JP6692569B2 - High frequency circuit module and high frequency circuit board - Google Patents

Description

  The present invention relates to a high frequency circuit module having a transmission line that transmits a high frequency signal, and a high frequency circuit board including a plurality of high frequency circuit modules.

  A high-frequency circuit module having a transmission line that transmits a high-frequency signal is equipped with various filter circuits such as a low-pass filter, a high-pass filter, a band-pass filter, and a band elimination filter in order to select a desired frequency band.

  These filter circuits can be constructed by combining passive elements such as inductors, capacitors and resistors. An example of the filter circuit is the LC filter circuit described in Patent Document 1, for example. The LC filter circuit is a filter circuit that combines an inductor and a capacitor, and the RC filter circuit is a filter circuit that combines a resistor and a capacitor.

  These conventional filter circuits include at least two passive elements. At least one of the passive elements is inserted in series with the signal line, and the remaining passive elements are arranged so as to connect the signal line and the ground in parallel.

JP 2009-124072 A (Published June 4, 2009)

  In the conventional filter circuit configured as described above, the passive element and the ground line connected in parallel are arranged in one of the two regions separated by the signal line (see Patent Document 1). Therefore, the conventional filter circuit is represented by a circuit diagram which is asymmetric with respect to the signal line.

  Further, when the filter circuit is actually mounted on the transmission line substrate, the filter circuit is arranged asymmetrically with respect to the signal line. For example, when a filter circuit is mounted on a coplanar line that is widely used as a transmission line that transmits a high-frequency signal, a passive element connected in parallel to the signal line is one of a pair of ground patterns that sandwich the signal line. Only connected to the ground pattern. Therefore, even in the structure in the real space, the conventional filter circuit has an asymmetric structure with respect to the signal line.

  In such a structure that is asymmetric with respect to the signal line, the current of the high-frequency signal that is removed by the filter circuit flows only in the ground pattern to which the passive element is connected. Therefore, a potential difference is generated between the pair of ground patterns that sandwich the signal line. This potential difference causes an electric field in a region near the signal line, which causes noise to be superimposed on the high frequency signal transmitted by the signal line.

  The present invention has been made in view of the above problems, and an object thereof is to suppress noise superimposed on a high frequency signal in a high frequency circuit module having a transmission line that transmits the high frequency signal.

  In order to solve the above problems, a high frequency circuit module according to the present invention includes a dielectric substrate, a transmission line formed on the surface of the dielectric substrate, and first and second grounds formed on the surface. A pattern, first and second ground patterns sandwiching the transmission line, a passive element inserted in series with the transmission line, and a parallel connection between the transmission line and the first ground pattern One passive element, and a second passive element that connects the transmission line and the second ground pattern in parallel, the transmission line, the first ground pattern, the passive element, and the first The first circuit configured by the passive element is equivalent to the second circuit configured by the transmission line, the second ground pattern, the passive element, and the second passive element. It is characterized in.

  According to the above configuration, the first circuit and the second circuit are equivalent. Therefore, the symmetry between the distribution of the current flowing from the transmission line to the first ground pattern and the distribution of the current flowing from the transmission line to the second ground pattern can be enhanced, and the symmetry of the voltage drop can be enhanced. .. Therefore, the symmetry of the electric field formed in the vicinity of the transmission line, the first ground pattern, and the second ground pattern along with the transmission of the high frequency signal is enhanced, and as a result, the noise superimposed on the high frequency signal is suppressed. can do.

  In the high-frequency circuit module according to one aspect of the present invention, it is preferable that the component constant of the first passive element and the component constant of the second passive element are equal to each other.

  According to the above configuration, compared with the case where the component constants of the first passive element and the second passive element are different, the distribution of the current flowing from the transmission line to the first ground pattern and the transmission line The symmetry with the distribution of the current flowing through the second ground pattern can be further enhanced, and the symmetry of the voltage drop can be enhanced. As a result, noise superimposed on the high frequency signal can be further suppressed.

  In the high-frequency circuit module according to one aspect of the present invention, the first ground pattern and the second ground pattern are arranged line-symmetrically with respect to the transmission line when the dielectric substrate is viewed in a plan view. It is preferable that the first passive element and the second passive element are arranged in line symmetry with respect to the transmission line when the dielectric substrate is viewed in a plan view.

  According to the above configuration, the first ground pattern and the second ground pattern are arranged line-symmetrically with respect to the transmission line, and the first passive element and the second passive element are with respect to the transmission line. Are arranged in line symmetry. Therefore, the symmetry between the distribution of the current flowing from the transmission line to the first ground pattern and the distribution of the current flowing from the transmission line to the second ground pattern is further increased, and the symmetry of the voltage drop is further increased. The effect of suppressing the potential difference generated between the ground pattern and the second ground pattern is improved. As a result, noise superimposed on the high frequency signal can be further suppressed.

  In the high frequency circuit module according to one aspect of the present invention, it is preferable that the shape of the first ground pattern and the shape of the second ground pattern are equal to each other.

  According to the above configuration, as compared with the case where the shape of the first ground pattern and the shape of the second ground pattern are different from each other, the distribution of the current flowing from the transmission line to the first ground pattern and the The symmetry with respect to the distribution of the current flowing in the second ground pattern can be further enhanced, and the symmetry of the voltage drop can be enhanced, and the transmission line and the first ground pattern can be transmitted along with the transmission of the high frequency signal. , And the symmetry of the electric field formed in the vicinity of the second ground pattern can be further enhanced. As a result, the noise superimposed on the high frequency signal can be further suppressed.

  A high frequency circuit module according to an aspect of the present invention is a ground pattern facing the transmission line, the back surface side ground pattern formed on the back surface of the dielectric substrate, the first ground pattern and the second ground pattern. It is preferable to further include a short circuit path group that short-circuits each of the ground patterns of 1) and the back side ground pattern.

  According to the above configuration, the first ground pattern and the second ground pattern are short-circuited via the short circuit path group and the back surface side ground pattern. Therefore, the potential difference generated between the first ground pattern and the second ground pattern can be further suppressed.

  In the high-frequency circuit module according to one aspect of the present invention, it is preferable that the short circuit path group is arranged line-symmetrically with respect to the transmission line when the dielectric substrate is viewed in a plan view.

  According to the above configuration, when the dielectric substrate is viewed in a plan view, the short circuit path group is not provided in a position line-symmetrical to the transmission line. It is possible to further improve the symmetry of the distribution of the current flowing through the device and to enhance the symmetry of the voltage drop.

  In the high-frequency circuit module according to one aspect of the present invention, when the effective wavelength of the high-frequency signal transmitted by the transmission line is set to λe and the dielectric substrate is viewed in plan, the first passive element and the second passive element are provided. It is preferable that the element and the short circuit path group are arranged within a circle having a radius of 0.1 × λe.

  With the above structure, the ground of the high-frequency circuit module according to one embodiment of the present invention can be regarded as a single-point ground. Accordingly, the transmission line formed by the transmission line provided in the high-frequency circuit module and each ground pattern functions as a better transmission line.

  In the high-frequency circuit module according to one aspect of the present invention, it is preferable that the shape of the first passive element and the shape of the second passive element are equal to each other.

  According to the above configuration, since the shapes of the first passive element and the second passive element are equal to each other, the distribution of the current flowing from the transmission line to the first ground pattern and the transmission line to the second ground pattern. The symmetry of the distribution of the current flowing in the pattern can be enhanced, the symmetry of the voltage drop can be enhanced, and the symmetry of the electric field formed near the transmission line and each ground pattern along with the transmission of the high frequency signal is further enhanced. be able to. As a result, noise superimposed on the high frequency signal can be further suppressed.

  In the high-frequency circuit module according to one aspect of the present invention, the passive element is an inductor or a capacitor, and each of the first passive element and the second passive element is, when the passive element is an inductor, When the passive element is a capacitor, the passive element is an inductor, and the first passive element and the second passive element are connected to at least one of an input side and an output side of the passive element. Is preferred.

  According to the above configuration, when the inductor is used as the passive element and the capacitor is used as each of the first passive element and the second passive element, the high-frequency circuit module according to one aspect of the present invention is a low-pass filter. Functions as a filter (LPF). On the other hand, when a capacitor is used as the passive element and an inductor is used as each of the first passive element and the second passive element, the high-frequency circuit module according to one aspect of the present invention functions as a high-pass filter (HPF). Function. Thus, the present invention can be applied to LPF or HPF.

  In the high frequency circuit module according to an aspect of the present invention, it is preferable that the first passive element and the second passive element are arranged on an input side and an output side of the passive element.

  The above configuration is applicable to a π-type LPF or HPF.

  In the high frequency circuit module according to an aspect of the present invention, the passive element includes an inductor and a capacitor connected in series or in parallel, and each of the first passive element and the second passive element is the passive element. When the element is composed of an inductor and a capacitor connected in series, it is composed of an inductor and a capacitor connected in parallel, and when the passive element is composed of an inductor and a capacitor connected in parallel, it is connected in series. It is preferable that the first passive element and the second passive element are connected to at least one of an input side and an output side of the passive element.

  According to the above configuration, when the inductor and the capacitor connected in series are adopted as the passive elements, and the inductor and the capacitor connected in parallel are adopted as each of the first passive element and the second passive element. In addition, the high-frequency circuit module according to one embodiment of the present invention functions as a bandpass filter (BPF). On the other hand, when the inductor and the capacitor connected in parallel are used as the passive elements and the inductor and the capacitor connected in series are used as the first passive element and the second passive element, the The high frequency circuit module according to the aspect functions as a band elimination filter (BEF). As described above, the present invention can be applied to BPF or BEF.

  In the high frequency circuit module according to an aspect of the present invention, it is preferable that the first passive element and the second passive element are arranged on an input side and an output side of the passive element.

  According to the above configuration, the present invention can be applied to a π type BPF or BEF.

  In the high frequency circuit module according to an aspect of the present invention, the passive element includes two inductors or capacitors connected in series, and each of the first passive element and the second passive element is the passive element. Are two inductors connected in series, a capacitor is used, and when the passive element is two capacitors connected in series, an inductor is used, the first passive element and the second passive element are used. The passive element is preferably located at the midpoint between the two inductors or capacitors.

  According to the above configuration, when two inductors connected in series are used as passive elements and capacitors are used as each of the first passive element and the second passive element, the present invention is It is applicable to LPF. On the other hand, when two capacitors connected in series are used as passive elements and an inductor is used as each of the first passive element and the second passive element, the present invention can be applied to the T-type HPF. is there.

  A high-frequency circuit module according to an aspect of the present invention is a dielectric substrate, a transmission line formed on the front surface of the dielectric substrate, and a ground pattern formed on the back surface of the dielectric substrate. A ground pattern formed so as to face each other, a passive element inserted in series in the transmission line, a first passive element connecting the transmission line and the ground pattern in parallel, the transmission line and the A second circuit that includes a second passive element that connects the ground pattern in parallel, and a first circuit that is formed between the transmission line and the ground pattern and that includes the first passive element is the transmission line; The configuration may be such that the second circuit including the second passive element, which is formed between the ground pattern and the second pattern, is equivalent.

  According to the above configuration, even when the transmission line and the ground pattern are arranged to face each other, the first circuit including the first passive element and the second circuit including the second passive element are provided. Can be configured equivalently. Therefore, the symmetry between the distribution of the current flowing from the transmission line to the first ground pattern and the distribution of the current flowing from the transmission line to the second ground pattern can be enhanced, and the symmetry of the voltage drop can be enhanced. .. As a result, noise superimposed on the high frequency signal can be suppressed.

  A high-frequency circuit board according to an aspect of the present invention includes a plurality of any of the high-frequency circuit modules, and a transmission line provided in each of the plurality of high-frequency circuit modules is a transmission line provided in another high-frequency circuit module. The first ground pattern that is connected to the line and that is provided in each of the plurality of high-frequency circuit modules is connected to the first ground pattern or the second ground pattern that is provided in the other high-frequency circuit module. The second ground pattern provided in each of the plurality of high-frequency circuit modules is connected to the first ground pattern or the second ground pattern provided in the other high-frequency circuit module. Is characterized by.

  With the above structure, the same effect as that of the high-frequency circuit module according to one aspect of the present invention can be obtained.

  INDUSTRIAL APPLICABILITY The present invention can suppress noise superimposed on a high frequency signal in a high frequency circuit module having a transmission line that transmits a high frequency signal.

It is a circuit diagram which shows the structure of the filter circuit which concerns on the 1st Embodiment of this invention. FIG. 3A is a top view showing the configuration of the filter circuit according to the first embodiment of the present invention. Each of (b) and (c) is a cross-sectional view taken along the line B-B 'and the line A-A' shown in (a). Each of (a) and (b) is a circuit diagram showing a configuration of a filter circuit according to an application example of the present invention. Each of (a) to (c) is a circuit diagram showing a configuration of a filter circuit according to another application example of the present invention. Each of (a) and (b) is a circuit diagram showing a configuration of a filter circuit according to still another application example of the present invention. (A) is a top view which shows the structure of the filter circuit which concerns on the 2nd Embodiment of this invention. (B) is a sectional view taken along the line C-C 'shown in (a). (C) is a circuit diagram showing a configuration of the filter circuit. (A) is a top view showing the composition of the filter circuit concerning the modification of a 2nd embodiment of the present invention. (B) is a circuit diagram showing a configuration of the filter circuit. FIG. 7A is a top view showing the configuration of the filter circuit according to the third embodiment of the present invention. (B) is a sectional view taken along the line D-D 'shown in (a). (C) is a circuit diagram showing a configuration of the filter circuit. (A) is a circuit diagram which shows the structure of the filter circuit which concerns on the 4th Embodiment of this invention. FIG. 3B is a top view showing the configuration of the filter circuit.

[First Embodiment]
A high frequency circuit module according to a first embodiment of the present invention will be described below with reference to the drawings. The high-frequency circuit module according to this embodiment includes a dielectric substrate, a signal line (transmission line), a ground pattern, and a passive element, and functions as a filter circuit. Hereinafter, the high frequency circuit module according to the present embodiment is referred to as a filter circuit. The filter circuit according to the present embodiment can be used alone or as one of a plurality of modules forming a high frequency circuit board that transmits a high frequency. In the latter case, the high frequency circuit board may be configured by combining a plurality of filter circuits according to the present embodiment, or the high frequency circuit board may be configured by combining the filter circuit according to the present embodiment with another module. Good.

(Circuit configuration of the filter circuit 10)
The circuit configuration of the filter circuit 10 according to the present embodiment will be described with reference to FIG. FIG. 1 is a circuit diagram showing the configuration of the filter circuit 10.

  As shown in FIG. 1, the filter circuit 10 includes a signal line 12, ground patterns 13 and 14, an inductor L1, and capacitors C1, C2, C3 and C4. The signal line 12 is an example of a transmission line, the inductor L1 is an example of a passive element inserted in series with the signal line 12, and the capacitors C1 and C2 connect the signal line 12 and the ground pattern 13 in parallel. The capacitors C3 and C4 are an example of a second passive element that connects the signal line 12 and the ground pattern 14 in parallel. The ground pattern 13 functions as a first ground pattern, and the ground pattern 14 functions as a second ground pattern.

  The first circuit 10a is a circuit configured inside the filter circuit 10, and is a circuit configured by the signal line 12, the ground pattern 13, the inductor L1, and the capacitors C1 and C2. The second circuit 10b is a circuit configured inside the filter circuit 10, and is a circuit configured by the signal line 12, the ground pattern 14, the inductor L1, and the capacitors C3 and C4.

  Specifically, the capacitor C1 is arranged on the input terminal IN side of the inductor L1 (hereinafter, simply referred to as the input side), and connects the signal line 12 and the ground pattern 13 to each other. The capacitor C2 is arranged on the output terminal OUT side of the inductor L1 (hereinafter, simply referred to as the output side), and connects the signal line 12 and the ground pattern 13 to each other. In other words, the capacitors C1 and C2 connect the signal line 12 and the ground pattern 13 in parallel. Similarly, the capacitors C3 and C4 are arranged on the input side and the output side of the inductor L1, respectively, and connect the signal line 12 and the ground pattern 14 in parallel.

  The capacitors C1 and C3 are connected to the input side of the inductor L1, and the capacitors C2 and C4 are connected to the output side of the inductor L1.

  As shown in FIG. 1, in the filter circuit 10, each of the capacitors C1 and C2 and each of the capacitors C3 and C4 are arranged line-symmetrically with respect to the signal line 12. The ground patterns 13 and 14 are arranged symmetrically with respect to the signal line 12, respectively. In the filter circuit 10 configured as above, the first circuit 10a is equivalent to the second circuit 10b.

  In the filter circuit 10, it is preferable that the component constant of the capacitor C1 and the component constant of the capacitor C3 are equal to each other, and the component constant of the capacitor C2 and the component constant of the capacitor C4 are equal to each other.

  As shown in FIG. 1, when the high frequency signal is input to the input terminal IN after the ground patterns 13 and 14 are grounded, the filter circuit 10 includes a low pass filter (LPF) for the high frequency signal transmitted by the signal line 12. ) And outputs a filtered high frequency signal from the output terminal OUT.

(Configuration of filter circuit 10)
Next, a specific configuration of the filter circuit 10 will be described with reference to FIG. FIG. 2 is a schematic diagram showing the configuration of the filter circuit 10. Specifically, FIG. 2A is a top view showing the configuration of the filter circuit 10. 2B is a cross-sectional view showing the configuration of the filter circuit 10, and is a cross-sectional view taken along the line BB ′ shown in FIG. 2C is a cross-sectional view showing the configuration of the filter circuit 10, and is a cross-sectional view taken along the line AA ′ shown in FIG.

  As shown in FIGS. 2A to 2C, the filter circuit 10 is manufactured using the dielectric substrate 11. Specifically, the signal line 12 is a conductor film formed on the surface 11a of the dielectric substrate 11, and the ground patterns 13 and 14 are a pair of ground patterns that sandwich the signal line 12 between them. 11 is a conductor film formed on the surface 11a. As described above, the ground patterns 13 and 14 are both grounded.

  It should be noted that examples of conductors forming the signal line 12 and the ground patterns 13 and 14 include copper and aluminum.

  As shown in FIG. 2A, the capacitors C1 to C4 and the ground patterns 13 and 14 that are each of the passive element groups are line-symmetric with respect to the signal line 12 when the dielectric substrate 11 is viewed in a plan view. It is arranged. More specifically, a straight line parallel to the extending direction of the signal line 12, which is a straight line passing through the center of the signal line 12 in the width direction, is taken as the axis of symmetry, and the capacitors C1 to C4 and the ground. The patterns 13 and 14 are arranged in line symmetry. In this specification, a straight line passing through the center of the signal line 12 in the width direction is referred to as a center line of the signal line 12.

  As described above, the capacitors C1 to C4 and the ground patterns 13 and 14 of the filter circuit 10 are arranged symmetrically with respect to the signal line 12 on the circuit diagram as shown in FIG. Also in the above, it is preferable that the dielectric substrate 11 is arranged in line symmetry with respect to the signal line 12 when seen in a plan view. It is more preferable that the capacitors C1 to C4 have the same shape and the ground patterns 13 and 14 have the same shape. The effect of this configuration will be described later as one of the effects of the filter circuit 10. In addition to the geometrical shapes of the passive element and the ground pattern when the dielectric substrate 11 is viewed in a plan view, the above-mentioned shape includes the line width, the line length, and the line width of the passive element and the ground pattern as parameters for determining the shape. The film thickness etc. are included.

  As shown in FIG. 2B, the capacitor C1 is arranged over the input side of the signal line 12 and the ground pattern 13, and connects the signal line 12 and the ground pattern 13. The capacitor C2 is arranged over the output side of the signal line 12 and the ground pattern 13, and connects the signal line 12 and the ground pattern 13. The capacitors C3 and C4 are configured similarly to the capacitors C1 and C2, and connect the signal line 12 and the ground pattern 14.

  As shown in FIG. 2C, the inductor L1 is arranged over the opposite ends of the bisected signal line 12, and connects the bisected signal line 12. That is, the inductor L1 is inserted in the signal line 12.

  Further, the filter circuit 10 is provided with a ground pattern 15 (back surface side ground pattern) which is a ground pattern formed on the back surface 11b of the dielectric substrate 11 and which is formed at least in a region facing the signal line 12. Like the ground patterns 13 and 14, the ground pattern 15 is preferably made of a conductor film and grounded.

  The ground pattern 15 prevents the electromagnetic waves existing outside the filter circuit 10 from being superimposed as noise on the high frequency signal transmitted by the signal line 12, and at the same time, the electromagnetic waves resulting from the high frequency signal become noise and become the filter circuit. The influence on the external circuit of 10 is suppressed. That is, the ground pattern 15 functions as a noise shielding layer. In order to shield noise from a wider range, the ground pattern 15 is a region including a region facing the signal line 12, and is preferably formed in a wider region, and is formed over the entire back surface 11b. Is more preferable.

  Although the filter circuit 10 is described as including the ground pattern 15 in the present embodiment, the present invention is not limited to this. That is, the ground pattern 15 may be omitted in the filter circuit 10.

  Further, in the present embodiment, the configuration in which the capacitors C1 to C4 and the ground patterns 13 and 14 are arranged in line symmetry with the center line of the signal line 12 as the axis of symmetry has been described as the best mode. However, the present invention is not limited to this. If the capacitors C1 to C4 and the ground patterns 13 and 14 are arranged in line symmetry with any of the straight lines parallel to the extending direction of the signal line 12 and overlapping with the signal line 12 as the axis of symmetry, The effect of suppressing the noise superimposed on the signal can be obtained.

  The filter circuit 10 configured as described above is a substrate type filter circuit that can be manufactured on the same dielectric substrate as the high frequency transmission substrate that transmits high frequencies. Further, the signal line and the ground pattern included in the high-frequency transmission board and the signal line 12 and the ground patterns 13 and 14 included in the filter circuit 10 can be collectively manufactured using the same manufacturing process. Therefore, the filter circuit 10 can be continuously connected to the high-frequency transmission board and can suppress unnecessary reflection at the input terminal IN and the output terminal OUT.

(Component constants of the filter circuit 10)
As a comparative example of the filter circuit 10, a filter circuit in which the capacitors C3 and C4 and the ground pattern 14 are removed from the configuration of the filter circuit 10 is assumed. The filter circuit according to this comparative example has a configuration equivalent to that of a conventionally known π-type filter.

  In order to determine the component constants of the inductor L1 and the capacitors C1 to C4 included in the filter circuit 10, the designer of the filter circuit 10 has a filter circuit according to a comparative example, that is, a component of a conventionally known π-type filter. Methods are available to determine the constant. Specifically, the component constants of the inductor L1 and the capacitors C1 to C4 may be determined as follows.

  Step S1: Determine specifications such as characteristic impedance and cutoff frequency to be realized by using the filter circuit 10.

  Step S2: Determine component constants for satisfying the specifications with the conventional π-type filter. In this step, the component constants (inductance and capacitance) of the inductor L1 and the capacitors C1 and C2 included in the conventional π-type filter are determined.

  Step S3: As the component constant of the capacitor C3, a component constant equal to the component constant of the capacitor C1 is adopted. As the component constant of the capacitor C4, the component constant equal to the component constant of the capacitor C2 is adopted.

  By making the component constant of the capacitor C1 and the component constant of the capacitor C3 equal and making the component constant of the capacitor C2 equal to the component constant of the capacitor C4, the symmetry of the current flowing from the signal line 12 to the ground patterns 13 and 14 is further improved. It is possible to increase the symmetry of the voltage drop.

(Effect of the filter circuit 10)
Compared with the filter circuit according to the comparative example described above, that is, a conventionally known π-type filter, the filter circuit 10 further includes capacitors C3 and C4 and a ground pattern 14, and capacitors C1 to C4 are included in the circuit diagram. And the ground patterns 13 and 14 are arranged symmetrically with respect to the signal line 12, and the capacitors C1 to C4 and the ground patterns 13 and 14 are arranged symmetrically with respect to the signal line 12 even in the real space. That is different.

  First, in the circuit diagram, the capacitors C1 to C4 and the ground patterns 13 and 14 are arranged symmetrically with respect to the signal line 12, so that the filter circuit 10 functions as an LPF like a conventional π-type filter. In addition to this, the effect of suppressing noise mixed in the high frequency signal transmitted by the signal line 12 is exerted.

  For example, in the filter circuit according to the comparative example, a high-frequency component other than the specific high-frequency component of the high-frequency transmission signal transmitted by the signal line is passed (neutralized) to the ground pattern via the capacitor to cause the high-frequency component specific to the signal line to be high. A high frequency signal having a component is transmitted. However, if there is a difference in potential difference between the signal line and the ground patterns on both sides of the signal line, the high-frequency component that has flowed through the ground pattern via the capacitor or the like is mixed into the signal line as noise.

  On the other hand, in the filter circuit 10 according to the present invention, the high frequency component of the high frequency signal transmitted by the signal line 12 similarly flows from the signal line 12 to each of the ground patterns 13 and 14 via the capacitors C1 to C4. Therefore, the potential difference generated between the signal line 12 and the ground pattern 13 and the potential difference generated between the signal line 12 and the ground pattern 14 are equal to or similar to each other. Therefore, an electric field generated between the ground pattern 13 and the ground pattern 14 can be suppressed, and as a result, noise mixed in the high frequency signal can be suppressed.

  Further, in the filter circuit 10, the capacitors C1 to C4 and the ground patterns 13 and 14 are arranged line-symmetrically with respect to the signal line 12, more specifically, the center line of the signal line 12 even in the real space. According to this configuration, the symmetry of the distribution of the current flowing from the signal line 12 to each of the ground patterns 13 and 14 via the capacitors C1 to C4 becomes higher, and the symmetry of the voltage drop can be further increased. Therefore, the electric field generated between the ground pattern 13 and the ground pattern 14 can be further suppressed, and as a result, the noise mixed in the high frequency signal can be further suppressed.

  The configuration of the filter circuit according to the present invention is not limited to the configuration of the filter circuit 10. In particular, the passive element (inductor L1) inserted in series in the signal line 12 and the passive element group (capacitors C1 to C4) connecting the signal line and the ground pattern in parallel are arranged according to the desired filter circuit configuration. Can be changed as appropriate. Various application examples of the filter circuit according to the present invention will be described later with reference to the accompanying drawings.

  Further, the transmission line of the filter circuit 10 is configured as a coplanar line including the signal line 12 and the ground patterns 13 and 14, but is not limited to this. The transmission line of the filter circuit according to the present invention can also be configured as a microstrip line including a signal line and a ground pattern that face each other with the dielectric substrate in between. This configuration will also be described later with reference to the drawings to which reference is also made.

[Application example]
A filter circuit according to an application example of the invention will be described below with reference to FIGS. FIGS. 3A and 3B are circuit diagrams respectively showing configurations of filter circuits 20 and 30 according to application examples of the present invention. 4A to 4C are circuit diagrams showing configurations of filter circuits 40, 50 and 60 according to other application examples of the present invention. 5A and 5B are circuit diagrams showing configurations of filter circuits 70 and 80 according to still another application example of the present invention.

  Note that each of the filter circuits 20 to 80 can be manufactured by forming the signal line 12 and the ground patterns 13 and 14 on the surface of the dielectric substrate, similarly to the filter circuit 10 according to the first embodiment. .. The signal line 12 and the ground patterns 13 and 14 have the same configuration as that of the filter circuit 10, and therefore their description is omitted.

  As shown in FIG. 3A, the filter circuit 20 employs two inductors L21 and L22 connected in series as passive elements inserted in series in the signal line 12. Further, the filter circuit 20 employs capacitors C21 and C22 as a passive element group that connects the signal line 12 and the ground patterns 13 and 14 in parallel. The capacitors C21, C22 and the ground patterns 13, 14 are arranged symmetrically with respect to the signal line 12 in the circuit diagram. The capacitor C21 is connected to an intermediate point between the inductor L21 and the inductor L22 and the ground pattern 13. The capacitor C22 is connected to the ground point 14 and the intermediate point between the inductor L21 and the inductor L22.

  As shown in FIG. 3B, the filter circuit 30 employs the inductor L31 as a passive element inserted in series with the signal line 12. Further, the filter circuit 30 employs capacitors C31 and C32 as a passive element group that connects the signal line 12 and the ground patterns 13 and 14 in parallel. The capacitors C31, C32 and the ground patterns 13, 14 are arranged symmetrically with respect to the signal line 12 in the circuit diagram. The capacitor C31 is connected to the output side of the inductor L31 and the ground pattern 13. The capacitor C32 is connected to the output side of the inductor L31 and the ground pattern 14.

  Although the capacitors C31 and C32 are described here as being connected to the output side of the inductor L31, they may be connected to the input side of the inductor L31. That is, the capacitors C31 and C32 may be connected to the same one of the input side and the output side of the inductor L31.

  Each of the filter circuits 20 and 30 configured as described above functions as an LPF. Further, in each of the filter circuits 20 and 30, the respective capacitors and the ground patterns 13 and 14 which are the passive element groups are line-symmetric with respect to the signal line 12, more specifically, the center line of the signal line 12 in the real space. Are preferably arranged in

  As another application example, as shown in FIG. 4A, the filter circuit 40 employs the capacitor C41 as a passive element inserted in series with the signal line 12, and the signal line 12 and the ground pattern 13, Inductors L41, L42, L43, and L44 are adopted as a passive element group for connecting 14 and 14 in parallel. The filter circuit 40 is obtained by replacing the inductor L1 and the capacitors C1 to C4 of the filter circuit 10 according to the first embodiment with a capacitor C41 and inductors L41 to L44, respectively.

  As shown in FIG. 4B, the filter circuit 50 employs two capacitors C51 and C52 connected in series as passive elements inserted in series in the signal line 12, and as a passive element group. Inductors L51 and L52 are used. The filter circuit 50 is obtained by replacing the inductors L21 and L22 and the capacitors C21 and C22 of the filter circuit 20 according to the application example of the present invention with capacitors C51 and C52 and inductors L51 and L52, respectively.

  As shown in (c) of FIG. 4, the filter circuit 60 employs a capacitor C61 as a passive element inserted in series to the signal line 12, and adopts inductors L61 and L62 as each of the passive element groups. ing. The filter circuit 60 is obtained by replacing the inductor L31 and the capacitors C31 and C32 of the filter circuit 30 according to the application example of the present invention with a capacitor C61 and inductors L61 and L62, respectively.

  In each of the filter circuits 40, 50 and 60 configured as described above, the inductors and the ground patterns 13 and 14 which are passive element groups are arranged symmetrically with respect to the signal line 12 in the circuit diagram. In addition, in each of the filter circuits 40, 50, and 60, the inductors and the ground patterns 13 and 14 that are the passive element groups are located in the real space with respect to the signal line 12, more specifically, the center line of the signal line 12. It is preferable that they are arranged in line symmetry.

  Each of the filter circuits 40, 50, 60 configured as described above functions as a high pass filter (HPF).

  As still another application example, as shown in FIG. 5A, the filter circuit 70 employs an inductor L71 and a capacitor C71 connected in series as passive elements inserted in series in the signal line 12. Therefore, inductors L72, L73, L74, L75 and capacitors C72, C73, C74, C75 are adopted as the passive element group. Each of the passive element groups includes a set of an inductor and a capacitor (for example, an inductor L72 and a capacitor C72) connected in parallel.

  The filter circuit 70 replaces the inductor L1 of the filter circuit 10 according to the first embodiment with an inductor L71 and a capacitor C71 that are connected in series, and replaces each of the capacitors C1 to C4 with a pair of capacitors that are connected in parallel. It is replaced with an inductor and a capacitor.

  The filter circuit 70 configured as described above functions as a bandpass filter (BPF).

  As shown in FIG. 5B, the filter circuit 80 employs an inductor L81 and a capacitor C81 connected in parallel as passive elements inserted in the signal line 12, and an inductor L82 as a passive element group. , L83, L84, L85 and capacitors C82, C83, C84, C85. Each of the passive element groups includes a set of an inductor and a capacitor (for example, an inductor L82 and a capacitor C82) connected in series.

  The filter circuit 80 replaces the inductor L1 of the filter circuit 10 according to the first embodiment with an inductor L81 and a capacitor C81 which are connected in parallel, and each of the capacitors C1 to C4 is connected in series. It is replaced with an inductor and a capacitor.

  The filter circuit 80 configured as described above functions as a band elimination filter (BEF).

  In each of the filter circuits 70 and 80 configured as described above, the inductors and capacitors that are passive element groups, and the ground patterns 13 and 14 are arranged symmetrically with respect to the signal line 12 in the circuit diagram. ing. In each of the filter circuits 70 and 80, the inductors and capacitors that are the passive element groups, and the ground patterns 13 and 14 have the signal line 12 in the real space, more specifically, the center line of the signal line 12. It is preferable that they are arranged in line symmetry with respect to.

  In the filter circuits 70 and 80, the passive element group is described as being arranged on both the input side and the output side of the passive element inserted in the signal line 12, but the present invention is not limited to this. If the passive element group is connected to at least one of the input side and the output side of the passive element inserted in the signal line 12 (the same side if there is either one), the filter circuit 70 and the filter circuit 80. Respectively function as BPF and BEF.

  Further, one filter circuit may be configured by connecting each of the filter circuits 10 to 80 according to the first embodiment and the application example in a plurality of stages.

  Further, each of the filter circuits 10 to 80 is an LC filter including an inductor and a capacitor, but the present invention is not limited to this. The present invention can be applied to, for example, an RC filter including a capacitor and a resistor, and can also be applied to an attenuator including a resistor. When the present invention is applied to the RC filter, the inductor L1 of the filter circuit 10 may be replaced with a resistor. When the present invention is applied to the attenuator, each of the inductor L1 and the capacitors C1 to C4 of the filter circuit 10 may be replaced with a resistor. The attenuator is a kind of filter because it attenuates the amplitude of the high frequency signal in the entire frequency band.

  In addition, each of the filter circuits 10 to 80 employs one or two passive elements as a passive element inserted in the signal line 12 and a passive element group connected in parallel to the signal line 12. However, the present invention is not limited to this. That is, each passive element inserted in the signal line 12 and each passive element group connected in parallel to the signal line 12 may have a configuration including three or more passive elements.

[Second Embodiment]
A high frequency circuit module according to a second embodiment of the present invention will be described below with reference to the drawings. The high-frequency circuit module according to the present embodiment is composed of a dielectric substrate, a signal line (transmission line), a ground pattern, and a passive element, like the high-frequency circuit module according to the first embodiment, and functions as a filter circuit. To do. Hereinafter, the high frequency circuit module according to the present embodiment is referred to as a filter circuit.

  The filter circuit 90 according to this embodiment will be described below with reference to FIG. The same members as those of the filter circuit 10 according to the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. FIG. 6A is a top view showing the configuration of the filter circuit 90. 6B is a cross-sectional view showing the configuration of the filter circuit 90, which is a cross-sectional view taken along the line C-C ′ shown in FIG. FIG. 6C is a circuit diagram showing the configuration of the filter circuit 90.

(Short-circuit post group)
As shown in FIGS. 6A and 6B, the filter circuit 90 differs from the filter circuit 10 in that the filter circuit 90 includes short-circuit post groups 96 a to 96 d. The short-circuit post groups 96a to 96d correspond to the short-circuit path group described in the claims. Each of the short-circuit post groups 96a to 96d is a columnar post made of a conductor and formed along the inner wall of a through hole provided in the dielectric substrate 91.

  The short-circuit post groups 96a to 96d short-circuit each of the ground pattern 13 and the ground pattern 14 formed on the front surface of the dielectric substrate 91 and the ground pattern 15 which is a back surface side ground pattern formed on the back surface of the dielectric substrate. Let

  As shown in (c) of FIG. 6, in the circuit diagram, each of the capacitors C1 to C4 and the ground patterns 13 and 14 are arranged symmetrically with respect to the signal line 12. Even in the real space, as shown in FIG. 6A, each of the capacitors C1 to C4 and the ground patterns 13 and 14 are line-symmetric with respect to the signal line 12, more specifically, the center line of the signal line 12. Are preferably arranged in

  Similar to the filter circuit 10, the filter circuit 90 includes a first circuit 90a and a second circuit 90b. The first circuit 90a is a circuit formed between the signal line 12 and the ground pattern 13 and includes capacitors C1 and C2. The second circuit 90b is a circuit formed between the signal line 12 and the ground pattern 14 and includes capacitors C3 and C4. In the filter circuit 90, the first circuit 90a is equivalent to the second circuit 90b.

  According to the above configuration, the ground pattern 13 and the ground pattern 14 are short-circuited via the short-circuit post groups 96a to 96d and the ground pattern 15, so that the potential difference generated between the ground pattern 13 and the ground pattern 14 is further reduced. Can be suppressed. In particular, even when the areas of the ground pattern 13 and the ground pattern 14 are different, they are short-circuited via the short-circuit post groups 96a to 96d and the ground pattern 15, so that the ground pattern 13 and the ground pattern 14 are The potential difference generated between the two is suppressed.

  Therefore, the filter circuit 90 can further suppress the noise superimposed on the high frequency signal transmitted by the signal line 12.

  Further, as shown in FIG. 6A, the short circuit post groups 96a to 96d may be provided at positions symmetrical with respect to the signal line 12, more specifically, the center line of the signal line 12. preferable. With this configuration, the symmetry of the distribution of the current flowing from the signal line 12 to the ground pattern 15 can be further enhanced.

(Single point ground)
In the filter circuit 90, it is preferable that the capacitors C1 to C4 and the groups of short-circuit posts 96a to 96d are arranged in a circle having a radius of 0.1 × λe, where λe is the effective wavelength of the high-frequency signal transmitted by the signal line. .. A circle S1 indicated by a broken line in (a) of FIG. 6 represents a circle having a radius of 0.1 × λe.

  By arranging the short circuit post groups 96a to 96d in the immediate vicinity of the capacitors C1 to C4, the capacitors C1 to C4 and the short circuit post groups 96a to 96d can be arranged in the circle S1. With this configuration, the ground of the filter circuit 90 can be regarded as a single-point ground, and the potential of the ground pattern 13 and the potential of the ground pattern 14 can be precisely matched. In other words, the potential difference generated between the ground pattern 13 and the ground pattern 14 can be eliminated. Therefore, the transmission line composed of the signal line 12 and the ground patterns 13 and 14 can be further functioned as a transmission line.

(Modification)
A filter circuit 901 according to a modified example of the filter circuit 90 will be described below with reference to FIG. 7. The same members as those of the filter circuit 90 are designated by the same reference numerals and the description thereof will be omitted. FIG. 7A is a top view showing the configuration of the filter circuit 901. FIG. 7B is a circuit diagram showing the configuration of the filter circuit 901.

  The filter circuit 901 is different from the filter circuit 90 in the arrangement of the capacitors C1 to C4 and the short-circuit post groups 961a and 961b. The short-circuit post groups 961a and 961b correspond to the short-circuit path group described in the claims. The dielectric substrate 911 is different from the dielectric substrate 91 in the position where the through hole is provided.

  Specifically, the capacitors C1 and C2 are arranged such that the interval between the capacitors C1 and C2 becomes narrower as the signal line 12 approaches the ground pattern 13. The shorting post 961a is provided in a region where the region where the capacitor C1 extends in the longitudinal direction and the region where the capacitor C2 extends in the longitudinal direction overlap.

  The capacitors C3 and C4 and the shorting post 961b are configured similarly to the capacitors C1 and C2 and the shorting post 961a.

  Similar to the filter circuit 90, the filter circuit 901 is provided with a first circuit 901a and a second circuit 901b. The first circuit 901a is a circuit formed between the signal line 12 and the ground pattern 13 and includes capacitors C1 and C2. The second circuit 901b is a circuit formed between the signal line 12 and the ground pattern 14 and includes capacitors C3 and C4. In the filter circuit 901, the first circuit 901a is equivalent to the second circuit 901b.

  According to this configuration, the capacitors C1 to C4 and the short-circuit post groups 961a and 961b can be arranged within a narrower range than the filter circuit 90 (see FIG. 7A). Therefore, the ground of the filter circuit 901 can be regarded as a better one-point ground.

[Third Embodiment]
A high frequency circuit module according to a third embodiment of the present invention will be described below with reference to the drawings. The high-frequency circuit module according to the present embodiment is composed of a dielectric substrate, a signal line (transmission line), a ground pattern, and a passive element, like the high-frequency circuit module according to the first embodiment, and functions as a filter circuit. To do. Hereinafter, the high frequency circuit module according to the present embodiment is referred to as a filter circuit.

  When the resistors R101, R102, R103, and R104 are adopted as the passive element group that connects the signal line 12c and the ground patterns 113 and 116 in parallel, the resistance is 1/2 as compared with the resistors used in the conventional π type. To adopt the one.

  The filter circuit 902 according to this embodiment will be described below with reference to FIG. The filter circuit 902 has a configuration obtained by transforming the ground patterns 13 and 14 of the filter circuit 90 according to the second embodiment into short-circuit pads 932 and 942. Therefore, in this embodiment, the same members as those of the filter circuit 90 are designated by the same reference numerals, and the description thereof will be omitted.

  FIG. 8A is a top view showing the configuration of the filter circuit 902. 8B is a cross-sectional view showing the configuration of the filter circuit 902, which is a cross-sectional view taken along the line D-D ′ shown in FIG. FIG. 8C is a circuit diagram showing the configuration of the filter circuit 902.

  As shown in FIG. 8C, the filter circuit 902 includes a signal line 12, a ground pattern 95 that replaces the ground pattern 15, an inductor L1 that is a passive element inserted in series with the signal line 12, and a signal. It is provided with capacitors C1 to C4 which are passive element groups for connecting the line 12 and the ground pattern 95 in parallel.

  The capacitors C1 and C2 are short-circuited to the ground pattern 95 via the short-circuit pad 932 and the short-circuit post groups 96a and 96b. Similarly, the capacitors C3 and C4 are short-circuited to the ground pattern 95 via the short-circuit pad 942 and the short-circuit post groups 96c and 96d. The capacitors C1 to C4 and the ground pattern 95 of the filter circuit 902 thus configured are arranged symmetrically with respect to the signal line 12 in the circuit diagram shown in FIG.

  Like the filter circuit 10, the filter circuit 902 is provided with a first circuit 902a and a second circuit 902b. The first circuit 902a is a circuit formed between the signal line 12 and the ground pattern 13 and includes capacitors C1 and C2. The second circuit 902b is a circuit formed between the signal line 12 and the ground pattern 14 and includes capacitors C3 and C4. In the filter circuit 902, the first circuit 90a is equivalent to the second circuit 90b.

  Next, a specific configuration of the filter circuit 902 will be described with reference to FIGS. 8A and 8B.

  As shown in FIGS. 8A and 8B, the signal line 12 is a conductor film formed on the surface 91 a of the dielectric substrate 91. The ground pattern 95 is a conductor film formed on the back surface 91b of the dielectric substrate 91 so as to face the signal line 12.

  The short-circuit pad 932 is a conductor film formed on the surface of the dielectric substrate 91 and short-circuits the capacitors C1 and C2. The short-circuit pad 932 is connected to the ground pattern 95 via short-circuit post groups 96a and 96b formed on the lower side of the short-circuit pad 932.

  It is sufficient that short-circuit pad 932 can fix capacitors C1 and C2 to the surface of dielectric substrate 91 with sufficient strength, and does not necessarily directly short-circuit capacitors C1 and C2. That is, the short-circuit pad 932 may be composed of two conductor films that individually fix the capacitors C1 and C2.

  The short-circuit pad 942 is configured similarly to the short-circuit pad 932.

  In the filter circuit 902, the capacitors C1 to C4 and the ground pattern 95 are line-symmetric with respect to the signal line 12, more specifically, the center line of the signal line 12 in the real space as shown in FIG. 8A. Are preferably arranged in

  Further, it is preferable that the short-circuit pad 932 and the short-circuit pad 942 are arranged in line symmetry with respect to the signal line 12, more specifically, the center line of the signal line 12 even in the real space. With this configuration, the symmetry of the distribution of the current flowing from the signal line 12 to the ground pattern 95 via the short-circuit pads 932 and 942 can be enhanced, and the symmetry of the voltage drop can be enhanced.

  A circle S1 indicated by a broken line in (a) of FIG. 8 represents a circle having a radius of 0.1 × λe. As shown in FIG. 8A, the capacitors C1 to C4 and the short-circuit post groups 96a to 96d are preferably arranged in a circle S1. With this configuration, the ground of the filter circuit 90 can be regarded as a one-point ground.

  The filter circuit 902 configured as above has the same effect as the filter circuit 90 according to the second embodiment.

[Fourth Embodiment]
A high frequency circuit board according to a fourth embodiment of the present invention will be described below with reference to the drawings. The high-frequency circuit board according to the present embodiment is a high-frequency circuit board including a plurality of high-frequency circuit modules that are application examples of the first embodiment.

  The high-frequency circuit board according to the present embodiment includes a plurality of high-frequency circuit modules described in any of the first to third embodiments, and the transmission lines provided in each of the plurality of high-frequency circuit modules are different from each other. The first ground pattern, which is connected to the transmission line provided in the high-frequency circuit module and is provided in each of the plurality of high-frequency circuit modules, is the first ground pattern provided in the other high-frequency circuit module. Alternatively, the second ground pattern, which is connected to the second ground pattern and is provided in each of the plurality of high-frequency circuit modules, is the first ground pattern or the second ground pattern provided in the other high-frequency circuit module. It is connected to the ground pattern.

  A high frequency circuit board 110, which is a specific example of the high frequency circuit board according to the present embodiment, will be described below with reference to FIG. 9. FIG. 9A is a circuit diagram showing the configuration of the high-frequency circuit board 110. FIG. 9B is a top view showing the configuration of the high-frequency circuit board 110.

  The high-frequency circuit board 110 has a configuration obtained by combining the filter circuit 30, the filter circuit 40, and the attenuator 100, which are application examples of the first embodiment, and includes a signal line 12a, capacitors C31 and C32, an inductor L31, and a signal. The line 12b, the capacitor C41, the inductors L41 to L44, the signal line 12c, the resistors R101 to R105, and the ground patterns 113, 114, and 116 are provided.

  The filter circuit 30 employs the inductor L31 as a passive element inserted in series with the signal line 12a. Further, the filter circuit 30 employs capacitors C32 and 31 as a passive element group that connects the signal line 12a and the ground patterns 114 and 116 in parallel. The signal line 12a, the ground pattern 116, the inductor L31, and the capacitor C31 form a first circuit of the filter circuit 30. The signal line 12a, the ground pattern 114, the inductor L31, and the capacitor C32 form a second circuit of the filter circuit 30. In the filter circuit 30, the first circuit and the second circuit are equivalent.

  The filter circuit 40 employs the capacitor C41 as a passive element inserted in series with the signal line 12b. Further, the filter circuit 40 employs the inductors L41 to L44 as a passive element group that connects the signal line 12b and the ground patterns 113 and 114 in parallel. The signal line 12b, the ground pattern 113, the capacitor C41, and the inductors L41 and L42 form a first circuit of the filter circuit 40. Further, the signal line 12b, the ground pattern 114, the capacitor C41, and the inductors L43 and L44 form a second circuit of the filter circuit 40. In the filter circuit 40, the first circuit and the second circuit are equivalent.

  The attenuator 100 employs the resistor R105 as a passive element inserted in series with the signal line 12c. Further, the attenuator 100 employs resistors R101, R102, R103, R104 as a passive element group that connects the signal line 12c and the ground patterns 113, 116 in parallel. The signal line 12c, the ground pattern 113, the resistor R105, and the resistors R101 and R102 form a first circuit of the attenuator 100. Further, the signal line 12c, the ground pattern 116, the resistor R105, and the resistors R103 and R104 form a second circuit of the attenuator 100. In the attenuator 100, the first circuit and the second circuit are equivalent.

  In the high frequency circuit 110, the filter circuit 30, the filter circuit 40, and the attenuator 100 are connected as follows, as shown in FIG. That is, in the high-frequency circuit board 110, the signal line 12a is connected to the signal line 12b, and the signal line 12c is connected to the connection point between the signal line 12a and the signal line 12b. In other words, the output terminal of the signal line 12b of the filter circuit 40 is connected to the input terminal of the signal line 12c of the attenuator 100, and the signal line 12a of the filter circuit 30 is connected to the signal line 12b and the signal line 12c. Connected to the department.

  The ground pattern 113 functions as a first ground pattern in the filter circuit 40 and also functions as a first ground pattern in the attenuator 100. The ground pattern 114 functions as a second ground pattern in the filter circuit 40 and also functions as a second ground pattern in the filter circuit 30. The ground pattern 116 functions as a first ground pattern in the filter circuit 30 and a second ground pattern of the attenuator 100.

  When the ground patterns 113, 114 and 116 are grounded to the ground, a high frequency signal is input to the input terminal IN of the high frequency circuit board 110 and a DC power supply is connected to the power supply terminal Vcc of the high frequency circuit board 110, the filter circuit 30 functions as an LPF for the DC current transmitted by the signal line (transmission line) 12a, the filter circuit 40 functions as an HPF for the high frequency signal transmitted by the signal line 12b, and the attenuator 100 transmits by the signal line 12c. Functions as an attenuator for high frequency signals. Therefore, from the output terminal OUT of the high frequency circuit board 110, a high frequency signal subjected to HPF and attenuator is output.

  In the high frequency circuit board 110 shown in FIG. 9, a capacitor 121 is inserted in series on the input terminal side of the signal line 12b of the high frequency circuit board 110, and on the output terminal side of the signal line 12b of the high frequency circuit board 110. The capacitor C122 and the amplifier A121 are inserted in series. The capacitors C121 and C122 block the DC component contained in the high frequency signal transmitted by the signal line 12b, and the amplifier A121 amplifies the high frequency signal transmitted by the signal line 12b. Thus, the capacitors C121 and C122 and the amplifier A121 that are serially inserted in the signal line 12b do not affect the symmetry of the distribution of the current that flows from the signal line 12b to the ground patterns 113 and 114, and make the voltage drop symmetrical. Does not affect.

  Further, in the high frequency circuit board 110 shown in FIG. 9, a capacitor C123 is inserted in series on the input terminal side of the signal line 12c of the high frequency circuit board 110, and on the output terminal side of the signal line 12c of the high frequency circuit board 110, The capacitor C124 is inserted in series. The capacitors C123 and C124 block the DC component contained in the high frequency signal transmitted by the signal line 12c. Thus, the capacitors C123 and C124 inserted in series in the signal line 12c do not affect the symmetry of the distribution of the current flowing from the signal line 12c to the ground patterns 113 and 114, and also affect the symmetry of the voltage drop. Don't give

  As described above, at least one of the capacitor, the inductor, the resistor, and the amplifier may be inserted in series to at least one of the signal lines 12a, 12b, and 12c of the high-frequency circuit board 110.

  In the high-frequency circuit board 110, the filter circuits 30 and 40 and the attenuator 100 are used as each of the plurality of high-frequency modules, and a configuration in which they are connected as shown in FIG. 9 is adopted. However, the configuration of each of the plurality of high frequency modules and the connection mode thereof can be appropriately selected in order to achieve a desired high frequency transmission characteristic.

  The present invention is not limited to each of the above-described embodiments, and various modifications can be made within the scope of the claims, and an implementation obtained by appropriately combining the technical means disclosed in each of the different embodiments. The form is also included in the technical scope of the present invention.

  INDUSTRIAL APPLICATION This invention can be utilized for the high frequency circuit module which has the transmission line which transmits a high frequency signal, and the high frequency circuit board provided with the several high frequency circuit module.

10 Filter circuit (high frequency circuit module)
10a 1st circuit 10b 2nd circuit 11 Dielectric substrate 12 Signal line (transmission line)
13 ground patterns (first ground pattern)
14 ground patterns (second ground pattern)
15 Ground pattern (Back side ground pattern)
L1 inductor (passive element)
C1, C2 capacitors (first passive element)
C3, C4 capacitors (second passive element)
20, 30, 40, 50, 60, 70, 80 Filter circuit (high frequency circuit module)
20a, 30a, 40a, 50a, 60a, 70a, 80a First circuit 20b, 30b, 40b, 50b, 60b, 70b, 80b Second circuit L21, L22, L31 Inductor (passive element)
C21, C31 capacitors (first passive element)
C22, C32 capacitors (second passive element)
L41, L42, L51, L61 inductor (first passive element)
L43, L44, L52, L62 inductor (second passive element)
C41, C51, C52, C61 capacitors (passive elements)
L71, L81 Inductor (passive element)
C71, C81 capacitors (passive elements)
L72, L73, L82, L83 Inductor (first passive element)
L74, L75, L84, L85 inductor (second passive element)
C72, C73, C82, C83 Capacitor (first passive element)
C74, C75, C84, C85 capacitors (second passive element)
90,901,902 filter circuit (high frequency circuit module)
90a, 901a, 902a 1st circuit 90b, 901b, 902b 2nd circuit 91,911 Dielectric substrate 932,942 Short circuit pad 95 Ground pattern 96a, 96b, 96c, 96d, 961a, 961b Short circuit post group (short circuit path group) )
100 Attenuator (high frequency circuit module)
110 High-frequency circuit board R105 Resistor (passive element)
R101, R102 resistance (first passive element)
R103, R104 resistance (second passive element)
113,114,116 ground pattern

Claims (16)

A dielectric substrate,
A transmission line formed on the surface of the dielectric substrate,
First and second ground patterns formed on the surface, the first and second ground patterns sandwiching the transmission line and each made of a single conductor film,
A passive element inserted in series with the transmission line,
A first passive element that connects the transmission line and the first ground pattern in parallel;
A second passive element for connecting the transmission line and the second ground pattern in parallel,
A first circuit configured by the transmission line, the first ground pattern, the passive element, and the first passive element includes the transmission line, the second ground pattern, the passive element, and the first element. second circuit equivalent der constituted by two passive element is,
The first ground pattern and the second ground pattern are arranged in line symmetry with respect to the transmission line when the dielectric substrate is viewed in a plan view, and
The first passive element and the second passive element are arranged in line symmetry with respect to the transmission line when the dielectric substrate is viewed in a plan view,
A ground pattern facing the transmission line, a back surface side ground pattern formed on the back surface of the dielectric substrate,
Further comprising a short circuit path group for short-circuiting each of the first ground pattern and the second ground pattern and the back surface side ground pattern,
Let λe be the effective wavelength of the high-frequency signal transmitted by the transmission line,
In a plan view of the dielectric substrate, the first passive element, the second passive element, and the short circuit path group are arranged in a circle having a radius of 0.1 × λe.
A high-frequency circuit module characterized in that The component constant of the first passive element and the component constant of the second passive element are equal to each other,
The high frequency circuit module according to claim 1, wherein: The shape of the first ground pattern and the shape of the second ground pattern are equal to each other,
The high frequency circuit module according to claim 1 or 2 , characterized in that. In a plan view of the dielectric substrate, the short circuit path group is arranged line-symmetrically with respect to the transmission line,
The high frequency circuit module according to any one of claims 1 to 3, wherein The shape of the first passive element and the shape of the second passive element are equal to each other,
High-frequency circuit module according to any one of claims 1 to 4, characterized in that. The passive element comprises an inductor or a capacitor,
Each of the first passive element and the second passive element is
When the passive element consists of an inductor, it consists of a capacitor,
When the passive element consists of a capacitor, it consists of an inductor,
The first passive element and the second passive element are connected to at least one of an input side and an output side of the passive element,
High-frequency circuit module according to any one of claim 1 to 5, characterized in that. The first passive element and the second passive element are arranged on an input side and an output side of the passive element,
The high frequency circuit module according to claim 6 , wherein: A dielectric substrate,
A transmission line formed on the surface of the dielectric substrate,
First and second ground patterns formed on the surface, the first and second ground patterns sandwiching the transmission line and each made of a single conductor film,
A passive element inserted in series with the transmission line,
A first passive element that connects the transmission line and the first ground pattern in parallel;
A second passive element for connecting the transmission line and the second ground pattern in parallel,
A first circuit configured by the transmission line, the first ground pattern, the passive element, and the first passive element includes the transmission line, the second ground pattern, the passive element, and the first element. Equivalent to a second circuit composed of two passive elements,
The passive element comprises an inductor and a capacitor connected in series or in parallel,
Each of the first passive element and the second passive element is
When the passive element consists of an inductor and a capacitor connected in series, consisting of an inductor and a capacitor connected in parallel,
When the passive element consists of an inductor and a capacitor connected in parallel, consisting of an inductor and a capacitor connected in series,
The first passive element and the second passive element are connected to at least one of an input side and an output side of the passive element,
High frequency circuit module that wherein a. The first passive element and the second passive element are arranged on an input side and an output side of the passive element,
The high frequency circuit module according to claim 8 , wherein A dielectric substrate,
A transmission line formed on the surface of the dielectric substrate,
First and second ground patterns formed on the surface, the first and second ground patterns sandwiching the transmission line and each made of a single conductor film,
A passive element inserted in series with the transmission line,
A first passive element that connects the transmission line and the first ground pattern in parallel;
A second passive element for connecting the transmission line and the second ground pattern in parallel,
A first circuit configured by the transmission line, the first ground pattern, the passive element, and the first passive element includes the transmission line, the second ground pattern, the passive element, and the first element. Equivalent to a second circuit composed of two passive elements,
The passive element consists of two inductors or capacitors connected in series,
Each of the first passive element and the second passive element is
If the passive element is two inductors connected in series, it consists of a capacitor,
If the passive element is two capacitors connected in series, it consists of an inductor,
The first passive element and the second passive element are arranged at an intermediate point between the two inductors or capacitors,
High frequency circuit module that wherein a. A dielectric substrate,
A transmission line formed on the surface of the dielectric substrate,
First and second ground patterns formed on the surface, the first and second ground patterns sandwiching the transmission line;
A back surface side ground pattern facing the transmission line, the back surface side ground pattern formed on the back surface of the dielectric substrate,
A short circuit path group that short-circuits each of the first ground pattern and the second ground pattern with the back surface side ground pattern;
A passive element inserted in series with the transmission line,
A first passive element that connects the transmission line and the first ground pattern in parallel;
A second passive element for connecting the transmission line and the second ground pattern in parallel,
A first circuit configured by the transmission line, the first ground pattern, the passive element, and the first passive element includes the transmission line, the second ground pattern, the passive element, and the first element. Equivalent to a second circuit composed of two passive elements,
The first ground pattern and the second ground pattern are arranged in line symmetry with respect to the transmission line when the dielectric substrate is viewed in a plan view, and
The first passive element and the second passive element are arranged in line symmetry with respect to the transmission line when the dielectric substrate is viewed in a plan view,
Let λe be the effective wavelength of the high-frequency signal transmitted by the transmission line,
In a plan view of the dielectric substrate, the first passive element, the second passive element, and the short circuit path group are arranged in a circle having a radius of 0.1 × λe.
A high-frequency circuit module characterized in that A dielectric substrate,
A transmission line formed on the surface of the dielectric substrate,
First and second ground patterns formed on the surface, the first and second ground patterns sandwiching the transmission line;
A passive element inserted in series with the transmission line,
A first passive element that connects the transmission line and the first ground pattern in parallel;
A second passive element for connecting the transmission line and the second ground pattern in parallel,
A first circuit configured by the transmission line, the first ground pattern, the passive element, and the first passive element includes the transmission line, the second ground pattern, the passive element, and the first element. Equivalent to a second circuit composed of two passive elements,
The passive element consists of two inductors or capacitors connected in series,
Each of the first passive element and the second passive element is
If the passive element is two inductors connected in series, it consists of a capacitor,
If the passive element is two capacitors connected in series, it consists of an inductor,
The first passive element and the second passive element are arranged at an intermediate point between the two inductors or capacitors,
A high-frequency circuit module characterized in that A dielectric substrate,
A transmission line formed on the surface of the dielectric substrate,
A back surface side ground pattern formed on the back surface of the dielectric substrate, the back surface side ground pattern formed to face the transmission line,
A passive element inserted in series with the transmission line,
A first passive element that connects the transmission line and the back-side ground pattern in parallel;
A second passive element that connects the transmission line and the back-side ground pattern in parallel,
The first circuit including the first passive element formed between the transmission line and the back side ground pattern is formed between the transmission line and the back side ground pattern. Equivalent to a second circuit including two passive elements,
The passive element consists of two inductors or capacitors connected in series,
Each of the first passive element and the second passive element is
If the passive element is two inductors connected in series, it consists of a capacitor,
If the passive element is two capacitors connected in series, it consists of an inductor,
The first passive element and the second passive element are arranged at an intermediate point between the two inductors or capacitors,
A high-frequency circuit module characterized in that First and second ground patterns formed on the surface, the first and second ground patterns sandwiching the transmission line;
A first passive element that connects the transmission line and the first ground pattern in parallel;
Further comprising a second passive element that connects the transmission line and the second ground pattern in parallel,
The first ground pattern and the second ground pattern are arranged in line symmetry with respect to the transmission line when the dielectric substrate is viewed in a plan view, and
The first passive element and the second passive element are arranged line-symmetrically with respect to the transmission line when the dielectric substrate is viewed in plan.
The high frequency circuit module according to claim 13 , wherein: A plurality of high-frequency circuit module according to any one of claim 1 to 12 14,
The transmission line provided in each of the plurality of high-frequency circuit modules is connected to the transmission line provided in the other high-frequency circuit module,
The first ground pattern provided in each of the plurality of high-frequency circuit modules is connected to the first ground pattern or the second ground pattern provided in the other high-frequency circuit module,
The second ground pattern provided on each of the plurality of high-frequency circuit modules is connected to the first ground pattern or the second ground pattern provided on another high-frequency circuit module,
A high frequency circuit board characterized by the above. A plurality of high-frequency circuit modules according to claim 13 or 14 ,
The transmission line provided in each of the plurality of high-frequency circuit modules is connected to the transmission line provided in the other high-frequency circuit module,
The back side ground pattern provided in each of the plurality of high frequency circuit modules is connected to the back side ground pattern provided in the other high frequency circuit module,
A high frequency circuit board characterized by the above.

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