Coupler, radio frequency circuit and electronic equipment

Abstract

The utility model discloses a coupler, a radio frequency circuit and electronic equipment, the coupler comprises a first transmission line layer and a second transmission line layer, and the first transmission line layer and the second transmission line layer respectively comprise a first transmission line, a first coupling transmission line and a second coupling transmission line; the first end of the first coupling transmission line is connected with the first end of the first transmission line, the first end of the second coupling transmission line is connected with the second end of the first transmission line, and the second end of the first coupling transmission line and the second end of the second coupling transmission line are respectively provided with a connecting port; the first transmission line of the first transmission line layer and the first transmission line of the second transmission line layer are oppositely arranged, and a coupling interval is arranged between the first transmission line of the first transmission line layer and the first transmission line of the second transmission line layer.

Description

Technical Field

[0001] This application relates to the field of electronic product technology, and in particular to a coupler, radio frequency circuit and electronic device. Background Technology

[0002] With the development of mobile communications, mobile phones and other electronic devices will support more and more radio frequency bands to meet increasingly complex communication needs. To support more radio frequency bands, radio frequency front-end devices require larger operating bandwidths or more similar devices. Among these, the coupler is a key component in the radio frequency link, playing a power detection role to maintain the accuracy of the power amplifier's output power. Taking couplers as an example, because traditional couplers have relatively narrow bandwidths, multiple couplers are usually integrated into a communication system to support more radio frequency bands. However, multiple couplers occupy more space on the circuit board of the electronic device, increasing costs. Utility Model Content

[0003] This application provides a coupler, radio frequency circuit, and electronic device to solve the problem of narrow bandwidth in current couplers.

[0004] To solve the above-mentioned technical problems, this application is implemented as follows:

[0005] In a first aspect, embodiments of this application provide a coupler, comprising: a first transmission line layer and a second transmission line layer; wherein...

[0006] The first transmission line layer and the second transmission line layer each include: a first transmission line, a first coupled transmission line, and a second coupled transmission line; a first end of the first coupled transmission line is connected to a first end of the first transmission line, a first end of the second coupled transmission line is connected to a second end of the first transmission line, and the second ends of the first coupled transmission line and the second coupled transmission line are respectively provided with connection ports.

[0007] The first transmission line of the first transmission line layer is disposed opposite to the first transmission line of the second transmission line layer, and there is a coupling gap between the first transmission line of the first transmission line layer and the first transmission line of the second transmission line layer.

[0008] Secondly, embodiments of this application also provide an electronic device, including the coupler described above.

[0009] Thus, in the above-described solution of this application, the coupler, composed of a first transmission line layer and a second transmission line layer respectively including a first transmission line, a first coupled transmission line, and a second coupled transmission line, forms four connection ports of the coupler through connection ports respectively disposed at the second ends of the first and second coupled transmission lines in the first and second transmission lines. Furthermore, by arranging the first transmission lines of the first and second transmission lines opposite each other, and by having a coupling gap between the first transmission lines of the first and second transmission lines, the coupler achieves coupling performance. Moreover, by setting the first and second coupled transmission lines, the bandwidth of the coupler is increased, solving the problem of narrow bandwidth in current couplers. Attached Figure Description

[0010] Figure 1 One of the schematic diagrams showing the structure of the coupler according to an embodiment of this application;

[0011] Figure 2 A second schematic diagram illustrating the structure of the coupler according to an embodiment of this application;

[0012] Figure 3 The third schematic diagram illustrating the structure of the coupler according to an embodiment of this application;

[0013] Figure 4 A schematic diagram illustrating the current transmission of the coupler according to an embodiment of this application;

[0014] Figure 5 A simplified schematic diagram showing the coupler transmission line according to an embodiment of this application;

[0015] Figure 6A This diagram shows the equivalent circuit diagram of the simplified transmission line of the coupler according to an embodiment of this application.

[0016] Figure 6B This diagram illustrates the equivalent circuit diagram of the odd-mode excitation in an embodiment of this application.

[0017] Figure 6C This diagram illustrates the equivalent circuit diagram of even-mode excitation in an embodiment of this application.

[0018] Figure 7 A simulation diagram illustrating the S11 parameters of the coupler in an embodiment of this application;

[0019] Figure 8 A simulation diagram illustrating the S21, S31, and S41 parameters of the coupler in an embodiment of this application.

[0020] Figure 9 One of the schematic diagrams showing the surface current distribution of the coupler according to an embodiment of this application;

[0021] Figure 10 This is a second schematic diagram showing the surface current distribution of the coupler according to an embodiment of this application. Detailed Implementation

[0022] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0023] like Figure 1 As shown, this application embodiment provides a coupler, including: a first transmission line layer 11 and a second transmission line layer 12; wherein,

[0024] The first transmission line layer 11 and the second transmission line layer 12 respectively include: a first transmission line 101, a first coupled transmission line 102, and a second coupled transmission line 103; the first end of the first coupled transmission line 102 is connected to the first end of the first transmission line 101, the first end of the second coupled transmission line 103 is connected to the second end of the first transmission line 101, and the second end of the first coupled transmission line 102 and the second end of the second coupled transmission line 103 are respectively provided with connection ports 13;

[0025] The first transmission line 101 of the first transmission line layer 11 is disposed opposite to the first transmission line 101 of the second transmission line layer 12, and there is a coupling gap between the first transmission line 101 of the first transmission line layer 11 and the first transmission line 101 of the second transmission line layer 12.

[0026] Optionally, the first end and the second end of the first transmission line 101 are arranged opposite to each other, the first end and the second end of the first coupled transmission line 102 are arranged opposite to each other, and the first end and the second end of the second coupled transmission line 103 are arranged opposite to each other.

[0027] Optionally, the first transmission line layer 11 and the second transmission line layer 12 may have the same structure, that is, the first transmission line layer 11 and the second transmission line layer 12 respectively include: a first transmission line 101, a first coupled transmission line 102, and a second coupled transmission line 103.

[0028] Optionally, the first transmission line layer 11 and the second transmission line layer 12 can have a symmetrical structure, for example, the first transmission line layer 11 and the second transmission line layer 12 can be symmetrically arranged with respect to a first direction; or the first transmission line layer 11 and the second transmission line layer 12 can each have a symmetrical structure, for example, the first transmission line layer 11 and the second transmission line layer 12 can each be symmetrically arranged with respect to a second direction. Wherein, the first direction is the extension direction of the coupling interval between the first transmission line 101 of the first transmission line layer 11 and the first transmission line 101 of the second transmission line layer 12, and the second direction is the perpendicular direction of the first transmission line 101.

[0029] For example, the second ends of the first coupled transmission line 102 and the second coupled transmission line 103 of the first transmission line layer 11 are respectively provided with connection ports 13; similarly, the second ends of the first coupled transmission line 102 and the second coupled transmission line 103 of the second transmission line layer 12 are also respectively provided with connection ports 13. Specifically, the connection port 13 located at the second end of the first coupled transmission line 102 of the first transmission line layer 11 can be called the first connection port, the connection port 13 located at the second end of the second coupled transmission line 103 of the first transmission line layer 11 can be called the second connection port, the connection port 13 located at the second end of the first coupled transmission line 102 of the second transmission line layer 12 can be called the third connection port, and the connection port 13 located at the second end of the second coupled transmission line 103 of the second transmission line layer 12 can be called the fourth connection port. In this way, the coupler has four connection ports, which can be used as the signal input port, the through port (or the signal output port), the coupling port, and the isolation port of the coupler, respectively.

[0030] Optionally, the first transmission line 101 of the first transmission line layer 11 and the first transmission line 101 of the second transmission line layer 12 are arranged opposite each other. For example, the first end of the first transmission line 101 of the first transmission line layer 11 is aligned with the first end of the first transmission line 101 of the second transmission line layer 12; the second end of the first transmission line 101 of the first transmission line layer 11 is aligned with the second end of the first transmission line 101 of the second transmission line layer 12, so as to ensure that the coupler in this embodiment has better coupling performance.

[0031] Optionally, the coupling gap between the first transmission line 101 of the first transmission line layer 11 and the first transmission line 101 of the second transmission line layer 12 means that the first transmission line 101 of the first transmission line layer 11 and the first transmission line 101 of the second transmission line layer 12 do not contact each other, but interact with each other through spatial electromagnetic fields at a relatively close distance.

[0032] In this embodiment, a coupler consisting of a first transmission line layer and a second transmission line layer, each including a first transmission line 101, a first coupled transmission line 102, and a second coupled transmission line 103, forms four connection ports on the coupler. These ports are respectively located at the second ends of the first coupled transmission line 102 and the second coupled transmission line 103 in the first and second transmission line layers. Furthermore, by arranging the first transmission lines of the first and second transmission lines opposite each other with a coupling gap, the coupler achieves coupling performance. Additionally, the inclusion of the first coupled transmission line 102 and the second coupled transmission line 103 increases the coupler's bandwidth, thus addressing the current problem of narrow bandwidth in couplers.

[0033] Optionally, the first coupled transmission line 102 and the second coupled transmission line 103 are set at a first preset angle; the first coupled transmission line 102 of the first transmission line layer 11 and the first coupled transmission line 102 of the second transmission line layer 12 are set at a second preset angle; and the second coupled transmission line 103 of the first transmission line layer 11 and the second coupled transmission line 103 of the second transmission line layer 12 are set at a third preset angle.

[0034] The setting of a first preset angle between the first coupling transmission line 102 and the second coupling transmission line 103 means that the first coupling transmission line 102 and the second coupling transmission line 103 are at a relatively large distance to avoid interaction through spatial electromagnetic fields. In other words, the first coupling transmission line 102 and the second coupling transmission line 103 are at a certain angle (or spaced a certain distance) to meet the isolation requirements. The setting of a second preset angle between the first coupling transmission line 102 of the first transmission line layer 11 and the first coupling transmission line 102 of the second transmission line layer 12 means that the first coupling transmission line 102 of the first transmission line layer 11 and the first coupling transmission line 102 of the second transmission line layer 12 are at a relatively large distance to avoid interaction through spatial electromagnetic fields. In other words, the first coupling transmission line 102 of the first transmission line layer 11 and the first coupling transmission line 102 of the second transmission line layer 12 are at a certain angle (or spaced a certain distance) to meet the isolation requirements. The setting of the second coupled transmission line 103 of the first transmission line layer 11 and the second coupled transmission line 103 of the second transmission line layer 12 at a third preset angle means that the second coupled transmission line 103 of the first transmission line layer 11 and the second coupled transmission line 103 of the second transmission line layer 12 are at a relatively large distance to avoid interaction through spatial electromagnetic fields. That is, the second coupled transmission line 103 of the first transmission line layer 11 and the second coupled transmission line 103 of the second transmission line layer 12 are at a certain angle (or at a certain distance) to meet the isolation requirements.

[0035] For example, the extension directions of the first coupling transmission line 102 and the second coupling transmission line 103 are both set at a preset angle to the extension direction of the first transmission line 101. Furthermore, the first coupling transmission line 102 and the second coupling transmission line 103 of the first transmission line layer 11 both extend in a direction away from the second transmission line layer 12, and the first coupling transmission line 102 and the second coupling transmission line 103 of the second transmission line layer 12 both extend in a direction away from the first transmission line layer 11. This ensures that the isolation requirements of the coupler are met between the first coupling transmission line 102 and the second coupling transmission line 103, between the two first coupling transmission lines 102, and between the two second coupling transmission lines 103. This allows the first coupling transmission line 102 and the second coupling transmission line 103 to... The transmission lines 103 are designed to avoid interleaving to reduce coupling between the first coupled transmission line 102 and the second coupled transmission line 103. The first coupled transmission line 102 of the first transmission line layer 11 and the first coupled transmission line 102 of the second transmission line layer 12 are also designed to avoid interleaving to reduce coupling between them. Similarly, the second coupled transmission line 103 of the first transmission line layer 11 and the second coupled transmission line 103 of the second transmission line layer 12 are designed to avoid interleaving to reduce coupling between them. This prevents the coupler from introducing unwanted frequency points within the operating frequency band.

[0036] Specifically, the preset angle (i.e., at least one of the first preset angle, the second preset angle, and the third preset angle) can be set based on the isolation requirements between the first coupled transmission line 102 and the second coupled transmission line 103, the isolation requirements between the first coupled transmission line 102 of the first transmission line layer 11 and the first coupled transmission line 102 of the second transmission line layer 12, and the isolation requirements between the second coupled transmission line 103 of the first transmission line layer 11 and the second coupled transmission line 103 of the second transmission line layer 12. For example, the preset angle can be taken in the range of 0 to 180 degrees. This application embodiment does not make specific limitations.

[0037] Optionally, the length (i.e., electrical length) of the first transmission line 101 satisfies the following:

[0038] Wherein, L1 is the length (i.e., electrical length) of the first transmission line 101; λ is the wavelength corresponding to the center frequency of the coupler.

[0039] For example, the length (i.e., electrical length) of the first transmission line 101 can be determined based on the center frequency of the coupler's operation. For instance, if the center frequency of the coupler needs to be f1, and its corresponding wavelength is λ1, then the electrical length of the first transmission line 101 is...

[0040] It should be noted that the electrical length L1 of the first transmission line 101 can be based on Determine, where σ represents the error, such as the error in the actual manufacturing process, or considering the electrical length L1 of the first transmission line 101 in... When the frequency is near the center frequency of the coupler, the center frequency of the coupler can be reached. Therefore, σ can also represent the error value that satisfies the center frequency of the coupler. The value of σ can be an integer or zero, and the embodiments of this application are not limited thereto.

[0041] In this embodiment, the first transmission line 101 in the first transmission line layer 11 and the second transmission line layer 12 can be used as a common part of the coupler, and its electrical length is set to This ensures that the coupler has a strong coupling coefficient.

[0042] Optionally, the first coupled transmission line 102 is formed by coupling two transmission lines. Specifically, the first coupled transmission line 102 includes: a second transmission line 1021 and a third transmission line 1022; wherein,

[0043] The second transmission line 1021 and the third transmission line 1022 are disposed opposite to each other, and there is a coupling gap between the second transmission line 1021 and the third transmission line 1022;

[0044] The first end of the second transmission line 1021 is provided with the connection port 13, and the first end of the third transmission line 1022 is connected to the first transmission line 101; wherein, the first end of the second transmission line 1021 is disposed away from the first end of the third transmission line 1022.

[0045] For example, the second transmission line 1021 and the third transmission line 1022 are arranged opposite to each other. This can be a portion of the transmission line on the second transmission line 1021 that is away from the first end of the second transmission line 1021 and a portion of the transmission line on the third transmission line 1022 that is away from the first end of the third transmission line 1022, which ensures high coupling performance between the second transmission line 1021 and the third transmission line 1022, and facilitates the setting of the connection port 13 at the first end of the second transmission line 1021, and the connection of the first end of the third transmission line 1022 to the first transmission line 101.

[0046] The coupling interval between the second transmission line 1021 and the third transmission line 1022 means that the second transmission line 1021 and the third transmission line 1022 do not contact each other, but interact with each other through spatial electromagnetic fields at a relatively close distance.

[0047] Optionally, the lengths (i.e., electrical lengths) of the second transmission line 1021 and the third transmission line 1022 respectively satisfy:

[0048] Wherein, L1 is the length (i.e., electrical length) of the second transmission line 1021 or the length (i.e., electrical length) of the third transmission line 1022; λ is the wavelength corresponding to the center frequency of the coupler.

[0049] For example, the electrical lengths of the second transmission line 1021 and the third transmission line 1022 can be determined based on the center frequency of the coupler's operation. For instance, if the center frequency of the coupler is required to be f1, and its corresponding wavelength is λ1, then the electrical lengths of the second transmission line 1021 and the third transmission line 1022 are respectively...

[0050] It should be noted that the electrical length L1 of the second transmission line 1021 and the third transmission line 1022 can be based on... Determined, where σ represents the error, such as the error in the actual processing technology, or considering the electrical length L1 of the second transmission line 1021 and the third transmission line 1022 respectively. When the frequency is near the center frequency of the coupler, the center frequency of the coupler can be reached. Therefore, σ can also represent the error value that satisfies the center frequency of the coupler. The value of σ can be an integer or zero, and the embodiments of this application are not limited thereto.

[0051] Optionally, the second coupled transmission line 103 is formed by coupling two transmission lines. Specifically, the second coupled transmission line 103 includes: a fourth transmission line 1031 and a fifth transmission line 1032; wherein,

[0052] The fourth transmission line 1031 and the fifth transmission line 1032 are arranged opposite to each other, and there is a coupling gap between the fourth transmission line 1031 and the fifth transmission line 1032;

[0053] The first end of the fourth transmission line 1031 is provided with the connection port 13, and the first end of the fifth transmission line 1032 is connected to the first transmission line 101; wherein, the first end of the fourth transmission line 1031 is disposed away from the first end of the fifth transmission line 1032.

[0054] For example, the fourth transmission line 1031 and the fifth transmission line 1032 are arranged opposite to each other. This can be achieved by having a portion of the transmission line on the fourth transmission line 1031 that is away from its first end facing the portion of the transmission line on the fifth transmission line 1032 that is away from its first end. This arrangement ensures high coupling performance between the fourth transmission line 1031 and the fifth transmission line 1032, facilitates the provision of the connection port 13 at the first end of the fourth transmission line 1031, and allows the first end of the fifth transmission line 1032 to be connected to the first transmission line 101.

[0055] The coupling interval between the fourth transmission line 1031 and the fifth transmission line 1032 means that the fourth transmission line 1031 and the fifth transmission line 1032 do not contact each other, but interact with each other through spatial electromagnetic fields at a relatively close distance.

[0056] Optionally, the lengths (i.e., electrical lengths) of the fourth transmission line 1031 and the fifth transmission line 1032 respectively satisfy:

[0057] Wherein, L1 is the length (i.e., electrical length) of the fourth transmission line 1031 or the length (i.e., electrical length) of the fifth transmission line 1032; λ is the wavelength corresponding to the center frequency of the coupler.

[0058] For example, the electrical lengths of the fourth transmission line 1031 and the fifth transmission line 1032 can be determined based on the center frequency of the coupler's operation. For instance, if the center frequency of the coupler needs to be f1, and its corresponding wavelength is λ1, then the electrical lengths of the fourth transmission line 1031 and the fifth transmission line 1032 are respectively...

[0059] It should be noted that the electrical length L1 of the fourth transmission line 1031 and the fifth transmission line 1032 can be based on... Determined, where σ represents the error, such as the error in the actual processing technology, or considering the electrical length L1 of the fourth transmission line 1031 and the fifth transmission line 1032 respectively. When the frequency is near the center frequency of the coupler, the center frequency of the coupler can be reached. Therefore, σ can also represent the error value that satisfies the center frequency of the coupler. The value of σ can be an integer or zero, and the embodiments of this application are not limited thereto.

[0060] In this embodiment, the first coupled transmission line 102 in the first transmission line layer 11 and the second transmission line layer 12 is composed of mutually coupled second transmission line 1021 and third transmission line 1022, and the second coupled transmission line 103 is composed of mutually coupled fourth transmission line 1031 and fifth transmission line 1032, thereby improving the bandwidth of the coupler through impedance matching.

[0061] Optionally, the first transmission line layer 11 and the second transmission line layer 12 further include: a sixth transmission line 104 and / or a seventh transmission line 105, respectively; wherein,

[0062] One end of the sixth transmission line 104 is connected to the second end of the first coupled transmission line 102, and one end of the seventh transmission line 105 is connected to the second end of the second coupled transmission line 103.

[0063] For example, when one end of the sixth transmission line 104 in the first transmission line layer 11 is connected to the second end of the first coupled transmission line 102 in the first transmission line layer 11, the other end of the sixth transmission line 104 can be in an open-circuit state. The sixth transmission line 104 can act as an open-circuit stub, thus optimizing impedance. Similarly, when one end of the sixth transmission line 104 in the second transmission line layer 12 is connected to the second end of the first coupled transmission line 102 in the first transmission line layer 11, the other end of the sixth transmission line 104 can be in an open-circuit state. The sixth transmission line 104 can act as an open-circuit stub, thus optimizing impedance.

[0064] For another example, when one end of the seventh transmission line 105 in the first transmission line layer 11 is connected to the second end of the second coupled transmission line 103 in the first transmission line layer 11, the other end of the seventh transmission line 105 can be in an open circuit state. The seventh transmission line 105 can act as an open circuit stub to optimize impedance. Similarly, when one end of the seventh transmission line 105 in the second transmission line layer 12 is connected to the second end of the second coupled transmission line 103 in the second transmission line layer 12, the other end of the seventh transmission line 105 can be in an open circuit state. The seventh transmission line 105 can act as an open circuit stub to optimize impedance.

[0065] Optionally, such as Figure 1 As shown, the sixth transmission line 104 is a straight transmission line, or as... Figure 2 As shown, the sixth transmission line 104 is a transmission line with at least one bend.

[0066] Optionally, the sixth transmission line 104 may be arranged in a direction away from the first transmission line 101, or the sixth transmission line 104 may be arranged in a direction closer to the first transmission line 101.

[0067] For example, when the sixth transmission line 104 is a straight transmission line, in order to ensure the isolation requirement of the sixth transmission line 104, the sixth transmission line 104 can be arranged in a direction away from the first transmission line 101.

[0068] For another example, when the sixth transmission line 104 is a transmission line provided with at least one bent portion, one or more bent portions can be provided on the sixth transmission line 104. For example, the angle of the bent portion can be within the range of 0 to 180 degrees. Optionally, the angle of the bent portion can be 90 degrees. For example, the sixth transmission line 104 can be in an "L" shape, or a "U" shape, or an "inverted U" shape, or a "square frame" shape, etc. The embodiments of the present application are not limited thereto.

[0069] By providing one or more bent portions on the sixth transmission line 104, the space occupied by the sixth transmission line 104 on the circuit board can be reduced, and thus the space occupied by the coupler on the circuit board can be reduced. At the same time, considering that the sixth transmission line 104 is provided with at least one bent portion, the occupied space can be reduced. Therefore, for the sixth transmission line 104 provided with at least one bent portion, when the isolation requirement is met, it can be arranged in a direction away from the first transmission line 101, or arranged in a direction close to the first transmission line 101.

[0070] Optionally, as Figure 1 shown, the seventh transmission line 105 is a straight transmission line, or as Figure 2 shown, the seventh transmission line 105 is a transmission line provided with at least one bent portion.

[0071] Optionally, the seventh transmission line 105 can be arranged in a direction away from the first transmission line 101, or the seventh transmission line 105 can be arranged in a direction close to the first transmission line 101.

[0072] For example, when the seventh transmission line 105 is a straight transmission line, in order to ensure the isolation requirement of the seventh transmission line 105, the seventh transmission line 105 can be arranged in a direction away from the first transmission line 101.

[0073] For another example, when the seventh transmission line 105 is a transmission line provided with at least one bent portion, one or more bent portions can be provided on the seventh transmission line 105. For example, the angle of the bent portion can be within the range of 0 to 180 degrees. Optionally, the angle of the bent portion can be 90 degrees. For example, the sixth transmission line 104 can be in an "L" shape, or a "U" shape, or an "inverted U" shape, or a "square frame" shape, etc. The embodiments of the present application are not limited thereto.

[0074] By providing one or more bends in the seventh transmission line 105, the space occupied by the seventh transmission line 105 on the circuit board can be reduced, thereby reducing the space occupied by the coupler on the circuit board. Furthermore, considering that the seventh transmission line 105 has at least one bend, which reduces its space occupation, the seventh transmission line 105 with at least one bend can be positioned either in a direction away from the first transmission line 101 or in a direction closer to the first transmission line 101, provided that isolation requirements are met.

[0075] Optionally, the lengths (i.e., electrical lengths) of the sixth transmission line 104 and the seventh transmission line 105 respectively satisfy:

[0076] Wherein, L2 is the length of the sixth transmission line 104 or the length (i.e., electrical length) of the seventh transmission line 105; λ is the wavelength corresponding to the center frequency of the coupler.

[0077] For example, the electrical lengths of the sixth transmission line 104 and the seventh transmission line 105 can be determined based on the center frequency of the coupler's operation. For instance, if the center frequency of the coupler is required to be f1, and its corresponding wavelength is λ1, then the electrical lengths of the sixth transmission line 104 and the seventh transmission line 105 are respectively...

[0078] It should be noted that the electrical length L2 of the sixth transmission line 104 and the seventh transmission line 105 can be based on... Determined, where σ represents the error, such as the error in the actual processing technology, or considering the electrical length L2 of the sixth transmission line 104 and the seventh transmission line 105 respectively. When the frequency is near the center frequency of the coupler, the center frequency of the coupler can be reached. Therefore, σ can also represent the error value that satisfies the center frequency of the coupler. The value of σ can be an integer or zero, and the embodiments of this application are not limited thereto.

[0079] Optionally, the first transmission line layer 11 and the second transmission line layer 12 further include: a first connecting line 106 and a second connecting line 107, respectively; wherein,

[0080] The first end of the first connecting line 106 is connected to the second end of the first coupling transmission line 102, the first end of the second connecting line 107 is connected to the second end of the second coupling transmission line 103, and the second ends of the first connecting line 106 and the second connecting line 107 are respectively provided with the connecting port 13.

[0081] For example, the first connection line 106 in the first transmission line layer 11 can be connected to the first connection port and the second end of the first coupled transmission line 102 in the first transmission line layer 11. Here, the first connection line 106 serves to connect the first connection port and the second end of the first coupled transmission line 102 in the first transmission line layer 11. Similarly, the first connection line 106 in the second transmission line layer 12 can be connected to the third connection port and the second end of the first coupled transmission line 102 in the second transmission line layer 12. Here, the first connection line 106 serves to connect the third connection port and the second end of the first coupled transmission line 102 in the second transmission line layer 12. The first connection port is the connection port 13 located at the second end of the first coupled transmission line 102 in the first transmission line layer 11; the third connection port is the connection port 13 located at the second end of the first coupled transmission line 102 in the second transmission line layer 12.

[0082] For another example, the second connection line 107 in the first transmission line layer 11 can be connected to the second connection port and the second end of the second coupled transmission line 103 in the first transmission line layer 11. Here, the second connection line 107 serves to connect the second connection port and the second end of the second coupled transmission line 103 in the first transmission line layer 11. Similarly, the second connection line 107 in the second transmission line layer 12 can be connected to the fourth connection port and the second end of the second coupled transmission line 103 in the second transmission line layer 12. Here, the second connection line 107 serves to connect the fourth connection port and the second end of the second coupled transmission line 103 in the second transmission line layer 12. The second connection port is the connection port 13 located at the second end of the second coupled transmission line 103 in the first transmission line layer 11; the fourth connection port is the connection port 13 located at the second end of the second coupled transmission line 103 in the second transmission line layer 12.

[0083] Optionally, such as Figure 3 As shown, the coupler further includes: a reference ground layer 18 and a dielectric substrate 19; wherein,

[0084] The first transmission line layer 11 and the second transmission line layer 12 are disposed on the first surface of the dielectric substrate 19, and the reference ground layer 18 is disposed on the second surface of the dielectric substrate 19; wherein the first surface and the second surface are disposed opposite to each other;

[0085] Each of the connection ports 13 is connected to the reference formation.

[0086] For example, each of the connection ports 13 may include two connection ends. For the first connection port (i.e., the connection port located at the second end of the first coupled transmission line 102 in the first transmission line layer 11), one connection end is connected to the reference ground layer, and the other connection end is connected to the second end of the first coupled transmission line 102 in the first transmission line layer 11; for the second connection port (i.e., the connection port located at the second end of the second coupled transmission line 103 in the first transmission line layer 11), one connection end is connected to the reference ground layer, and the other connection end is connected to the second end of the second coupled transmission line 103 in the first transmission line layer 11; for the third connection port (i.e., the connection port located at the second end of the first coupled transmission line 102 in the second transmission line layer 12), one connection end is connected to the reference ground layer, and the other connection end is connected to the second end of the first coupled transmission line 102 in the second transmission line layer 12; for the fourth connection port (i.e., the connection port located at the second end of the second coupled transmission line 103 in the second transmission line layer 12), one connection end is connected to the reference ground layer, and the other connection end is connected to the second end of the second coupled transmission line 103 in the second transmission line layer 12.

[0087] Optionally, the connection port 13 at the second end of the first coupling transmission line 102 in the first transmission line layer 11 is the signal input port 131 of the coupler; the connection port 13 at the second end of the second coupling transmission line 103 in the first transmission line layer 11 is the through port 132 of the coupler; the connection port 13 at the second end of the first coupling transmission line 102 in the second transmission line layer 12 is the coupling port 133 of the coupler; and the connection port 13 at the second end of the second coupling transmission line 103 in the second transmission line layer 12 is the isolation port 134 of the coupler.

[0088] For ease of description, the connection port 13 at the second end of the first coupled transmission line 102 in the first transmission line layer 11 can be called the first connection port, which can serve as the signal input port (or input port) of the coupler; the connection port 13 at the second end of the second coupled transmission line 103 in the first transmission line layer 11 can be called the second connection port, which can serve as the through port (or output port or signal output port) of the coupler; the connection port 13 at the second end of the first coupled transmission line 102 in the second transmission line layer 12 can be called the third connection port, which can serve as the coupling port of the coupler; and the connection port 13 at the second end of the second coupled transmission line 103 in the second transmission line layer 12 can be called the fourth connection port, which can serve as the isolation port of the coupler. Alternatively, if the first transmission line layer 11 and the second transmission line layer 12 have the same structure but different layout orientations, the functions of the first and third connection ports can be interchanged, as can the functions of the second and fourth connection ports. For example, the third connection port can serve as the input port of the coupler, the first connection port as the coupling port of the coupler, the fourth connection port as the through port of the coupler, and the second connection port as the isolation port of the coupler. Alternatively, the functions of the first and second connection ports, as well as the functions of the third and fourth connection ports, can be interchanged. For example, the second connection port can serve as the input port of the coupler, the first connection port as the through port of the coupler, the fourth connection port as the coupling port of the coupler, and the third connection port as the isolation port of the coupler, etc. The embodiments of this application are not limited to these.

[0089] For ease of explanation, in the following embodiments, the first connection line 106 in the first transmission line layer 11 is referred to as TL1, the sixth transmission line 104 in the first transmission line layer 11 is referred to as TL1_1, the second transmission line 1021 in the first transmission line layer 11 is referred to as TL1_2, the third transmission line 1022 in the first transmission line layer 11 is referred to as TL1_3, the first transmission line 101 in the first transmission line layer 11 is referred to as LT5, the second connection line 107 in the first transmission line layer 11 is referred to as TL2, the seventh transmission line 105 in the first transmission line layer 11 is referred to as TL2_1, the fourth transmission line 1031 in the first transmission line layer 11 is referred to as TL2_2, and the fifth transmission line 1032 in the first transmission line layer 11 is referred to as TL1_2. The first connection line 106 in the second transmission line layer 12 is denoted as TL3, the sixth transmission line 104 in the second transmission line layer 12 is denoted as TL3_1, the second transmission line 1021 in the second transmission line layer 12 is denoted as TL3_2, the third transmission line 1022 in the second transmission line layer 12 is denoted as TL3_3, the first transmission line 101 in the second transmission line layer 12 is denoted as LT6, the second connection line 107 in the second transmission line layer 12 is denoted as TL4, the seventh transmission line 105 in the second transmission line layer 12 is denoted as TL4_1, the fourth transmission line 1031 in the second transmission line layer 12 is denoted as TL4_2, and the fifth transmission line 1032 in the second transmission line layer 12 is denoted as TL4_3. Taking the signal input port 131 of the coupler as Port1, the through port 132 as Port2, the coupling port 133 as Port3, and the isolation port 134 as Port4 as an example, the signal transmission process of the coupler in this embodiment of the application will be described as follows:

[0090] like Figure 4 As shown, the signal is input from Port1, flows through TL1, then through TL1_2, and due to the coupling effect of TL1_2 and TL1_3, the signal flows out from transmission line TL1_3, and then flows through TL5 (as shown). Figure 4 (As shown by the solid red arrow in the middle). The signal flowing out of TL5 is divided into two parts: one part passes through the directly connected TL2_3, and then, due to the coupling effect of TL2_2 and TL2_3, flows out from TL2_2, through TL2, and into Port2 (as shown by the arrow in the middle). Figure 4 (As shown by the red dashed arrow in the middle) Therefore, the coupled port corresponding to Port2 is called a through port or a direct signal output port. Another part of the signal flowing out from TL5, due to the coupling effect of the two couplers TL5 and TL6, flows out from TL6, passes through the directly connected TL3_3, and then, due to the coupling effect of TL3_3 and TL3_2, flows out from TL3_2, passes through TL3, and flows into Port3 (as shown by the red dashed arrow in the middle). Figure 4(As shown by the solid blue arrow in the middle) Since the signal flowing from TL5 into TL6 is transmitted through coupling, the connection port corresponding to Port3 is called the coupling port.

[0091] For ease of explanation, Figure 4 The transmission line structure of the coupler in the image is simplified to: Figure 4 The simplified structure shown is used to illustrate the principle that Port3 has a signal output while Port4 does not during signal transmission in the coupler of this embodiment:

[0092] based on Figure 5 The simplified structure shown yields Figure 6A The equivalent circuit diagram shown depicts Port1 driven by a 2V0 voltage source with an internal resistance of Z0. Ports 2, 3, and 4 are each connected to a load impedance Z0. Port 1 is the input port, Port 2 is a through port, Port 3 is a coupling port, and Port 4 is an isolation port. I1 represents the current in Port 1, and V1 represents the voltage in Port 1; I2 represents the current in Port 2, and V2 represents the voltage in Port 2; I3 represents the current in Port 3, and V3 represents the voltage in Port 3; I4 represents the current in Port 4, and V3 represents the voltage in Port 4. θ = βl. λ is the wavelength, and l is the electrical length of the transmission line.

[0093] Using the superposition theorem, Figure 6A The stimulus of Port1 can be equivalent to Figure 6B The even-mode excitation shown is Figure 6C The superposition of odd-mode excitations is shown.

[0094] Due to symmetry, for even modes we have:

[0095] For odd models:

[0096] Figure 6A The input impedance of the coupler shown at Port1 is expressed as:

[0097]

[0098] If let Figure 6B and Figure 6C The input impedance of the even mode at Port1 is The input impedance of the odd mode is but:

[0099]

[0100]

[0101] Among them, Z 0e The characteristic impedance of the transmission line when it is excited in even mode; Z 0o The characteristic impedance of the transmission line when it is excited by odd mode.

[0102] according to Figure 6B and Figure 6C According to Ohm's law, the voltage division formula is:

[0103]

[0104] And, according to Ohm's law, we can obtain:

[0105]

[0106] Substituting formulas (1-4), (1-5), (1-6), and (1-7) into (1-1), we get:

[0107]

[0108] If so,

[0109]

[0110] Substituting formula (1-9) into (1-2) and (1-3) respectively, we get:

[0111]

[0112] but,

[0113]

[0114] Substituting formula (1-12) into (1-8), we get:

[0115] Z in =Z0 (1-13) according to Figure 6A According to Ohm's law, the voltage division formula is:

[0116] V1 = V0 (1-14) Therefore, if formula (1-9) is satisfied, then Port1 is matched. The voltage at Port3 is:

[0117]

[0118] Substituting formulas (1-10) and (1-11) into (1-15), we get:

[0119]

[0120] make but The voltage at Port3 is then expressed as:

[0121]

[0122] Voltage at Port4: because Therefore, V4 = 0. Similarly, the voltage at Port2 is: Since the voltage at Port4 is 0, according to Ohm's law, the current is 0. Therefore, in Figure 5 The signal is input from Port1, output directly from Port2, coupled out from Port3, and there is no signal output from Port4, hence Port4 is called the isolation port.

[0123] based on Figure 4 The coupler structure shown was simulated to obtain... Figure 7 The simulation diagram of the S11 parameters shown indicates that the frequency range of S11 < -10dB is 2.16GHz to 4.82GHz, and there are four resonant points ①, ②, ③, and ④ within the operating frequency band. This coupler introduces four pairs of... The coupled transmission lines, namely TL1_2 and TL1_3, TL2_2 and TL2_3, TL3_2 and TL3_3, and TL4_2 and TL4_3, provide resonant points ①, ②, ③, and ④ within the passband, thus ensuring good matching within the operating frequency band and expanding the coupler's bandwidth. Furthermore, the four pairs of open-circuit stubs, namely TL1_1, TL2_1, TL3_1, and TL4_1, optimize the impedance, further enhancing the coupler's bandwidth.

[0124] It should be noted here that the number of resonant points when this coupler is working is related to... The number of coupled transmission lines is not necessarily related. Depending on the environment in which the coupled transmission line is located, the number of corresponding resonant points may be multiple, and is not limited to 4 resonant points.

[0125] based on Figure 4 The coupler structure shown was simulated to obtain... Figure 8 The simulation diagrams for parameters S21, S31, and S41 shown indicate that, based on S21, the insertion loss is approximately -1.7 dB within the passband. Based on S31, the coupling coefficient of the coupler is between -10 dB and -20 dB within the passband (the coupling coefficient fluctuates slightly and can be improved by optimizing relevant microstrip line parameters, such as adjusting the microstrip line size and spacing). Based on S41, the coupler exhibits good isolation performance within the passband, with S41 < -20 dB. Figure 9 , Figure 10 The surface current distribution of the coupler was simulated from... Figure 9 , Figure 10It can be seen that the open-circuit stubs, namely TL1_1, TL2_1, TL3_1, and TL4_1, can play a role in regulating the direction of some currents and affecting the impedance of the coupler.

[0126] This application embodiment increases the operating bandwidth of the coupler. For current electronic devices such as mobile phones, due to the limitation of the coupler's operating bandwidth, it is necessary to design couplers suitable for different frequency bands separately, and increase the number of couplers to meet communication requirements. Using the coupler in this application embodiment, because its operating bandwidth is larger, it can be applied to different frequency bands, thereby reducing the number of couplers required. This not only reduces the space occupied by the device on the circuit board layout, but also reduces the device cost.

[0127] This application provides a radio frequency circuit, including the coupler described above, and further including: a first radio frequency unit, a second radio frequency unit, and a power amplifier unit; wherein,

[0128] The signal input port 131 of the coupler is connected to the power amplifier unit, the through port 132 of the coupler is connected to the first radio frequency unit, the coupling port 133 of the coupler is connected to the second radio frequency unit, and the isolation port 134 of the coupler is connected to the load unit.

[0129] Optionally, the signal input port 131 can be a connection port located at the second end of the first coupled transmission line 102 in the first transmission line layer 11, the through port 132 can be a connection port located at the second end of the second coupled transmission line 103 in the first transmission line layer 11, the coupling port 133 can be a connection port located at the second end of the first coupled transmission line 102 in the second transmission line layer 12, and the isolation port 134 can be a connection port located at the second end of the second coupled transmission line 103 in the second transmission line layer 12.

[0130] For example: the power amplifier unit can be a power amplifier, that is, the signal input port 131 of the coupler can be connected to the back end of the power amplifier; the first radio frequency unit and the second radio frequency unit can be different radio frequency devices, that is, the through port 132 and the coupling port 133 of the coupler are respectively connected to two radio frequency devices; the load unit can be a resistor (e.g., a 50-ohm resistor), that is, the isolation port 134 of the coupler can be connected to a 50-ohm resistor.

[0131] It should be noted that the radio frequency circuit in the embodiments of this application can implement various embodiments of the above-mentioned coupler and achieve the same technical effect. To avoid repetition, it will not be described again here.

[0132] This application provides an electronic device including the coupler described above.

[0133] This application also provides an electronic device, including the radio frequency circuit described above.

[0134] Optionally, the electronic device includes, but is not limited to, mobile phones, tablets, laptops, wearable devices (e.g., smartwatches, smart bracelets, smart glasses, etc.), or other electronic devices with radio frequency circuits, etc., and the embodiments of this application are not limited thereto.

[0135] It should be noted that the electronic devices in the embodiments of this application can implement various embodiments of the coupler in the above-mentioned radio frequency circuit and achieve the same technical effect. To avoid repetition, they will not be described again here.

[0136] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0137] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0138] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0139] The above describes the preferred embodiments of this application. It should be noted that those skilled in the art can make several improvements and modifications without departing from the principles described in this application, and these improvements and modifications are also within the protection scope of this application.

Claims

1. A coupler, characterized in that, include: A first transmission line layer and a second transmission line layer; wherein the first transmission line layer and the second transmission line layer respectively include: a first transmission line, a first coupled transmission line, and a second coupled transmission line; The first end of the first coupling transmission line is connected to the first end of the first transmission line, and the first end of the second coupling transmission line is connected to the second end of the first coupling transmission line. The second ends of the first coupling transmission line and the second ends of the second coupling transmission line are respectively provided with connection ports. The first transmission line of the first transmission line layer is disposed opposite to the first transmission line of the second transmission line layer, and there is a coupling gap between the first transmission line of the first transmission line layer and the first transmission line of the second transmission line layer.

2. The coupler according to claim 1, characterized in that, The first coupled transmission line and the second coupled transmission line are set at a first preset angle; The first coupled transmission line of the first transmission line layer and the first coupled transmission line of the second transmission line layer are set at a second preset angle; The second coupled transmission line of the first transmission line layer and the second coupled transmission line of the second transmission line layer are set at a third preset angle.

3. The coupler according to claim 1, characterized in that, The first coupled transmission line includes: a second transmission line and a third transmission line; wherein, The second transmission line and the third transmission line are disposed opposite to each other, and there is a coupling gap between the second transmission line and the third transmission line; The first end of the second transmission line is provided with the connection port, and the first end of the third transmission line is connected to the first transmission line; wherein, the first end of the second transmission line is disposed away from the first end of the third transmission line.

4. The coupler according to claim 1, characterized in that, The second coupled transmission line includes: a fourth transmission line and a fifth transmission line; wherein, The fourth transmission line and the fifth transmission line are arranged opposite to each other, and there is a coupling gap between the fourth transmission line and the fifth transmission line; The first end of the fourth transmission line is provided with the connection port, and the first end of the fifth transmission line is connected to the first transmission line; wherein, the first end of the fourth transmission line is disposed away from the first end of the fifth transmission line.

5. The coupler according to any one of claims 1 to 4, characterized in that, The lengths of the first transmission line, the second transmission line, the third transmission line, the fourth transmission line, and the fifth transmission line respectively satisfy the following: Wherein, L1 is the length of the first transmission line, or the length of the second transmission line, or the length of the third transmission line, or the length of the fourth transmission line, or the length of the fifth transmission line; λ is the wavelength corresponding to the center frequency of the coupler.

6. The coupler according to claim 1, characterized in that, The first transmission line layer and the second transmission line layer further include: a sixth transmission line and / or a seventh transmission line, respectively; wherein, One end of the sixth transmission line is connected to the second end of the first coupled transmission line, and one end of the seventh transmission line is connected to the second end of the second coupled transmission line.

7. The coupler according to claim 6, characterized in that, The sixth transmission line is a straight transmission line, or the sixth transmission line is a transmission line with at least one bend. The seventh transmission line is a straight transmission line, or the seventh transmission line is a transmission line with at least one bend.

8. The coupler according to claim 6, characterized in that, The lengths of the sixth transmission line and the seventh transmission line respectively satisfy: Where L2 is the length of the sixth transmission line or the length of the seventh transmission line; λ is the wavelength corresponding to the center frequency of the coupler.

9. The coupler according to claim 1, characterized in that, The first transmission line layer and the second transmission line layer further include: a first connection line and a second connection line, respectively; wherein, The first end of the first connecting line is connected to the second end of the first coupled transmission line, and the first end of the second connecting line is connected to the second end of the second coupled transmission line. The second ends of the first connecting line and the second connecting line are respectively provided with the connection port.

10. The coupler according to claim 1, characterized in that, The connection port at the second end of the first coupled transmission line located in the first transmission line layer is the signal input port of the coupler; the connection port at the second end of the second coupled transmission line located in the first transmission line layer is the through port of the coupler. The connection port at the second end of the first coupled transmission line located in the second transmission line layer is the coupling port of the coupler. The connection port at the second end of the second coupled transmission line located in the second transmission line layer is the isolation port of the coupler.

11. The coupler according to claim 1, characterized in that, Also includes: Reference layer and dielectric substrate; wherein, The first transmission line layer and the second transmission line layer are disposed on the first surface of the dielectric substrate, and the reference ground layer is disposed on the second surface of the dielectric substrate; wherein the first surface and the second surface are disposed opposite to each other; Each of the connection ports is connected to the reference formation.

12. An electronic device, characterized in that, Includes the coupler as described in any one of claims 1 to 11.

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