JP2001044719A - Coupler with built-in low-pass filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coupler with a built-in low pass filter that produces a stable coupling value. SOLUTION: The coupler with a built-in low pass filter is formed by laminating insulation boards on which various conductor lines or electrodes are formed, and provided with an inductance main line 16 and a couple line 15. Since the inductance main line 16 or partial inductance lines 16L, 16R configuring the inductance main line 16 and the couple line 15 are formed at the same time on the same insulation board 14 at a prescribed intervals s1 opposed to each other, the lines 15, 16L, 16R are always formed in the same shape, there is no change in the interval and the coupling value is always made constant to make the characteristic stable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-pass filter built-in coupler having a built-in low-pass filter for cutting harmonics used in radio equipment.

[0002]

2. Description of the Related Art FIG. 7 shows a circuit configuration of a conventional portable telephone. Here, the duplexer 80 distributes the radio wave received via the antenna 82 to the receiving circuit 50 side, and transmits the high-frequency signal from the transmitting circuit 60 to the antenna 82 side. The transmission circuit 60 includes a mixer 62 that modulates a source signal at a high frequency from an oscillator 64, a bandpass filter 66 that cuts a high frequency component and a low frequency component in an output from the mixer 62, and amplifies an output of the bandpass filter 66. Power amplifier 68, an output of the power amplifier 68 to the low-pass filter 74 side, a coupler 72 for distributing a part of the output to the automatic gain adjustment line 70 side, and a power amplifier 68 based on the output transmitted from the coupler. An automatic gain adjustment line 70 that adjusts the gain to keep the radio output radiated from the antenna in a certain range, and a low-pass filter 7 that cuts harmonics (second and third harmonics) in the output from the coupler.
4 The low-pass filter 74 cuts the second and third harmonics generated by the power amplifier 68 having a non-linear amplification characteristic, and suppresses a spurious component in the wireless output.

On the other hand, a coupler 72 detects an output of a power amplifier 68. FIG. 8 shows an equivalent circuit of this coupler.
The coupler 72 has an input terminal (IN) for inputting a signal from the power amplifier side, an output terminal (OUT) for outputting to the low-pass filter 74 side, and a couple output terminal for outputting a detected output to the automatic gain adjustment line 70 side. (COUPLED
OUT) and a termination terminal E connected to a termination resistor R of 50Ω, and an input terminal (IN) and an output terminal (OUT).
Is connected to the first couple line 72a,
The couple output terminal (COUPLED OUT) and the ground terminal (E) are connected to the second couple couple line 72.
b. This first couple line 72a
And the second couple couple line 72b are electromagnetically coupled. Here, in the coupler 72, it is necessary to reduce the current flowing to the terminating resistor R side, that is, to increase the isolation from the viewpoint of suppressing the power consumption of the entire mobile phone. Here, when the first couple line 72a is formed to have a length of 入 of the signal input, the isolation can be maintained at a high value.
The 入 of the obi is 8 to 4 cm, and with a small coupler,
It is impossible to realize the first couple line 72a of the input / 4 wavelength. For this reason, various proposals have been made to enhance isolation while using short couple lines.

[0004]

In a conventional radio (cellular phone), a low-pass filter 74 and a coupler 7 are used.
Since the components 2 are composed of separate members, manufacturing and assembling costs are increased, and this also prevents the wireless device from being downsized. Further, a low-pass filter 74 and a coupler 72
Transmission loss between the wireless communication device and the power consumption of the wireless device is increased.

In view of the above, an insulating substrate having various conductive lines formed thereon is laminated to provide an inductance main line for transmitting a high-frequency signal, a couple line line electromagnetically coupled to the inductance main line, and a capacitor. The applicant has already proposed a low-pass filter built-in coupler including a low-pass filter composed of an inductor and an inductor of an inductance main line.

In order to realize this configuration, there has been proposed a configuration in which various conductive lines or electrodes are formed for each insulating substrate, and these are stacked. In this method, an inductance main line and a couple line line that are mutually coupled are formed on different insulating substrates.

For this reason, each of them is separately formed on the insulating substrate by screen printing. However, although the process is controlled so as to be formed at the same position as much as possible, each of them is controlled by the positional accuracy of the screen printing machine. Unevenness in the vertical and horizontal directions between the inductance main line and the couple line line may occur due to printing variations between the insulating substrates and thickness errors of the insulating substrate. I couldn't get it. For this reason, the characteristics of the coupler with a built-in low-pass filter vary. An object of the present invention is to solve such a problem.

[0008]

According to the present invention, there is provided an inductance main line for transmitting a high-frequency signal by laminating an insulating substrate on which various conductive lines or electrodes are formed, and an electromagnetic coupling between the inductance main line and the inductance main line. A low-pass filter with a built-in low-pass filter including a coupled line line and a capacitor and an inductor of an inductance main line, wherein: a partial inductance line forming the inductance main line or a part thereof; Are formed at the same time on the same insulating substrate at a predetermined interval so as to face each other.

In such a configuration, since the inductance main line or the partial inductance line and the couple line line are formed simultaneously on the same insulating substrate by screen printing or the like, the inductance main line or the partial inductance line and the couple inductance line are coupled together. The line lines are always formed in the same form, and there is no change in the mutual distance. Therefore, the coupling value is stabilized.

In order to form an inductance main line having a predetermined inductance value while maintaining the miniaturization of the coupler, the inductance main line is formed by forming a plurality of partial inductance lines on different insulating substrates. It is necessary to connect and connect these in a stacked state. One of the partial inductance lines is formed on the same insulating substrate at a predetermined distance from the couple line lines so as to face each other, but the other partial inductance line has a different insulation from the couple line lines. Since it is formed on the substrate, the position of the other partial inductance line and the position of the couple line line vary, and as a result,
Variations in the overall coupling value occur.

Therefore, there is proposed a configuration in which the other partial inductance line is provided at a distance from the couple line line more than the one partial inductance line. In such a configuration, the coupling value generated between the other partial inductance line and the couple line line becomes as small as possible, and the influence of the position variation is suppressed.

Further, in the inside of the laminated layer of the coupler,
The capacitance electrode is opposed to the coupled line via the insulating substrate. As the facing area increases, the coupling capacitance increases, and the isolation of the coupler tends to deteriorate. Therefore, a decrease in the isolation is prevented by reducing the facing area.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A coupler with a built-in low-pass filter according to a first embodiment of the present invention will be described. FIG. 6 shows a configuration of a mobile phone using the coupler with a built-in low-pass filter of the present invention. This mobile phone uses a 1 GHz band and includes a receiving circuit 50, a transmitting circuit 60, and a duplexer 80 connected to an antenna 82. The duplexer 80 distributes radio waves received via the antenna 82 to the receiving circuit 50 side, and transmits a high-frequency signal from the transmitting circuit 60 to the antenna 82 side.

The transmitting circuit 60 includes a mixer 62 for modulating a source signal from an oscillator 64 to a high frequency, and a band for filtering an output from the mixer 62 to cut a high frequency component above a predetermined threshold and a low frequency component below a predetermined threshold. Pass filter 66
A power amplifier 68 for amplifying the output of the band-pass filter 66, a harmonic (second and third harmonic) in the output of the power amplifier 68, and sending the cut harmonic to the duplexer 80 side. The gain of the power amplifier 68 is adjusted based on the output from the coupler 10 with a built-in low-pass filter and the output from the coupler 10 with a built-in low-pass filter to maintain the wireless output radiated from the antenna within a certain range. And an automatic gain adjustment circuit 70.

The low-pass filter built-in coupler 10 cuts the second and third harmonics generated by the power amplifier 68 having a non-linear amplification characteristic, and suppresses spurious components in the radio output. It also has the function of a detection coupler for detecting the output of the amplifier 68.

FIG. 5A shows the appearance of the coupler 10 with a built-in low-pass filter. FIG. 1 shows the insulating layers of the low-pass filter built-in coupler 10 separately. Here, as shown in FIG. 5 (A), the coupler 10 with a built-in low-pass filter has a rectangular parallelepiped shape, a width of 3.2 mm and a depth of l.
6 mm, height l. It is formed to 3 mm. Conducting recesses 10a, 10a, 10b having conductive layers 11 formed in recesses vertically penetrating on both side surfaces of the low-pass filter built-in coupler.
b, 10c, 10d, 10e, and 10f are provided. On the bottom surface of the low-pass filter built-in coupler 10, an electrode pad for mounting the low-pass filter built-in coupler 10 on a substrate (not shown) is formed, and the electrode pad is connected to the conductive concave portion. By mounting the built-in coupler 10 on a substrate (not shown),
Each conductive recess is connected to a required external electric path on the substrate. In FIG. 1, the conductive recesses 10a, 10b, 10c, 10d, 1 on the sides of the low-pass filter built-in coupler are shown.
The conductive layers filled in 0e and 10f are omitted for convenience of illustration.

As shown in FIG. 1, a low-pass filter built-in coupler 10 includes insulating substrates 12, 14, 17, 18, 20, and 20.
24, 26, and 31 are laminated and have the above-described rectangular parallelepiped shape. Here, the insulating substrate 12 is an external plate that protects an internal circuit. The insulating substrate 14 forms a main part of the present invention, and has meandering partial inductance lines 16L and 16R formed on the left and right sides, and vertical line segments 16a and 16a formed along the long sides of the plate. A couple line 15 also formed along the long side is formed at a predetermined interval. Outer edges of the partial inductance lines 16L and 16R are connection edges facing the conductive recesses 10d and 10f. In addition, couple line track 15
Also face the conductive recesses 10a and 10c.

[0018] The couple line line 15 and the partial inductance line 16L, and 16R are formed simultaneously by screen printing, and therefore, the interval _{s 1} between the vertical line segment 16a, 16a and couples the line line 15 is always constant.

On the upper surface of the insulating substrate 17, a partial inductance line 16C is formed. Both ends of the partial inductance line 16C are connected to the inner edges of the left and right partial inductance lines 16L, 16R via via holes 35, 35 formed in the insulating substrate 14. As a result, the partial inductance lines 16L, 16C, and 16R are line-connected, and the inductor L
_1, the inductance main line 16, _{L 2} is to be configured.

A capacitance electrode 19 is formed on the upper surface of the insulating substrate 18 in a rectangular shape.

On the upper surface of the insulating substrate 20, capacitance electrodes 21L and 21R are formed on the left and right. The edges of the capacitance electrodes 21L and 21R extend to the side edges of the insulating substrate 20. An intermediate electrode 22a is formed at the center.

A ground electrode 25 is formed on the upper surface of the insulating substrate 24. Further, an intermediate electrode 22b is formed at the center thereof so as to be insulated from the ground electrode 25.

On the upper surface of the insulating substrate 26, capacitance electrodes 29L and 29R are formed on the left and right. The capacitance electrodes 29L and 29R have their edges extending to the side edges of the insulating substrate 28, and are exposed to the outside from the conductive recesses 10d and 10f. In the center thereof, a capacitance electrode 30 is provided.
Are formed.

An earth electrode 32 is formed on the upper surface of an insulating substrate 31 which is a bottom plate.

Via holes 36a to 36d are formed in the center of the insulating substrates 17, 18, 20, and 24, and the partial inductance line 16C, the capacitance electrode 19, and the intermediate electrode 22 are formed through the via holes 36a to 36d.
a, the intermediate electrode 22b, and the capacitance electrode 30 are connected to each other.

On the side surface of the low-pass filter built-in coupler 10, the edges of the partial inductance line 16L, the capacitance electrode 21L and the capacitance electrode 29L are connected to each other by a conductive layer filled in the conductive recess 10d. Electrode 2
1R and the edge of the capacitance electrode 29R are connected to each other by a conductive layer filling the conductive recess 10f. Further, external input / output electric paths are connected to the conductive concave portions 10d and 10f. The edge of the couple line 15 is also a conductive recess 1.
External electric circuits are connected via 0a and 10c. The ground electrodes 25 and 32 are connected to each other by a conductive layer filled in the conductive recess 10e. Further, the conductive recess 10e
Is connected to an external ground line.

FIG. 4 is an equivalent circuit diagram of this embodiment.
In this equivalent circuit diagram, the inductance main line 16
Is connected to one end of the inductance main line 16 and the capacitance electrode 21L connected to one end of the inductance main line 16 is connected to the ground electrode 25.
Forming a capacitor C ₁ by between the capacitance and opposed with 5, 32. Similarly, the capacitance electrode 21R connected to the other end of the inductance main line 16 is opposed to the ground electrode 25, and
Capacitance electrodes 29R to one end of the connection forms a capacitor _{C 2} and opposed to the earth electrodes 25 and 32. The capacitance electrode 19 is connected to the middle of the inductors L ₁ and L ₂ via the via hole 36, and the capacitance electrode 19 is opposed to the capacitance electrodes 21 L and 21 R, and the capacitors C ₃ and C ₃ are connected to each other.
₄ are formed. Further, the intermediate electrodes 22a, 22b
The capacitance electrode 30 connected between the inductors L ₁ and L ₂ through the capacitor C ₅ constitutes a capacitor C ₅ opposite to the ground electrode 32.

Thus, the equivalent circuit of FIG. 4 is formed. Each conductive path and each electrode are formed by performing screen printing on each insulating plate.

Here, as described above, the inductance main line 16 is composed of the partial inductance lines 16L, 16C,
16R are connected by wire, and the two insulating substrates 14 and 1
7, the low-pass filter built-in coupler 1 can maintain the required wire length of the inductance main line 16.
0 can be reduced in plane area.

Then, as shown in FIG. 2A, the insulating substrate 1
Since 4 couples line line 15 and the partial inductance line 16L, the inductance main line 16R are simultaneously formed by screen printing, as described above, the interval s ₁ can be maintained constant, the variation of the coupling values blocking As a result, a low-pass filter built-in coupler 10 having stable characteristics can be provided.

Incidentally, the partial inductance line 16C constituting the inductance main line 16 as described above is used.
Is the insulating substrate 14 on which the couple line line 15 is formed
Is formed on an insulating substrate 17 different from the above. For this reason, due to the accuracy error of the screen printing machine and the thickness error of the insulating substrate 14, as shown in FIG.
5 and cause variation in the spacing s ₂ between inductance main line 16C, can not be prevented completely the variation of coupling value by a change in the degree of coupling couples line line 15 and the partial inductance line 16C.

In the first embodiment, the inductance main line 16 may be formed on a single insulating substrate. In this case, the inductance main line 16 is separated from the couple line line 15 by a predetermined distance s. _{1 and} are simultaneously formed by screen printing.

Therefore, in the second embodiment, FIG.
As shown in (B), the position of the partial inductance line 16C is deviated from the partial inductance lines 16L and 16R in the direction away from the couple line line 15 using the insulating substrate 17 'instead of the insulating substrate 17. It is position, thereby lengthening the interval s ₂ between the couple line line 15 and the inductance main line 16C, couples line line 1
The degree of coupling between the wire 5 and the partial inductance line 16C is reduced, and the influence of the variation on the characteristics is prevented as much as possible. FIG. 3A is the same as FIG. 2A, and the second embodiment is the same as the first embodiment except that an insulating substrate 17 'is used. Omitted.

In each of the above embodiments, the insulating substrate 14 having the partial inductance lines 16L and 16R, the couple line line 15 formed on the upper surface, the insulating substrate having the partial inductance line 16C formed thereon, and the partial inductance line 16C are formed. As shown in FIG. 9, a cross section of a partially laminated portion of the formed insulating substrate 17 and the capacitance electrode 18 on which the capacitance electrode 19 is formed, the couple line 15 is connected to the capacitance electrode 19 via the insulating substrates 14 and 17. A required coupling capacity is formed between the two. This coupling capacitance is determined by the facing area F when the dielectric constant of the substrate and the length and width of the couple line 15 are kept constant. However, the present inventor has found that the smaller the facing area S, the better the isolation of the coupler. Was confirmed by experiments.

Therefore, as a third embodiment of the present invention, the width dimension of the couple line 15 is reduced (d ₂ ),
The capacitance electrode 19 was reduced (d ₁ ) to reduce the facing area F between them.

Here, the outer edge of the capacitance electrode 19 is set to be d ₁ = 5 more than the outer edge of the couple line 15.
FIG. 10 (d ₁ = 50 μm, d ₂ =
0), and FIG. 11 (d ₁ = 100 μm, d ₂ = 0). Also, d ₁ = 100 μm, and the width of the couple line 15 is set to 150 μm to 100 μm (d ₂
= 50 μm) is shown in FIG.

For comparison, FIG. 13 shows the attenuation characteristics when d ₁ and d ₂ are zero, that is, when the outer edge of the couple line 15 is 150 μm in width and the outer edge of the capacitance electrode 19 is matched.

FIGS. 10 to 1 according to a third embodiment of the present invention.
2, the isolation at 1.785 GHz was −27.3 dB (d ₁ = 50 μm, d ₂ =
0), -29.7 dB (d ₁ = 100 μm, d ₂ =
0), -34.9 dB (d ₁ = 100 μm, d ₂ = 5
0 μm), which is −27.2 dB of the comparative example shown in FIG.
It was recognized that the improvement was remarkable as compared with.

FIGS. 10 to 13 are graphs showing the results of simulating the attenuation characteristic of the coupler 10 with a built-in low-pass filter.

The vertical axis of the graph in the figure indicates the attenuation value (dB), with the uppermost part being 0 dB, the lowermost part being -50 dB, and one division being -5 dB. On the other hand, the horizontal axis indicates the frequency, with the left end (lowest frequency) being 0.5 GHz, the right end (highest frequency) being 6 GHz, and the 1 division being 0.55 GHz.

The upper graph in each figure shows the characteristics of the low-pass filter built-in coupler as a low-pass filter. Curve indicated by S _2, the characteristic is inputted from the input port P ₁ to the output port P _2, that is, the high frequency attenuation characteristics of the low-pass filter. Meanwhile, the curve indicated by S ₁ returns characteristics input from the input port P ₁ input port P _1, that is, the reflection characteristic of the low-pass filter.

The lower graph in each figure shows the characteristics of the coupler with a built-in low-pass filter as a coupler. S ₃
Curve indicated by the input from the input port P ₁ is outputted from the detection port P _3, that is, the detection output outputted from the low-pass filter built coupler 10 shown in FIG. 6 to the automatic gain control circuit 70. Meanwhile, the curve indicated by S ₄ shows the isolation output is input from the terminal port P ₄ from the input port P _1. Such isolation values are as described above.

Built-in low-pass filter of each embodiment
As shown in the equivalent circuit of FIG.
L₁ And capacitor C₁ , C₃ Input connected to
Power port P₁ And the inductor L₂ And capacitor C₄
 , C₆ Output port P connected to₂ And a couple
Connected to line line 15, automatic gain adjustment of part of output
Detection port P for output to circuit 70₃ And the bracket
50Ω (ohm) connected to the pull line insulating substrate 15
Termination port P connected to termination resistor (not shown)₄ When
Is provided. Input port P₁ Is the low pass filter shown in FIG.
In the coupler 10 with a built-in filter, the inductor L₁ as well as
Capacitor C₁ , C₃ To the conductive recess 10d connected to
Correspondingly, output port P₂ Is the inductor L₂ 
And capacitor C₄ , C₆ Conduction recess 10 connected to
corresponds to f. In addition, detection port P ₃ The couple
Corresponds to conductive recess 10a connected to one end of in-line 15
Similarly, the termination port P₄ The couple line railroad
15 corresponds to the conductive recess 10c connected to the other end of the reference numeral 15. What
Note that the recesses 10b and 10e are
It is connected to the ground on the substrate side on which the plastic 10 is mounted.

Next, a method for manufacturing such a low-pass filter built-in coupler will be described with reference to FIG. FIG.
FIG. 2B is a plan view of a ceramic green sheet in which a large number (nine) of the lowermost insulating substrates 31 shown in FIG. 1 are taken. On the upper surface of the green sheet 40, a line pattern 42 for forming the ground electrode 32 shown in FIG. 2 is formed by screen printing. In the figure, the dotted lines indicate cutting lines when forming each insulating substrate, and along the dotted lines, the conductive recesses 10a, 10a,
Through holes 44 for forming b, 10c, 10d, 10e, and 10f are punched out by a punch. Similarly, a green sheet corresponding to each insulating substrate shown in FIG. 1 is formed, and these are laminated, and a silver paste is printed on the inner wall surface of the through hole 44 by a screen printing method. (B)
Cut along the dotted line inside. Thereafter, the green sheet forming the insulating substrate and the silver paste forming the line are simultaneously fired, whereby the low-pass filter built-in coupler 10 shown in FIG. 5A is completed.

The coupler 10 with a built-in low-pass filter according to the present embodiment is formed by laminating and integrating a plurality of insulating substrates on which conductive lines and electrodes are formed, and coupling the couple line line 15 and the inductance main line 16 to the low-pass filter. It has a built-in coupler. For this reason, the low-pass filter and the coupler can be formed inexpensively and compactly as compared with the case where the low-pass filter and the coupler are formed as separate components. Further, the transmission loss between the low-pass filter and the coupler can be reduced, and the power consumption of the wireless device can be reduced.

In particular, in the gist of the present invention, the partial inductance lines 16L and 16R of the low-pass filter
It is so arranged simultaneously formed by screen printing a couple line line 15 on the same insulating substrate 14, the interval s ₁ is always constant, can prevent the variation of the coupling values. Furthermore In the second embodiment, partial inductance line 16C a partial inductance line 16L which is formed on an insulating substrate, is retracted than 16R, and so a large spacing s ₂ between the couple line line 15 from and relative position error by screen printing of the insulating substrate 14 and 17 each other, small influence on the degree of coupling even if the variation in the spacing s ₂ by the thickness unevenness, it is possible to achieve a stable coupling value .

In this embodiment, the example in which the coupler with a built-in low-pass filter of the present invention is applied to a mobile phone has been described. However, the coupler with a built-in low-pass filter of the present invention can be used not only for a mobile phone but also for various wireless devices. Needless to say.

[0048]

According to the present invention, there is provided a low pass filter built-in coupler having an inductance main line and a couple line line, which is formed by laminating insulating substrates having various conductive lines or electrodes formed thereon. Since the partial inductance line and the couple line line that constitute the portion are formed simultaneously on the same insulating substrate at a predetermined interval so as to face each other, these lines are always formed in the same form, and the mutual interval changes. Therefore, the coupling value is always constant, and the characteristics are stabilized.

Further, a partial inductance line formed on an insulating substrate different from the couple line line is disposed at a distance from the couple line line more than a partial inductance line formed on the same insulating substrate as the line. In such a configuration, the coupling value generated between the other partial inductance line and the couple line line becomes as small as possible, and the relative error of the screen printing between the two insulating substrates and the thickness of the insulating substrate. Influences due to variations in positions caused by unevenness and the like are suppressed as much as possible, and the characteristics are further stabilized.

Further, inside the laminated layer of the coupler,
In a configuration in which the facing area between the couple line line and the capacitance electrode is reduced, it is possible to prevent a decrease in isolation.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing each insulating substrate constituting a low-pass filter built-in coupler according to a first embodiment of the present invention.

FIGS. 2A and 2B show insulating substrates 14 and 17 of the coupler with a built-in low-pass filter according to the first embodiment, wherein A is a plan view of the insulating substrate 14 and B is a plan view of the insulating substrate 17;

FIGS. 3A and 3B show insulating substrates 14 and 17 ′ of the coupler with a built-in low-pass filter according to the second embodiment, where A is a plan view of the insulating substrate 14 and B is a plan view of the insulating substrate 17 ′.

FIG. 4 is an equivalent circuit diagram of the coupler with a built-in low-pass filter according to the embodiment of the present invention.

FIG. 5A is a perspective view illustrating an appearance of a coupler with a built-in low-pass filter according to the embodiment, and FIG.
It is a top view of the green sheet which comprises the coupler with a built-in low-pass filter.

FIG. 6 is a block diagram showing a circuit configuration of a mobile phone using the low-pass filter built-in coupler according to the present invention.

FIG. 7 is a block diagram showing a circuit configuration of a mobile phone according to the related art using a low-pass filter and a coupler.

FIG. 8 is an equivalent circuit diagram of the coupler shown in FIG. 7;

FIG. 9 is a vertical sectional side view of a main part of the coupler with a built-in low-pass filter.

FIG. 10 is a waveform diagram showing characteristics of a low-pass filter built-in coupler when d ₁ = 50 μm and d ₂ = 0;
The upper side shows the characteristics as a low-pass filter, and the lower side shows the characteristics as a coupler.

FIG. 11 is a waveform diagram showing characteristics of a low-pass filter built-in coupler when d ₁ = 100 μm and d ₂ = 0, wherein the upper side shows the characteristics as a low-pass filter, and the lower side shows the characteristics as a coupler.

FIG. 12 is a waveform diagram showing characteristics of a low-pass filter built-in coupler when d ₁ = 100 μm and d ₂ = 50 μm, wherein the upper side shows characteristics as a low-pass filter;
The lower side shows the characteristics as a coupler.

FIG. 13 is a waveform diagram showing characteristics of a low-pass filter built-in coupler when d ₁ and d ₂ = 0, wherein the upper side shows the characteristics as a low-pass filter and the lower side shows the characteristics as a coupler.

[Explanation of symbols]

 10 Coupler with built-in low-pass filter 14, 17, 18, 20, 24, 26, 31 Insulating substrate 15 Coupled line line 16 Inductance main line 16L, 16R, 16C Partial inductance line

[Procedure amendment]

[Submission date] August 3, 1999 (1999.8.3)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0038

[Correction method] Change

[Correction contents]

FIGS. 10 to 1 according to a third embodiment of the present invention.
2, the isolation at 1.785 GHz was −27.3 dB (d ₁ = 50 μm, d ₂ =
0), -29.7 dB (d ₁ = 100 μm, d ₂ =
0), -34.9 dB (d ₁ = 100 μm, d ₂ = 5
0 μm), which is −25.9 dB in the comparative example shown in FIG.
It was recognized that the improvement was remarkable as compared with.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Tatsuya Takemura 14-18 Takatsuji-cho, Mizuho-ku, Nagoya F-Term in Japan Special Ceramics Co., Ltd. 5J024 AA01 BA11 BA19 CA03 CA09 CA11 DA04 DA29 DA35 EA01 FA00 FA03 KA01

Claims (3)

[Claims] An insulated substrate having various conductive lines or electrodes formed thereon is laminated, and includes an inductance main line for transmitting a high-frequency signal, and a couple line line electromagnetically coupled to the inductance main line. Further, in a low-pass filter built-in coupler including a low-pass filter including a capacitor and an inductor of an inductance main line, the inductance main line or a partial inductance line forming the portion thereof and a couple line line are specified on the same insulating substrate. A coupler with a built-in low-pass filter, which is simultaneously formed in an opposed shape at intervals. 2. An inductance main line is constructed by connecting a plurality of partial inductance lines formed on different insulating substrates, respectively, and one of the partial inductance lines is formed on the same insulating substrate. Claims: A pair of a partial inductance line (B) is formed to be opposed to a couple line line at a predetermined distance, and the other partial inductance line (B) is arranged more apart from the couple line line than one partial inductance line (A). Item 6. A coupler with a built-in low-pass filter according to Item 1. 3. The coupler with a built-in low-pass filter according to claim 1, wherein a facing area between the coupled line and a capacitance electrode facing the coupled line via an insulating substrate is reduced.