CN216354707U - Circuit board and antenna module - Google Patents
Circuit board and antenna module Download PDFInfo
- Publication number
- CN216354707U CN216354707U CN202090000404.XU CN202090000404U CN216354707U CN 216354707 U CN216354707 U CN 216354707U CN 202090000404 U CN202090000404 U CN 202090000404U CN 216354707 U CN216354707 U CN 216354707U
- Authority
- CN
- China
- Prior art keywords
- conductor
- line
- ground electrode
- matching
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P5/00—Coupling devices of the waveguide type
- H01P5/02—Coupling devices of the waveguide type with invariable factor of coupling
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P5/00—Coupling devices of the waveguide type
- H01P5/08—Coupling devices of the waveguide type for linking dissimilar lines or devices
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P5/00—Coupling devices of the waveguide type
- H01P5/12—Coupling devices having more than two ports
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
Abstract
The utility model relates to a circuit board and an antenna module. A branch circuit for branching a high-frequency signal is formed on the circuit board (150). The circuit board (150) includes: a dielectric substrate (130); a ground electrode (GND) disposed on the dielectric substrate (130); and a line conductor (400) which is configured to be arranged on the dielectric substrate (105) opposite to the grounding electrode (GND) and is used for transmitting high-frequency signals. The line conductor (400) includes: a 1 st conductor (410A) to which a high-frequency signal is input; a 2 nd conductor (420A) and a 3 rd conductor (421A) which branch and output the high-frequency signal inputted to the 1 st conductor (410A); and a matching conductor (430) connected between the 1 st conductor (410A) and the 2 nd conductors (420A) and (421A). The line widths of the line conductor (400) before and after the branch point (CP) are equal. The effective dielectric constant between the matching conductor (430) and the ground electrode (GND) is different from the effective dielectric constant between the 1 st to 3 rd conductors and the ground electrode (GND).
Description
Technical Field
The present disclosure relates to a circuit board and an antenna module, and more particularly, to a technique for reducing loss of a circuit board including a branch circuit for high-frequency signals.
Background
In a communication device such as a smartphone, an array antenna having a plurality of antenna elements (radiation elements) is sometimes used. In such an array antenna, a branch circuit for distributing a high-frequency signal supplied from a power supply circuit to a plurality of antenna elements is used.
Japanese patent laid-open No. 2001-196849 (patent document 1) discloses an array antenna provided with a branch circuit for distributing a high-frequency signal from a power supply circuit. In the branch circuit disclosed in japanese patent application laid-open No. 2001-196849 (patent document 1), when the wavelength of a high-frequency signal to be transmitted is λ, impedance matching transmission lines for impedance matching having a line length of λ/4 are provided, so that impedance matching is performed between the input terminal and the output terminal of the branch circuit.
Documents of the prior art
Patent document
Patent document 1: japanese laid-open patent application No. 2001-196849
SUMMERY OF THE UTILITY MODEL
Problem to be solved by utility model
Generally, the impedance of a transmission line for impedance matching of a branch circuit is different from the impedance at the input terminal and the output terminal of the branch circuit. In the branch circuit disclosed in japanese patent laid-open No. 2001-196849 (patent document 1), the impedance of the transmission line for impedance matching is adjusted by changing the line width of the transmission line.
However, if there is a portion of the line conductor (transmission line) of the branch circuit having a different line width, reflection of a signal may occur in the portion, and reflection loss may increase.
The present disclosure has been made to solve the above-described problems, and an object thereof is to perform impedance matching and reduce loss in a circuit board on which a branch circuit is formed.
Means for solving the problems
In the circuit board according to one aspect of the present disclosure, a branch circuit for branching a high-frequency signal is formed. The circuit board includes: a dielectric substrate; a ground electrode disposed on the dielectric substrate; and a line conductor configured to be disposed on the dielectric substrate so as to face the ground electrode and to transmit a high-frequency signal. The line conductor includes: a 1 st conductor to which a high-frequency signal is input; 2 nd and 3 rd conductors for branching and outputting the high frequency signal inputted to the 1 st conductor; and a matching conductor connected between the 1 st conductor and the 2 nd and 3 rd conductors. The line widths before and after the branch point of the line conductor are equal. The effective dielectric constant between the matching conductor and the ground electrode is different from the effective dielectric constant between the 1 st to 3 rd conductors and the ground electrode.
Preferably, when the wavelength of the high-frequency signal is λ, the line length of the matching conductor is set to λ/4.
Preferably, the matching conductor is connected between the 1 st conductor and a branch point of the line conductor, and an effective permittivity between the matching conductor and the ground electrode is larger than an effective permittivity between the 1 st to 3 rd conductors and the ground electrode.
Preferably, in the dielectric substrate, a space is formed between the 1 st to 3 rd conductors and the ground electrode.
Preferably, in the dielectric substrate, a dielectric having a dielectric constant lower than that of the dielectric between the matching conductor and the ground electrode is disposed between the 1 st to 3 rd conductors and the ground electrode.
Preferably, in the dielectric substrate, a dielectric having a dielectric constant higher than that of the dielectric between the 1 st to 3 rd conductors and the ground electrode is disposed between the matching conductor and the ground electrode.
Preferably, the matching conductor is connected between a branch point of the line conductor and the 2 nd conductor and the 3 rd conductor, and an effective permittivity between the matching conductor and the ground electrode is smaller than an effective permittivity between the 1 st conductor to the 3 rd conductor and the ground electrode.
Preferably, in the dielectric substrate, a space is formed between the matching conductor and the ground electrode.
Preferably, in the dielectric substrate, a dielectric having a dielectric constant lower than that of the dielectric between the 1 st to 3 rd conductors and the ground electrode is disposed between the matching conductor and the ground electrode.
Preferably, in the dielectric substrate, a dielectric having a dielectric constant higher than that of the dielectric between the matching conductor and the ground electrode is disposed between the 1 st to 3 rd conductors and the ground electrode.
Preferably, the line length of the 2 nd conductor is equal to the line length of the 3 rd conductor, the line width of the 2 nd conductor is equal to the line width of the 3 rd conductor, and the effective permittivity between the 2 nd conductor and the ground electrode is equal to the effective permittivity between the 3 rd conductor and the ground electrode.
Preferably, the line length of the 2 nd conductor is greater than the line length of the 3 rd conductor, the 2 nd conductor includes a 1 st portion having a line width greater than the line width of the 3 rd conductor, and an effective permittivity between the 1 st portion and the ground electrode is smaller than an effective permittivity between the 3 rd conductor and the ground electrode.
Preferably, the line length of the 2 nd conductor is greater than the line length of the 3 rd conductor, the 3 rd conductor includes a 2 nd portion having a line width smaller than the line width of the 2 nd conductor, and an effective permittivity between the 2 nd portion and the ground electrode is greater than an effective permittivity between the 2 nd conductor and the ground electrode.
In an antenna module of an aspect of the present disclosure, the antenna module includes: a plurality of radiating elements; and the circuit substrate.
Preferably, the antenna module further includes a power supply circuit that supplies the high-frequency signal to the plurality of radiation elements via the circuit substrate.
In a circuit board according to an aspect of the present disclosure, a branch circuit for branching a high-frequency signal is formed on the circuit board, and the circuit board includes: a dielectric substrate; a ground electrode disposed on the dielectric substrate; and a line conductor configured to be disposed on the dielectric substrate so as to face the ground electrode and to transmit the high-frequency signal, the line conductor including: a 1 st conductor to which the high-frequency signal is input; and a 2 nd conductor and a 3 rd conductor which branch off and output the high-frequency signal input to the 1 st conductor, wherein line widths before and after a branch point of the line conductor are equal, and a space is formed between a portion from the branch point to the 2 nd conductor and the ground electrode and between a portion from the branch point to the 3 rd conductor and the ground electrode in the line conductor when the circuit board is viewed in a plan view.
Effect of the utility model
According to the present disclosure, in the circuit board on which the branch circuit is formed, the effective dielectric constant between the matching conductor for impedance matching and the ground electrode is made different from the effective dielectric constant between the input conductor (1 st conductor) and the ground electrode and between the output conductor (2 nd conductor, 3 rd conductor) after branching, so that the line widths of the line conductors before and after the branching point can be made equal while impedance matching. This can suppress reflection loss due to a change in the line width, and thus can reduce the loss of the entire circuit board. Therefore, in the circuit board on which the branch circuit is formed, the impedance before and after the branch point can be matched and the loss can be reduced.
Drawings
Fig. 1 is a block diagram of a communication device in which an antenna module to which a circuit board according to embodiment 1 is applied is mounted.
Fig. 2 is a partial cross-sectional view of the circuit board of embodiment 1.
Fig. 3 is a diagram for explaining a two-branch type branch circuit according to embodiment 1.
Fig. 4 is a diagram for explaining a three-branch type branch circuit according to embodiment 1.
Fig. 5 (a) and 5 (b) are views showing an example of a perspective view of a circuit board on which a bifurcate branch circuit is formed.
Fig. 6 is a diagram for explaining a comparison between the insertion loss of the circuit board according to embodiment 1 and the insertion loss of the comparative example.
Fig. 7 (a), 7 (b), and 7 (c) are diagrams illustrating example 1 of the branch circuit for adjusting the phase of the output signal.
Fig. 8 (a), 8 (b), and 8 (c) are diagrams illustrating example 2 of the branch circuit for adjusting the phase of the output signal.
Fig. 9 is a partial cross-sectional view of the circuit board according to embodiment 2.
Fig. 10 is a diagram for explaining a two-branch type branch circuit according to embodiment 2.
Fig. 11 is a diagram for explaining a three-branch type branch circuit according to embodiment 2.
Fig. 12 (a) and 12 (b) are views showing an example of a perspective view of a circuit board on which a bifurcate branch circuit is formed in embodiment 2.
Fig. 13 (a), 13 (b), and 13 (c) are diagrams for explaining example 1 of the branch circuit in which the phase of the output signal is adjusted.
Fig. 14 (a), 14 (b), and 14 (c) are diagrams illustrating example 2 of the branch circuit for adjusting the phase of the output signal.
Detailed Description
Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the drawings, the same or corresponding portions are denoted by the same reference numerals, and description thereof will not be repeated.
[ embodiment 1]
(basic Structure of communication device)
Fig. 1 is an example of a block diagram of a communication device 10 on which an antenna module 100 to which the circuit board of embodiment 1 is applied is mounted. The communication device 10 is, for example, a mobile terminal such as a mobile phone, a smart phone, or a tablet computer, a personal computer having a communication function, or the like. Examples of the frequency band of the radio wave used in the antenna module 100 of the present embodiment are radio waves in the millimeter wave band having a center frequency of 28GHz, 39GHz, 60GHz, and the like, for example, but radio waves in other frequency bands than the above can be applied.
Referring to fig. 1, a communication apparatus 10 includes an antenna module 100 and a BBIC 200 constituting a baseband signal processing circuit. The antenna module 100 includes an RFIC 110 and an antenna device 120 as an example of a power supply circuit. The communication device 10 up-converts a signal passed from the BBIC 200 to the antenna module 100 into a high-frequency signal and radiates from the antenna device 120, and down-converts a high-frequency signal received by the antenna device 120 and processes the signal with the BBIC 200.
The antenna device 120 is an array antenna in which a plurality of antenna elements 121 are arranged in an array. Fig. 1 shows an example in which 16 antenna elements 121 are two-dimensionally arranged in a 4 × 4 array. The antenna device 120 may be a one-dimensional array in which a plurality of antenna elements 121 are arranged in a row. In the present embodiment, an example will be described in which the antenna element 121 is a patch antenna having a substantially square plate shape, but the antenna element 121 may be a linear antenna such as a monopole antenna or a dipole antenna, a slot antenna, or the like.
When transmitting a high-frequency signal, switches 111A to 111D and 113A to 113D are switched to the power amplifiers 112AT to 112DT side, and switch 117 is connected to the transmission-side amplifier of amplifier circuit 119. When receiving a high frequency signal, switches 111A to 111D and 113A to 113D are switched to low noise amplifiers 112AR to 112DR, and switch 117 is connected to a receiving-side amplifier of amplifier circuit 119.
The signal delivered from the BBIC 200 is amplified by an amplifying circuit 119 and up-converted by a mixer 118. A transmission signal, which is a high-frequency signal obtained by up-conversion, is divided into 4 signals by the signal combiner/splitter 116, and the signals are supplied to the antenna element 121 through 4 signal paths. In this case, the directivity of the antenna device 120 can be adjusted by adjusting the phase shift degree of each of the phase shifters 115A to 115D disposed in each signal path.
The received signals, which are high-frequency signals received by the respective antenna elements 121, are multiplexed by the signal multiplexer/demultiplexer 116 via 4 different signal paths. The combined received signal is down-converted by the mixer 118, amplified by the amplifier 119, and transferred to the BBIC 200.
The RFIC 110 is formed as a single-chip integrated circuit component including the above circuit configuration, for example. Alternatively, the RFIC 110 may be formed as a single-chip integrated circuit component for each of the corresponding antenna elements 121, with respect to the devices (switches, power amplifiers, low noise amplifiers, attenuators, and phase shifters) corresponding to the respective antenna elements 121.
In the antenna device 120 according to embodiment 1, 4 antenna elements 121 arranged in a row are grouped into 1 group (hereinafter, also referred to as "antenna group"), and the antenna elements 121 of the same antenna group are supplied with a common high-frequency signal by the RFIC 110. For example, in the antenna device 120 of fig. 1, a high-frequency signal via the switch 111A is supplied to the antenna group on the uppermost layer (layer 1) via the circuit board 150A on which the branch circuit is formed. Similarly, the high-frequency signal via the switch 111B is supplied to the antenna group of the layer 2 via the circuit board 150B. The high-frequency signal via the switch 111C is supplied to the antenna group of the 3 rd layer via the circuit board 150C, and the high-frequency signal via the switch 111D is supplied to the antenna group of the lowermost layer (the 4 th layer) via the circuit board 150D. In the following description, the circuit boards 150A to 150D on which these branch circuits are formed are also collectively referred to as "circuit board 150".
(description of the Branch Circuit)
In a device for transmitting a high-frequency signal, generally, the input impedance or the output impedance of each circuit connected to a signal transmission path is brought close to the impedance of a transmission line connected to an input terminal or an output terminal of each circuit, thereby suppressing loss caused by impedance mismatch. The impedance of the transmission line is, for example, 50 Ω, which is also referred to as "characteristic impedance".
In a branch circuit that distributes the signal from the RFIC 110 to the plurality of antenna elements 121 as described above, it is necessary to match the impedance at the input terminal or the output terminal after branching of the branch circuit in order to reduce the loss.
When a branch circuit is formed by a strip line or a microstrip line in which a line conductor is formed in a substrate, a plurality of output conductors are connected in parallel to an input conductor before and after a branch point of the line conductor. Therefore, simply connecting a plurality of output conductors to the input conductor makes the impedance of the branch point when viewed from the input conductor smaller than the desired characteristic impedance. In order to eliminate this impedance mismatch, a matching circuit for matching impedances before and after the branch point is usually formed at a position closer to the input conductor than the branch point or closer to the output conductor than the branch point in the branch circuit.
As such a matching circuit, a matching circuit formed of a line conductor having a line length of λ/4 is known, assuming that λ is a wavelength in a substrate of a high-frequency signal to be transmitted. When the impedances of two lines connected to the matching circuit are respectively set to Za、ZcThen the impedance Z of the matching circuitbThe expression can be generally expressed by the following formula (1).
In the case of forming a branch circuit using a line conductor, if the line conductor has the same thickness and the same line length, the impedance of the line conductor is basically determined by the line width. Therefore, in the branch circuit, when a matching circuit is provided for impedance matching before and after the branch point, the line width discontinuously changes at the connection portion between the input conductor or the output conductor and the matching circuit. In this way, signal reflection occurs due to the difference in the line width, and as a result, reflection loss may increase.
In embodiment 1, in a circuit board in which a branch circuit is formed by a strip line or a microstrip line, a space is formed between an input conductor and/or an output conductor before and after a matching circuit and a ground electrode or between a matching circuit and a ground electrode in a dielectric layer to reduce an effective dielectric constant, so that the input conductor and the output conductor have the same line width as the matching circuit. With such a configuration, in the circuit board on which the branch circuit is formed, it is possible to match the impedance and reduce the loss due to reflection.
The detailed configuration of the circuit board according to embodiment 1 will be described below. Fig. 2 is a partial cross-sectional view of the circuit board of embodiment 1.
Referring to fig. 2, the circuit substrate 150 includes an electric substrate 130, a ground electrode GND, and a line conductor 160 for forming a branch circuit. In the example of fig. 2, the circuit board 150 is formed as a strip line. That is, the ground electrodes GND are disposed so as to face the front layer and the back layer of the dielectric substrate 130, and the line conductor 160 is disposed between the two ground electrodes GND.
Here, it is known that the effective dielectric constant between the line conductor 160 and the ground electrode GND is ∈rThe impedance Z of the line conductor 160 is equal to the effective dielectric constant ε as shown in the following formula (2)rThe square root of (a) is inversely proportional.
Thus, if the space 170 is formed between the line conductor 160 and the ground electrode GND to reduce the effective dielectric constant, the impedance of the line conductor 160 of that portion increases. Further, the impedance increased by enlarging the line width of the line conductor 160 can be reduced to match the impedance in the case where the space 170 is not provided. In this way, by forming a space of an appropriate size in a portion of the dielectric substrate corresponding to the line conductor having a relatively narrow line width, the line width of the entire line conductor can be made to correspond to the portion having a relatively wide line width.
Fig. 3 is a diagram for explaining a two-branch type branch circuit that outputs a high-frequency signal received at an input terminal to two output terminals. Fig. 4 is a diagram for explaining a three-branch type branch circuit that outputs a high-frequency signal to 3 output terminals.
In fig. 3 and 4, a comparative example in which branch circuits are formed on a substrate having a uniform effective dielectric constant is shown in the left column, and the branch circuit of embodiment 1 is shown in the right column. In fig. 3 and 4, the upper part shows a case where a matching circuit is formed on the input conductor side (trunk side) of the branch point CP, and the lower part shows a case where a matching circuit is formed on the output conductor side (branch side) of the branch point CP.
< two-branch case >
First, a case where a matching circuit is formed on the dry side in the upper part will be described with reference to fig. 3. The line conductor 300 forming the branch circuit IN the comparative example includes an input conductor (1 st conductor) 310 having an input terminal IN, an output conductor (2 nd conductor) 320 having an output terminal OUT1, an output conductor (3 rd conductor) 321 having an output terminal OUT2, and a matching conductor 330 functioning as a matching circuit. The matching conductor 330 has a line length of λ/4 and is connected between the input conductor 310 and a branch point CP at which the output conductor 320 and the output conductor 321 are connected.
Z represents the impedance of the input conductor 310 and the two output conductors 320 and 3210When the characteristic impedance of (1) is reached, the impedance at the branch point CP becomes Z0And/2, therefore, according to the above equation (1), the impedance of the matching conductor 330 becomes
That is, the impedance Z of the matching conductor 330 is required1Less than the characteristic impedance (Z) of the input conductor 310 and the output conductors 320, 3211＜Z0) Therefore, as a result, it is necessary to set the line width of the matching conductor 330 to √ 2 times the line width of the input conductor 310 and the output conductors 320 and 321. In this case, a step difference is generated in line width at the connection portion of the input conductor 310 and the matching conductor 330, and reflection loss may be generated at the step difference.
On the other hand, in the line conductor 400 forming the branch circuit according to embodiment 1, the dielectric substrate 130 between the input conductor 410A and the ground electrode GND and between the output conductors 420A and 421A and the ground electrode GND forms a space 450 and a space 451, respectively, in the circuit substrate 150. Due to this space, the effective dielectric constant between the input conductor 410A and the output conductors 420A, 421A and the ground electrode GND decreases, and the impedance of the input conductor 410A and the output conductors 420A, 421A increases. Accordingly, the line widths of the input conductor 410A and the output conductors 420A and 421A are increased to match the impedance of the input conductor 410A and the output conductors 420A and 421A with the characteristic impedance. With such a configuration, a step in the line width generated at the connection portion between input conductor 410A and matching conductor 430 can be eliminated, and therefore, the reflection loss generated by the step can be reduced.
Next, a case where a matching circuit is formed on the branch side in the lower part of fig. 3 will be described. The line conductor 301 forming the branch circuit in the comparative example includes an input conductor 310, output conductors 320 and 321, and a matching conductor 335 functioning as a matching circuit. The matching conductor 335 has a line length of λ/4 and is connected between the branch point CP and the output conductor 320 and between the branch point CP and the output conductor 321.
In the line conductor 301, the impedance Z with respect to the branch point CP0/2, the impedance of each output terminal OUT1, OUT2 is Z0Therefore, according to the above equation (1), the impedance of the matching conductor 335 becomes
Impedance Z of matching conductor 3351Greater than the impedance Z of the output conductors 320, 3210(Z1＞Z0) And thus the line width of the matching conductor 335 is smaller than the respective line widths of the output conductors 320, 321. Therefore, a step difference in line width is generated between the matching conductor 335 and the output conductors 320 and 321, and reflection loss is generated.
In contrast, in the line conductor 401 forming the branch circuit according to embodiment 1, a space 453 is formed between the matching conductor 435 and the ground electrode GND. In other words, in the line conductor 401, spaces are formed between the ground electrode GND and the portion from the branch point CP to the output conductor 420 and between the ground electrode GND and the portion from the branch point CP to the output conductor 421. In response to this, the matching conductor 435 has the same line width as the input conductor 410 and the output conductors 420 and 421. This eliminates a step in the line width between the matching conductor 435 and the output conductors 420 and 421, and reduces the reflection loss caused by the step.
< three-branched case >
Next, an example of the case of the three-branch type branch circuit will be described with reference to fig. 4. First, a case where a matching circuit is formed on the dry side in the upper part of fig. 4 will be described. The line conductor 500 forming the branch circuit IN the comparative example includes an input conductor 510 having an input terminal IN, an output conductor 520 having an output terminal OUT1, an output conductor 521 having an output terminal OUT2, an output conductor 522 having an output terminal OUT3, and a matching conductor 530 functioning as a matching circuit. The matching conductor 530 has a line length of λ/4 and is connected between the input conductor 510 and a branch point CP to which the output conductors 520 to 522 are connected.
Z represents the impedance of the input conductor 510 and the 3 output conductors 520-5220When the characteristic impedance of (1) is reached, the impedance at the branch point CP becomes Z0And/3, therefore, the impedance of the matching conductor 530 becomes according to the above equation (1)
Therefore, it is necessary to set the line width of the matching conductor 330 to the line width of the input conductor 510 and the output conductors 520 to 522
And (4) doubling. In this case, a step difference where reflection loss is generated occurs in the line width at the connection portion of the input conductor 510 and the matching conductor 530.
In the line conductor 600 forming a branch circuit according to embodiment 1, the dielectric substrate 130 between the input conductor 610A and the ground electrode GND and between the output conductors 620A to 622A and the ground electrode GND forms a space 650 and a space 651, respectively, in the circuit board 150. This reduces the effective dielectric constant between the input conductor 610A and the output conductors 620A to 622A and the ground electrode GND, and increases the impedance of the input conductor 610A and the output conductors 620A to 622A. Accordingly, the line widths of the input conductor 610A and the output conductors 620A to 622A are increased so that the impedances of the input conductor 610A and the output conductors 620A to 622A match the characteristic impedance. With such a configuration, a step in the line width generated at the connection portion between the input conductor 610A and the matching conductor 630 can be eliminated, and therefore, the reflection loss generated by the step can be reduced.
Next, a case where a matching circuit is formed on the branch side in the lower part of fig. 4 will be described. In the comparative example, the line conductor 501 forming the branch circuit includes an input conductor 510, output conductors 520 to 522, and a matching conductor 535 functioning as a matching circuit. The matching conductor 535 has a line length of λ/4 and is connected between the branch point CP and the output conductor 520, between the branch point CP and the output conductor 521, and between the branch point CP and the output conductor 522.
In the line conductor 501, the impedance Z with respect to the branch point CP0(iii) each of the output terminals OUT 1-OUT 3 has an impedance Z0Therefore, according to the above equation (1), the impedance of the matching conductor 535 becomes
Impedance Z of matching conductor 5351Impedance Z larger than output conductors 520-5220(Z1＞ Z0) Therefore, the line width of the matching conductor 535 is smaller than the line widths of the output conductors 520 to 522. Therefore, a step difference in line width is generated between the matching conductor 535 and the output conductors 520 to 522, and reflection loss is generated.
In contrast, in the line conductor 601 forming the branch circuit according to embodiment 1, a space 652 is formed between the matching conductor 635A and the ground electrode GND, and the line width of the matching conductor 635A is set to be the same as the line width of the input conductor 610 and the output conductors 620 to 622. This eliminates the step in the line width at the connection between matching conductor 635A and output conductors 620 to 622, and reduces the reflection loss due to the step.
Fig. 5 is a diagram showing an example of a perspective view of a circuit board in which a two-branch type branch circuit having a matching conductor is formed on the trunk side shown in the upper part of fig. 3. Fig. 5 (a) shows a circuit board 150# on which a line conductor 300 of a comparative example is formed, and fig. 5 (b) shows a circuit board 150 on which a line conductor 400 of embodiment 1 is formed. In fig. 5, the ground electrode GND and the dielectric substrate 130 on the front surface side are drawn in a perspective view for ease of explanation.
Referring to fig. 5 (a), the branch circuit is formed of a line conductor 300 disposed in a layer inside the dielectric substrate 130 as shown in fig. 3. The line conductor 300 has a substantially T-shape. The input terminal IN of the input conductor 310 functions as an input port to which an external transmission line is connected. A matching conductor 330 is connected to the other end of the input conductor 310. Output conductors 320 and 321 are connected to the other end of matching conductor 330 (i.e., branch point CP).
Further, a plurality of via holes 180 are formed around the line conductor 300 along each conductor of the line conductor 300. The via hole 180 is connected to the ground electrodes GND formed on the upper and lower surfaces of the circuit board 150 #. The plurality of via holes 180 function as shielding walls for suppressing electromagnetic coupling with other wiring patterns (not shown) inside the dielectric substrate 130.
As shown in fig. 5 (a), in the circuit board 150# of the comparative example, the dielectric constant of the dielectric substrate 130 is substantially uniform, and the line width of the matching conductor 330 is larger than the line widths of the input conductor 310 and the output conductors 320 and 321.
On the other hand, in the circuit board 150 of embodiment 1 shown in fig. 5b, spaces 450 and 451 (the dotted line portion in fig. 5 b) are formed between the ground electrode GND and the portion of the line conductor 400 other than the matching conductor 430. The line widths of the input conductor 410A and the output conductors 420A and 421A corresponding to the input conductor 310 and the output conductors 320 and 321 are set to be the same as those of the matching conductor 430.
Fig. 6 is a diagram for comparing insertion loss with respect to a circuit board on which the two-branch type branch circuit shown in fig. 5 is formed. In fig. 6, the horizontal axis represents frequency and the vertical axis represents insertion loss. In fig. 6, a solid line LN10 indicates the insertion loss in the case of the circuit board 150 according to embodiment 1, and a broken line LN11 indicates the insertion loss in the case of the circuit board 150# according to the comparative example.
As shown in fig. 6, it is understood that the insertion loss of the circuit board 150 of embodiment 1 is improved over the entire frequency region as compared with the case of the circuit board 150# of the comparative example. In other words, a bandwidth expansion of a predetermined insertion loss can be achieved.
As described above, in the circuit board on which the branch circuit for branching a high-frequency signal is formed, the effective permittivity is reduced by forming a space in the dielectric substrate between the ground electrode and the portion of the line conductor forming the branch circuit where the line width is relatively narrow, and the line width of the portion forming the space is increased, and the same line width is set over the entire line conductor. This prevents reflection of a high-frequency signal due to a step in the line width, and thus impedance matching can be performed and loss can be reduced.
In the case of branching a common high-frequency signal to 4 antenna elements as shown in fig. 1, a configuration may be adopted in which a bifurcate branch circuit is further formed at each output terminal of the bifurcate branch circuit described above, or a configuration may be adopted in which a bifurcate branch circuit is formed at any one of the output terminals of the bifurcate branch circuit described above. Alternatively, although not shown, a high-frequency signal may be branched from one input conductor to 4 output conductors.
In addition, in embodiment 1 described above, an example in which the effective dielectric constant is reduced by forming a space in the dielectric layer has been described, but a dielectric having a dielectric constant lower than that of the other dielectric may be disposed in the portion where the space is formed.
(modification: phase adjustment of output Signal)
In the circuit board according to embodiment 1 described above, the description has been made on the assumption that the line lengths of the output conductors from the branch point of the branch circuit to the respective output terminals are the same.
However, when the circuit board is mounted on an actual device, the line lengths of the output conductors may need to be set to different lengths. In the above example, since the portions of the output conductors are set to have the same effective dielectric constant, the wavelengths of the high-frequency signals transmitted through the output conductors are substantially the same. In this case, if the line lengths (physical lengths) of the output conductors are different, the wave numbers of the high-frequency signals transmitted through the output conductors are different, and therefore the phases of the high-frequency signals at the output ends are different. Thus, the directivity and efficiency of the array antenna as a whole may be deteriorated.
Thus, in the modification, the following configuration is adopted: for an output conductor having a relatively long line length, a space is newly formed between the ground electrode and the output conductor, or the height of the formed space is made higher than the height of the other space portion, thereby further reducing the effective dielectric constant of the portion of the output conductor. This makes it possible to increase the wavelength of the high-frequency signal transmitted through the output conductor having a relatively long line length. Therefore, even when the line lengths of the output conductors are different, the phases of the high-frequency signals at the output ends can be made uniform by appropriately adjusting the effective dielectric constants for the respective output conductors.
Fig. 7 and 8 are diagrams illustrating example 1 and example 2 of a branch circuit for adjusting the phase of an output signal, respectively. The circuit boards shown in fig. 7 and 8 correspond to a configuration in which, in the circuit board on which the three-branch type branch circuit described in fig. 4 is formed, the line length D2 of the output conductor that transmits a high-frequency signal to the output terminals OUT1, OUT2 is longer than the line length D1 of the output conductor that transmits a high-frequency signal to the output terminal OUT3 (D2 > D1). Fig. 7 shows an example of a case where a matching conductor is formed on the trunk side, and fig. 8 shows an example of a case where a matching conductor is formed on the branch side.
Referring to fig. 7, (a) of fig. 7 shows a comparative example in which the effective dielectric constant of the dielectric substrate is uniform. In the line conductor 500A of this comparative example, the line width of the matching conductor 530 is larger than the line widths of the input conductor 510 and the output conductors 522, 525, 526. In addition, in the case of fig. 7 (a), since the effective dielectric constant is uniform and the wavelengths of the high-frequency signals transmitted in the output conductors are the same, the phases of the high-frequency signals at the output terminals OUT1, OUT2 of the output conductors 525, 526 having a relatively long line length are different from the phase of the high-frequency signal at the output terminal OUT3 of the output conductor 522 having a relatively short line length.
In the line conductor 600A of fig. 7 (b), as described in embodiment 1 above, the line widths of the input conductor 610A and the output conductors 622A, 625A, and 626A are set to the same line width as the matching conductor 630 by forming the spaces 650 and 651 between the input conductor 610A and the output conductors 622A, 625A, and 626A and the ground electrode GND. However, in the line conductor 600A, since the effective dielectric constants of the respective output conductors are the same, although the reflection loss due to the step difference in line width can be reduced, the phases of the high-frequency signals at the output terminals OUT1, OUT2 are still different from the phase of the high-frequency signal at the output terminal OUT 3.
In the line conductor 600B of the modification shown in fig. 7 (c), the dimensions in the height direction of the spaces 655 and 656 formed corresponding to the output conductors 625B and 626B having relatively long line lengths are higher than the dimensions in the height direction of the spaces 650A and 651A formed corresponding to the input conductor 610A and the output conductor 627A. Thus, the effective permittivity for output conductors 625B, 626B is further less than the effective permittivity for output conductor 627A, and thus the wavelength of the high frequency signal propagating in output conductors 625B, 626B is greater than the wavelength of the high frequency signal propagating in output conductor 627A. Thus, by appropriately setting the dimensions of the spaces 650A, 651A in the height direction, the phases of the high-frequency signals at the output terminals OUT1, OUT2 can be made to coincide with the phase of the high-frequency signal at the output terminal OUT 3. In addition, since the phases of the high-frequency signals can be made uniform even if the lengths of the output conductors are different, and the lengths of the output conductors do not need to be made uniform for phase adjustment, it is possible to prevent unnecessary wiring patterns from being arranged in the circuit board, and to contribute to downsizing of the circuit board.
Further, in the line conductor 600B of fig. 7 (c), since the effective dielectric constant with respect to the output conductors 625B, 626B is small, the impedance at the output terminals OUT1, OUT2 is larger than the characteristic impedance Z0. Therefore, in order to set the impedances at the output terminals OUT1, OUT2 to the characteristic impedance Z0The impedance needs to be reduced by making the line width of the output conductors 625B and 626B further larger than the line width of the other line conductors. If the line width is changed to reduce the impedance, a step is generated in the line width at the connection portion with the output conductors 625B, 626B, and some reflection loss is generated at this portion. However, since the input conductor 610A and the matching conductor 63 are connectedThe line widths at the connection portion of 0 and before and after the branch point CP are set to the same line width, and therefore the reflection loss is reduced as compared with the line conductor 500A of the comparative example.
Next, a case where a high dielectric constant layer is formed on the branch side will be described. Referring to fig. 8, (a) of fig. 8 is a comparative example in which the effective dielectric constant of the dielectric substrate is uniform, and in the line conductor 501A of this comparative example, the line width of the matching conductor 535 formed on the branch side is smaller than the line widths of the input conductor 510 and the output conductors 522, 525, 526. Also in this comparative example, the phases of the high-frequency signals at the output terminals OUT1, OUT2 are different from the phase of the high-frequency signal at the output terminal OUT 3.
In the line conductor 601A in fig. 8 (b), the space 652 is formed between the matching conductor 635A including the branch point CP and the ground electrode GND, whereby the line width of the matching conductor 635A is set to be the same as the line width of the input conductor 610 and the output conductors 622, 625, and 626. However, in the line conductor 601A, although the reflection loss due to the step difference in line width can be reduced, the phases of the high-frequency signals at the output terminals OUT1, OUT2 and the phase of the high-frequency signal at the output terminal OUT3 are still different.
In the line conductor 601B of the modification shown in fig. 8 (C), a space 657 is formed between the output conductors 625C and 626C and the ground electrode GND. In fig. 8 (c), space 657 also includes a portion of space 652 formed corresponding to matching conductor 635A in fig. 8 (b). In addition, the line width of the output conductors 625C and 626C is enlarged correspondingly.
Since the effective permittivity of the output conductors 625C and 626C can be reduced by the structure in which the space 657 is formed, the wavelength of the high-frequency signal transmitted through the output conductors 625C and 626C is longer than the wavelength of the high-frequency signal transmitted through the output conductor 627. Thereby, the phases of the high-frequency signals at the output terminals OUT1, OUT2 can be made to coincide with the phase of the high-frequency signal at the output terminal OUT 3.
In fig. 7 and 8, the case of the three-branch type branch circuit is described, but in the two-branch type branch circuit, the phase at the output end can be adjusted by applying the configuration of the above-described modification even when the lengths of the two output conductors are different.
[ embodiment 2]
Fig. 9 is a partial cross-sectional view of the circuit board 151 of embodiment 2. Referring to fig. 9, the circuit board 151 includes a dielectric substrate 130, a ground electrode GND, and a line conductor 160 for forming a branch circuit. The circuit board 151 is formed as a strip line, similarly to the circuit board 150 of embodiment 1.
In the circuit board 151 of fig. 9, a high dielectric constant layer 175 having a dielectric constant higher than that of the dielectric substrate 130 is formed between the ground electrode GND and a portion of the line conductor 160 having a relatively wide line width. With this high dielectric constant layer 175, the effective dielectric constant of a portion where the line width is relatively wide is increased, and therefore the impedance of this portion is reduced according to the above-described equation (2). The line width of the line conductor 160 in this portion is narrowed, so that the impedance is made equal to the impedance of the line conductor 160 in the other portion. In this way, by forming the high dielectric constant layer in the portion of the dielectric substrate corresponding to the line conductor having a relatively wide line width, the line width of the entire line conductor can be made to correspond to the portion having a relatively narrow line width. This can reduce reflection loss due to a step difference in line width.
Next, a two-branch type branch circuit and a three-branch type branch circuit will be described in the same manner as in embodiment 1, with reference to fig. 10 and 11.
Fig. 10 and 11 also show a comparative example in which branch circuits are formed on a substrate having a uniform effective dielectric constant in the left column, and the branch circuits of embodiment 2 in the right column. In fig. 10 and 11, the upper part shows a case where a matching circuit is formed on the trunk side, and the lower part shows a case where a matching circuit is formed on the branch side.
The comparative example in fig. 10 and 11 is the same as the comparative example in fig. 3 and 4, and therefore detailed description thereof will not be repeated.
< two-branch case >
Referring to fig. 10, first, a case where a matching circuit is formed on the dry side in the upper part of fig. 10 will be described. In the line conductor 700 forming the branch circuit of embodiment 2, the high dielectric constant layer 750 is formed between the ground electrode GND and the matching conductor 730A corresponding to the matching conductor 330 having a relatively wide line width in the comparative example. Thereby, the effective dielectric constant between the matching conductor 730A and the ground electrode GND increases, and the impedance of the matching conductor 730A decreases. Accordingly, the impedance of the matching conductor 730A is made to match that of the comparative example by narrowing the line width of the matching conductor 730A. With such a configuration, a step in the line width generated at the connection portion between the input conductor 710 and the matching conductor 730A can be eliminated, and therefore, the reflection loss generated by the step can be reduced.
Next, a case where a matching circuit is formed on the branch side in the lower part of fig. 10 will be described. In the line conductor 701 forming the branch circuit according to embodiment 2, high dielectric constant layers 751 to 753 are formed between the input conductor 710A and output conductors 720A and 721A corresponding to the input conductor 310 and output conductors 320 and 321 having relatively wide line widths in the comparative example, and the ground electrode GND. This increases the effective dielectric constant between the input conductor 710A and the output conductors 720A and 721A and the ground electrode GND, and decreases the impedance of the input conductor 710A and the output conductors 720A and 721A. Accordingly, the line widths of the input conductor 710A and the output conductors 720A and 721A are narrowed, and the impedance of the input conductor 710A and the impedance of the output conductors 720A and 721A are made to match the characteristic impedance. This eliminates a step in the line width between the matching conductor 735 and the output conductors 720A and 721A, and reduces the reflection loss due to the step.
< three-branched case >
An example of the case of the three-branch type branch circuit is described with reference to fig. 11. In the case where a matching circuit is formed on the trunk side in the upper part of fig. 11, in the line conductor 800 forming a branch circuit of embodiment 2, as in the case of the two-branch type branch circuit of fig. 10, a high dielectric constant layer 850 is formed between the ground electrode GND and the matching conductor 830A corresponding to the matching conductor 530 having a relatively wide line width in the comparative example. Thereby, the effective dielectric constant between the matching conductor 830A and the ground electrode GND increases, and the impedance of the matching conductor 830A decreases. Accordingly, by narrowing the line width of the matching conductor 830A, the impedance of the matching conductor 830A is made to match the impedance in the case of the comparative example. With such a configuration, a step in the line width generated at the connection portion between the input conductor 810 and the matching conductor 830A can be eliminated, and therefore, the reflection loss generated by the step can be reduced.
Next, a case where a matching circuit is formed on the branch side in the lower part of fig. 11 will be described. In the line conductor 801 forming the branch circuit of embodiment 2, high dielectric constant layers 851 to 854 are formed between the input conductor 810A and the output conductors 820A to 822A corresponding to the input conductor 510 and the output conductors 520 to 522 having relatively wide line widths in the comparative example, and the ground electrode GND, respectively. This increases the effective dielectric constant between the input conductors 810A and 820A to 822A and the ground electrode GND, and decreases the impedance of the input conductors 810A and 820A to 822A. Accordingly, the line widths of the input conductor 810A and the output conductors 820A to 822A are narrowed to match the impedances of the input conductor 810A and the output conductors 820A to 822A with the characteristic impedance. This eliminates a step in the line width between the matching conductor 835 and the output conductors 820A to 822A, and reduces the reflection loss caused by the step.
Fig. 12 is a diagram showing an example of a perspective view of the circuit board 151 shown in the upper part of fig. 10, in which a two-branch type branch circuit having a matching conductor is formed on the trunk side. Fig. 12 (a) at the top shows a circuit board 151# on which a line conductor 300 of a comparative example is formed, and fig. 12 (b) at the bottom shows a circuit board 151 on which a line conductor 700 of embodiment 2 is formed. In fig. 12, the ground electrode GND and the dielectric substrate 130 on the front surface side are drawn in a perspective view for ease of explanation.
Referring to fig. 12 (a), the branch circuit is formed of a line conductor 300 disposed in a layer inside the dielectric substrate 130 as shown in fig. 10. The line conductor 300 has a substantially T-shape. The input terminal IN of the input conductor 310 functions as an input port to which an external transmission line is connected. A matching conductor 330 is connected to the other end of the input conductor 310. Output conductors 320 and 321 are connected to the other end of matching conductor 330 (i.e., branch point CP).
Further, a plurality of via holes 180 functioning as shield walls are formed around the line conductor 300 along each conductor of the line conductor 300.
As shown in fig. 12 (a), in the circuit board 151# of the comparative example, the dielectric constant of the dielectric substrate 130 is substantially uniform, and the line width of the matching conductor 330 is larger than the line widths of the input conductor 310 and the output conductors 320 and 321.
On the other hand, in the circuit board 151 of embodiment 2 shown in fig. 12 (b), the high dielectric constant layer 750 (the dashed line portion in fig. 12 (b)) is formed between the ground electrode GND and the portion of the matching conductor 730A of the line conductor 700. The matching conductor 730A corresponding to the matching conductor 330 has the same line width as the input conductor 710 and the output conductors 720 and 721.
(modification: phase adjustment of output Signal)
A configuration for adjusting the phase of an output signal when the lengths of output conductors are different in the circuit board according to embodiment 2 will be described with reference to fig. 13 and 14.
In the modification of embodiment 1, by forming a space or disposing a low dielectric constant layer in a dielectric substrate, the effective dielectric constant of an output conductor that is relatively long with respect to the line length is reduced and the wavelength of a high-frequency signal transmitted in the output conductor is made longer, thereby making the phases of the high-frequency signals at the output ends uniform.
As described in embodiment 2 above, if the effective dielectric constant of the line conductor increases, the wavelength of the high-frequency signal transmitted through the line conductor becomes shorter. Therefore, in the modification of embodiment 2, by newly arranging a high dielectric constant layer between the output conductor having a relatively short line length and the ground electrode, or by arranging a dielectric layer having a higher dielectric constant, the wavelength of the high-frequency signal transmitted through the output conductor is made shorter, and the phases of the high-frequency signals at the output terminals are made uniform.
Fig. 13 and 14 are diagrams for explaining example 1 and example 2 of the branch circuit for adjusting the phase of the output signal, respectively. The circuit boards shown in fig. 13 and 14 correspond to a configuration in which the circuit board on which the three-branch type branch circuit described in fig. 11 is formed has a configuration in which the line length D2 of the output conductor that transmits a high-frequency signal to the output terminals OUT1, OUT2 is longer than the line length D1 of the output conductor that transmits a high-frequency signal to the output terminal OUT3 (D2 > D1). Fig. 13 shows an example of the case where the matching conductor is formed on the main side, and fig. 14 shows an example of the case where the matching conductor is formed on the branch side.
Fig. 13 (a) and 14 (a) correspond to fig. 7 (a) and 8 (a) of the modification of embodiment 1, and show line conductors 500A and 501A of comparative examples in which the effective permittivity of the dielectric substrate is uniform. In the line conductors 500A, 501A, the phases of the high-frequency signals at the output terminals OUT1, OUT2 are different from the phase of the high-frequency signal at the output terminal OUT3 due to the difference in the line length of the output conductors.
In the line conductor 800A of fig. 13 (b), as described in embodiment 2, the high dielectric constant layer 850 is formed between the matching conductor 830A and the ground electrode GND, whereby the line width of the input conductor 810 and the line width of the matching conductor 830A are the same. However, in the line conductor 800A, since the effective dielectric constants are the same for the respective output conductors, although the reflection loss due to the step difference in line width can be reduced, the phases of the high-frequency signals at the output terminals OUT1, OUT2 are still different from the phase of the high-frequency signal at the output terminal OUT 3.
On the other hand, in the line conductor 800B of the modification shown in fig. 13 (c), the high dielectric constant layer 850A is newly formed between the output conductor 822A having a relatively short line length and the ground electrode GND. Thus, since the effective permittivity for output conductor 822A is greater than the effective permittivity for output conductors 825, 826, the wavelength of the high frequency signal propagating in output conductor 822A is less than the wavelength of the high frequency signal propagating in output conductors 825, 826. Thus, by appropriately setting the dielectric constant of the high dielectric constant layer, the phases of the high-frequency signals at the output terminals OUT1, OUT2 can be made to coincide with the phase of the high-frequency signal at the output terminal OUT 3.
Further, in the line conductor 800B of fig. 13 (c), since the effective dielectric constant with respect to the output conductor 822A is large, the impedance at the output terminal OUT3 is smaller than the characteristic impedance Z0. Therefore, in order to set the impedance at the output terminal OUT3 to the characteristic impedance Z0The line width of the output conductor 822A needs to be further smaller than those of the other line conductors to increase the impedance. When the line width is changed, a step difference occurs in the line width at the connection portion between the output conductor 822A and the branch point CP, and some reflection loss occurs in this portion, but since the line widths at the connection portion between the input conductor 810 and the matching conductor 830A and before and after the branch point CP are set to the same line width, the reflection loss is reduced as compared with the line conductor 500A of the comparative example.
Next, referring to fig. 14, in the line conductor 801A of fig. 14 (b), high dielectric constant layers 851 to 854 are formed between the line conductors (i.e., the input conductor 810A and the output conductors 822A, 825A, and 826A) other than the matching conductor 835 and the ground electrode GND, whereby the line widths of the input conductor 810A and the output conductors 822A, 825A, and 826A are set to the same line width as the matching conductor 835. However, in the line conductor 801A, although the reflection loss due to the step difference in line width can be reduced, the phases of the high-frequency signals at the output terminals OUT1, OUT2 and the phase of the high-frequency signal at the output terminal OUT3 are still different.
In the line conductor 801B of the modification shown in fig. 14 (c), a high dielectric constant layer 853A having a dielectric constant higher than that of the high dielectric constant layers 851, 852 formed between the output conductors 825A, 826A and the ground electrode GND is formed between the output conductor 822B and the ground electrode GND whose line length is relatively short. With such a configuration, the effective permittivity of the output conductor 822B is increased, and therefore the wavelength of the high-frequency signal transmitted through the output conductor 822B is smaller than the wavelength of the high-frequency signal transmitted through the output conductors 825A and 826A. Thereby, the phases of the high-frequency signals at the output terminals OUT1, OUT2 can be made to coincide with the phase of the high-frequency signal at the output terminal OUT 3.
In addition, although the case of the three-branch type branch circuit is described in fig. 13 and 14, the phase at the output end can be adjusted by applying the configuration of the above-described modification even in the case where the lengths of the two output conductors are different in the two-branch type branch circuit.
In the above description, the case where the line length of the matching conductor is λ/4 was described, but the line length of the matching conductor may be { (2n +1)/4} λ (n: natural number) such as 3 λ/4, 5 λ/4, or the like.
In the above description, the phrase "the line widths are the same" includes not only the case where the line widths are completely the same but also the case where the line widths are substantially the same. That is, it can be regarded as "substantially the same" if it is within a range of variation (for example, within ± 10%) in dimensional accuracy in manufacturing.
The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the embodiments described above, and is intended to include all modifications within the meaning and scope equivalent to the claims.
Description of the reference numerals
10. A communication device; 100. an antenna module; 110. an RFIC; 111A to 111D, 113A to 113D, 117, a switch; 112AR to 112DR, a low noise amplifier; 112 AT-112 DT, power amplifier; 114A to 114D, an attenuator; 115A to 115D, phase shifters; 116. a signal synthesizer/demultiplexer; 118. a mixer; 119. an amplifying circuit; 120. an antenna device; 121. an antenna element; 130. a dielectric substrate; 150. 150A-150D, 150#, 151#, and a circuit board; 160. 300, 301, 400, 401, 500A, 501A, 600A, 600B, 601A, 601B, 700, 701, 800A, 800B, 801A, 801B, a line conductor; 170. 450, 451, 453, 650A, 651A, 652, 655, 656, 657, space; 175. 750, 751, 753, 850A, 851-854, 853A, high dielectric constant layer; 180. a via hole; 200. BBIC; 310. 410, 410A, 510, 610A, 710A, 810A, an input conductor; 320. 321, 420A, 421A, 520, 521, 522, 525, 526, 620A, 622A, 625A, 625B, 625C, 626A, 626B, 626C, 627A, 720A, 721A, 820A, 822B, 825A, 826A, an output conductor; 330. 335, 430, 435, 530, 535, 630, 635A, 730A, 735, 830A, 835, matching conductor; CP, branch point; GND, ground electrode; IN, input end; OUT 1-OUT 3 and an output end.
Claims (16)
1. A circuit board on which a branch circuit for branching a high-frequency signal is formed,
the circuit substrate includes:
a dielectric substrate;
a ground electrode disposed on the dielectric substrate; and
a line conductor configured to be disposed on the dielectric substrate so as to face the ground electrode and to transmit the high-frequency signal,
the line conductor includes:
a 1 st conductor to which the high-frequency signal is input;
2 nd and 3 rd conductors which branch and output the high-frequency signal input to the 1 st conductor; and
a matching conductor connected between the 1 st conductor and the 2 nd and 3 rd conductors,
the line widths before and after the branch point of the line conductor are equal,
the effective dielectric constant between the matching conductor and the ground electrode is different from the effective dielectric constant between the 1 st to 3 rd conductors and the ground electrode.
2. The circuit substrate of claim 1,
when the wavelength of the high-frequency signal is λ, the line length of the matching conductor is λ/4.
3. The circuit substrate according to claim 1 or 2,
the matching conductor is connected between the branch point of the line conductor and the 1 st conductor,
an effective dielectric constant between the matching conductor and the ground electrode is larger than effective dielectric constants between the 1 st to 3 rd conductors and the ground electrode.
4. The circuit substrate according to claim 3,
in the dielectric substrate, a space is formed between the 1 st to 3 rd conductors and the ground electrode.
5. The circuit substrate according to claim 3,
in the dielectric substrate, a dielectric having a dielectric constant lower than that of the dielectric between the matching conductor and the ground electrode is disposed between the 1 st to 3 rd conductors and the ground electrode.
6. The circuit substrate according to claim 3,
in the dielectric substrate, a dielectric having a dielectric constant higher than that of the dielectric between the 1 st to 3 rd conductors and the ground electrode is disposed between the matching conductor and the ground electrode.
7. The circuit substrate according to claim 1 or 2,
the matching conductor is connected between a branch point of the line conductor and the 2 nd conductor and the 3 rd conductor,
an effective dielectric constant between the matching conductor and the ground electrode is smaller than an effective dielectric constant between the 1 st to 3 rd conductors and the ground electrode.
8. The circuit substrate of claim 7,
in the dielectric substrate, a space is formed between the matching conductor and the ground electrode.
9. The circuit substrate of claim 7,
in the dielectric substrate, a dielectric having a dielectric constant lower than that of the dielectric between the 1 st to 3 rd conductors and the ground electrode is disposed between the matching conductor and the ground electrode.
10. The circuit substrate of claim 7,
in the dielectric substrate, a dielectric having a dielectric constant higher than that of the dielectric between the matching conductor and the ground electrode is disposed between the 1 st to 3 rd conductors and the ground electrode.
11. The circuit substrate according to claim 1 or 2,
the line length of the 2 nd conductor is equal to the line length of the 3 rd conductor,
the line width of the 2 nd conductor is equal to the line width of the 3 rd conductor,
an effective permittivity between the 2 nd conductor and the ground electrode is equal to an effective permittivity between the 3 rd conductor and the ground electrode.
12. The circuit substrate according to claim 1 or 2,
the line length of the 2 nd conductor is greater than the line length of the 3 rd conductor,
the 2 nd conductor includes a 1 st portion having a line width greater than that of the 3 rd conductor,
an effective permittivity between the 1 st portion and the ground electrode is less than an effective permittivity between the 3 rd conductor and the ground electrode.
13. The circuit substrate according to claim 1 or 2,
the line length of the 2 nd conductor is greater than the line length of the 3 rd conductor,
the 3 rd conductor includes a 2 nd portion having a line width smaller than that of the 2 nd conductor,
an effective permittivity between the 2 nd portion and the ground electrode is greater than an effective permittivity between the 2 nd conductor and the ground electrode.
14. An antenna module, characterized in that,
the antenna module includes:
a plurality of radiating elements; and
the circuit substrate according to any one of claims 1 to 13.
15. The antenna module of claim 14,
the antenna module further includes a power supply circuit configured to supply the high-frequency signal to the plurality of radiating elements via the circuit substrate.
16. A circuit board on which a branch circuit for branching a high-frequency signal is formed,
the circuit substrate includes:
a dielectric substrate;
a ground electrode disposed on the dielectric substrate; and
a line conductor configured to be disposed on the dielectric substrate so as to face the ground electrode and to transmit the high-frequency signal,
the line conductor includes:
a 1 st conductor to which the high-frequency signal is input; and
a 2 nd conductor and a 3 rd conductor which branch and output the high frequency signal inputted to the 1 st conductor,
the line widths before and after the branch point of the line conductor are equal,
in a plan view of the circuit board, spaces are formed between the ground electrode and a portion of the line conductor from the branch point to the 2 nd conductor and between the ground electrode and a portion of the line conductor from the branch point to the 3 rd conductor.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2019-037266 | 2019-03-01 | ||
| JP2019037266 | 2019-03-01 | ||
| PCT/JP2020/006804 WO2020179476A1 (en) | 2019-03-01 | 2020-02-20 | Circuit board and antenna module |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216354707U true CN216354707U (en) | 2022-04-19 |
Family
ID=72338630
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202090000404.XU Active CN216354707U (en) | 2019-03-01 | 2020-02-20 | Circuit board and antenna module |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN216354707U (en) |
| WO (1) | WO2020179476A1 (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000307362A (en) * | 1999-04-23 | 2000-11-02 | Mitsubishi Electric Corp | Microwave amplifier circuit, dielectric substrate raw material and microwave amplifier circuit component |
| JP2001196849A (en) * | 2000-01-04 | 2001-07-19 | Sharp Corp | Power feeding circuit for array antenna |
| JP2008035336A (en) * | 2006-07-31 | 2008-02-14 | Toshiba Corp | High-frequency circuit device |
-
2020
- 2020-02-20 WO PCT/JP2020/006804 patent/WO2020179476A1/en active Application Filing
- 2020-02-20 CN CN202090000404.XU patent/CN216354707U/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| WO2020179476A1 (en) | 2020-09-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10950945B2 (en) | Antenna element, antenna module, and communication apparatus | |
| US7710338B2 (en) | Slot antenna apparatus eliminating unstable radiation due to grounding structure | |
| TWI449257B (en) | Antennas based on metamaterial structures | |
| US7701407B2 (en) | Wide-band slot antenna apparatus with stop band | |
| US20110026624A1 (en) | Metamaterial antenna array with radiation pattern shaping and beam switching | |
| CN109478721B (en) | Antenna, device with one or more antennas and communication device | |
| US7642981B2 (en) | Wide-band slot antenna apparatus with constant beam width | |
| CN111919338B (en) | Antenna module | |
| US11631936B2 (en) | Antenna device | |
| WO2020145392A1 (en) | Antenna module and communication device with same mounted thereon | |
| US10297928B2 (en) | Multi-port, multi-band, single connected multiple-input, multiple-output antenna | |
| CN114521307A (en) | Antenna module, communication device having the same mounted thereon, and circuit board | |
| US20220328978A1 (en) | Antenna module and communication device equipped with the same | |
| CN113728515A (en) | Antenna module and communication device having the same mounted thereon | |
| CN117157834A (en) | Antenna module | |
| US8593368B2 (en) | Multi-band antenna and electronic apparatus having the same | |
| US20010007446A1 (en) | Feed circuit for array antenna | |
| CN112189280B (en) | Antenna module and communication device | |
| CN210074169U (en) | Rectangular microstrip series-fed antenna based on grounded coplanar waveguide | |
| CN216354707U (en) | Circuit board and antenna module | |
| US20220328971A1 (en) | Antenna module and communication device equipped with the same | |
| Ghorbani et al. | Ultrabroadband printed (UBP) antenna | |
| US7598914B2 (en) | Wide band co-planar waveguide feeding circularly polarized antenna | |
| CN216015704U (en) | Compact decoupling MIMO terminal antenna for 5G mobile communication | |
| CN113889760B (en) | Compact decoupling MIMO terminal antenna for 5G mobile communication |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |