JPH11174102A - Y-shaped tem cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a Y-shaped TEM cell which can optimize utilization of a test space, by a method wherein three internal conductors are provided in a test region, the support base of an object to be tested is made rotatable and three N-type connectors in a coaxial connector joint region are connected, in a taper region, to both ends of the test region. SOLUTION: N-type connectors 5 to 7 are connected to a body in a coaxial connector joint region 3 via a taper region 2 from a test region 1 in which an object to be tested is placed. The N-type connectors 5 to 7 are connected to respective left ends of a first internal conductor 11 to a third internal conductor 13 in the test region 1, and N-type connectors 8 to 10 are connected to their right ends. In addition, a gate is provided in the test region 1 in addition to a third outside conductor 16 in the center, and the state of the object to be tested is observed from a shielding window. The object to be tested is fixed to, and arranged on, a rotatable support base 4, and a support base 19 supports the body as a whole so as to be freely movable. The second internal conductor 12 and the third internal conductor 13 are installed near an upper wall and a lower wall inside the third outside conductor 16, also the first internal conductor 11 is installed near a wall, and a wide and uniform region is ensured. As a result, the utilization degree of a test space can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
S) Y-type T that generates standard electromagnetic waves (plane waves) required for measurement such as electromagnetic interference (EMI), antenna correction, etc.
Regarding the EM cell.

[0002]

2. Description of the Related Art Generally, a conventional TEM (transverse electr
omagnetic) cell facilities at Crawford TEM cell, GTEM cell (Giga-Hertz TEM cell), TTEM
There are many types such as a cell (Triple TEM cell), a WTEM cell (Wire TEM cell), an improved GTEM cell, a TEM cell for automatic measurement, and a 6-terminal TEM cell, which can be roughly classified into two types.

That is, a GTEM cell (Giga-He)
rtz TEM cell), TTEM cell (Tripl
e TEM cell), WTEM cell (Wire TE)
M cell), an improved GTEM cell, etc., which have an input / output terminal on one side, such as a “one-end TEM cell”, a Crawford TEM cell, an asymmetric TEM cell, and a T for automatic measurement.
Like the EM cell and the 6-terminal TEM cell, it can be classified into “both ends TEM cell” having input / output terminals on both sides. Both of the above two types measure electromagnetic interference, measure electromagnetic immunity,
It is used for antenna correction, etc., but the former can only test in the far field, and the latter can support not only the far field but also the near field test, which are considered to be different from each other .

[0004] Both-end TEM cells can be further divided into two types. A TEM cell that supports only vertical polarization, such as a Crawford TEM cell, an asymmetric TEM cell, a variable impedance electromagnetic wave generator, and a 6-terminal TE.
It can be divided into M cells, TEM cells for automatic measurement, and TEM cells that also support vertical and horizontal polarization such as cylindrical TEM cells for rotation.

[0005] These devices further adjust the polarization by selecting the power supply of the internal conductor, such as a TEM cell for automatic measurement, a TEM cell for mechanical rotation such as a rotary cylindrical TEM cell, and a 6-terminal TEM cell. That is, it can be divided into a TEM cell that is electrically controlled. The latter can adjust only vertical and horizontal polarization, while the former can adjust arbitrary polarization. However, the latter is simpler in structure and easier to manufacture than the former. One end TEM cell that can electrically adjust vertical and horizontal polarization is TTEM
There are cells. This is possible because the TEM cell structure at both ends can be changed.

The six-terminal TEM cell can ensure a uniform field area much wider than that of the reference facility, and has a problem that the uniformity of the electromagnetic wave is very good, but the usefulness of the input power is reduced. On the other hand, the TTEM cell has the characteristic that the uniform field region is narrow and the uniformity of the electromagnetic wave is low, but has the characteristic that the input power is more useful than the six-terminal TEM cell.

In addition, both of these require that the structure of the outer conductor cross-section be maintained square to provide maximum uniformity. For this reason, when measuring electromagnetic resistance, electromagnetic interference, and the like for various electronic devices having a small width and a high height such as a portable horn, a wireless device having a dipole and a monopole antenna, various computer devices, and a refrigerator having a high width,
Existing facilities have a problem that a larger facility is required because the space utilization of the test area is low.

The size of the TEM cell at both ends is inversely proportional to the available frequency. For this reason, there is a problem that if the spatial utilization of the test area is low, the usable frequency band becomes narrow to that extent. Furthermore, when all products must be measured, such as sensitivity and correction measurement of wireless devices such as pagers and portable horns, it is necessary to secure a large amount of facilities and a very large work space. There is a problem.

[0009]

SUMMARY OF THE INVENTION Accordingly, the present invention provides two internal conductors for generating a vertically polarized standard electromagnetic wave so as to solve the above-mentioned problems. It is an object of the present invention to provide a Y-type TEM cell having high uniformity in both vertical and horizontal polarizations and optimizing utilization of a test space.

In order to achieve the above object, the present invention provides a device for supporting a test object so that the internal conductor is composed of three upper and lower side surfaces and can be rotated like a rotary table while fixing the test object. A test area with a table, 3
It is characterized by comprising a joint region of the coaxial connector on which the N-type connectors are mounted, and a tapered region connected to both ends of the test region so that the coaxial connector is mounted.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings.

FIGS. 1 to 4 are diagrams showing the configuration of a Y-type TEM cell according to the present invention.

As shown in FIGS. 2 and 3, when the structure of the present invention is largely divided, a test area 1 and a tapered area 2 where an object to be examined is placed, and a coaxial connector connecting a coaxial cable connector and a main body. It can be divided into an eye region 3 and a longitudinal region for longitudinally transmitting the transmitted electromagnetic wave.
At this time, the test area 1 is the first inner conductor 1 where the left end first N-type connector 5 and the right end first N-type connector 8 are connected.
1, a second inner conductor 12 in which the left end second N-type connector 6 and the right end second N-type connector 9 are connected, a third inner conductor 13 in which the left end third N-type connector 7 and the right end third N-type connector 10 are connected, 3 The external conductor 16, the gate 20 (FIG. 1), the shielding window 21 (FIG. 1) for observing the state of the object to be inspected, the support 4 on which the object to be inspected is fixed and the whole body are supported and movable. It is composed of a support 19 designed as follows.

In the side sectional view of the present invention shown in FIG.
The second inner conductor 12 and the third inner conductor 13 are installed near the upper and lower walls in the center third outer conductor 16 to secure a wider uniform field area, and the first inner conductor 11 is also installed near the outer conductor wall. , To ensure a wider uniform field area. However, the closer the inner conductor is to the outer conductor wall, the wider the uniform field region becomes, but on the other hand, there is a characteristic that the uniformity of the electromagnetic wave becomes worse.

Further, the first, second and third inner conductor structures are all characterized by the characteristic impedance (typically 50
Ohms), the width of the inner conductors must be determined once the positions of the first, second and third inner conductors 11, 12, and 13 are fixed. Also,
Since the structure having the characteristic impedance of 50 ohms is changed depending on the power supply method,
Unlike the first inner conductor 11, the three inner conductors 12 and 13 have a characteristic impedance matching structure by odd-mode power supply (feeding so that the magnitude of the input voltage is the same and the phase difference is 180 degrees). decide.

The test object support table 4 installed in the test area 1 is rotatable by separately mounting a disk 22 on a disk support plate 24, and the test object is mounted on the disk 22. A bearing 23 is provided between them for smooth rotation. DUT support 4, disk support 24 and disk 2
Numeral 2 is made of a nonconductive material having a low dielectric constant, such as Teflon, in order to minimize distortion of the internal standard electromagnetic wave.
The bearing 23 is made of a hard material such as ceramic which is a non-conductive material, and is graduated so that the rotating state and the position of the test object can be easily grasped.

In the joint region 3 of the coaxial connector, a first outer conductor 14 is provided for connecting the coaxial cable and the main body. A fourth inner conductor 25 is provided inside the first outer conductor 14 and is connected to the inner conductor at the end of the tapered region 2.
6 was inserted and fixed. These structures are all designed to maintain impedance matching.

The tapered region 2 comprises a second outer conductor 15 and first, second, third inner conductors 11, 12, and 13,
This is a tapered region for maintaining the size of the test object region. Further, the tapered region 2 is kept short within a range where there is no distortion of the electromagnetic wave. This is because the longer the length, the longer the effective length and the lower the resonance frequency.

5 to 8 are electric field value deviation distribution diagrams of the TEM cell, and FIG.
It is a 50-ohm electric field value deviation distribution figure which has a 2m cross section size. FIG. 6 shows a conventional 6-terminal TEM cell of 1.2mx1.
It is a 50-ohm electric field value deviation distribution figure which has a 2m cross section size. FIG. 7 shows a 1.2 m Y-type TEM cell according to the present invention.
FIG. 8 is a distribution diagram of electric field value deviation of 50 ohms having a cross-sectional size of x1.2 m. FIG.
It is a 50 ohm electric field value deviation distribution figure which has a 2mx1.2m cross section size. The result on the right side of each figure is the result of horizontal polarization formation, and the result on the left side is the result of vertical polarization formation. FIGS. 5 to 8 show electric field distribution diagrams normalized with respect to the results measured using the isotropic electric field probe at the center point. The uniform field region of the Y-type TEM cell according to the present invention is large. I understand.

In particular, FIG. 8 shows a Y-type TEM for measuring electromagnetic wave immunity and obstacles to a test object having a high height and a narrow width.
FIG. 3 is a 50 ohm electric field value deviation distribution diagram having a 1.2 mx 1.2 m cross-sectional size of the cell.
Unlike the terminal TEM cell, in which the uniformity of the internal electromagnetic wave is low when the cross-sectional structure cannot maintain a square, the Y-type TEM cell according to the present invention has very stable uniformity in both vertical and horizontal polarization. It turns out that there is. At this time, the size of the uniform field region was 0.33 mx 0.467 m, and when the total incident power was 2 Watt, the vertical electric field was measured as 6.11 V / m from the center and the horizontal electric field was measured as 9.14 V / m. Measurement Results The Y-type TEM cell according to the present invention is suitable for measuring electromagnetic interference and immunity to a general test object having a small width and a high height, such as a refrigerator, a computer, and a portable horn.

The following Table 1 shows the size of the uniform field region of the conventional TEM cell and the Y-type TEM cell of 1.2 mx 1.2 m and the electric field strength at the center at the time of 2 Watt input.

[Table 1] TEM cell Size of uniform field region (m) Electric field strength at center (V / m) Horizontal polarization Vertical polarization TEM cell 0.24 x 0.24 7.42 7.42 6-terminal TEM 0.325x0.325 1.16 1.16 Y-type TEM cell 0.3x0.33 10.4 7.98 In Table 1, the size of the uniform field region of the conventional TTEM cell is 0.24mx0.24m, Existing 6-terminal TE
The M cell is 0.325x0.325m and the Y cell according to the present invention
The type TEM cell was found to be 0.3mx0.33m. It has been found that the Y-type TEM cell according to the present invention has a slightly smaller uniform field area than the 6-terminal TEM cell, but is wider than the conventional TTEM cell. Further, as shown in Table 1, when the same incident power (2 Watt) is maintained, the electric field value at the center of the uniform field region is the lowest in the 6-terminal TEM cell, but the highest in the Y-type TEM cell according to the present invention. It turns out. That is, the Y-type TEM cell can generate high electromagnetic waves with low power.

[0023]

As described above, the Y-type TEM according to the present invention is used.
The cell enhances the usefulness of the incident power, can generate a high standard electromagnetic wave even with a small incident power, improves the uniformity of the electromagnetic wave, enables precise electromagnetic wave immunity, electromagnetic interference and correction, and receiver sensitivity measurement. Rather than mobile phones, wireless devices with dipole and monopole antennas, various computer equipment, refrigerators, etc. In addition, it is possible to produce models that increase the degree of utilization of the test space.

A technique for increasing the space utilization of the test area is very important from the viewpoint of frequency characteristics. This is because the smaller the cross section of the test area, the higher the cutoff frequency and the usable frequency band can be increased. As a result, the Y-type TEM cell has the effect of considerably increasing the usable frequency band as compared with existing facilities.

[Brief description of the drawings]

FIG. 1 is a perspective view of a Y-type TEM cell according to the present invention.

FIG. 2 is a front sectional view of a Y-type TEM cell according to the present invention.

FIG. 3 is a plan sectional view of a Y-type TEM cell according to the present invention.

FIG. 4 is a side sectional view of a Y-type TEM cell according to the present invention.

FIG. 5 is a 50 ohm electric field value deviation distribution diagram having a 1.2 mx 1.2 m cross-sectional size of a conventional TTEM cell.

FIG. 6 is a 50 ohm electric field value deviation distribution diagram having a 1.2 mx 1.2 m cross-sectional size of a conventional 6-terminal TEM cell.

FIG. 7 shows a 1.2 mx 1.
The distribution map of the electric field value deviation of 50 ohms having a cross section size of 2 m.

FIG. 8 shows 1.2 mx 1.
The electric field value deviation distribution figure of 50 ohm which has a 6-m section size.

[Explanation of symbols]

1: Test area 2: Tapered area 3: Coaxial connector joint area 4: Test object support base 5: Left end first N-type connector 6: Left end second N-type connector 7: Left end third N-type connector 8: Right end first N-type connector 9: Right end second N-type connector 10: Right end third N-type connector 11: First inner conductor 12: Second inner conductor 13: Third inner conductor 14: Left end first outer conductor 15: Left end second outer conductor 16: Center first 3 outer conductor 17: right end first outer conductor 18: right end second outer conductor 19: support base 20: gate 21: shielding window 22: disk 23: bearing 24: disk support plate 25: fourth inner conductor 26: dielectric body

Claims (6)

[Claims] 1. A test area in which an inner conductor is composed of three parts, upper and lower, and a side surface, and a test object support base is provided so that the test object can be rotated like a rotary table while fixing the test object. A Y-type TEM cell, comprising: a joint region of a coaxial connector on which three N-type connectors are mounted; and a tapered region connected to both ends of the test region so that the coaxial connector is mounted. 2. The Y-type TEM cell according to claim 1, wherein each of the three coaxial connectors is connected to each of the three N-type connectors. 3. The internal conductor according to claim 1, wherein two of the three internal conductors are formed so as to face each other, and another internal conductor is orthogonal to the two internal conductors. A TEM cell characterized by being formed as follows. 4. The Y-type TEM cell according to claim 1, wherein the inner conductor on the side surface has a greater distance from an outer wall than other upper and lower inner conductors. 5. The Y-type TEM cell according to claim 1, wherein the support is disposed between the upper and lower inner conductors. 6. The disk according to claim 1, wherein the support table supports a test object and is rotatable and separated, a disk support plate formed below the disk, the disk and the disk. A Y-type TEM cell formed between support plates and including a bearing for smooth rotation.