JP2000275285A - Coaxial connector for high-frequency measurement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coaxial connector for high-frequency measurement reducing the measurement error by a measuring instrument and capable of making high-precision measurement regardless of the shape of a measured object. SOLUTION: An outer contact conductor 12 is stretched in the axial direction to form a stretch section 12a, a measuring pin 14 notched at the tip section is inserted into the cylindrical center contact conductor 11, thus a coaxial connector 10 having a female structure can be connected to a calibration standard unit having a male structure. The terminal electrode of a measured object 20 can be connected to the center contact conductor 14 or the outer contact conductor 12 by crimping. When calibration is made by the calibration standard unit, various measurement of the measured object 20 can be conducted with high precision.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coaxial connector for connecting a measuring instrument such as a network analyzer and a calibration standard or a device under test in high frequency measurement.

[0002]

2. Description of the Related Art Conventionally, when measuring various characteristics of a device under test using a measuring instrument such as a network analyzer, a calibration standard (Calibr
Calibration of the measurement device using ation Standard) has been performed. This calibration operation is to obtain a measurement error caused by a measurement cable connecting the device under test and the measuring device at the time of measurement, thereby correcting the measuring device, and is performed prior to the measurement of the device under test. Generally, this measurement error has a great effect on the measurement value especially in a high frequency region, and therefore, a calibration operation for correcting this error is an important operation.

[0003] This calibration standard has predetermined characteristics. What represents this characteristic is called a defined value of the calibration standard. In the calibration, the characteristics of the calibration standard are measured using a measurement cable, and the measured value is compared with the defined value. Then, a correction value for calibration is calculated from the difference between the measured value and the defined value, and the measuring device is calibrated using the correction value for calibration. The measurement of the device under test is performed using a measuring cable at the time of calibration and a measuring instrument that has been calibrated. Thereby, various characteristics of the device under test can be measured with high accuracy. Here, the measurement is, for example, measurement of transmission / reflection characteristics of a high-frequency component or a high-frequency circuit.

[0004]

The connection terminals of the measuring instrument, the calibration standard and the measuring cable are usually coaxial. For example, it is an SMA type coaxial connector. Therefore, if the device under test is a surface mount component (Surfac
e Mount Device (hereinafter referred to as “SMD”) cannot be directly connected to a measuring instrument. For this reason, a transmission line converter is used to connect the SMD to the measuring device. This converter converts a coaxial transmission line into a microstrip line or a coplanar line. The SMD can be connected to a microstrip line or a coplanar line of the converter. Usually, the connection is made by crimping the SMD to a microstrip line or a coplanar line.

[0005] In the measurement using such a conversion tool, the measurement results include characteristics of the measurement cable and the conversion tool as errors. For example, consider measuring reflection characteristics.
Here, if the calibration operation is performed using the measurement cable and the calibration standard before the measurement, the connection surface on which the calibration is completed (this is referred to as a calibration surface) becomes the connection surface between the measurement cable and the converter. In this case, the signal supplied from the calibration surface reaches the SMD via the converter, and the reflected wave reflected from the SMD again reaches the calibration surface via the converter. As a result, the phase of the signal is shifted while the signal propagates through the converter, and a characteristic different from the reflection characteristic originally intended to be measured is observed. Therefore, it is necessary to calibrate the measuring instrument so as to eliminate a measurement error caused by the converter and the measuring cable, which are transmission lines.

However, the calibration standard also has a coaxial connection terminal, so that a measurement error of the converter cannot be excluded. That is, if the measurement cable and the calibration standard are used, the calibration surface can be used as the connection surface between the measurement cable and the converter, but the calibration surface cannot be used as the connection surface between the converter and the SMD. .

The present invention has been made in view of the above circumstances, and an object of the present invention is to perform measurement with high accuracy by reducing a measurement error caused by a measuring instrument regardless of the shape of an object to be measured. It is an object of the present invention to provide a coaxial connector for high frequency measurement that can be performed.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a high-frequency measurement coaxial connector for connecting a high-frequency measurement device to a calibration standard device or a device under test. Has a female structure that can be electrically connected to the male coaxial connector provided in the device, and is formed on the device when the device is brought into contact with the end face on the side facing the standard device. A center contact conductor and an external contact conductor are exposed on the end face such that the plurality of terminal electrodes are electrically connected to the center contact conductor or the external contact conductor, respectively.

According to the present invention, the calibration standard can be connected to the coaxial connector, and the terminal electrode of the device under test can be directly connected to the center contact conductor or the external contact conductor. Therefore, if the device under test is connected after the calibration standard is connected and the measuring device is calibrated, the device under test can be measured with high accuracy. That is, since the calibration surface can be used as the connection surface of the device under test, it is possible to eliminate the occurrence of measurement errors due to the intermediary of other connection tools.

According to a second aspect of the present invention, in the high frequency measuring coaxial connector according to the first aspect, a locking portion for locking an object to be measured is formed on an end face on a side facing the standard device. We propose one that is characterized.

According to the present invention, the connection between the device under test and the connector can be easily and reliably performed by the locking portion.

As a preferred embodiment of the present invention, according to the third aspect of the present invention, in the high-frequency measuring coaxial connector according to the second aspect, the locking portion projects in the axial direction from the edge of the external contact conductor. The present invention proposes a feature in which an object to be measured is locked to an edge of the overhang.

According to a fourth aspect of the present invention, in the high frequency measurement connector according to the second aspect, the locking portion has a step formed on the end surface, and the object to be measured is locked on the stepped surface. We propose one that is characterized.

According to a fifth aspect of the present invention, in the high-frequency measuring coaxial connector according to the fourth aspect, the end face is formed by two semicircular surfaces having a predetermined step.
The present invention proposes a feature in which a center contact conductor is formed on the step surface.

Further, in the sixth aspect of the present invention, the first to fifth aspects are provided.
In the above-mentioned coaxial connector for high-frequency measurement, there is proposed a coaxial connector characterized in that a conductor piece electrically connected to the center contact conductor and removably engaged with the center contact conductor is provided.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A high-frequency measuring coaxial connector according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an external perspective view of a coaxial connector for high frequency measurement,
2 is a perspective view illustrating an external appearance of the object to be measured, FIG. 3 is a perspective view illustrating a method of measuring the object to be measured, FIG. 4 is a cross-sectional view illustrating a method of measuring the object to be measured, and FIG. FIG. 6 is a perspective view illustrating a measuring method, FIG. 6 is a cross-sectional view illustrating another measuring method of an object to be measured, FIGS. 7 and 8 are cross-sectional views illustrating a calibrating method of a measuring instrument, and FIG. It is a figure explaining a measurement and calibration method using a device.

As shown in FIG. 1, a coaxial connector for high frequency measurement (hereinafter referred to as a coaxial connector) 10 is connected to a center contact conductor 11 which is conductively connected to a center conductor of a coaxial cable, and is connected to an outer conductor of the coaxial cable. An external contact conductor 12, an insulator 13 interposed between the center contact conductor 11 and the external contact conductor 12, and a measuring pin 14, which is a conductive piece that is conductively connected to and removable from the center contact conductor 11. I have. The coaxial connector 10 has a predetermined characteristic impedance value. This characteristic impedance value is preferably the same as that of a coaxial cable or other equipment in order to suppress unnecessary reflection. Generally, the characteristic impedance value is 50Ω
And 75Ω.

The center contact conductor 11 is formed of a metal member having a substantially cylindrical end and having a spring property, and has an inner surface serving as a contact surface. As a material of the center contact conductor 11, for example, brass, beryllium copper, or the like, which is plated with silver or the like as necessary, and has good conductivity is preferable.

The outer conductor 12 is made of a substantially cylindrical metal member having a common central axis with the center contact conductor 11, and has a thread formed on the outer peripheral surface. Further, the outer conductor 12 has an extended portion 1 whose end edge is extended in the axial direction.
2a is formed. The edge of the overhang 12a is a semicircular arc. That is, both side edges 12 of the overhang portion 12a
The line connecting b is formed so as to pass through the central axis of the coaxial connector 10. In other words, the end surface of the coaxial connector 10 has two semicircular surfaces formed with a step. As a material of the external contact conductor 12, for example, brass, beryllium copper, or the like, which is plated with silver or the like as necessary, and has good conductivity is preferable.

The insulator 13 determines the position of the center contact conductor 11, and the center contact conductor 11 and the external contact conductor 12
Are electrically insulated from each other. As a material of the insulator 13, for example, a fluororesin is used. The position of the center contact conductor 11 is determined, and the coaxial
Can have the above-mentioned predetermined characteristic impedance value, the insulator 13 can be unnecessary in some cases.
In this case, the center contact conductor 11 and the outer contact conductor 12 are electrically insulated by air.

The measuring pin 14 is made of a conductive member which can be electrically connected to the center contact conductor 11.
It is formed in a substantially cylindrical shape so as to be in contact with the inner surface. One end of the measuring pin 14 is cut out in a semi-cylindrical shape. Thus, when the measurement pin 14 is inserted inside the center contact conductor 11, the cutout section 1 of the measurement pin 14 is placed on a line connecting the both side edges 12b of the overhang portion 12a of the external contact conductor 12.
4a is arranged.

As described above, the coaxial connector 10 according to the present embodiment has the structure of a female coaxial connector. Therefore, if the dimensions and the like of the center contact conductor 11 and the external contact conductor 12 are set so as to engage with the male-type connector of the calibration standard device or the like, the male-type connection after the measurement pin 14 is removed. Can be connected to the container.

The coaxial connector 10 can directly connect a device under test such as a multilayer filter. FIG. 2 shows a multilayer filter as an example of the device under test 20. The device under test 20 includes a plurality of terminal electrodes 21 formed from the side surface to the upper surface and the lower surface. Three terminal electrodes 21 are formed on both side surfaces at predetermined intervals, and the terminal electrode 21a at the center is a signal terminal, and the other terminal electrodes 21b are each for grounding.

To connect the device under test 20 such as a laminated filter to the coaxial connector 10, as shown in FIGS. 3 and 4, the side of the device under test 20 is pressed against the end face of the coaxial connector 10. Just do it. Specifically, the notch section 14a of the measuring pin 14 contacts the signal terminal electrode 21a of the device under test 20, and the external contact conductor 12 is connected to the ground terminal electrode 21b.
Arrange so that it contacts. Here, since the edge of the device under test 20 is locked by the protruding portion 12a of the external contact conductor 12, the connection between the device under test 20 and the coaxial connector 10 is reliable and easy. In addition, as shown in FIG. 5, a device under test 30 such as a chip-shaped electronic component having external electrodes 31 formed at both ends can be similarly connected. Further, as shown in FIG. 6, a pair of coaxial connectors 10 and 10 'may be connected to both sides of the device under test 20 such as a laminated filter by inverting and pressing upside down.

Further, in this coaxial connector 10, as shown in FIGS. 7 and 8, a pair of coaxial connectors 10 and 10 'are provided.
Can be connected to each other. In this case, a connection pin 15 made of a conductive member that fits inside the center contact conductor 11 is used, and this connection pin 15 is inserted into both the center contact conductors 11 and 11 ′ of the coaxial connectors 10 and 10 ′. I do. As a result, the center contact conductors 11 and 11 'are electrically connected to each other. The external contact conductors 12 and 12 'are connected to each other by overlapping the end faces of the coaxial connectors 10 and 10'. Here, the coaxial connector 1
0 and 10 'are the external contact conductors 1 with the overhangs 12a and 12a' of the external contact conductors 12 and 12 'facing each other.
The portions 2 'and 12 are opposed to each other so as to come into contact with portions where the overhang portions are not formed. That is, they are rotated by 180 ° relative to the central axis to face each other. This ensures that the external contact conductors 12 and 12 'are connected to each other. Such a connection is effective at the time of a calibration operation performed prior to the measurement of an object to be measured in a measurement system including the coaxial connector 10 and a coaxial cable connecting the coaxial connector 10 and the measuring device.
That is, by such a connection, the THR of the measurement system is changed.
OUGH characteristics can be obtained.

The high frequency measurement using such a coaxial connector 10 will be described with reference to FIG. In this measurement, as shown in FIG. 9, a coaxial cable 50 having a coaxial connector 10 at one end and a coaxial connector 51 connectable to the measuring device 60 at the other end is connected to a measuring instrument 60 such as a network analyzer. This is performed by connecting to the vessel 61.

First, prior to the measurement of the device under test 20 such as a laminated filter, the measurement system including the coaxial connector 10, the coaxial cable 50, and the coaxial connector 51 is calibrated. Here, the center contact conductor 11 of the coaxial connector 10 is conductively connected to the center conductor of the coaxial cable 50, and the external contact conductor 12
Is electrically connected to the outer conductor of the coaxial cable. Also,
For this calibration, a calibration standard 70 having a male connector 71 is used. The calibration standard 70 is usually provided together with the measuring instrument 60, and is referred to as “LOAD”.
There are three types, "OPEN" and "SHORT".

This calibration is performed by connecting the male connector 71 of the calibration standard 70 directly to the coaxial connection 10. In such a connection state, various characteristics are measured, and a correction value for calibration is calculated from the measured values and the characteristics (definition values) of the standard device 70, thereby calibrating the measuring device 60. In addition,
As described above with reference to FIGS. 7 and 8, in the present invention,
When measuring the THROUGH characteristics, by connecting the coaxial connectors 10 directly to each other without connecting the standard device,
Accurate characteristics can be obtained.

After the calibration of the measuring device 60 is completed in this way, the calibration standard device 70 is removed, and the device under test 20 such as a laminated filter is directly connected to the coaxial connector 10. Should be performed. Note that the connection here is as described above with reference to FIGS. 3 to 6, and the device under test can be directly connected without using members such as a coaxial connector and a transmission converter.

As described above, according to the coaxial connector 10 according to the present embodiment, the coaxial connector 10 is
0 can be connected, and the terminal electrode 21 of the device under test 20 can be directly connected to the center contact conductor 11 or the external contact conductor 12. Therefore, after the calibration standard 70 is connected and the measuring device 60 is calibrated,
Is connected, the measurement of the DUT 20 can be performed with high accuracy. In other words, since the calibration surface can be used as the connection surface of the device under test 20, it is possible to eliminate the occurrence of measurement errors caused by intervening other connection tools. This is particularly effective when measuring a surface mount component (SMD).

Next, a method of manufacturing the coaxial connector 10 will be described with reference to FIGS. 10 to 1
2 is a cross-sectional view illustrating a method for manufacturing a coaxial connector.

As described above, the coaxial connector 10 has a structure as a female coaxial connector. The coaxial connector 10 can be connected to a male connector included in the calibration standard. Therefore, the coaxial connector 10 may be manufactured by processing a normal female coaxial connector that can be engaged with the male connector of the calibration standard device. For example, a female coaxial connector of SMA type or 3.5 mm type PC (Precision Connector) is used. In the present embodiment, an SMA type connector is used.

To manufacture the coaxial connector 10, as shown in FIG. 10, the tip of the SMA female coaxial connector 80 is cut off. In this cutting, first, the coaxial connector 80 is cut at a position at a predetermined distance from the tip, and only the upper half is cut so that the edge of the external contact conductor becomes semicircular. By connecting in this manner, a connector 80 as shown in FIG. 11 is obtained. Finally, as shown in FIG. 12, the coaxial connector 10 is obtained by inserting the measuring pin 14 into the center contact conductor of the connector 80.

In this embodiment, the female coaxial connector is manufactured by processing an SMA type coaxial connector, but the present invention is not limited to this. For example, as described above, a PC 3.5 mm type or another standard / type may be used. For example, C01 type (N type), C02
Type (BNC type), C03 type (C type), C04 type (HN
Type), C11 type, UHF type, S type, C05 type (SMB
Type), TNC type, and the like.

In the present embodiment, the coaxial connector 10
Has a coaxial cable connected to one end, but the present invention is not limited to this. For example, a relay connector having a female structure at both ends or a relay connector having a female structure at one end and a male structure at the other end may be used.

In this embodiment, the multilayer filter and the chip-shaped electronic component are shown as examples of the device under test, but the present invention is not limited to this. That is, as long as it has a connection terminal electrode and can contact the center contact conductor 11 and the external contact conductor 12 of the coaxial connector 10, the shape and the type are not limited. In this case, the shape of the measuring pin 14 may be processed according to the measured object. It goes without saying that a circuit module having a coaxial connector can be connected.

[0037]

As described in detail above, according to the present invention,
The calibration standard can be connected to the coaxial connector, and the terminal electrodes of the device under test can be directly connected to the center contact conductor or the external contact conductor. Therefore, if the device under test is connected after the calibration standard is connected and the measuring device is calibrated, the device under test can be measured with high accuracy.
That is, since the calibration surface can be used as the connection surface of the device under test, it is possible to eliminate the occurrence of measurement errors due to the intermediary of other connection tools.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a coaxial connector for high frequency measurement.

FIG. 2 is an external perspective view of an object to be measured.

FIG. 3 is a perspective view illustrating a method of measuring an object to be measured.

FIG. 4 is a cross-sectional view illustrating a method for measuring an object to be measured.

FIG. 5 is a perspective view for explaining another method for measuring an object to be measured.

FIG. 6 is a cross-sectional view illustrating another method for measuring an object to be measured.

FIG. 7 is a cross-sectional view illustrating a method of calibrating a measuring instrument.

FIG. 8 is a cross-sectional view illustrating a method of calibrating a measuring instrument.

FIG. 9 is a diagram illustrating a measurement and calibration method using a coaxial connector for high frequency measurement.

FIG. 10 is a sectional view illustrating a method of connecting a coaxial connector.

FIG. 11 is a sectional view illustrating a method of connecting a coaxial connector.

FIG. 12 is a sectional view illustrating a method of connecting a coaxial connector.

[Explanation of symbols]

10 ... coaxial connector for high frequency measurement, 11 ... center contact conductor,
12: external contact conductor, 13: insulator, 14: measuring pin,
15 Connection pins, 20, 30 DUT, 21, 31 ...
Terminal electrode, 50: coaxial cable, 60: measuring instrument, 70:
Standard measuring instrument, 71: male connector, 80: coaxial connector

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01R 17/12 Z

Claims (6)

[Claims] 1. A high-frequency measuring coaxial connector for connecting a high-frequency measuring instrument to a calibration standard or an object to be measured, wherein the male high-frequency coaxial connector provided on the standard is electrically connectable. Having a female structure, a plurality of terminal electrodes formed on the DUT when the DUT is brought into contact with the end face on the side facing the standard device are electrically connected to the center contact conductor or the external contact conductor, respectively. A coaxial connector for high frequency measurement, wherein a center contact conductor and an external contact conductor are exposed on the end face so as to be connected. 2. The coaxial connector for high-frequency measurement according to claim 1, wherein a locking portion for locking an object to be measured is formed on an end face on a side facing the standard device. 3. The device according to claim 2, wherein the locking portion projects from an edge of the external contact conductor in the axial direction, and locks an object to be measured at an edge of the projection. Coaxial connector for high frequency measurement. 4. The coaxial connector for high-frequency measurement according to claim 2, wherein said locking portion has a step formed on said end face, and locks an object to be measured on said stepped surface. 5. The high-frequency measuring device according to claim 4, wherein the end face is formed by forming two semicircular surfaces with a predetermined step, and a center contact conductor is formed on the step surface. Coaxial connector. 6. The coaxial connector for high-frequency measurement according to claim 1, further comprising a conductor piece that is electrically connected to and detachably engages with the center contact conductor.