JPH0996667A - Radar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the detection efficiency by determining the incoming direction of radio wave even when a radio wave is received from a source by a side lobe along with a main beam thereby detecting the azimuth of a radio wave source in a short time. SOLUTION: An angle detector 14 detects the rotational angle of a rotary directional antenna 12 and a receiver 13 outputs an amplitude variation pattern indicative of the receiving field strength pattern obtained for every rotational angle detected by the angle detector 14 at receiving frequency. A pattern collation circuit 15c compares the amplitude value variation pattern obtained from the receiver 13 with a beam pattern stored in a pattern memory circuit 15b and determines the incoming direction of radio wave from the matched part of pattern.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave detection device for determining the direction of a radio wave transmission source from a received signal of a rotating directional antenna (antenna).

[0002]

2. Description of the Related Art Conventionally, in a radio wave detection device for calculating the direction of a radio wave transmission source such as a radar, a parabolic or multi-element type rotary directional antenna and an omnidirectional antenna such as a ground plane are used to simultaneously detect radio wave transmission sources. Then, the direction of the radio wave transmission source is calculated from the main beam direction (the maximum electric field strength point) of the rotating directional antenna.

FIG. 4 is a block diagram showing the configuration of a conventional radio wave detection apparatus. In the example of FIG. 4, radio waves from a radio wave transmission source (not shown) having a directivity in the plane of horizontal polarization and received by the rotating directional antenna 2 are received, and this received signal is sent to the receiver 3. Further, the reception signal received by the omnidirectional antenna 4 having omnidirectionality in the plane of horizontal polarization is input to the receiver 3.

The receiver 3 amplifies the received signal, for example,
In addition, frequency conversion and detection are performed to output an amplitude value corresponding to the electric field strength of the received radio wave, and the measured value is output to the amplitude comparison circuit 5a of the signal processing unit 5. The amplitude comparison circuit 5a compares the amplitude values of the respective reception signals received by the rotary directional antenna 2 and the omnidirectional antenna 4 output by the receiver 3, and if the difference is not zero, the difference between the amplitude values is calculated. The value is output to the angle calculation circuit 5b.

In the angle calculation circuit 5b, the amplitude comparison circuit 5a
The value from the angle detector 6 for detecting the difference value of the amplitude values output by the and the current angle (azimuth) of the rotating directional antenna 2 in the main beam direction is stored as a set. This memory stores 360 ° for one rotation of the rotating directional antenna 2. Then, the angle calculation circuit 5b calculates data in which the difference value of the amplitude values in the data stored here is larger than zero, and detects the minimum value and the maximum value in this angle.
The midpoint between the minimum value and the maximum value is output as direction detection data indicating the arrival direction of the radio wave.

As a conventional example of this type, Japanese Patent Laid-Open No. 62-20
No. 1380, “Azimuth Measuring Device” can be mentioned. In this conventional example, two antennas, which are arranged inverted in the direction of 180 °, are simultaneously rotated, and the received signals are combined and sent to the receiver. The receiver separates the azimuth measurement processing. As a result, the azimuth measurement of the radio wave is performed twice for each rotation of the antenna.

[0007]

However, in the former radio wave detection device of the above-mentioned conventional example, since the arrival direction of the radio wave can be detected only when it is received by the main beam of the rotary directional antenna 2, the direction detection is performed. Will take a lot of time. That is, the arrival direction of the radio wave cannot be detected unless it makes at least one rotation. Further, when the gain of the main beam of the rotational directional antenna 2 with respect to the arrival direction of the radio wave is low, the main beam cannot receive the side lobe in the beam pattern of the radio wave transmission source such as a radar. In other words, the direction can be detected only when the transmitted wave of the main beam of a radio wave transmission source such as a radar is received by the main beam of the rotating directional antenna 2, and the detection efficiency is lowered.

In the conventional example of the publication, the azimuth of the radio wave can be measured twice for each rotation of the antenna. In other words, it becomes the same as the case where the azimuth is measured by rotating one antenna twice, and although the azimuth measuring time can be shortened to 1/2, this rotation cannot be rotated further due to the structural strength of the antenna. . Therefore, similarly to the former example, it is not possible to further shorten the detection time of the arrival direction of the radio wave. Further, similarly to the former example, the direction can be detected only when the transmitted wave of the main beam of the radio wave transmission source such as a radar is received by the main beam of the rotating directional antenna 2, and the detection efficiency thereof is further improved. There is a drawback that cannot

The present invention solves the problems in the prior art as described above, and the arrival direction of the radio wave can be determined even when the radio wave from the transmission source is received by the side lobe together with the main beam. Provided is a radio wave detection device capable of detecting the direction of the radio wave transmission source in a short time and improving detection efficiency.

[0010]

In order to achieve the above-mentioned object, a radio wave detecting apparatus according to the invention of claim 1 is a rotary directional antenna, and a rotation angle detecting means for detecting a rotation angle of the rotary directional antenna. Means, a receiving means for outputting a pattern of amplitude value change showing a received electric field intensity pattern obtained at a receiving frequency for each rotation angle detected by the rotation angle detecting means, and a beam pattern of the rotary directional antenna are stored in advance. A pattern storage means and a pattern collation means for comparing the amplitude value change pattern obtained by the receiving means with the beam pattern stored in the pattern storage means to determine the arrival direction of the radio wave from the matched pattern portion. It is as a configuration.

According to a second aspect of the radio wave detecting apparatus, the receiving means stores the range of the rotation angle detected by the rotation angle detecting means and the angle reception signal storage means for storing a pattern of the amplitude value change in this range as a set. The pattern of the rotation angle range and the amplitude value change output from the angle reception signal storage means is sent to the pattern matching means, and the time axis is matched with the beam pattern stored in the pattern storage means for comparison. It is configured to do so.

In the radio wave detecting device according to the present invention, the pattern matching means has a pattern of amplitude value change in one range of the rotation angle and the beam pattern stored in the pattern storage means, the amplitude value axis and angle. The axes are moved in parallel to be coincident with each other, and the amplitude value difference in the pattern of amplitude value change in one range of the rotation angle and the angle difference in the beam pattern stored in the pattern storage means are calculated by the least squares method. The angle range in which the error is minimized is detected and collated.

A radio wave detecting apparatus according to a fourth aspect of the present invention corresponds to a rotary directional antenna that outputs a reception signal obtained by receiving a radio wave from a radio wave source while rotating at a constant speed, and an electric field strength from a reception signal from the rotation directional antenna. Receiving means for outputting amplitude value data and frequency data, which are patterns of amplitude value change, time measuring means for measuring time, angle detecting means for outputting rotation angle data of the rotational directional antenna, and one of the time measuring means. Time amplitude value storage means for storing the pattern of the amplitude value change output by the receiving means between two times as one set, and one set of the data of the pattern of the time value and the amplitude value change output by the time amplitude value storage means as one set. Time angle conversion means for converting and outputting the set of rotation angle and amplitude value change pattern data, and the rotation angle and rotation angle of the rotation directional antenna for each frequency received in advance. A pattern storage means for storing a beam pattern consisting of a set of data of amplitude value change patterns, a set of rotation angle and amplitude value change pattern data converted by the time angle conversion means, and a rotation stored in the pattern storage means. Pattern collating means for outputting angle range data comparing a beam pattern consisting of a set of data of angle and amplitude value change patterns, and rotation angle of the rotation directional antenna between times output by the angle detecting means and An angle calculation unit that calculates the angle of the arrival direction of the radio wave from the data of the angle range output by the pattern matching unit is provided.

According to the radio wave detecting apparatus of the invention described in claims 1, 2, 3, and 4, the rotation angle of the rotary directional antenna is detected, and the reception electric field obtained for each rotation angle at the reception frequency is obtained. Compare the amplitude value change pattern indicating the intensity pattern with the pre-stored beam pattern, and determine the arrival direction and angle of the radio wave from the matched pattern part. The arrival direction of the radio wave is determined even when the radio wave from the source is received, and the direction of the radio wave transmission source is detected in a short time.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a radio wave detection apparatus of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a first embodiment of the radio wave detection apparatus of the present invention. The example of FIG. 1 is provided with a rotary directional antenna 12 which has directivity in a plane of horizontal polarization and which rotates and outputs a reception signal which receives a radio wave from a radio wave transmission source such as a radar (not shown). .

Further, the received signal from the rotary directional antenna 12 is amplified, frequency converted and detected to correspond to the electric field strength of the received radio wave, and
A receiver 13 that outputs amplitude value data, which is a pattern of amplitude value change, and frequency data indicating a reception frequency, based on the beam pattern characteristics of the rotating directional antenna 12,
The angle detector 14 that constantly detects the current angle (azimuth) of the rotating directional antenna 12 in the main beam direction and outputs the angle data, the angle data and the amplitude value data, and the beam pattern stored in advance. The signal processing unit 15 collates and determines the arrival direction of the received radio wave (radio wave transmission source direction).

The signal processing section 15 includes an angle reception signal storage circuit 15a for storing the angle data output by the angle detector 14 and the amplitude value data output by the receiver 13 as a set.
When the frequency data output by the receiver 13 is input,
A pattern storage circuit 1 for outputting a beam pattern corresponding to a reception frequency from the beam patterns of the main beam and side lobes of the rotary directional antenna 12 stored in advance.
5b and the set of angle data and amplitude value data from the angle reception signal storage circuit 15a and the beam pattern of the rotary directional antenna 12 stored in the pattern storage circuit 15b are collated, and the beam pattern and the amplitude value change The pattern matching circuit 15c determines the arrival direction of the received radio wave from the angular range of the pattern portion where the pattern matches.

Next, the operation of the first embodiment will be described. FIG. 2 is a diagram for explaining the operation of the first embodiment. FIG. 2A shows the amplitude value data (amplitude value AS) output by the receiver 13 when the rotary directional antenna 12 receives a radio wave from the direction x while the main beam rotates from the angle MS to the angle ME. To change pattern of amplitude value AE)
Is shown. FIG. 2B is an enlarged view showing a change pattern of the amplitude value AS to the amplitude value AE during the rotation from the angle MS to the angle ME in FIG. FIG. 2C is a diagram for explaining the arrival direction x of the received radio wave.

In FIGS. 1 and 2, the rotary directional antenna 12 receives a radio wave from the direction x, and the received signal is input to the receiver 13. The receiver 13 amplifies the received signal, for example, performs frequency conversion and detection to correspond to the electric field strength of the received radio wave, and changes the amplitude value based on the beam pattern characteristic of the rotary directional antenna 12. The amplitude value data that is a pattern is output to the angle reception signal storage circuit 15a in the signal processing unit 15. At the same time, the receiver 13 measures the frequency f of the received signal and outputs the frequency data to the pattern storage circuit 15b in the signal processing unit 15,
The frequency data is stored here.

In the angle reception signal storage circuit 15a in the signal processing unit 15, the angle value (azimuth) of the current main beam azimuth of the rotary directional antenna 12 output from the amplitude value data output from the receiver 13 and the angle detector 14 is output. It also stores data. That is, when a radio wave from the azimuth x is received, it is a pattern of amplitude value change corresponding to the rotation angle of the amplitude value AS to the amplitude value AE during the rotation from the angle MS to the angle ME shown in FIG. 2B. Store the amplitude value data.

A set of angle data and amplitude value data corresponding to the rotation angle from the angle reception signal storage circuit 15a is input to the pattern matching circuit 15c. Further, the data of the frequency f stored in the pattern storage circuit 15b is input to the pattern matching circuit 15c. The pattern matching circuit 15c matches the beam pattern of the rotational directional antenna 12 stored in advance, which corresponds to the frequency f,
The arrival azimuth x of the received radio wave is determined from the angle range of the pattern portion that is matched in this collation. If the coincident angle range is changed from the angle PS to the angle PE in FIG. 2C, the angle of the arrival azimuth x of the radio wave is "angle MS + angle PS".

The pattern matching circuit 15c matches the set of angle data and amplitude value data from the angle reception signal storage circuit 15a with the beam pattern of the rotary directional antenna 12 by, for example, changing the amplitude value in the range of the rotation angle. And the beam pattern stored in the pattern storage circuit 15b are moved in parallel on the amplitude value axis and the angle axis to be coincident with each other, and a difference value between the amplitude values of the pattern of the amplitude values in the range of the rotation angle, The values of the beam pattern and the angle difference stored in the pattern storage circuit 15b are calculated by the least-squares method and processed into values that are easy to compare, and the angle range in which the error is minimized is detected and collated. .

Thus, in the first embodiment,
The amplitude value change pattern indicating the electric field intensity pattern obtained by the receiver 13 is compared with the beam pattern stored in the pattern storage circuit 15b, and the angular range of the stored beam pattern corresponding to the matched pattern portion is compared. Then, the arrival direction of the radio wave is determined from this angle range and the main beam angle. Therefore, even when the radio wave from the transmission source is received by the side lobe together with the main beam, the arrival direction of the radio wave can be determined. In other words, the direction of the radio wave transmission source can be detected at any rotation angle, and radio wave detection can be performed efficiently in a short time.

Next, a second embodiment will be described. FIG. 3 is a block diagram showing the configuration of the second embodiment. FIG.
Is a horizontal directional antenna, has a directivity in a horizontal polarization plane, and rotates R per unit time, and outputs a reception signal that receives a radio wave from a radio wave transmission source (not shown); The received signal from 12 is amplified, frequency converted and detected, for example, to correspond to the electric field strength of the received radio wave, and the directional antenna 12
It has a receiver 13 which outputs amplitude value data and frequency data obtained by measuring a pattern of amplitude value change and a reception frequency based on the beam pattern characteristic of 1. and a clock 16 which measures time. Further, it has an angle detector 17 that outputs rotation angle data of the rotation directional antenna 12 for each time, and a signal processing unit 20 that outputs azimuth detection data.

The signal processing unit 20 stores a time amplitude value storage circuit 21 for storing a set of amplitude value data output by the receiver 13 during a certain time and during the time measured by the clock 16, and at this time. A time-angle conversion circuit 22 is provided which converts a set of time and amplitude value data input from the amplitude value storage circuit 21 into a set of rotation angle and amplitude value change pattern data and outputs the data. .

An angle obtained by comparing a set of rotation angle and amplitude value data converted by the time-angle conversion circuit 22 with a horizontal plane beam pattern composed of a set of rotation angle and amplitude value data of the frequency. A pattern matching circuit 23 that outputs range data to the angle calculation circuit 25, and a pattern that stores a horizontal plane beam pattern corresponding to a set of data of the rotation angle and the amplitude value of the rotation directional antenna 12 for each frequency received in advance. And a memory circuit 24. Further, it has an angle calculation circuit 25 for transmitting the direction detection data indicating the angle of the arrival direction of the radio wave.

Next, the operation of the second embodiment will be described. In FIG. 3, when the rotational directional antenna 12 receives a radio wave transmitted from a radar or the like and rotates from time TS to time TE, the received signal is input to the receiver 13. In the receiver 13, for example, the received signal from the rotary directional antenna 12 is amplified, and frequency conversion and detection are performed to correspond to the electric field strength of the received radio wave, and the beam pattern of the rotary directional antenna 12 is obtained. The amplitude value data, which is a pattern of the amplitude value change based on the characteristics, and the data of the frequency f are output.

The amplitude value data output from the receiver 13 is input to the time amplitude value storage circuit 21 of the signal processing unit 20, and the frequency data of the reception frequency f is the pattern storage circuit 2.
4 is input. In the time amplitude value storage circuit 21, the clock 16
The time T measured by A and the amplitude value AT output by the receiver 13 at this time T are set as a set (time T, amplitude value AT), and are stored from time TS to time TE. The data of the time T and the amplitude value AT from the time amplitude value storage circuit 21 are input to the time angle conversion circuit 22. The time-angle conversion circuit 22 converts the input set of time T and amplitude value AT data into a set of rotation angle and amplitude value data.

In this conversion, the time T is converted by the angle .theta. = R (T-TS) of the main beam azimuth of the rotary directional antenna 12, the amplitude value AT at the time T is left unchanged, and A.theta.
In the case of "T-TS", .theta. = 0. Here, θ = θE when T = TE. In this case, since the direction of the horizontal plane beam pattern angle axis of the rotational directional antenna 12 is opposite, (θ, Aθ) is converted to (θE −θ, Aθ). If θa = θE −θ, then θa = when θ = 0
θE, and θa = 0 when θ = θE. Angle θ
The amplitude value Aθ at that time is left as it is, and this will be represented later by Aθa.

A set of rotation angle and amplitude value data converted by the time angle conversion circuit 22 is output to the pattern matching circuit 23. Further, the pattern storage circuit 24 stores a horizontal plane beam pattern corresponding to a set of data of the rotation angle and the amplitude value of the rotation directional antenna 12 for each frequency received in advance. When the frequency data of the reception frequency f is input from the receiver 13 to the pattern storage circuit 24, a horizontal plane beam pattern corresponding to a set of data of the rotation angle and the amplitude value of the rotation directional antenna 12 corresponding to the frequency f. To the pattern matching circuit 23.

In the pattern matching circuit 23, a set of rotation angle and amplitude value data (θa, Aθa) converted by the time angle conversion circuit 22 and the rotation angle and amplitude value of the frequency f output from the pattern storage circuit 24. The data from the angular range BS to the angular range BE, which are collated with the horizontal plane beam pattern consisting of one set of data, are output to the angle calculation circuit 25.

In the angle calculation circuit 25, the rotation angle θ M of the rotation directional antenna 12 at the time TS output from the angle detector 17 and the angle range B output from the pattern matching circuit 23.
The arrival azimuth of the radio wave from S to the angle range BE is calculated by the rotation angle θM + angle range BS, and the azimuth detection data indicating the angle of this arrival azimuth is transmitted.

In this way, in the second embodiment, the amplitude value change pattern corresponding to the received electric field intensity pattern obtained for each rotation angle at the reception frequency is compared with the beam pattern stored in advance. The arrival angle of the radio wave is determined from the matched pattern part, and the arrival angle of the radio wave is calculated even when the radio wave from the transmission source is received in the side lobe together with the main beam. Done in time.

[0034]

As is apparent from the above description, according to the radio wave detection device of the invention described in claims 1 to 4, the reception electric field intensity pattern obtained at the reception frequency for each rotation angle of the rotary directional antenna. Since the arrival direction of the radio wave and its angle are determined from the pattern part that matches the amplitude value change pattern indicating the and the beam pattern stored in advance, the radio wave from the transmission source is side-lobe with the main beam. Even when received, the arrival direction of the radio wave and its angle can be determined. That is, the azimuth of the radio wave transmission source can be detected in a short time at any rotation angle of the rotary directional antenna, and its detection efficiency is improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration in a first embodiment of a radio wave detection device of the present invention.

FIG. 2 is a diagram for explaining the operation of the first embodiment. (A) shows the amplitude value data when the rotation directional antenna rotates. (B) shows an enlarged amplitude value change pattern. (C) is for explaining the arrival direction of the received radio wave.

FIG. 3 is a block diagram showing a configuration of a second embodiment.

FIG. 4 is a block diagram showing a configuration of a conventional radio wave detection device.

[Explanation of symbols]

 12 rotation directional antenna 13 receiver 14,17 angle detector 15,20 signal processing unit 15a angle reception signal storage circuit 15b, 24 pattern storage circuit 15c, 23 pattern matching circuit 16 clock 21 time amplitude value storage circuit 22 time angle conversion Circuit 25 Angle calculation circuit

Claims (4)

[Claims] 1. A rotary directional antenna, a rotation angle detecting means for detecting a rotation angle of the rotary directional antenna, and a reception electric field obtained at a reception frequency for each rotation angle detected by the rotation angle detecting means. Receiving means for outputting an amplitude value change pattern indicating an intensity pattern, pattern storage means for preliminarily storing the beam pattern of the rotary directional antenna, amplitude value change pattern and the pattern storage obtained by the receiving means. A radio wave detection device comprising: a pattern matching unit that compares the beam pattern stored in the unit and determines the arrival direction of the radio wave from the matched pattern portion. 2. The receiving means is provided with an angle reception signal storage means for storing a range of the rotation angle detected by the rotation angle detection means and a pattern of amplitude value change in this range as a set, and the angle reception signal storage is provided. It is preferable that the range of the rotation angle and the pattern of the amplitude value change output by the means are sent to the pattern matching means, and the time axis of the beam pattern stored in the pattern storage means is matched and compared. The radio wave detection device according to item 1. 3. The pattern matching means matches the amplitude value change pattern in one range of the rotation angle and the beam pattern stored in the pattern storage means by moving the amplitude value axis and the angle axis in parallel. And, the difference in amplitude value in the pattern of the change in amplitude value in one range of the rotation angle and the angle difference in the beam pattern stored in the pattern storage means are calculated by the least square method, and the error is minimized. The radio wave detection device according to claim 1, wherein the angle range is defined as follows. 4. A rotation directional antenna that sends out a reception signal that receives a radio wave from a radio wave source while rotating at a constant speed, and a pattern of an amplitude value change corresponding to an electric field strength from the reception signal from the rotation directional antenna. Receiving means for outputting certain amplitude value data and frequency data, time measuring means for measuring time, angle detecting means for outputting the rotational directional antenna rotation angle data, and receiving means for one time in the time measuring means Time amplitude value storage means for storing the pattern of the amplitude value change output as a set, and a set of time and amplitude value change pattern data output by the time amplitude value storage means as a set of the rotation angle and Time-angle conversion means for converting and outputting the data of the pattern of amplitude value change, and rotation angle and amplitude value change of the rotational directional antenna for each frequency received in advance Pattern storage means for storing a beam pattern consisting of a set of data of the pattern, a set of rotation angle and amplitude value change pattern data converted by the time angle conversion means, and a rotation angle stored by the pattern storage means. And a pattern collating means for outputting angle range data comparing a beam pattern consisting of a set of patterns of amplitude value change, and a rotation angle of the rotation directional antenna between time points output by the angle detecting means, An electric wave detection device comprising: an angle calculation unit that calculates an angle of a direction of arrival of a radio wave from data of an angle range output by the pattern matching unit.