JP2016127378A - High-frequency substrate fixing jig and measuring method of characteristics of high-frequency substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fix a high-frequency substrate in a state where an impact on high-frequency characteristics is low, without causing deformation and cracking.SOLUTION: A high-frequency substrate fixing jig (1) includes: a jig substrate (11) having a suction hole (24), the upper end of the suction hole (24) being opened at an arrangement position of a high-frequency substrate (2) on the top surface thereof and the lower end being opened to the bottom surface thereof; and a suction pad (15) provided at a position of the lower end of the suction hole (24) on the bottom surface of the jig substrate (11) and connected to a suction apparatus.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a high-frequency substrate fixing jig and a method for measuring characteristics of a high-frequency substrate that are used when, for example, a high-frequency substrate including a planar high-frequency antenna is fixed to measure characteristics.

  In recent years, with the increase in speed of wireless communication, there has been a demand for higher performance of electronic devices that perform wireless communication. In addition, downsizing of electronic devices is progressing rapidly due to ease of carrying. Furthermore, the radio capacity due to communication is rapidly increasing, and the accompanying increase in the frequency and frequency of transmission signals is rapidly progressing. For this reason, the use frequency band of electronic devices cannot be handled only by the conventional microwave band (0.3 to 300 GHz), and is being expanded to millimeter waves (30 to 300 GHz).

  From such a background, there is a strong demand for higher performance of antennas mounted on electronic devices and higher characteristics of circuit elements, such as amplifiers, filters, switches, and power distributors, in front of the antennas. In particular, for antennas used for wireless communication, conductor loss and dielectric loss are significantly affected as the frequency increases. For this reason, the request | requirement of the low loss to elements, such as an antenna, is also increasing.

  As one method for realizing a reduction in antenna loss, it is conceivable to use a low-loss material such as a liquid crystal polymer or quartz glass as a material constituting the antenna. In particular, quartz as a substrate material has a dielectric loss tangent of 0.00025, which is significantly smaller than 0.003 of a liquid crystal polymer, and can greatly reduce dielectric loss.

  Quartz is highly light transmissive and can be mounted while confirming the substrate terminal even in a mounting method in which the substrate terminal cannot normally be confirmed from the top surface, such as when flip-chip mounting an IC or the like on the substrate. It has a merit. Therefore, the quartz substrate is very effective when constituting an element for a high frequency band such as a millimeter wave.

  By the way, for example, for a high-frequency substrate including a planar high-frequency antenna, characteristics are measured in a state where the high-frequency substrate is fixed at a predetermined measurement position of a high-frequency substrate fixing jig. On the other hand, since the quartz substrate has defects on the surface and inside, there is a stress distribution. Therefore, the high-frequency substrate including the quartz substrate has a problem that when a large external stress is applied, the stress distribution changes and is easily broken.

  Therefore, a method for mechanically fixing the quartz substrate without breaking it is required. For example, when a quartz substrate is fixed with a screw, high linearity is required for a screw hole formed in the quartz substrate. Further, when the screw comes into contact with the screw hole, there is a risk that stress is formed and the quartz substrate is destroyed. Therefore, a jig for mechanically fixing the quartz substrate without forming a screw hole in the quartz substrate is required.

  For example, Patent Document 1 includes a container-shaped case having a measurement substrate inside as a high-frequency substrate fixing jig, and a lid made of metal such as aluminum that is fixed on the case with a screw. A device measurement socket is disclosed. The lid portion is formed with a through hole that exposes the upper surface of the high-frequency device from the lid portion when the high-frequency device is housed in the case and the lid portion is closed.

  When measuring the characteristics of a high-frequency device using this device measurement socket, place the high-frequency device on the substrate in the case, screw the lid from the top of the high-frequency device to the case, and use the lid to The high frequency device is pressed onto the substrate. Thereby, the high frequency device is fixed in the case.

WO 00/04394 (released January 27, 2000)

  However, as in Patent Document 1, in the configuration in which the high-frequency device is pressed and fixed from above by the lid portion, since the lid portion exists on the high-frequency substrate, the lid portion affects the radiation characteristics of the high-frequency substrate. As a result, the characteristics cannot be measured accurately.

  Further, when measuring the characteristics of the high frequency substrate, the substrate may bend and the characteristics of the high frequency substrate may change, and the characteristics may not be measured accurately. Furthermore, if the substrate is a quartz substrate, there is a possibility of cracking.

  Therefore, the present invention provides a high-frequency substrate fixing jig and a method for measuring the characteristics of a high-frequency substrate that can fix the high-frequency substrate without causing deformation or cracking of the high-frequency substrate and having a low influence on the high-frequency characteristics. It is an object.

  In order to solve the above-described problems, a high-frequency substrate fixing jig according to the present invention is a high-frequency substrate fixing jig for fixing a high-frequency substrate whose characteristics are to be measured. An upper end is provided at a position where the high-frequency substrate is disposed on the upper surface and a lower end is opened on the lower surface, and a lower end of the suction hole on the lower surface of the jig substrate is provided to suck air. And a suction pad to which a suction device is connected.

  According to said structure, the high frequency board | substrate of the property measurement object is arrange | positioned in the arrangement position of the upper surface of a jig | tool board | substrate, for example, a measurement position. At the arrangement position, the upper end of the suction hole which is a through hole is opened, and the lower end of the suction hole is opened on the lower surface of the jig substrate. The suction pad is provided at the lower end of the suction hole on the lower surface of the jig substrate, and connects the suction device and the suction hole. In this state, when the suction device is operated, the lower surface of the high-frequency substrate on the jig substrate is sucked and fixed to the arrangement position on the jig substrate.

  As a result, in this high frequency substrate fixing jig, there is no member that affects the characteristics of the high frequency substrate on the high frequency substrate to be measured. Can be measured accurately.

  In addition, the suction operation of the suction device fixes the high-frequency substrate to the arrangement position on the jig substrate, so that the load applied to the high-frequency substrate is not deformed or cracked. It can be easily adjusted to a suitable load that can be fixed on top.

  Therefore, it is possible to fix the high frequency substrate in a state where the high frequency substrate is not deformed or cracked and the influence on the high frequency characteristics is low.

  In the above high-frequency substrate fixing jig, the jig substrate has an electromagnetic wave input hole that is a through hole, and an upper end of the electromagnetic wave input hole is an electromagnetic wave input portion of the high-frequency substrate at a position where the high-frequency substrate is disposed. A configuration in which a waveguide that is opened at an opposing position, a lower end is opened at a lower surface, and a measurement device for the high-frequency substrate is connected to a lower end position of the electromagnetic wave input hole on the lower surface of the jig substrate It is good.

  According to the above configuration, the high-frequency signal, that is, the electromagnetic wave output from the measuring apparatus is input to the electromagnetic wave of the high-frequency substrate disposed at the position of the jig substrate via the electromagnetic wave input hole of the waveguide and the jig substrate. Is input to the department.

  As a result, even when the electromagnetic wave input to the high frequency substrate is a high frequency wave such as a millimeter wave, transmission loss due to soldering or the like that occurs when a coaxial cable is used can be suppressed and the transmission loss can be reduced.

  The above high-frequency substrate fixing jig includes an L-shaped positioning member that positions the high-frequency substrate by contacting a first side of the high-frequency substrate and a second side adjacent to the first side. It is good also as a structure provided with.

  According to the above configuration, the high-frequency board is easily positioned at a predetermined arrangement position with the first side of the high-frequency board and the second side adjacent to the first side in contact with the positioning member. be able to.

  The method for measuring characteristics of a high-frequency substrate according to the present invention is a method for measuring characteristics of a high-frequency substrate in which a high-frequency substrate to be measured is fixed on a jig substrate, and the jig substrate has a suction hole which is a through hole. And the upper end of the suction hole is opened at the arrangement position of the high-frequency substrate on the upper surface, the lower end is opened on the lower surface, air is sucked from the lower end of the suction hole on the lower surface of the jig substrate, The high frequency substrate is fixed to the arrangement position, and the characteristics of the high frequency substrate are measured.

  According to said structure, there exists an effect similar to said high frequency board | substrate fixing jig.

  According to the configuration of the present invention, it is possible to fix the high frequency substrate in a state where the high frequency substrate to be measured is not deformed or cracked and the influence on the high frequency characteristics is low.

It is a perspective view which shows the state by which the high frequency board | substrate has been arrange | positioned at the high frequency board | substrate fixing jig of embodiment of this invention. 2A is a plan view of the state shown in FIG. 1, and FIG. 2B is a cross-sectional view taken along line AA in FIG. It is a top view which shows an example of the dimension of each part of the high frequency board | substrate fixing jig shown to (a) of FIG. 4A is a plan view showing the upper surface of the high-frequency substrate shown in FIG. 1, FIG. 4B is a plan view showing the lower surface of the high-frequency substrate, and FIG. 4C is the high-frequency substrate. It is a side view of a board | substrate. It is a schematic diagram which shows the structure of the characteristic measuring apparatus which is equipped with the high frequency board | substrate fixing jig shown in FIG. 1, and measures the characteristic of a high frequency board | substrate. It is a perspective view which shows the high frequency board | substrate fixing jig which concerns on the comparative example with respect to the high frequency board | substrate fixing jig shown in FIG. FIG. 7 is a cross-sectional view taken along line B-B in FIG. 6. It is a graph which shows the reflective characteristic of the high frequency board | substrate at the time of using the high frequency board | substrate fixing jig (Example) shown in FIG. 1, and the high frequency board | substrate fixing jig (comparative example) shown in FIG. It is a graph which shows the radiation characteristic of the high frequency board | substrate of the case where the high frequency board | substrate fixing jig (Example) shown in FIG. 1 is used, and the high frequency board | substrate fixing jig (comparative example) shown in FIG.

(Configuration of high-frequency substrate fixing jig 1)
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a state in which a high-frequency substrate is arranged on the high-frequency substrate fixing jig of the present embodiment. 2A is a plan view of the state shown in FIG. 1, and FIG. 2B is a cross-sectional view taken along line AA in FIG. FIG. 3 is a plan view showing an example of dimensions of each part of the high-frequency substrate fixing jig 1.

  As shown in FIGS. 1 and 2 (a) and 2 (b), the high-frequency substrate fixing jig 1 includes a jig substrate 11 and a positioning member 12. In the present embodiment, the jig substrate 11 is formed in a rectangular shape, and the positioning member 12 is formed in an L shape with an internal angle being a right angle.

  The jig substrate 11 has a configuration in which a copper foil layer 22 is formed on a glass epoxy substrate 21. In the jig substrate 11, an electromagnetic wave input hole 23 and a suction hole 24 that are through holes are formed at positions corresponding to the lower surface (back surface) of the high-frequency substrate 2 disposed on the jig substrate 11. The position of the electromagnetic wave input hole 23 is a position facing the connection window 44 of the high-frequency substrate 2 disposed on the jig substrate 11. The inner diameter of the electromagnetic wave input hole 23 is set to be the same as the inner diameter of the waveguide 13.

  The positioning member 12 has a configuration in which a copper foil layer 32 is formed on a glass epoxy substrate 31. The positioning member 12 is fixed to the jig substrate 11 with screws 16.

  At the position of the electromagnetic wave input hole 23 on the back surface of the jig substrate 11, a waveguide 13 having a flange shape and a coaxial / waveguide converter 14 are provided, and at the position of the suction hole 24, for example, A rubber suction pad 15 is provided. The coaxial / waveguide converter 14 is provided at the end of the waveguide 13, for example. The waveguide 13 is attached to the jig substrate 11 with, for example, screws 16, and the suction pad 14 is attached to the jig substrate 11 with, for example, an adhesive.

  As described above, the reason why the waveguide 13 is used for the high-frequency substrate fixing jig 1 is to suppress transmission loss due to soldering or the like that occurs when a coaxial cable is used, particularly in millimeter waves, and reduce transmission loss. This is for lowering.

(Configuration of the high-frequency substrate 2)
4A is a plan view showing the upper surface (front surface) of the high-frequency substrate 2, FIG. 4B is a plan view showing the lower surface (back surface) of the high-frequency substrate 2, and FIG. 3 is a side view of the high-frequency substrate 2. FIG. In the present embodiment, the high-frequency substrate 2 is a waveguide feeding type antenna element.

  As shown in FIGS. 4A to 4C, the high-frequency substrate 2 has an antenna pattern 42 formed on the upper surface (front surface) of the quartz substrate 41 and a copper foil layer 43 formed on the back surface of the quartz substrate 41. It is a configuration. The high-frequency substrate 2 constitutes a microstrip array antenna that is a high-frequency antenna element, and is for millimeter waves in this embodiment.

  Further, as shown in FIG. 4B, a connection window 44 is formed on the lower surface (back surface) of the high-frequency substrate 2. The waveguide 13 is connected to the antenna pattern 42 of the high-frequency substrate 2 through the connection window 44.

(Configuration of characteristic measuring device 3)
Next, a characteristic measuring apparatus that measures the characteristics of the high-frequency substrate 2 will be described. FIG. 5 is a schematic diagram illustrating a configuration of a characteristic measuring apparatus 3 that includes the high-frequency substrate fixing jig 1 and measures the characteristics of the high-frequency substrate 2.

  As shown in FIG. 5, the characteristic measurement device 3 includes a network analyzer 51, a vacuum pump (suction device) 52, and a horn antenna 53.

  The network analyzer 51 is a vector network analyzer, for example, and outputs a high-frequency signal for measuring the characteristics of the high-frequency substrate 2. The network analyzer 51 includes an output terminal 51a and an input terminal 51b. The output terminal 51 a is connected to the coaxial / waveguide converter 14 provided at the end of the waveguide 13 of the high-frequency substrate fixing jig 1 by a coaxial cable 54. The vacuum pump 52 is connected to the suction pad 15 provided on the high-frequency substrate fixing jig 1 by an air pipe 55. The horn antenna 53 is disposed above the high-frequency substrate 2 disposed on the high-frequency substrate fixing jig 1. A waveguide 56 is connected to the horn antenna 53, and a coaxial / waveguide converter 57 is provided at the end of the waveguide 56. The coaxial / waveguide converter 57 is connected to the input terminal 51 b of the network analyzer 51 via the coaxial cable 58.

(Operation of the characteristic measuring device 3)
A method for measuring the characteristics of the high-frequency substrate 2 using the characteristic measuring apparatus 3 in the above configuration will be described.

  When measuring the characteristics of the high-frequency substrate 2 including the antenna pattern 42, the high-frequency substrate 2 is disposed on the high-frequency substrate fixing jig 1 in the characteristic measuring apparatus 3 shown in FIG. 5. In this case, the high-frequency board 2 is arranged such that the antenna pattern 42 is on the upper side and the short side on the connection window 44 side and one long side continuous with the short side are in contact with the positioning member 12. As a result, the high frequency substrate 2 is easily positioned at a predetermined measurement position (arrangement position) on the jig substrate 11. In a state where the high-frequency substrate 2 is positioned at the measurement position of the high-frequency substrate fixing jig 1, the position of the connection window 44 of the high-frequency substrate 2 and the position of the opening at the end of the waveguide 13 of the high-frequency substrate fixing jig 1 Match.

  Next, the vacuum pump 52 is operated. Thereby, the back surface of the high frequency substrate 2 is sucked by the vacuum pump 52 through the suction hole 24, the suction pad 15 and the air pipe 55 of the jig substrate 11, and the high frequency substrate 2 is fixed to the measurement position.

  In the above state, when a high frequency signal is output from the output terminal 51a of the network analyzer 51, the high frequency signal is input to the coaxial / waveguide converter 14 via the coaxial cable 54 and converted into electromagnetic waves. The This electromagnetic wave is input from the connection window 44 to the high-frequency substrate 2 through the waveguide 13 and the electromagnetic wave input hole 23 of the jig substrate 11. Thereby, electromagnetic waves are radiated from the antenna pattern 42 of the high-frequency substrate 2.

  The electromagnetic wave radiated from the high-frequency substrate 2 is received by the horn antenna 53, is input to the coaxial / waveguide converter 57 via the waveguide 56, and is converted into a high-frequency signal. This high frequency signal is input to the network analyzer 51 via the coaxial cable 58 and the input terminal 51 b of the characteristic measuring device 3, and the characteristic of the high frequency substrate 2 is measured by the network analyzer 51.

(Advantages of the high-frequency substrate fixing jig 1)
As described above, the configuration in which the high-frequency substrate 2 is fixed on the jig substrate 11 by the suction of the vacuum pump 52 is such that the load applied to the high-frequency substrate 2 by the suction of the vacuum pump 52 is deformed by the high-frequency substrate 2 or the high-frequency substrate 2. The quartz substrate 41 is not cracked and can be easily adjusted to an appropriate load capable of fixing the high-frequency substrate 2 to the jig substrate 11.

  Therefore, the load applied to the high-frequency substrate 2 is smaller than the configuration in which the high-frequency substrate 2 is fixed on the jig substrate 11 with screws or the configuration in which the high-frequency substrate 2 is pressed and fixed from above with a member that covers the high-frequency substrate 2 from above. Thus, the high-frequency substrate 2 can be fixed at the measurement position on the jig substrate 11. Furthermore, since the deformation of the high frequency substrate 2 is suppressed, the characteristics of the high frequency substrate 2 can be accurately measured.

  Furthermore, since there is no member that affects the radiation of electromagnetic waves of the high frequency substrate 2 on the high frequency substrate 2, the characteristics of the high frequency substrate 2 can be accurately measured.

  In addition, since the positioning member 12 is L-shaped, it can respond to the high-frequency board | substrate 2 of a different size.

(Comparative example)
FIG. 6 is a perspective view showing a high-frequency substrate fixing jig 61 according to a comparative example with respect to the high-frequency substrate fixing jig 1. 7 is a cross-sectional view taken along line BB in FIG.

  The high-frequency substrate fixing jig 61 is different from the high-frequency substrate fixing jig 1 in the positioning method of the high-frequency substrate 2 and the fixing method of the high-frequency substrate 2.

  Specifically, as shown in FIGS. 6 and 7, the high-frequency substrate fixing jig 61 includes an upper cover member 71 instead of the positioning member 12 and the suction pad 15 of the high-frequency substrate fixing jig 1. Therefore, the suction hole 24 is not formed in the jig substrate 11. Other configurations are the same as those of the high-frequency substrate fixing jig 1.

  Similar to the positioning member 12, the upper cover member 71 has a configuration in which a copper foil layer 82 is formed on a glass epoxy substrate 81 and an exposure window 83 is formed in the center. The exposure window 83 is for exposing the antenna pattern 42 of the high-frequency substrate 2. The upper cover member 71 is fixed to the jig substrate 11 with screws 16.

  The upper cover member 71 positions and fixes the high-frequency substrate 2 disposed on the jig substrate 11 in a state where the upper cover member 71 is screwed to the jig substrate 11. Therefore, the portion of the exposed window 83 of the upper cover member 71 includes a positioning portion 83a corresponding to the outer shape of the high-frequency substrate 2 and a pressing portion 83b that suppresses the periphery of the upper surface of the high-frequency substrate 2 positioned by the positioning portion 83a. It has a two-stage structure. That is, the upper cover member 71 positions the high frequency substrate 2 at a predetermined measurement position by the positioning portion 83a, and presses and fixes the high frequency substrate 2 to the jig substrate 11 by the pressing portion 83b.

  In the configuration in which the high frequency substrate 2 is pressed by the upper cover member 71 and fixed at the measurement position like the high frequency substrate fixing jig 61 described above, an excessive load is easily applied to the high frequency substrate 2, and the quartz substrate 41 of the high frequency substrate 2. Are susceptible to cracking and deformation. For this reason, there exists a possibility that the high frequency board | substrate 2 may be destroyed, or the high frequency board | substrate 2 may deform | transform and the characteristic of the high frequency board | substrate 2 cannot be measured correctly. Further, since a part of the upper cover member 71, that is, the pressing portion 83b exists on the periphery of the high-frequency substrate 2, the radiation characteristic of the high-frequency substrate 2 is easily changed.

(Comparison result)
In order to confirm the effectiveness of the high-frequency substrate fixing jig 1 of this embodiment (see FIG. 1), the characteristic measuring apparatus 3 shown in FIG. 5 is used to show the high-frequency substrate fixing jig 1 and FIG. The high frequency substrate fixing jig 61 was compared in terms of the influence on the high frequency characteristics of the antenna element.

  The antenna element to be measured is the high-frequency substrate 2 shown in FIG. 4, that is, the microstrip array antenna. The high-frequency substrate 2 has a quartz substrate 41 thickness of 0.5 mm and a copper foil layer 43 thickness of 35 μm, and is designed to operate in the 60 GHz band.

  The comparison results are shown in FIGS. FIG. 8 is a graph showing the reflection characteristics of the high-frequency substrate 2 when the high-frequency substrate fixing jig 1 (Example) is used and when the high-frequency substrate fixing jig 61 (Comparative Example) is used. FIG. 9 is a graph showing the radiation characteristics of the high-frequency substrate 2 when the high-frequency substrate fixing jig 1 (Example) is used and when the high-frequency substrate fixing jig 61 (Comparative Example) is used. In FIG. 9, S11 represents the amplitude of the reflection coefficient and serves as an index of the power supply ratio to the antenna.

  As can be seen from FIG. 8, the reflection characteristics are not so different between the high-frequency substrate fixing jig 1 (example) and the high-frequency substrate fixing jig 61 (comparative example). However, as can be seen from FIG. 9, the radiation characteristics when the high-frequency substrate fixing jig 61 (comparative example) is used are the radiation characteristics when the high-frequency substrate fixing jig 1 (example) is used. On the other hand, it has deteriorated significantly. Therefore, according to this comparison result, in the high-frequency substrate fixing jig 1 in which no member (upper cover member 71) is provided on the high-frequency substrate 2, some member (upper cover member 71) is provided on the high-frequency substrate 2. It was found that the influence on the antenna characteristics was smaller than that of the high-frequency substrate fixing jig 61, and the antenna characteristics could be measured accurately.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

  INDUSTRIAL APPLICABILITY The present invention can be used when measuring element characteristics by fixing a substrate-shaped element that includes a planar high-frequency antenna such as a millimeter wave band that is easily damaged by an external force.

DESCRIPTION OF SYMBOLS 1 High frequency board fixing jig 2 High frequency board 3 Characteristic measuring apparatus 11 Jig board 12 Positioning member 13 Waveguide 14 Coaxial / waveguide converter 15 Adsorption pad 21 Glass epoxy board 22 Copper foil layer 23 Electromagnetic wave input hole 24 Suction hole 31 Glass epoxy substrate 32 Copper foil layer 41 Quartz substrate 42 Antenna pattern 43 Copper foil layer 44 Connection window 51 Network analyzer 52 Vacuum pump (suction device)
53 Horn Antenna 54 Coaxial Cable 55 Air Pipe 56 Waveguide 57 Coaxial / Waveguide Converter

Claims (4)

In a high-frequency substrate fixing jig that fixes a high-frequency substrate whose characteristics are to be measured,
A jig substrate having a suction hole which is a through-hole, an upper end of the suction hole being opened at an arrangement position of the high-frequency substrate on an upper surface, and a lower end being opened on a lower surface;
A high-frequency substrate fixing jig, comprising: a suction pad provided at a lower end of the suction hole on the lower surface of the jig substrate, to which a suction device for sucking air is connected. The jig substrate has an electromagnetic wave input hole which is a through hole, and an upper end of the electromagnetic wave input hole is opened at a position facing an electromagnetic wave input portion of the high frequency substrate at a position where the high frequency substrate is disposed, and a lower end is Open on the bottom,
The high-frequency substrate fixing jig according to claim 1, wherein a waveguide to which the measurement device for the high-frequency substrate is connected is provided at a lower end position of the electromagnetic wave input hole on the lower surface of the jig substrate. Ingredients.   An L-shaped positioning member for positioning the high-frequency substrate is provided by contacting a first side of the high-frequency substrate and a second side adjacent to the first side. The high-frequency substrate fixing jig according to claim 1 or 2. In the method for measuring the characteristics of a high-frequency substrate in which the high-frequency substrate to be measured is fixed on a jig substrate and measured
The jig substrate has a suction hole which is a through-hole, and an upper end of the suction hole is opened at an arrangement position of the high-frequency substrate on an upper surface, and a lower end is opened on a lower surface,
A method for measuring characteristics of a high-frequency substrate, wherein air is sucked from a lower end of the suction hole on the lower surface of the jig substrate, the high-frequency substrate is fixed at the arrangement position, and the characteristics of the high-frequency substrate are measured.

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