changes (increases the superimposition rate) according to the number of read repetitions, so that there are a plurality of modulation coefficients and delay times Td, which are sequentially changed according to the number of read times. Go.

FIG. 8 is a second explanatory diagram of the interference modulation method of the present invention. In the case of this method, the pulse width τ of the received radar chirp waveform is made to overlap each other (overlap C).
An overlapping portion is provided, and repetitive interfering waves of amplitude A and chirp bandwidth B are transmitted. Again, this is the case when the interfering wave is synchronized with the radar pulse repetition frequency,
Compared with the conventional technique, the number of interference wave bands displayed on the enemy radar scope is increased by the amount of overlap, so that the ratio of hiding the radar target is increased. In the case of the figure, □ and part of Δ are hidden by the pseudo target.

FIG. 11 is a fifth explanatory diagram of the interference modulation method of the present invention. In the case of this method, the interfering wave is transmitted while the pulse widths τ of the received radar chirp waveforms are superposed on each other and the superimposition rate is sequentially changed.
Also in this case, the interference wave is synchronized with the pulse repetition frequency of the radar. According to this, since the number of the interference wave bands displayed on the enemy radar scope is increased by the overlap, the ratio of hiding the radar target is increased. In the figure, □, △, and part of ◇ are hidden by the pseudo target.

FIG. 3 is a block diagram showing a second embodiment of the present invention. The same parts as those in FIG. 2 are designated by the same reference numerals. In this embodiment, the internal structure of the waveform synthesizing / forming means 10 is different from that in FIG.
In the waveform synthesizing / forming means 10, 14 is an N-1 stage waveform delay means. Reference numeral 15 is a waveform synthesizing means for synthesizing the waveforms of the respective outputs of these waveform delay means 14, and the output thereof is inputted to the Doppler modulation means 3. The operation of the apparatus thus configured will be described below.

In the "waveform acquisition phase", when the radar signal to be disturbed is input to the jammer, the waveform storage / reproduction means 1 unconditionally stores the input signal waveform.
At the same time, the radar chirp wave is also input to the waveform detection means 2,
As in the conventional case, the waveform detecting means 2 detects the presence / absence of a pulse by detecting the rising edge and the falling edge of the waveform, and supplies it to the waveform read information calculating means 5.

The waveform read information calculation means 5 uses the pulse detection information and the pulse superposition number information (parameter indicating how many pulses are to be superposed), which is necessary for reading the waveform from the waveform storage / reproduction means 1 (readout). The start / end position, the read cycle, the pulse width, etc.) are calculated and given to the control means 4.

In the "jamming" phase, the control means 4
Is the waveform storage / reproduction means 1 based on the waveform read information.
Based on the control, the waveform storage / reproduction means 1 continuously reproduces and outputs the pulse waveform (the original waveform of the pulse center and the width) used as an interfering wave among the stored waveforms. To do.

This output signal is used by the waveform synthesizing / forming means 10
, And can be delayed by N stages. N is the number of superposed pulses, and when the pulse width is τ, the delay time Td per stage is Td = τ / N. The waveform reading period PRI from the waveform storing / reproducing means 1 is PRI≈τ. Then, the N outputs from the respective waveform delay means 14 are the waveform synthesizing means 15
Waveforms are synthesized by the waveform synthesis / formation means 10 (specifically, the waveform synthesis means 15) and output.

Here, when the number N of waveforms to be synthesized as an interfering wave is fixed, there is one type of synthetic waveform output from the waveform synthesizing / forming means 10, and this is continuously repeated to reproduce the interfering wave. .

According to this embodiment, it is possible to continuously transmit as an interfering wave. Next, the waveform synthesis number N to be synthesized as an interfering wave can be increased with the number of times of waveform readout. In this case, for the synthesized waveform having the waveform synthesis number N,
The data can be sequentially read and reproduced. At this time, the waveform read cycle PRI≈τ is constant.

According to this embodiment, it is possible to transmit an interfering wave in which the number N of simultaneous reproductions is increased as the time of continuous reproduction elapses. Next, the waveform read information calculation means 5
The waveform synthesizing / forming means 10 will be described. The waveform read information calculation means 5 has a function of calculating the delay time Td = τ / N and the pulse width τ required by the waveform synthesizing / forming means 10, in addition to the calculation of the stored waveform start / end positions. These pieces of information are given to the control means 4 as waveform read information.

Here, in the former case, the superposition number N is constant, and in the latter case, the superposition number N changes (increases the superposition number) according to the number of read repetitions. The waveform read information output by 5 is one kind in the former case, but is plural kinds in the latter case.

The waveform synthesizing / forming means 10 has the pulse width τ calculated by the waveform read information calculating means 5 and the superimposed pulse width τ / N.
From the control means 4 to form N stages of delay time (each delay time Td is Td = (1−α) τ) and N addition / synthesis systems from each delay element.
Therefore, in the former case, the superposition number N is constant, so the operation of the delay system / addition / synthesis system is constant regardless of the read repetition number, and in the latter case, the superposition number N is changed according to the read repetition number (superposition number). In order to increase the number), the operations of the delay system and the adding and combining system are sequentially changed according to the number of times of reading.

FIG. 9 is a third explanatory diagram of the interference modulation method of the present invention. The received radar chirp waveform (pulse width τ, chirp bandwidth B) is continuously transmitted as a delayed combined waveform with the pulse width unchanged. In the figure, the case where N = 2 is shown. The disturbing waveform is a continuous repetition of two waveforms as shown. In this case, the frequency is the chirp bandwidth B, and the amplitude is a superposition of two A / 2. Also in this case, the interference wave is synchronized with the pulse repetition frequency of the radar.

According to this embodiment, the number of interference wave bands displayed on the enemy radar scope is doubled as compared with the conventional example, and the radar targets of □ and Δ can be hidden. . FIG. 12 is a sixth explanatory diagram of the interference modulation method of the present invention. The received radar chirp waveform (pulse width τ, chirp bandwidth B) is continuously transmitted as a delayed combined waveform with the pulse width unchanged. In the figure, the case where N = 2 is shown. The disturbing waveform is a continuous repetition of two waveforms as shown. In this case, the frequency is the chirp bandwidth B
Therefore, the amplitude is a combination of two A / 2. The cycle becomes shorter with the passage of time.
Also in this case, the interference wave is synchronized with the pulse repetition frequency of the radar.

According to this embodiment, the number of bands of interfering waves displayed on the enemy radar scope is more than doubled as compared with the conventional example, and the radar targets of □ and Δ are hidden. Can be done, and the rate of hiding the radar target is further increased.

13 and 14 are block diagrams showing a first concrete example of the embodiment of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals. In this figure, the first
In the configuration of (1), since the cutout rate k is one type, only one system of the dotted line portion in the waveform read information calculation circuit 5 is used. In the case of the second configuration, there are a plurality of cutout rates k. A plurality of dotted lines in the circuit 5 are used in parallel.

The received signal is A / D converted by the A / D converter 1a.
Semiconductor memory 1 in D-converted waveform storage / reproduction circuit 1
b and the amplitude detector 2a in the waveform detection circuit 2 are both branched. In the reception signal acquisition period, the control circuit 4 sends a write start pulse to the memory control counter 1c in the waveform storage / reproduction circuit 1 to start writing a signal to the memory.

At the same time, the memory control timing management counter 5a in the waveform read information calculation circuit 5 also starts its operation and performs the same operation as the memory control counter 1c in the waveform storage / reproduction circuit 1. When the signal acquisition to the semiconductor memory 1b is completed, the memory control timing management counter 5a in the waveform read information calculation circuit 5 generates a write completion notification and notifies the control circuit 4.

Simultaneously with the operation of the memory control timing management counter 5a, the received signal is amplitude-detected by the amplitude detector 2a, and the subsequent comparator 2b compares it with the threshold value. When there is a received signal that exceeds the threshold value, the pulse detection result gate signal is turned on to notify the waveform read information calculation circuit 5 that a pulse has been detected.

In the waveform read information calculation circuit 5, the memory control timing management counter value is latched by the waveform start / end address latch 5b at the change point of the pulse detection result gate signal and calculated as the waveform write start / end address.

Next, the waveform writing start address and the end address are added and divided by the bit shift 5c to calculate the center address of the waveform. Similarly, the waveform start address is subtracted from the waveform end address by the subtracter 5d to calculate the pulse width τ and latch it.

Further, the pulse width τ is calculated by multiplying the pulse width τ by the cutout rate k in the multiplier 5e, and the pulse width of kτ is calculated.
The I value is latched by the latch 5f. Here, the cutout rate k is preset by the control circuit 4. Here, the cutout rate k to be output may be one kind or plural kinds.

The adder 5g adds the waveform center address and the kτ pulse width to obtain the waveform read end address, and the subtracter 5h subtracts kτ from the waveform center address to obtain the waveform read start address. These waveform read start / end addresses, pulse width τ, and PRI value are P as waveform read information every time pulse detection is performed.
It is latched by the RI value latch 5f and notified to the control circuit 4, and the control circuit 4 stores all the detected pulse. The waveform read information calculation circuit 5 does not need to be executed by independent hardware, and in that case, it may be realized by software in the configuration of the control circuit 4.

After receiving the waveform writing completion notification, the control circuit 4 selects the pulse waveform to be disturbed with reference to the pulse width τ, etc., and selects only one (or a plurality) of waveform reading start / end addresses of the selected waveform. The waveform storage / reproduction circuit 1 is notified, and the waveform storage / reproduction circuit 1 stores these in the memories 1d and 1e. Here, the selection information of the signal to be selected is previously input to the control circuit 4 as the waveform control information.

The control circuit 4 sends a read start pulse to the waveform storage / reproduction circuit in the period of sending the interfering wave. The read start pulse is generated a plurality of times in the cycle of the PRI value because the disturbing wave is repeatedly transmitted.
If there are multiple types of repetitive pulses, PRI once
Update the value.

Upon receiving the read start pulse, the memory control counter 1c of the waveform storage / reproduction circuit 1 generates an address according to the read start / end address (in the case of a plurality, the read start / end address is updated in the PRI cycle). Then, the stored waveforms are sequentially read from the semiconductor memory 1b, converted into an analog signal by the D / A converter 1f, and then subjected to Doppler modulation by the Doppler modulation circuit 3 and transmitted.

15 and 16 are block diagrams showing a second specific example of the embodiment of the present invention. 13 and 14
The same parts as those shown in FIG. in this case,
There are cases where the superimposition rate α is one type (the former) and plural cases (the latter). If the superimposition rate α is one type, only one system is used for the dotted line portion in the waveform read information calculation circuit 5. If there are multiple α, there are multiple superimposition rates, so the dotted line portion in the waveform read information calculation circuit 5 is used. Uses multiple in parallel.

The received signal is A / D converted by the A / D converter 1a, as in the case of FIG. 13 and FIG. 14, and when the received signal acquisition period starts, signal writing to the semiconductor memory 1b is started. At the same time, the memory control timing management counter 5a in the waveform read information calculation circuit 5 also starts operating, and the memory control counter 1c in the waveform storage / reproduction circuit 1 is started.
Perform the same operation as.

When the signal acquisition into the semiconductor memory 1b is completed, the control circuit 4 is notified. Further, the received signal is amplitude-detected by the amplitude detector 2a of the waveform detection circuit 2 and is compared with the threshold value by the comparator 2b to notify the waveform read-out information calculation circuit 5 that the received signal is detected.

In the waveform read information calculation circuit 5, the memory control timing management counter 5a is latched by the waveform start / end address latch 5b at the change point of the pulse detection result gate signal, and the pulse is the semiconductor in the waveform storage / reproduction circuit 1. Which address in the memory 1b is written is stored and notified to the control circuit 4 as a waveform start / end address.

Next, the waveform start address is subtracted from the waveform end address by the subtracter 5d to calculate the pulse width τ and latch it. At the same time, τ is multiplied by the pulse superposition rate α set by the control circuit 4 by the multiplier 5i, the pulse width τ is subtracted, and the delay time Td =
(1-α) τ is calculated by the calculator 5j. Here, the superimposition rate α is preset by the control circuit 4. In the latter case, a plurality of superimposition rates α are set.

The pulse width τ and the delay time Td are latched in the delay time latch 5k every time a pulse is detected and notified to the control circuit 4, and the control circuit 4 stores all the detected pulse. deep. The waveform read information calculation circuit 5 does not need to be executed by independent hardware, and in that case, it may be realized by software in the configuration of the control circuit 4.

The control circuit 4, after receiving the waveform writing completion notice, changes the pulse waveform to be disturbed to the pulse width τ.
And the like, and notifies the waveform storage / reproduction circuit 1 of the read start / end addresses of the disturbance target waveform. In addition, the pulse width τ, the superimposition rate α, and the delay time are notified to the waveform synthesis / formation circuit 10 by one type (in the latter case, a plurality of types). Each circuit stores these pieces of information in the memory. Here, the selection information of the signal to be selected is previously input to the control circuit 4 as the waveform control information.

The modulation coefficient memory 10a in the waveform synthesizing / forming circuit 10 stores modulation coefficients relating to various pulse widths for each superposition rate α, and the given pulse width τ,
A modulation coefficient according to the superimposition rate α is set in the modulation multiplier 10b.

The control circuit 4 sends a read start pulse to the waveform storage / reproduction circuit 1 when the interfering wave is transmitted.
In addition, the same pulse is used as the write start pulse for waveform synthesis /
It is given to the memory control counter 10c in the forming circuit 10.
The memory control counter 1c of the waveform storage / reproduction circuit 1 generates an address or the like according to the read start / end address,
The stored waveforms are read out in sequence. The output from the waveform storage / reproduction circuit 1 is input to the waveform synthesis / formation circuit 10, in which trapezoidal amplitude modulation is performed and branched into two.

One of the branched signals is input to a delay memory (eg, FIFO) 10g and is output with a delay time of Td from the input by a read signal provided by the memory control counter 10c. The output of the delay memory 10g and the amplitude modulation signal are added by the adder 10h, the amplitude value is halved by bit shift or the like, and then the D / A converter 1f.
Is D / A converted by, and the Doppler modulation circuit 3 performs Doppler modulation for transmission.

Here, after reading one waveform,
The time PRI until the reading of the next waveform is 2Td (in the latter case, 2Td changes with time), and the control circuit 4 generates the reading start pulse in the cycle of 2Td during the period of transmitting the interfering wave. Memory control counters 1c and 10 in the waveform storage / reproduction circuit 1 and the waveform synthesis / formation circuit 10
The waveform is output to the waveform storage / reproduction circuit 1 at a cycle of 2Td, and the above operation is repeated.

17 and 18 are block diagrams showing a third specific example of the embodiment of the present invention. 13 and 1
4, FIG. 15, and FIG. 16 are the same as those shown in FIG. In this embodiment, there are one type of superposed pulse N (the former) and a plurality of superposed pulses N (the latter).
In the former case, only one system of the dotted line part in the waveform read information calculation circuit 5 is used, and in the latter case, a plurality of dotted line parts in the waveform read information calculation circuit 5 are used in parallel.

The received signal is A / D converted by the A / D converter 1a as in the case of the above-described embodiment, and when the received signal fetch period starts, signal writing to the semiconductor memory 1b is started. At the same time, the memory control timing management counter 5a in the waveform read information calculation circuit 5 also starts operating, and the memory control counter 1c in the waveform storage / reproduction circuit 1 is started.
Perform the same operation as.

When the signal acquisition into the semiconductor memory 1b is completed, the control circuit 4 is notified. Further, the received signal is amplitude-detected by the amplitude detector 2a in the waveform detection circuit 2, compared with the threshold value by the comparator 2b, and the waveform read-out information calculation circuit 5 is notified that the received signal is detected.

In the waveform read information calculation circuit 5, the memory control timing management counter value is latched by the waveform start / end address latch 5b at the change point of the pulse detection result gate signal, and the pulse is stored in the waveform storage / reproduction circuit 1 in the memory. In which address is written, the control circuit 4 is notified as a waveform start / end address.

Next, the subtractor 5d performs an operation for subtracting the waveform start address from the waveform end address, and the subtraction result is set as the pulse width τ and latched in the pulse width latch 5l. At the same time, the superimposed pulse N set by the control circuit 4 is multiplied by the multiplier 5m. Then, the delay time Td = τ / N corresponding to the delay amount at the time of waveform synthesis is calculated and latched by the latch 5n. Here, the superposition pulse number N is preset by the control circuit 4. In the latter case, a plurality of superposition pulses N are set.

The values of the pulse width τ and the delay time Td = τN are latched every time pulse detection is performed, and are notified to the control circuit 4, and the control circuit 4 stores all the detected pulse amounts. . The waveform read information calculation circuit 5
Need not be executed by independent hardware, in which case it can be realized by software in the configuration of the control circuit.

After receiving the waveform write completion notice, the control circuit 4 changes the pulse waveform to be disturbed to the pulse width τ.
And the like, and informs the waveform storage / reproduction circuit 1 of the read start / end addresses of the waveform to be disturbed, and the delay time T
One type of d = τN and the pulse width τ is notified to the waveform synthesis / formation circuit 10 (in the latter case, a plurality of types are notified). Each circuit stores these pieces of information in the memory. Here, the selection information of the signal to be selected is previously input to the control circuit 4 as the waveform control information.

The control circuit 4 sends a read start pulse to the waveform storage / reproduction circuit 1 when the interfering wave is transmitted.
In addition, the same pulse is used as the write start pulse for waveform synthesis /
It is given to the memory control counter 10c in the forming circuit 10.

The memory control counter 1c of the waveform storage / reproduction circuit 1 generates an address or the like according to the read start / end address, and sequentially reads the stored waveform from the semiconductor memory 1b. The output from the waveform storage / reproduction circuit 1 is directly used for the delay memory (FIFO) in the waveform synthesis / formation circuit 10.
Etc.) Input to 10i for τ, and memory control counter 10c
According to the read signal given by, the signal is output with a delay time of Td from the input and input to the next delay memory 10i.

The output signal from the waveform storage / reproduction circuit 1 and the output signal from each of the delay memories 10i are sequentially added to the adder 1.
0j is added, the multiplier 10k sets the amplitude value to 1 / N, the D / A converter 1f performs D / A conversion, the Doppler modulation circuit 3 receives the Doppler modulation, and the signal is transmitted. .

The time PRI from the reading of one waveform to the reading of the next waveform is τ, and the control circuit 4
Generates a read start pulse at a period of τ during the period of transmitting an interfering wave, and combines the waveform with the waveform storage / reproduction circuit 1
The waveform is given to the memory control counter 10c in the forming circuit 10, and the waveform is output from the waveform storing / reproducing circuit 1 at a cycle of τ,
The above operation is repeated.

19 and 20 are block diagrams showing a fourth specific example of the embodiment of the present invention. In this case, the configuration in the case where the number of delay memories in the embodiment examples shown in FIGS. 17 and 18 is reduced is shown. FIG. 21 is a time chart showing the operation.

The received signal is A / D converted by the A / D converter 1a in the same manner as in the examples shown in FIGS. 13 and 14, and when the received signal fetch period starts, signal writing to the semiconductor memory 1b is started. At the same time, the waveform read information calculation circuit 5
The memory control timing management counter 5a therein also starts operation, and the memory control counter 1c in the waveform storage / reproduction circuit
Perform the same operation as.

When the signal acquisition to the semiconductor memory 1b is completed, the control circuit 4 is notified. Further, the received signal is amplitude-detected by the amplitude detector 2a in the waveform detection circuit 2, the threshold value is compared with the comparator 2b, and if there is a received signal, the waveform read-out information calculation circuit 5 is notified of the detection. To do.

In the waveform read information calculation circuit 5, the count value of the memory control timing management counter 5a is latched by the waveform start / end address latch 5b at the change point of the pulse detection result gate signal, and the pulse is stored in the waveform storage / reproduction circuit 1. The address in the internal memory where the data is written is stored and notified to the control circuit 4 as the waveform start / end address.

Next, the waveform start address is subtracted from the waveform end address by the subtracter 5d to calculate and latch the pulse width τ. Further, the 1 / N pulse width τ / N is calculated by the multiplier 5m according to the reciprocal 1 / N value of the superimposed pulse N instructed by the control circuit 4, and the delay time Td is latched in the delay time latch 5n.

These pulse width τ and delay time Td = τ / N
The value of is latched every time pulse detection is performed, and is notified to the control circuit 4, and the control circuit 4 stores all the detected pulse. The waveform read information calculation circuit 5 does not have to be executed by hardware, and may be realized by software in the control circuit 4.

After receiving the waveform write completion notice, the control circuit 4 sets the pulse width τ for the pulse waveform to be disturbed.
And the like, and informs the waveform storage / reproduction circuit 1 of the read start / end addresses of the waveform to be disturbed, and the delay time T
The waveform synthesis / formation circuit 10 is notified of d = τ / N, the number of pulse superpositions N, and the pulse width τ.

Each circuit latches these pieces of information. Here, the selection information of the signal to be selected is previously input to the control circuit 4 as the waveform control information. Next, the control circuit 4 uses the read start pulse as the waveform storage / reproduction circuit 1 and the same pulse as the write start pulse as the memory control counter 10c of the waveform synthesis / formation circuit 10.
Give to. The memory control counter 1c of the waveform storage / reproduction circuit 1 generates an address or the like according to the read start / end address and sequentially reads the stored waveform.

The output from the waveform storage / reproduction circuit 1 is added to the output value from the selection circuit 3 in the waveform synthesis / formation circuit 10 and then stored in the memory A or B via the selection circuit 1. . The selection circuit 3 selects 0 only during the first τ / N period, and selects the output value of the selection circuit 2 during the remaining period (τ / T to τ).

The selection circuit 1 alternately selects the memories A and B for each delay time Td = τ / N, and the selection circuit 2 selects the selection circuit 1
And make the opposite selection. By performing the above operation, when the output of all the data from the memory for waveform control is completed, the memory A or B of the waveform synthesis / formation circuit 10 stores the synthesized waveform having the pulse width τ / N. ing.

The control circuit 4 sends a read start pulse to the waveform synthesizing / forming circuit 10 when the interfering wave is sent. The memory control counter 10c in the waveform synthesizing / forming circuit generates an address of 1 / N pulse width and the like, reads sequentially stored waveforms, and multiplies the amplitude to 1 / N, and then performs D / A conversion. The device 1f performs D / A conversion, and the Doppler modulation circuit 3 performs Doppler modulation for transmission.

Next, the timing shown in FIG. 21 will be described. In the read mode, data D01 to D12 corresponding to the address are sequentially read from the memory of the waveform storage / reproduction circuit 1. The output from the waveform storage / reproduction circuit 1 is
After being added to the output value (initially 0) from the selection circuit 3 in the waveform synthesis / formation circuit 10, it is stored in the memory A or B via the selection circuit 1. That is, the selection circuit 3 selects 0 only during the first τ / N period, and always selects the output of the selection circuit 2 during the remaining period.

First, as shown in the figure, the selection circuit 1 selects the memory A side, the selection circuit 2 selects the memory B side, and the selection circuit 3 selects 0. The selection circuit 1 alternately selects the memory A and the memory B for each delay time Td. on the other hand,
The selection circuit 2 alternately selects the memory B and the memory A.

As shown in the figure, in the first step, the memory A writes the data D01, D02, D03.
On the other hand, the memory B enters the read mode and outputs nothing. In the next step, the memory A enters the read mode and the data is read. The read data enters the selection circuit 2. Since the selection circuit 2 alternately selects the memories A and B, the data in the memory B is D01, D02,
D03, D05, D06 are added.
That is, D01 + D04 is stored in the address A01, D02 + D05 is stored in the address A02, and D03 + D06 is stored in the address A03. This data is transmitted from memory B to memory A as shown. Therefore, in the next step, the contents of the data D07 to D09 are newly added to the contents of the memory B in the write mode of the memory A.

Then, in the final step, the contents of the memory A are given to the memory B via the selection circuit 1, and the memory B receives the address A01 at D01 + D04 + D07 + D1.
0 is stored, and at address A02, D02 + D05 +
D08 + D11 is stored, and D0 is stored in the address A03.
3 + D06 + D09 + D12 is stored. In this way, when all the data from the waveform storage / reproduction circuit has been output, the memory A and the memory B of the waveform synthesis / formation circuit are
Will store a composite waveform with a pulse width of τ / N.

As described above, according to the present invention, the equivalent jamming power (peak power value after pulse compression) and the jamming duty can be varied by the jammer modulator of the invention. When disturbing the chirp radar, the area where the disturbing wave is displayed on the other radar scope can be increased, so the probability of detecting the radar target can be reduced and the disturbing effect can be improved. Is possible. Here, the input signal is the chirp wave of the radar, but the same effect can be obtained with a radar pulse having a phase code code.

Further, in the above-mentioned embodiment, the Doppler modulation means is used for the modulation at the final stage, but it is not necessary to apply the Doppler modulation to the target that does not move, and the output of the waveform storage / reproduction means is used. Can be directly transmitted as an interfering wave.

[0130]

As described above in detail, (1) According to the first invention, the waveform storing / reproducing means for receiving and storing the radar chirp wave, and the waveform detecting means for detecting the pulse waveform. , A waveform read-out information calculation means for calculating a waveform read-out position / reproduction time and a control means for controlling each of the above circuits. The radar chirp wave is stored in the waveform storage / reproduction means at the same time as the radar chirp. The rising and falling positions of the pulse of the wave are detected by the waveform detecting means, and the waveform reading information calculating means calculates and reads the waveform reading start position and the ending position for cutting out the pulse based on this detection information, and the cut-out pulse is obtained. In the case where the pulse is repeatedly reproduced as a continuous pulse train and is transmitted as an interfering wave, the control means controls the pulse to be continuously reproduced among the pulses. The radar chirp wave is memorized by the waveform storing / reproducing means at the same time as the center of the radar is cut out in an arbitrary width from the center and is repeatedly performed shorter than the received pulse width. The falling position is detected by the waveform detecting means, the waveform read start position and the end position for cutting out the pulse based on the detected information are calculated by the waveform read information calculating means, and the cut out pulse is repeatedly reproduced as a continuous pulse train, In the case of transmitting as an interfering wave, the control means obtains the central part of the pulse for this continuously reproduced pulse, cuts it out from the center with an arbitrary width, and has a modulation function of repeating repeatedly shorter than the received pulse width. This makes it possible to change the equivalent disturbance power and the disturbance duty. It is possible to provide a vessel.

(2) In this case, the waveform storage /
In the circuit in which the waveform synthesizing / forming means for synthesizing / forming the waveform is added after the reproducing means, the control means fetches the received radar chirp wave into the waveform storing / reproducing means,
The leading edge and the trailing edge of the pulse are amplitude-modulated in a slope shape, and the waveform synthesis / formation means forms a trapezoidal / triangular waveform to superimpose the slope portion of the waveform so that the amplitude becomes constant. The waveform synthesizing / shaping means performs waveform shaping in a trapezoidal / triangular manner by performing waveform synthesis on the waveform and continuously reproducing it so that the repetition interval is shorter than the pulse width and transmitting it as an interfering wave. By superimposing the slope of, the interfering wave can be transmitted by continuously reproducing so that the repetition interval is shorter than the pulse width.

(3) Further, the waveform synthesis / formation means is
1 / N to N / N of pulse width of received radar chirp wave
The pulse waveform is delayed for each time and repeatedly played,
Since the N waveforms being reproduced at the same time are superimposed and synthesized by the waveform synthesizing / forming means so as to have a constant amplitude, and have a modulation function of continuously transmitting as an interfering wave, it is possible to continuously transmit as an interfering wave. .

(4) Further, the control means shortens the pulse width which is cut out from the pulse and continuously reproduced, with the lapse of time, and makes the pulse repetition period faster,
It is possible to send out an interfering wave whose repetition cycle is sequentially shortened with the passage of time.

(5) Further, the control means makes the slopes of the leading edge and the trailing edge of the pulse gentle as the time of continuous reproduction elapses to increase the overlap time of the slope portion and accelerate the pulse repetition period. As a result, it becomes possible to send out an interfering wave with an increased slope superposition time earlier with time.

(6) In addition, the control means increases the number N of simultaneous reproductions with the elapse of continuous reproduction time, so as to send out the interference wave with the number N of simultaneous reproductions increased with the elapse of continuous reproduction time. It becomes possible to do.

(7) According to the second invention, the waveform storing / reproducing means for receiving and storing the radar chirp wave, the waveform detecting means for detecting the pulse waveform, the Doppler modulating means for performing the Doppler modulation, and the waveform Waveform read information calculation means for calculating the read position / reproduction time and control means for controlling each of the above circuits. The radar chirp wave is stored in the waveform storage / reproduction means and at the same time the radar chirp wave is stored. The pulse rising and falling positions are detected by the waveform detecting means, the waveform reading start position and the end position for cutting out the pulse are calculated based on this detection information, and read,
In the case where the cut-out pulse is repeatedly reproduced as a continuous pulse train, and the Doppler modulation unit performs Doppler modulation to send out as an interfering wave, the control unit obtains a central portion of the pulse with respect to the continuously reproduced pulse. The radar chirp wave is stored in the waveform storing / reproducing means at the same time as the radar chirp wave is stored by the waveform storing / reproducing means by simultaneously cutting out from the center with an arbitrary width and repeatedly performing shorter than the received pulse width. Detected by the waveform detection means, based on this detection information, the waveform read start position and end position for cutting out the pulse are calculated by the waveform read information calculation means, and the cut out pulse is repeatedly reproduced as a continuous pulse train and subjected to Doppler modulation. In the case of transmitting as an interfering wave by the The equivalent jamming power and jamming duty can be varied by finding the center of the pulse to be continuously reproduced, cutting it out from the center with an arbitrary width, and having a modulation function that repeats shorter than the received pulse width. It is possible to provide a modulator for a jammer.

As described above, according to the present invention, it is possible to provide a modulator for an interfering device in which the equivalent interfering power and the interfering duty can be varied.

[Brief description of drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a block diagram showing a first exemplary embodiment of the present invention.

FIG. 3 is a block diagram showing a second exemplary embodiment of the present invention.

FIG. 4 is an explanatory diagram of an interfering wave and a radar echo timing in a partner radar.

FIG. 5 is an explanatory diagram of a radar reception level.

FIG. 6 is an explanatory diagram of a conventional interference modulation method.

FIG. 7 is a first explanatory diagram of the interference modulation method of the present invention.

FIG. 8 is a second explanatory diagram of the interference modulation method of the present invention.

FIG. 9 is a third explanatory diagram of the interference modulation method of the present invention.

FIG. 10 is a fourth explanatory diagram of the jamming system of the present invention.

FIG. 11 is a fifth explanatory diagram of the interference modulation method of the present invention.

FIG. 12 is a sixth explanatory diagram of the interference modulation method of the present invention.

FIG. 13 is a block diagram showing a first specific example of the embodiment of the present invention.

FIG. 14 is a block diagram showing a first specific example of the embodiment of the present invention.

FIG. 15 is a block diagram showing a second specific example of the embodiment of the present invention.

FIG. 16 is a block diagram showing a second specific example of the embodiment of the present invention.

FIG. 17 is a block diagram showing a third specific example of the embodiment of the present invention.

FIG. 18 is a block diagram showing a third exemplary embodiment of the exemplary embodiment of the present invention.

FIG. 19 is a block diagram showing a fourth exemplary embodiment of the exemplary embodiment of the present invention.

FIG. 20 is a block diagram showing a fourth exemplary embodiment of the exemplary embodiment of the present invention.

FIG. 21 is an operation explanatory diagram of the waveform synthesizing / forming circuit.

FIG. 22 is a block diagram showing a configuration example of a conventional device.

[Explanation of symbols]

1 Waveform storage / reproduction means 2 Waveform detection means 3 Doppler modulation means 4 Control means 5 Waveform readout information calculation means

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-9-264945 (JP, A) JP-A-8-114670 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G01S 7/00-7/42 G01S 13/00-13/95 H04K 3/00

Claims (7)

(57) [Claims] 1. A waveform storage / reproduction means for receiving and storing a radar chirp wave, a waveform detection means for detecting a pulse waveform, a waveform read information calculation means for calculating a waveform read position / reproduction time, and And a control means for controlling each circuit. The radar chirp wave is stored by the waveform storing / reproducing means, and at the same time, the rising and falling positions of the radar chirp wave pulse are detected by the waveform detecting means to obtain the waveform read information. In the case of calculating and reading the waveform reading start position and end position for cutting out a pulse based on this detection information by the calculating means, reproducing the cutout pulse as a continuous pulse train repeatedly, and sending out as an interfering wave, the control means is , Find the center of the pulse for this continuously reproduced pulse, cut out from the center with an arbitrary width, and receive A modulator for an interfering device, which has a repetitive modulation function shorter than a pulse width. 2. A circuit in which a waveform synthesizing / forming unit for synthesizing and forming waveforms is added after the waveform storing / reproducing unit, wherein the control unit stores / receives the received radar chirp wave.
The pulse is taken up by the reproducing means, the leading and trailing edges of the pulse are amplitude-modulated in a slope shape, the trapezoidal / triangular waveform is formed by the waveform synthesizing / forming means, the slope portion of the waveform is superimposed, and the 2. The modulator for an interfering device according to claim 1, wherein the modulator has a modulating function of performing waveform synthesis such that the pulse width becomes constant, and continuously reproducing so that the repeating interval is shorter than the pulse width and transmitting as an interfering wave. 3. The waveform synthesizing / forming means delays the pulse waveform every 1 / N to N / N time of the pulse width of the received radar chirp wave to repeatedly reproduce, and N waveforms being simultaneously reproduced. 3. The modulator for an interfering device according to claim 2, further comprising a modulating function of superposing and combining the waveforms by the waveform synthesizing / forming means so as to have a constant amplitude, and continuously transmitting as an interfering wave. 4. The control means shortens a pulse width of a pulse that is continuously reproduced by cutting out the pulse with the passage of time,
2. The jammer modulator according to claim 1, wherein the pulse repetition period is shortened. 5. The control means makes the slope of the leading edge and the trailing edge of the pulse gentle as the time of continuous reproduction elapses to increase the overlap time of the slope portion and accelerate the pulse repetition period. The modulator for a jammer according to claim 2. 6. The modulator for a jammer according to claim 3, wherein the control means increases the number N of simultaneous reproductions with the lapse of continuous reproduction time. 7. A waveform storing / reproducing means for receiving and storing a radar chirp wave, a waveform detecting means for detecting a pulse waveform, a Doppler modulating means for performing Doppler modulation, and a waveform read position / reproducing time calculation. It is provided with a waveform read information calculation means for performing the above and a control means for controlling each of the above circuits. The radar chirp wave is stored by the waveform storing / reproducing means, and at the same time the rising and falling positions of the pulse of the radar chirp wave are waveform Detected by the detection means, the waveform read information calculation means calculates and reads the waveform read start position and the end position for cutting out the pulse based on this detected information, and the cut out pulse is repeated to reproduce as a continuous pulse train, and the Doppler modulation is performed. When the Doppler modulation is performed by the means and the interference wave is transmitted, the control means controls the continuous reproduction. That determine the center of the pulse to pulse, performs cut at any width from the center, Jammer for modulator characterized by having a modulation function of performing repetitive shorter than the received pulse width.