JP2904097B2 - Radio wave detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio wave detecting device, and more particularly, to a radio wave detecting device for measuring a distance to a source of an incoming radio wave.

[0002]

2. Description of the Related Art Conventionally, as a radio wave detecting device for detecting a source of an incoming radio wave and measuring a distance to the source, an azimuth of a direct wave arriving from the radio source is determined by a distance R on a receiving side.
There is a device that measures angles by two azimuth measuring devices located at points separated by just a distance and calculates a distance based on the obtained two angles and a distance between the two points. However, in this device, two direction measuring devices must be separated by a predetermined distance,
Distance measurement cannot be performed where the installation location is narrow.

Therefore, the elevation angle of the direct wave and the reflected wave of the radio wave from the emission source is measured, and the distance to the emission source is measured from the obtained elevation angle information and the height information input from the outside. The applicant of the present invention has proposed a device which does not require two separate measuring devices and enables measurement in a narrow place (see Japanese Patent Application Laid-Open No. 1-196588).

FIGS. 4 and 5 show a configuration and a principle diagram of a radio wave detecting device (distance measuring device) according to such a method. The elevation angle θH of the direct arrival wave S1 from the radio wave emission source To and the elevation angle of the reflection arrival wave S2 from the ground are measured by the direct wave measurement means 101 and the reflection wave measurement means 102 provided at the measurement reference point Ro at the same height position H. Measure θL. Based on the obtained elevation angle information θH, θL and the reference height information H, the calculating means 10
3 measures the distance to the radio wave emission source. Referring to FIG. 5, the radio waves received by the measurement reference Ro from the radio wave emission source To are a direct wave S1 and a reflected wave S2 reflected on the ground,
These incident angles (elevation angles) θH and θL are measured by the direct wave measuring means 1.
01 and the reflected wave measuring means 102. Calculation means 1
Numeral 03 can calculate the distance W to the radio wave emission source of the arriving radio wave by geometric calculation based on the altitude H of the measurement point and the incident angle information θH and θL.

According to the conventional radio wave detection apparatus shown in FIGS. 4 and 5, even if the measurement point is narrow, the distance to the radio wave emission source of the arriving radio wave can be measured.

However, in such a radio wave detection device,
Although it is necessary to receive the direct wave and the reflected wave independently, if the direct wave measuring means and the reflected wave measuring means are installed at the same position, the direct wave and the reflected wave become independent due to diffraction and scattering due to the nature of radio wave propagation. Since it is very difficult to receive the data, there is a problem that effective measurement cannot be performed.

[0007]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to eliminate the need to measure the direct wave and the reflected wave independently (separately), and to measure the distance to the radio wave source with high accuracy even in a narrow place. To provide a radio wave detection device.

[0008]

In order to solve the above-mentioned problems, a radio wave detecting apparatus according to the present invention comprises a plurality of antennas arranged in a vertical direction, the amplitude of a received signal of an incoming radio wave from a radio wave emitting source. Based on the information, determine the period of the height pattern indicating a change in amplitude in the vertical direction, and measure the distance to the radio wave emission source based on the obtained height pattern period information and the height information of the radio wave emission source. It is composed of

A radio wave detecting device according to another aspect of the present invention is provided in correspondence with a plurality of antennas disposed in a vertical direction and the plurality of antennas, and measures the amplitude of a reception signal of the corresponding antenna. A plurality of amplitude measurement circuits; a height pattern cycle calculation circuit that calculates a height pattern cycle indicating a vertical amplitude change of a received signal based on amplitude information from the plurality of amplitude measurement circuits; A specification measurement circuit for measuring specifications, an identification circuit for identifying a mounting base of the radio wave emission source based on the radio specification measured by the specification measurement circuit, and predetermined altitude information for each mounting base. And an altitude output circuit that obtains the altitude of the radio wave emission source based on the mounted body identification result obtained by the identification circuit, and height pattern cycle information calculated by the height pattern cycle calculation circuit, Serial constructed and a distance calculation circuit for calculating a distance to the radio wave source based on the obtained altitude information with a high degree output circuit.

A radio wave detecting apparatus according to still another aspect of the present invention is provided with a plurality of antennas disposed in a vertical direction and corresponding to the plurality of antennas, and divides a reception signal of a corresponding antenna into two. A divider for outputting, one output of the divider, a plurality of amplitude measuring circuits for measuring the amplitude of the received signal of the corresponding antenna, and selectively outputting one of all other outputs of the divider A switch, a control circuit that controls the switch so as to selectively output a reception signal from an antenna having a maximum amplitude among the amplitudes output from the plurality of amplitude measurement circuits, and an output from the switch. A specification measurement circuit for measuring the radio characteristics of the corresponding received arriving radio wave, and an identification circuit for identifying the mounting base of the radio wave emission source based on the radio characteristics measured by the specification measurement circuit,
An altitude output circuit for obtaining the altitude of the radio wave emitting source based on predetermined altitude information for each mounting base and the mounting base identification result obtained by the identification circuit; and a height pattern calculated by the height pattern cycle calculating circuit. A distance calculating circuit configured to calculate a distance to the radio wave emitting source based on the period information and the altitude information obtained by the altitude output circuit.

Here, the parameters measured by the parameter measuring circuit are a frequency, a pulse width, and a pulse repetition frequency which are parameters required for identification. The reception signal output to the specification measurement circuit is a reception signal received by one separately provided antenna or a plurality of separately provided antennas.

[0012]

FIG. 1 is a block diagram showing the configuration of an embodiment of a radio wave detecting device according to the present invention. FIG. 2 is a diagram showing an example of a height pattern for explaining the embodiment of FIG.

The n antennas 11, vertically arranged,
12,. . . , 1n receive n correspondingly installed amplitude measuring circuits 21, 22,. . . 2n and the respective amplitudes are measured. The height pattern cycle calculation circuit 3 includes amplitude measurement circuits 21, 22,. . . 2
The height pattern period is calculated based on the amplitude information received from n and sent to the distance calculation circuit 4.

On the other hand, the radio wave specification of the received signal received by the antenna for specification measurement 5 is measured by the specification measurement circuit 6, and the identification circuit 7 detects the radio wave source based on the measured radio wave specification. The mounting mother is identified. The altitude output circuit 8 obtains an altitude based on the identification result information sent from the identification circuit 7 and sends it to the distance calculation circuit 4.

The distance calculating circuit 4 calculates the distance to the radio wave emitting source based on the height pattern cycle information sent from the height pattern cycle calculating circuit 3 and the altitude information sent from the altitude output circuit 8 as described above. Is calculated and output.

The principle of the distance measurement according to the embodiment shown in FIG. 1 will be described below with reference to FIG. As described above, the radio wave reception signal from the radio wave emission source at the measurement point is a composite signal of the direct wave and the reflected wave, and since this composite signal has a different amplitude level depending on the altitude of the reception point, it is arranged vertically. The antennas 11, 12,. . . The amplitude level of the received signal received at 1n differs for each antenna. In FIG. 2, the reception amplitude level of the antenna 11 at the altitude h1 is P1, and the reception amplitude level of the antenna 12 at the altitude h2 is P1.
2. The reception amplitude level of the antenna 13 at the altitude h3 is P3, and similarly, the reception amplitude level of the antenna 1n is Pn (not shown). The height pattern cycle calculation circuit 3 is configured as shown in FIG.
, A height pattern indicating a change in the amplitude level of the received signal accompanying a change in the reception altitude indicated by a black circle is calculated, and a cycle L of the height pattern is calculated.

The specification measuring circuit 6 measures the frequency, pulse width, pulse repetition frequency, and the like required for identification from the received signal received by the specification measurement antenna 5. Based on the information, the radio wave emission source, for example, the model name of the radar is identified by the identification circuit 7, and then the mounting base on which the identified radio emission source is mounted is identified.
The altitude output circuit 8 obtains and outputs the altitude at which the mounting base exists from the identified mounting base.

In general, the following relationship exists between the height pattern period L, the signal wavelength λ, the altitude H of the radio wave source, and the distance W from the radio source to the receiving point. L = λW / 2H

Therefore, the distance calculating circuit 4 calculates the height pattern period L sent from the height pattern period calculating circuit 3, the altitude H sent from the altitude output circuit 8, and the frequency measured by the specification measuring circuit 6. The distance to the radio wave emission source can be obtained.

FIG. 3 is a block diagram showing the configuration of another embodiment of the radio wave detecting device according to the present invention. In the present embodiment, FIG.
In the embodiment of the present invention, the antenna 5 for specification measurement is replaced by the antennas 11, 12,. . . 1n.

In this example, the antennas 11, 12,. . . 1n
And the amplitude measurement circuits 21, 22,. . . 2n, distributors 91, 92,. . . 9n are provided respectively. The distributors 91, 92,. . . Each output of 9n is connected to the input of switch 10.
The height pattern cycle calculation circuit 3 includes distributors 91 and 9
2,. . . 9n are amplitude measurement circuits 21, 22,. . . 2n
Side, the amplitude measurement circuits 21, 22,. . . The height pattern period is calculated from the amplitude information from 2n, the antenna (channel) having the largest amplitude is detected, and the signal from the antenna receiving the received signal having the largest amplitude is supplied to the specification measuring circuit 6. The switch 10 is controlled in order to perform this. The operations of the specification measurement circuit 6, the identification circuit 7, the altitude output circuit 8, and the distance calculation circuit 4 are the same as those of the embodiment shown in FIG. Is output.

In the embodiment shown in FIG. 1, there is only one antenna for specification measurement. On the other hand, in the embodiment shown in FIG. 3, the number of antennas for measurement is n. Since the radio wave specifications are measured from the received signal having the maximum amplitude, the distance measurement can be performed with higher accuracy without being affected by the height pattern.

[0023]

As described above, the radio wave detection device according to the present invention can measure the distance based on the height pattern period obtained from the signal received from the vertically disposed antenna, so that the radio wave It is not necessary to receive the direct wave and the reflected wave, and the direct wave and the reflected wave can avoid the deterioration of the distance measurement accuracy caused by the phenomenon such as the diffraction and scattering of the radio wave, and the distance measurement can be performed with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration block diagram illustrating an embodiment of a radio wave detection device according to the present invention.

FIG. 2 is a diagram showing an example of a height pattern for explaining the embodiment of FIG. 1;

FIG. 3 is a configuration block diagram of another embodiment of the radio wave detection device according to the present invention.

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

FIG. 5 is a diagram showing the principle of a conventional radio wave detection device.

[Explanation of symbols]

11, 12,. . . , 1n antennas 21, 22,. . . , 2n amplitude measurement circuit 3 height pattern cycle calculation circuit 4 distance calculation circuit 5 antenna for specification measurement 6 specification measurement circuit 7 identification circuit 8 advanced output circuit 91, 92,. . . , 9n distributor 101 direct wave measuring means 102 reflected wave measuring means 103 computing means

Claims (6)

(57) [Claims] 1. A period of a height pattern indicating a change in amplitude in a vertical direction is obtained based on amplitude information of a reception signal of an incoming radio wave from a radio wave emission source obtained by a plurality of antennas arranged in a vertical direction, A radio wave detection device for measuring a distance to the radio wave emission source based on the obtained height pattern cycle information, height information of the radio wave emission source, and signal wavelength information . 2. A plurality of antennas disposed in a vertical direction, a plurality of amplitude measurement circuits provided corresponding to the plurality of antennas, and measuring an amplitude of a reception signal of the corresponding antenna, and the plurality of amplitude measurement. A height pattern period calculating circuit that calculates a period of a height pattern indicating a vertical amplitude change of a received signal based on amplitude information from a circuit; a specification measuring circuit that measures radio wave characteristics of a received arriving radio wave; An identification circuit for identifying the mounting base of the radio wave emission source based on the radio characteristics measured by the specification measurement circuit; and predetermined altitude information for each mounting base and the mounting base identification result obtained by the identification circuit. wherein the height output circuit for obtaining a high degree of radio wave source, the height pattern period information calculated in the height pattern cycle calculation circuit, and altitude information obtained by the height output circuit based on electrodeposition Radiolocation apparatus characterized in that it comprises a distance calculation circuit for calculating a distance to the radio wave source on the basis of the wavelength information in the specifications. 3. A plurality of antennas disposed in a vertical direction, a distributor provided corresponding to the plurality of antennas, for branching and outputting a reception signal of the corresponding antenna into two, and one of the distributors A plurality of amplitude measurement circuits for receiving the output and measuring the amplitude of the reception signal of the corresponding antenna; a switch for selectively outputting one of all other outputs of the distributor; and a plurality of the amplitude measurement circuits. A control circuit for controlling the switch so as to selectively output a reception signal from the antenna having the largest amplitude among the output amplitudes, and measuring a radio wave characteristic of a reception arriving radio wave corresponding to the output from the switch. A specification measurement circuit to perform, an identification circuit for identifying a mounting base of the radio wave emission source based on the radio specification measured by the specification measurement circuit, and a predetermined altitude information for each mounting base and the identification circuit. Obtained in An altitude output circuit that determines the altitude of the radio wave emission source based on the mounted mother body identification result, height pattern cycle information calculated by the height pattern cycle calculation circuit, and altitude information obtained by the altitude output circuit, A radio wave detection device comprising: a distance calculation circuit that calculates a distance to the radio wave emission source based on wavelength information in radio wave data. 4. The radio wave detection device according to claim 2, wherein the parameters measured by the parameter measuring circuit are a frequency, a pulse width, and a pulse repetition frequency which are parameters required for identification. 5. A received signal output to the specification measuring circuit,
3. The radio wave detection device according to claim 2, wherein the radio signal is a reception signal received by one separately provided antenna. 6. A received signal output to the specification measuring circuit,
The radio wave detection device according to claim 2, wherein the radio wave detection device is a reception signal received by a plurality of separately provided antennas.