JP2003315396A - Electromagnetic wave measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform accurate measurement by excluding disturbance. <P>SOLUTION: An absorption unit 5 including an electric wave absorber, and covering a receiving face of an unselected opposed antenna 2 among a plurality of opposed antennas 2, is mounted. An opening part 5a as a non-absorption part is located oppositely to the selected opposed antenna 2 by the rotation of the absorption unit 5 by an absorption unit rotating mechanism 6, to receive the radiated power from a measured matter 7. The opposed antennas 2 are independently rotated by the antenna rotating mechanism 1, and the direction of polarized wave of the selected opposed antenna 2 and that of the unselected opposed antenna 2 are perpendicular to each other. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic wave measuring device for measuring unnecessary electromagnetic waves radiated from electronic equipment, radiation characteristics of antennas, and the like.

[0002]

2. Description of the Related Art As shown in FIG. 5, a conventional electromagnetic wave measuring apparatus has a plurality of counter antennas 52 arranged so as to surround an object to be measured 57 and a plurality of high frequency cables 53 output from the counter antennas 52. And a rotary table 58 for rotating the DUT 57 and a switching circuit 59 for processing the measurement data (for example, Japanese Patent Laid-Open No. 6-28908).
No. 1). The plurality of opposed antennas 52 are the objects to be measured 5
7 are arranged circumferentially so that the distances up to 7 are all equal to each other.

In order to measure the radiated electromagnetic wave from the object 57 to be measured, first, the switching circuit 59 is switched to sequentially select the opposing antennas 52. The electromagnetic waves for one round in the vertical plane direction, which is the arrangement direction of the opposing antennas 52, are measured by sequentially selecting in the circumferential direction around the center.
Then, such measurement is repeated while changing the angle of the rotary table 58. The measurement data (amplitude / phase) recorded by such measurement is processed by a predetermined radiation pattern estimation algorithm on the basis of the position of the opposing antenna 52 and the rotation angle of the turntable 58, and a predetermined display device as a radiation pattern. Is displayed in.

By the way, in the above publication, the opposed antenna 5 is used.
In order to reduce the disturbance of the measurement field due to the reflection of the high-frequency cable 53 connected to the second antenna 2, a configuration is proposed in which the radio wave absorber 55 is provided so as to surround the back side of the counter antenna 52. Further, a configuration is also proposed in which a rotating mechanism for individually rotating each of the counter antennas 52 is provided, and the angle of each of the counter antennas 52 is aligned with the polarization direction of the radio wave radiated by the DUT 57 by the rotation of the rotating mechanism. ing.

[0005]

However, in these conventional examples, since there are counter antennas other than the counter antenna that is selected and operating, radiation or reflection from those counter antennas that are not selected causes Disturbances in the measurement field and mutual coupling between adjacent opposing antennas occur, making it impossible to perform accurate measurements.

Therefore, an object of the present invention is to provide an apparatus capable of eliminating disturbances and performing accurate measurement.

[0007]

According to a first aspect of the present invention, a plurality of counter antennas are arranged toward an object to be measured as described in claim 1, and the counter antennas are selectively used. An electromagnetic wave measuring apparatus for measuring radiated power of an object to be measured, comprising: an electromagnetic wave absorber, comprising an absorption unit for covering the counter antenna not selected among the plurality of counter antennas. It is a measuring device.

According to a second aspect of the present invention, as described in claim 2, the plurality of opposed antennas are arranged in a ring around the object to be measured, the absorption unit is formed in a ring, and a radio wave is formed. A non-absorptive part not provided with an absorber is provided, and the non-absorptive part is interposed between at least one of the counter antenna and the DUT during use, and the absorption unit is centered on the DUT. The electromagnetic wave measuring device further includes a driving means for rotating the electromagnetic wave.

A third aspect of the present invention is an electromagnetic wave measuring apparatus as set forth in claim 3, wherein the absorbing unit includes a plurality of the non-absorbing portions at equal angular intervals.

A fourth aspect of the present invention is, as described in claim 4, the electromagnetic wave measuring device according to claim 3, wherein the non-absorption part is an odd number. .

According to a fifth aspect of the present invention, as described in claim 5, a plurality of opposed antennas are arranged toward the object to be measured,
In an electromagnetic wave measuring apparatus for selectively measuring the radiated power of the object to be measured by selectively using the opposed antennas, the plurality of opposed antennas are individually rotated with a straight line connecting each opposed antenna and the object to be measured as an axis. Opposed antenna drive means and opposed antenna control means for controlling the opposed antenna drive means are further provided, and the opposed antenna control means sets the polarization directions of the selected opposed antenna and the unselected opposed antenna different from each other. It is an electromagnetic wave measuring device characterized by making it possible.

According to a sixth aspect of the present invention, as in claim 6, there is provided the electromagnetic wave measuring device according to claim 5, wherein the polarization directions of the selected counter antenna and the non-selected counter antenna are different. It is an electromagnetic wave measuring device characterized by being orthogonal to each other.

According to a seventh aspect of the present invention, as described in claim 7, a plurality of opposed antennas are arranged toward the object to be measured,
In an electromagnetic wave measuring device that selectively uses the counter antenna to measure the radiated power of the object to be measured, a rotary base that rotates the object to be measured along an axis on the array surface of the counter antenna, and the rotation. The electromagnetic wave measuring device further includes a belt driving device that drives the table with an insulating material belt.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, the first of the present invention
The electromagnetic wave measuring apparatus according to the embodiment includes a plurality of opposed antennas 2 having an antenna rotating mechanism 1 as a polarization switching structure.
And a side absorption plate 4 that covers the side surface of the high-frequency cable 3 connected to each counter antenna 2, and a rotatable absorption that covers the front surface (side surface facing the DUT 7) of all counter antennas 2 that are not selected. The unit 5, the absorption unit rotation mechanism 6 for rotating the absorption unit 5, the rotary table 8 for rotating the DUT 7, the switching circuit 9 for switching the connection to the opposing antenna 2, and the calculator 10 for controlling the entire apparatus. And a receiver 11 for receiving a signal from the opposite antenna 2 selected by the switching circuit 9.

All the opposed antennas 2 are installed at equal intervals over the front circumference of the apparatus, and all of them are directed toward the object to be measured 7. The antenna rotating mechanism 1 is configured to rotate each counter antenna 2 by an arbitrary angle with a straight line connecting the counter antenna 2 and the DUT 7 as an axis.

The side absorption plate 4 is formed by forming two sets of known pyramid type electromagnetic wave absorbers made of rubber into a disc shape, the inner edge of which is adhered to the back side of the absorption unit 5, and the outer edge thereof. Is the free end.

The absorption unit 5 is a well-known rubber pyramid-type electromagnetic wave absorber, which covers the entire circumference except the opening 5a.
The absorption surface is arranged so as to face the DUT 7,
It is rotatably supported by a support (not shown) (for example, a support frame or a support roller) provided along the outer peripheral surface thereof.

The absorption unit rotating mechanism 6 comprises an endless belt 6a wound around the outer periphery of the absorption unit 5, a pulley for driving the endless belt 6a, and a motor (not shown). The endless belt 6a is in close contact with the outer peripheral side of the absorption unit 5, but is illustrated as being separated from the absorption unit 5 in FIGS. 1 to 4 for easy understanding.

The rotary table 8 has a mounting surface which is horizontal and a rotary shaft which is vertical, and is configured to be rotatable by an arbitrary angle by a rotary table driving device (not shown).

The calculator 10 comprises a well-known personal computer and is provided with a CPU, a RAM, a ROM, an input / output interface, a hard disk device and a display device. The output of the calculator 10 controls the switching circuit 9, the receiver 11, the antenna rotation mechanism 1, and the absorption unit rotation mechanism 6.

The switching circuit 9 selects one counter antenna 2 from the many counter antennas 2 according to the control signal from the calculator 10 and connects it to the receiver 11. Receiver 11
The amplitude and phase of the signal of each counter antenna 2 received by are input to the calculator 10, respectively. In the calculator 10, the rotation position of the absorption unit 5 by the absorption unit rotation mechanism 6 (an angle command to the absorption unit rotation mechanism 6 or an angle signal from the absorption unit rotation mechanism 6) and the angle of the turntable 8 (with respect to the turntable drive device). The radiation pattern is calculated based on a predetermined algorithm while taking into consideration the angle command or the angle signal from the rotary base driving device.

The antenna rotating mechanism 1 and the absorbing unit rotating mechanism 6 are controlled in synchronization with the operation of the switching circuit 9. Specifically, each antenna rotation mechanism 1 is individually controlled so that the polarization direction of the counter antenna 2 selected by the switching circuit 9 is orthogonal to the polarization direction of the other counter antenna 2. Further, the absorption unit rotation mechanism 6 is controlled so that the front side, which is the reception surface of the opposing antenna 2 selected by the switching circuit 9, is exposed from the opening 5 a when viewed from the DUT 7, and the absorption unit 5 is controlled by the absorption unit 5. Displace in the direction of rotation.

As described above, in the first embodiment, the absorption unit 5 that includes the electromagnetic wave absorber and covers the receiving surface of the counter antenna 2 that is not selected among the plurality of counter antennas 2 is provided. Radiation from the object 7 to the unselected counter antenna 2 is blocked by the absorption unit 5, and mutual coupling or reflection from the unselected counter antenna 2 to the selected counter antenna 2 can be effectively prevented.

Further, in the first embodiment, the opening 5a, which is the non-absorbing portion, is selected (or has been) by the rotation of the absorbing unit 5 by the absorbing unit rotating mechanism 6.
Since the radiated power from the device under test 7 can be received by being opposed to the opposing antenna 2-1, it is possible to obtain the intended effect of the present invention with a simple configuration. Further, in the first embodiment, since the absorption unit 5 has a ring shape, the opposing antenna 2 can be periodically selected by the constant speed intermittent rotation in one direction (for example, R direction in the drawing), and the operation of the absorption unit 5 is simplified. it can. Further, in the first embodiment, since the opposing antenna 2 and the high frequency cable 3 do not move while the absorption unit 5 rotates, the measurement conditions do not change, and highly accurate measurement is possible.

Further, in the first embodiment, the antenna rotating mechanism 1 as the counter antenna control means polarizes the selected counter antenna 2-1 and the non-selected counter antenna 2. Since the directions are different from each other, mutual coupling between the unselected counter antenna 2 and the selected counter antenna 2-1 can be prevented, and accurate measurement can be performed. Further, the installation interval of each opposing antenna 2 can be made smaller than λ / 2 (λ: wavelength), and a large number of opposing antennas 2 can be installed in close contact with each other, so that the measurement accuracy can be improved. Further, in the present embodiment, since the polarization directions of the selected counter antenna 2-1 and the non-selected counter antenna 2 are orthogonal to each other, this effect can be realized particularly suitably.

Further, in the first embodiment, each opposing antenna 2
Since the side absorption plate 4 that covers the side surface of the high-frequency cable 3 connected to is provided, the reflection from the high-frequency cable 3 can be suppressed.

Next, a second embodiment will be described. In FIG. 2, in the electromagnetic wave measuring apparatus of the second embodiment, the absorption unit 15 has three openings 15a as non-absorption parts, and the three openings 15a are equiangularly spaced with respect to the DUT 7 ( That is, they are arranged at 120 ° intervals. The remaining mechanical structure in the second embodiment is the same as that in the first embodiment, and therefore the same reference numerals are given and the description thereof is omitted.

In the second embodiment, the switching circuit 9 is controlled by the control signal from the calculator 10 to generate a large number of opposing antennas 2.
From the above, three opposing antennas 2 corresponding to the openings 15a are selected and sequentially connected to the receiver 11.

The antenna rotating mechanism 1 and the absorbing unit rotating mechanism 6 are controlled in synchronization with the operation of the switching circuit 9. Specifically, the polarization directions of the counter antennas 2-1 selected (selected) by the switching circuit 9 are orthogonal to the polarization directions of all the other counter antennas 2 during measurement. In addition, each antenna rotation mechanism 1 is individually controlled.
Further, the absorption unit rotation mechanism 6 is controlled so that the front side, which is the reception surface of the three opposing antennas 2-1 selected by the switching circuit 9, is exposed from the opening 15 a when viewed from the DUT 7, and the absorption unit rotation mechanism 6 is controlled. 15 is displaced in the rotational direction accordingly.

As described above, in the second embodiment, in addition to the same effects as in the case of the first embodiment, the absorption unit 15 is provided with the plurality of openings 15a at equal angular intervals. A plurality of opposing antennas 2 can be used without displacement, and the rotation angle of the absorption unit 15 required for selecting the opposing antennas 2 over the entire circumference can be made small (for example, 120 °).

Further, in the second embodiment, since the number of openings 15a is an odd number, the openings 15a are provided at equal angular intervals.
Do not face each other in the annular absorption unit 15, and it is possible to reduce the influence of each opposing antenna 2 from the opposing antennas 2 on the opposite sides of the DUT 7. Although the number of openings 15a is three in the second embodiment, the number of openings 15a may be an arbitrary odd number, and the same effect can be obtained.

Next, a third embodiment will be described. The electromagnetic wave measuring apparatus of the third embodiment shown in FIG. 3 includes a rotary table 38 for rotating the DUT 7 along an axis on the array surface of the opposing antennas (a vertical plane in the present embodiment), and a rotary table 3
8 is driven by the endless belt 39a in a direction intersecting the array surface of the opposing antennas. The opposing antenna and the high frequency cable are not shown in FIG.

The turntable 38 is rotatably supported on the upper ends of the non-rotating leg portions 38a, and the lower portions of the leg portions 38a branch to extend over the absorbing unit 5 and extend to the ground plane.
A belt groove (not shown) is formed on the outer edge of the rotary table 38, and an endless belt 39a is wound between the belt groove and a pulley (not shown) of the belt driving device 39. The rotary table 38 is driven by the power of a motor (not shown) of the belt driving device 39 via the endless belt 39a. The material of the endless belt 39a is preferably a material that has extremely little influence on radio waves, for example, an insulating material or a dielectric material such as polytetrafluoroethylene or silicone rubber. The remaining mechanical structure in the third embodiment is the same as that in the first embodiment, and therefore the same reference numerals are given and the description thereof is omitted.

In the third embodiment, in addition to the same effects as in the case of the first embodiment, since the rotary table 38 is laterally driven by the endless belt 39a, the belt driving device 39 is arranged outside the measurement area. Therefore, the influence of the structure for driving the turntable 38 on the measurement can be reduced. Further, the measurement with the opposing antenna can be performed from below the rotary table 38 in the vertical direction.

In the third embodiment, the endless belt 39
Although the rotary base 38 is driven from a direction crossing the array surface of the counter antenna by a, the endless belt 49a sandwiches the array surface of the counter antenna 2 as shown in FIG. 4 instead of such a configuration. Thus, the belt driving device 49 may be installed.

Although the opening 5a is used as the non-absorption portion in each of the above-described embodiments, the non-absorption portion need not be an opening as long as it is a member that has little influence on the electric field. In addition, in each of the above-described embodiments, the absorption units 5 and 1 are provided in order to selectively expose the counter antenna 2-1 used toward the DUT 7.
5 has been configured to rotate, but for the same purpose, for example, the electromagnetic wave absorber on the measurement surface side of each opposing antenna 2 can be individually opened and closed, and the electromagnetic wave absorption corresponding to the opposing antenna 2-1 used. The body may be selectively opened.
Further, in each of the above embodiments, the arrangement direction of the counter antennas 2 is annular, but the arrangement direction of the counter antennas 2 in the present invention is arbitrary, and may be linear or curved.
Alternatively, it may be in a matrix shape in which a plurality of opposing antennas 2 are arranged in the two-dimensional direction. In the latter case, it is preferable that the absorption unit is displaced on a plane or that the portion facing each opposing antenna is selectively opened. Further, in each of the above embodiments, the absorption unit 5,
Although 15 is a single unit, the absorption unit in the present invention may be divided into a plurality of units.

In each of the above-mentioned embodiments, the opposing antenna 2
Although the horn antenna is used as the antenna, the type of the opposing antenna in the present invention is arbitrary, and for example, a dipole antenna may be used. Further, in each of the above-described embodiments, the rotations of the absorption units 5 and 15 and the turntables 8 and 38 are controlled by the output of the calculator 10. However, the absorption unit and the turntable in the present invention may be manually operated, and such a configuration is also possible. It belongs to the category of the present invention.

[0038]

As described in detail above, in the first aspect of the present invention, the absorption unit which includes the electromagnetic wave absorber and covers the unselected opposing antenna among the plurality of opposing antennas is provided. Since radiation from the object to the counter antenna not selected is blocked, mutual coupling or reflection from the counter antenna not selected to the counter antenna selected can be effectively prevented.

In the second aspect of the present invention, the rotation of the absorption unit by the driving means causes the non-absorption part to face the selected opposite antenna, and the radiation power from the object to be measured can be received. With the configuration, the effect of the first aspect of the present invention can be obtained. Further, since the absorbing unit is annular, the opposing antenna can be periodically selected by rotating the absorbing unit in one direction.

In the third aspect of the present invention, since a plurality of non-absorbing portions are provided at equal angular intervals, a plurality of opposing antennas can be used at the same time, and the rotation angle of the absorbing unit required for selecting the opposing antennas over the entire circumference. Can be made smaller.

In the fourth aspect of the present invention, since the number of non-absorbing portions is an odd number, the non-absorbing portions provided at equal angular intervals do not face each other in the annular absorbing unit, and each opposing antenna sandwiches the DUT. The influence from the opposite antenna on the opposite side can be reduced.

In the fifth aspect of the present invention, since the opposite antenna control means makes the polarization directions of the selected opposite antenna and the unselected opposite antenna different from each other, it is selected as the unselected opposite antenna. Mutual coupling between opposing antennas can be prevented and accurate measurements can be performed.

In the sixth aspect of the present invention, the polarization directions of the selected opposing antenna and the non-selected opposing antenna are orthogonal to each other, so that the effect of the fifth aspect of the present invention can be realized particularly suitably.

In the seventh aspect of the present invention, since the rotary table is driven by the insulating material belt, the influence of the structure for driving the rotary table on the measurement can be reduced.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an electromagnetic wave measuring apparatus of a first embodiment.

FIG. 2 is a configuration diagram showing an electromagnetic wave measuring apparatus of a second embodiment.

FIG. 3 is a configuration diagram showing an electromagnetic wave measuring device of a third embodiment.

FIG. 4 is a configuration diagram showing a modified example of the electromagnetic wave measuring apparatus of the third embodiment.

FIG. 5 is a configuration diagram showing an electromagnetic wave measuring device before improvement according to the present invention.

[Explanation of symbols]

1 antenna rotation mechanism, 2,2-1,52 counter antenna, 3,53 high frequency cable, 4 side absorption plate, 5,
15 absorption unit, 5a, 15a opening, 6 absorption unit rotation mechanism, 7,57 DUT, 8,38,5
8 turntable, 9,59 switching circuit, 10 calculator, 11
Receiver, 39,49 Belt drive.

Claims (7)

[Claims] 1. An electromagnetic wave measuring device in which a plurality of opposed antennas are arranged toward an object to be measured and the radiated power of the object to be measured is selectively used by using the opposed antennas, and an electromagnetic wave absorber is included. An electromagnetic wave measuring apparatus comprising: an absorption unit that covers the unselected opposite antenna among the plurality of opposite antennas. 2. The electromagnetic wave measuring device according to claim 1, wherein the plurality of opposed antennas are annularly arranged with the object to be measured as a center, and the absorption unit is annularly formed. An absorber is provided without a non-absorptive part, and the non-absorptive part is interposed between at least one of the opposing antenna and the DUT during use, and the absorption unit is centered on the DUT. An electromagnetic wave measuring apparatus further comprising a driving unit for rotating the electromagnetic wave. 3. The electromagnetic wave measuring device according to claim 2, wherein the absorbing unit includes a plurality of the non-absorbing portions at equal angular intervals. 4. The electromagnetic wave measuring device according to claim 3, wherein the non-absorption part is an odd number. 5. An electromagnetic wave measuring apparatus in which a plurality of counter antennas are arranged toward a measured object and the radiated power of the measured object is measured by selectively using the counter antennas. Opposed antenna drive means for individually rotating the antenna about a straight line connecting each opposed antenna and the object to be measured, and an opposed antenna control means for controlling the opposed antenna drive means, and the opposed antenna control means, An electromagnetic wave measuring device characterized in that polarization directions of a selected counter antenna and a non-selected counter antenna are different from each other. 6. The electromagnetic wave measuring device according to claim 5, wherein polarization directions of the selected opposing antenna and the unselected opposing antenna are orthogonal to each other. 7. An electromagnetic wave measuring apparatus in which a plurality of opposed antennas are arranged toward a measured object, and the radiated power of the measured object is measured by selectively using the opposed antennas. An electromagnetic wave measuring apparatus further comprising: a rotary table that rotates along an axis on the array surface of the opposed antennas; and a belt driving device that drives the rotary table with an insulating material belt.