JP2002214316A - Azimuth evaluation device and azimuth evaluation method for radio emitting source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in a conventional azimuth evaluation device for measuring the azimuth of a radio emitting source that a directivity pattern is disordered by the electric influence of a mounting parent body such as air plane, naval vessel, when mounted on the parent body, to increase the azimuth orientation error. SOLUTION: The own position is measured by a GPS device 5. An azimuth correcting device 6 calculates the map azimuth of a target 98 from the own position and the position of the target 98 having a known position. An azimuth detector 3 receives the radar wave from the target, and detects the radio azimuth. The azimuth correcting device 6 compares this radio azimuth with the map azimuth to obtain the correction value of error of the radio azimuth, and stores it. When the azimuth of an unknown target is detected, it is corrected with the correction value, whereby a precise azimuth evaluation result can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in the detection accuracy of a radio wave source azimuth estimating apparatus for locating the radio wave source by the reverse detection of the direction of the radio wave source.

[0002]

2. Description of the Related Art FIG. 7 illustrates the configuration of a conventional azimuth locating apparatus based on radio wave back search, which evaluates the azimuth of a radio wave emission source by back detection of the azimuth of a radio wave emission source (hereinafter referred to as radio back search). Numeral 12 denotes a radio wave emission source target which emits a radio wave to be detected. Numeral 2 denotes an antenna of a radio wave reverse search device, which is not shown in the drawing but is mechanically (for example, a rotating device) or electrically (for example, a phased array). (Antenna) The antenna is configured so that it can be directed in any direction including the direction in which it is desired to detect the directivity direction. Reference numeral 1 denotes a unique directivity pattern of the antenna 2 (the direction can be controlled as described above), and FIG. 8A shows a two-dimensional planar development pattern. Reference numeral 3 denotes an azimuth detecting device for detecting the azimuth of a target radio wave emission source connected to the antenna 2, and includes a circuit for analyzing the intensity of a received signal and a circuit for detecting the direction of the antenna 2. Note that the antenna 2 and the azimuth detecting device 3 constitute a radio wave reverse search device 100.

Next, the operation will be described. The radio wave emitted from the radio wave emission source target 12 is received by the antenna 2 of the radio wave search device 100. At this time, at the angle where the main lobe of the directivity pattern 1 of the antenna 2 faces the direction of the target 12, the target radio wave can be received at a maximum, so that direction becomes the target direction, and the direction of the antenna 2 at this time is the direction detection. The direction of the target 12 is detected by the device 3.

The directivity pattern 1 of the antenna 2 of the radio wave searching device 100 is accurately grasped as the radio wave searching device 100 alone, and is adjusted so as not to have an azimuth error. However, the radio wave reverse search device 100 is mounted on a mounting base such as an aircraft or a ship, and even when used on the ground, a large number of other wireless antennas are arranged close to each other. Disturbance (deformation or angle shift) of the directivity pattern 1 is caused by the influence of another antenna. As an example, FIG. 8B shows a modified directivity pattern. In FIG. 8B, the directivity pattern is deformed to about 20
The main lobe is moving in the ° direction. Of course, there is a case where only the angle shift occurs without changing the shape of the pattern. In addition, the shape of the directional pattern 1 may be deformed or misaligned due to a partial contact failure of the element antenna constituting the antenna 2 due to long-term use. If the user continues to use such a state without noticing such a state, for example, FIG.
In the state (b), an erroneous azimuth is detected as if the azimuth of the target actually in the 20 ° direction is in the 0 ° direction.

[0005]

Since the conventional azimuth locating apparatus is configured as described above, it has the following problems.
The directivity pattern of the antenna of the radio wave reverse search device is based on the fact that the radio wave reverse search device is mounted on a mounting base such as an aircraft, or even if it is installed on the ground, other wireless antennas are installed at close distances, etc. Disturbance of the directivity pattern occurs due to the influence of the shape of the mounting base and the influence of other antennas. In addition, the directional pattern may be disturbed due to deterioration of the antenna due to long-term use. Due to the disturbance of the directivity pattern, the orientation of the target of the radio wave emission source is incorrectly located.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and automatically corrects an azimuth locating error caused by disturbance of a directivity pattern, thereby locating the azimuth of a radio wave emitting source with high accuracy. It is intended to obtain an azimuth locating device capable of performing the following.

[0007]

SUMMARY OF THE INVENTION An azimuth estimating apparatus for a radio wave emitting source according to the present invention comprises: an antenna having directivity; a directional control means for controlling the directional direction of the antenna; a radio wave radiated from a target received by the antenna; Direction detection device that detects the radio wave direction of the target from the received signal strength, GP that can measure its own position
S device, radio wave source obtained by calculating the radio azimuth obtained by the azimuth detecting device by receiving the radio wave of the radio wave source whose installation position is known in advance through the antenna and the own position and the position information of the radio wave source Azimuth correction device that compares the azimuth with the map azimuth and corrects the error in the radio azimuth based on the difference.

An antenna having directivity, a directional control means for controlling the directional direction of the antenna, an azimuth detecting device for detecting the azimuth of the radio wave of the target from the reception intensity of the radio wave radiated from the target received by the antenna; G that can measure own position
PS device, communication means for receiving the position information of the radio wave emitting source having the position measuring device, radio wave direction obtained by the direction detecting device by receiving the radio wave of the radio wave emitting source through the aerial, position information of the own position and the radio wave emitting source And an azimuth correction device for comparing the map azimuth of the radio wave emission source obtained by the calculation with the azimuth direction and correcting an error in the radio wave azimuth based on the difference.

The azimuth detecting device of the radio wave emitting source is mounted on the moving body, and the azimuth correcting device holds a plurality of correction values according to the angle formed by the direction in which the radio wave emitting source is viewed from the moving body and the traveling direction of the moving body. Is what you do.

The azimuth correction device receives radio waves of a plurality of different frequencies emitted from a radio wave emission source via an antenna, and obtains a plurality of radio azimuths obtained by the azimuth detection device for each frequency, and a position and radio wave of the own position. It compares the map orientation of the radio wave emission source obtained from the position information of the emission source with the map orientation, and corrects the error of the radio wave orientation for each of a plurality of frequencies based on the difference.

The azimuth evaluation method for a radio wave emitting source according to the present invention receives a radio wave radiated from a target while controlling the directivity of an antenna having directivity, and detects a radio azimuth of the target from a change in the reception intensity. Direction detection procedure, self-position measurement procedure to measure own position, communication procedure to receive position information of radio wave emission source, map direction of radio wave emission source by calculating from position information of radio wave emission source and own position It includes an azimuth correction procedure of comparing the radio azimuth obtained by the azimuth calculation procedure and the azimuth detection procedure with the map azimuth of the radio wave emission source obtained by the azimuth calculation procedure, and correcting an error in the radio azimuth from the difference. And

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, the configuration of the azimuth evaluation device for a radio wave emission source according to the first embodiment of the present invention will be described with reference to the drawings. In the following drawings, the same reference numerals indicate the same or corresponding parts. In FIG. 1, reference numeral 101 denotes an azimuth evaluation device (hereinafter, referred to as an azimuth evaluation device) for a radio wave emission source according to the present invention. Reference numeral 1 denotes a directivity pattern unique to the antenna 2 of the azimuth evaluator 101, and 2 denotes an azimuth evaluator 1
The antenna 01 is provided with a directional control unit (not shown). Reference numeral 3 denotes an azimuth detecting device for detecting the azimuth of the target radio wave emission source. Reference numeral 5 denotes a GPS device for measuring the position of the azimuth evaluation device 101 (and, in some cases, the nose direction of the mounting base, not shown). Reference numeral 7 denotes a radar antenna of a known target 98 whose position is known in advance, and reference numeral 8 denotes a radar transmitting device that emits a radio wave from the radar antenna 7. Reference numeral 11 denotes a GPS satellite.

Next, the operation will be described. The exact position of the azimuth evaluator 101 is obtained by the GPS device 5 installed in the azimuth evaluator 101 based on the radio wave received from the GPS satellite 11. The position information of the direction evaluation device 101 is input to the direction correction device 6. On the other hand, since the position information of the known target 98 is known in advance, it is input to the azimuth correction device 6 from, for example, a keyboard (not shown). The azimuth correction device 6 calculates an accurate azimuth (map azimuth) of the known target 98 as viewed from the azimuth evaluation device 101, using the two pieces of input position information described above. This map direction is temporarily set to α. The radar signal output from the radar transmitter 8 of the known target 98 is transmitted by the radar antenna 7, received by the antenna 2 on the side of the azimuth evaluator 101, and detected by the azimuth detector 3 to determine the direction of arrival (radio azimuth) of the radio wave. Is done.
This radio wave direction is assumed to be β.

The map azimuth α calculated by the azimuth correction device 6 is the accurate azimuth of the target 7, and the difference (α−β) from the radio wave azimuth β obtained by the azimuth detection device 3 is the directional pattern 1. Since this is an azimuth orientation error due to disturbance, the azimuth orientation can be performed with high accuracy by storing this in a storage device (not shown) as correction data and using it for correction when locating the unknown target. That is, if the azimuth evaluation result of a certain target obtained by the azimuth detecting device 3 is A,
The true direction is A- (α-β). In the above description, it goes without saying that there may be a plurality of known targets 98.

In general, the correction value (α-β) changes depending on the apparent direction in which the target 7 is viewed from a mounting base (not shown) on which the azimuth evaluation device 101 is mounted. It is better to check (α−β) in all directions by changing the direction of the mounted base (for example, the nose direction of the mounted base if the aircraft is an aircraft) by 360 °. FIG. 2 shows an example of the correction value thus obtained. In the figure, 0 ° indicates the reference direction of the mounting base, for example, the nose direction. FIG. 2 shows 0 °, 45 °, 130 °, 180 °, 240 °, 3
The error is small in the six directions of 15 °, and the error is large in other directions.

Embodiment 2 Regarding the form in which the known target is a moving body, the configuration of the radio wave source azimuth evaluation device according to Embodiment 2 of the present invention will be described with reference to the drawings. In each of the following drawings, the same reference numerals as those in FIG. 1 indicate the same or corresponding parts, and a detailed description thereof will be omitted. In FIG. 3, reference numeral 102 denotes an azimuth evaluation device of the present invention. Reference numeral 1 denotes an inherent directivity pattern of the antenna 2, and reference numeral 2 denotes an antenna of the azimuth evaluation device 102, which includes a direction control unit (not shown). Reference numeral 3 denotes an azimuth detecting device for detecting the azimuth of the target radio wave emission source. Reference numeral 4 denotes a communication device of the azimuth evaluation device 101, reference numeral 5 denotes a GPS device, and reference numeral 6 denotes an azimuth correction device for correcting an azimuth measurement error due to disturbance of the directivity pattern 1.

Reference numeral 7 denotes a radar antenna of a known target 99 (moving body) used for correction, and reference numeral 8 denotes a radar transmitting device that emits radio waves from the radar antenna 7. 9 is a GPS device installed on the known target 99, and 10 is a known target 9
9 is a communication device installed in the communication device 9. 11 is a GPS satellite.

Next, the operation will be described. The exact position of the azimuth evaluator 102 is the installed GPS device 5,
Further, the exact position of the known target 99 is obtained by the GPS device 9 installed on the known target 99, based on the radio waves received from the GPS satellites 11, respectively. The position information of the direction evaluation device 102 is input to the direction correction device 6. Known goal 99
Is sent to the azimuth evaluation device 102 by the communication device 10 and the communication device 4 and is input to the azimuth correction device 6.
The azimuth correction device 6 calculates an accurate map azimuth of the known target 99 as viewed from the azimuth evaluation device 102 using the input two pieces of position information described above. This is temporarily set to α. The radar signal output from the radar transmitter 8 of the known target 99 is transmitted by the radar antenna 7, received by the antenna 2 on the side of the azimuth evaluator 101, and received by the azimuth detector 3.
Is used to locate the radio wave arrival direction (radio direction). This is assumed to be β.

The map azimuth α calculated by the azimuth correction device 6 is the accurate azimuth of the target, and the difference (α-β) from the azimuth β obtained by the azimuth detection device 3 is the azimuth due to the disturbance of the directivity pattern 1. Since the location error is a location error, it is stored in a storage device (not shown) as correction data, and is used for correction when locating the unknown target, whereby highly accurate orientation can be performed. That is, if the azimuth evaluation result obtained by the azimuth detecting device 3 of a certain target is A, the true azimuth is
A− (α−β). The communication of the position information is constantly performed, and even if the known target 99 moves, the position information is communicated and updated in real time, and an accurate correction is performed.

The correction value (α-β) is calculated by the direction evaluation device 1
As described in Embodiment 1, it is better to check all the apparent directions in which the target 7 is viewed from the mounting base (not shown) on which the target 02 is mounted. As a result, FIG. The data as shown is obtained.

Embodiment 3 The shape of directivity pattern 1 is
The correction value measured at a certain frequency is not correct at a different frequency because the value changes depending on the frequency of the radio wave. In the third embodiment, in order to prevent the azimuth accuracy from deteriorating due to the frequency change and perform more accurate azimuth orientation, the radar transmitting device 8 of the known target 99 transmits a plurality of frequencies simultaneously or by switching. A frequency transmitter 81 is provided, and the frequency transmitted by the known target 99 is determined by the azimuth evaluator 1
A large number of frequency ranges to be received by the frequency band 03 are prepared for each of predetermined frequency bands, and correction data is obtained for each of the divided frequency bands. In FIG. 4, 3 to 6 have the same configuration as in the first embodiment, and 13 is a frequency-dependent correction device that corrects the azimuth for each frequency band received by the azimuth evaluation device 103.

Next, the operation will be described. The correction data calculated by the azimuth correction device 6 is input to the frequency discriminating and correcting device 13 and held as correction data for each frequency.
FIG. 5 shows an example of the correction data stored in this way. In FIG. 5, the vertical axis indicates the correction value, the horizontal axis indicates the angle, and the depth direction indicates the frequency band. When the azimuth estimating device 103 receives the radio wave of the unknown target, the frequency correction device 13 selects correction data corresponding to the frequency of the unknown target, corrects the azimuth, and performs more accurate azimuth localization.

Embodiment 4 The above-described azimuth estimating apparatus for a radio wave emitting source according to the present invention will be described as an azimuth estimating method with reference to the flowchart in FIG. In FIG. 6, in step S1, the radio wave radiated from the target 7 is received while controlling the directivity of the antenna 2 having directivity, and the radio wave direction of the target 7 is detected from a change in the reception intensity (azimuth). Detection procedure). Next, in step S2, the self-position is measured by the GPS device 5 (self-position measurement procedure).
Next, in step S3, position information of the radio wave emission source 7 is received (communication procedure). In this case, it does not matter how the position information of the radio wave emission source is obtained. Next, in step S4, the map orientation of the radio wave emission source is obtained by calculating from the position information of the radio wave emission source 7 and the own position (azimuth calculation procedure). Next, in step S5, the radio wave direction obtained by the direction detection procedure is compared with the map direction of the radio wave emitting source 7 obtained by the calculation procedure, and a correction value for correcting an error in the radio direction is obtained from the difference. This correction value is stored in a storage device (not shown) (azimuth correction procedure). Thus, when a new unknown target radio wave is received, the obtained radio azimuth is corrected by the stored correction value, thereby enabling accurate azimuth evaluation.

[0024]

As described above, according to the radio wave source azimuth evaluation device of the present invention, the radio wave of the fixed radio wave source that is in advance in the map direction is received, and the radio direction is measured. Since the radio wave direction is corrected based on the difference between the map direction and the radio wave direction, there is an effect that a more accurate direction location device can be obtained.

Also, a GPS device is mounted on a moving radio wave emission source, its position information is obtained by communication means to calculate its map direction, and the radio wave from the radio wave emission source is received to determine its radio direction. Since the measurement and the comparison between the map direction and the radio wave direction are performed and the radio wave direction is corrected based on the difference between them, there is an effect that a more accurate direction locating device can be obtained.

In addition, since the azimuth correction is performed according to the direction in which the radio wave emission source is viewed from the mounting base on which the radio wave emission source azimuth evaluation device is mounted, there is an effect that a more accurate azimuth localization device can be obtained.

Further, since the azimuth correction determines the correction value according to the frequency, there is an effect that a more accurate azimuth locating device can be obtained.

The azimuth evaluation method of the radio wave emission source according to the present invention is obtained by a azimuth calculation procedure for obtaining a map azimuth of the radio wave emission source by calculating from the position information of the radio wave emission source and the own position, and a azimuth detection procedure. The radio wave direction and the map direction of the radio wave emission source obtained by the direction calculation procedure are compared, and a direction correction procedure of correcting an error in the radio direction from the difference is included. There is an effect that can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an azimuth locating device according to Embodiment 1 of the present invention.

FIG. 2 is an explanatory diagram of a correction characteristic of FIG. 1;

FIG. 3 is a configuration diagram of a bearing locating device according to a second embodiment of the present invention.

FIG. 4 is a configuration diagram of an azimuth locating device according to Embodiment 3 of the present invention.

FIG. 5 is an explanatory diagram of a correction characteristic of FIG. 4;

FIG. 6 is a flowchart illustrating a bearing evaluation method according to a fourth embodiment.

FIG. 7 is a configuration diagram of a bearing locating device having a conventional configuration.

FIG. 8 is an explanatory diagram of a directivity pattern for explaining the problem of FIG. 7;

[Explanation of symbols]

1 directional pattern, 2 antenna, 3 direction detection device, 4 communication device, 5 GPS device,
6 azimuth correction device, 7 radar antenna, 8 radar transmission device, 9 GPS device, 10 communication device,
11 GPS satellites, 12 radio emission target,
13 frequency band correction device, 81 multiple frequency oscillator, 9
8, 99 Known targets (radiation source), 100, 101,
102, 103 Direction evaluation device for radio wave emission source.

Claims (5)

[Claims] An antenna having directivity, a directional control means for controlling a directional direction of the aerial, and an azimuth for detecting a radio azimuth of the target from a reception intensity of a radio wave radiated from the target received by the aerial. A detecting device, a GPS device capable of measuring its own position, a radio wave direction obtained by the direction detecting device by receiving a radio wave of a radio wave emitting source whose installation position is known in advance on the antenna, and positional information of the radio wave emitting source And a azimuth correction device for comparing an azimuth of the radio wave emission source obtained by calculation from the own position and the map orientation, and correcting an error of the radio azimuth from the difference. Rating device. 2. An antenna having directivity, directional control means for controlling the directional direction of the antenna, and an azimuth for detecting a radio azimuth of the target from the reception intensity of a radio wave radiated from the target received by the antenna. A detecting device, a GPS device capable of measuring its own position, a communication means for receiving position information of a radio wave emitting source having a position measuring device, and a radio wave of the radio wave emitting source received by the antenna and obtained by the azimuth detecting device. An azimuth correction device for comparing the radio direction and the map direction of the radio source obtained by calculating from the position information of the radio source and the own position, and correcting an error of the radio direction from the difference is provided. An azimuth evaluation device for a radio wave emission source. 3. An azimuth detecting device is mounted on a moving body, and the azimuth correcting device holds a plurality of correction values according to an angle between a direction in which the radio wave emission source is viewed from the moving body and a front direction of the moving body. The azimuth evaluation device for a radio wave emission source according to claim 1 or 2, wherein: 4. An azimuth correction device receives radio waves of a plurality of different frequencies emitted from a radio wave emission source via an antenna, and obtains a plurality of radio azimuths obtained by an azimuth detection device for each frequency; The method according to claim 1, further comprising: comparing a map direction of the radio wave source obtained from the position information of the radio wave source with a map direction of the radio wave source, and correcting an error in the radio wave direction for each of the plurality of frequencies based on the difference. The azimuth evaluation device for a radio wave emission source according to any one of claims 1 to 3. 5. An azimuth detecting procedure for receiving a radio wave radiated from a target while controlling the directivity of an antenna having directivity, and detecting a radio azimuth of the target from a change in the reception intensity. Self-position measurement procedure to measure the position information, communication procedure to receive the position information of the radio wave emission source, azimuth calculation procedure to obtain the map orientation of the radio wave emission source by calculating from the position information of the radio wave emission source and the own position, The radio wave azimuth obtained by the azimuth detection procedure, and the map azimuth of the radio wave emission source obtained by the azimuth calculation procedure is compared, and the azimuth correction procedure of correcting the error of the radio azimuth from the difference, Azimuth evaluation method of the radio emission source.