Directional coupling circuit and electronic equipment
By integrating a ring-shaped tubular path and a microstrip line inside a printed circuit board to form a directional coupling circuit, the problem of high cost of directional couplers in the prior art is solved, achieving cost savings and reduced signal loss.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-23
- Publication Date
- 2026-03-31
AI Technical Summary
Existing technologies require that directional couplers be manufactured separately or purchased from external suppliers when applied to printed circuit boards, resulting in high costs.
By integrating a ring-shaped tubular path and a microstrip line inside the printed circuit board, a directional coupling circuit is formed to achieve directional coupling function, avoiding the need to separately manufacture or purchase directional couplers.
It reduces cost investment and avoids signal loss problems caused by excessively long windings in traditional microstrip lines through a simple microstrip line structure.
Smart Images
Figure CN224067881U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of directional coupler technology, and further to a directional coupling circuit and electronic device. Background Technology
[0002] In the design and manufacturing of printed circuit boards (PCBs), directional couplers are crucial components for enabling signal transmission, power distribution, and detection. However, current technologies typically require either custom manufacturing or sourcing directional couplers from external suppliers when applying them to PCBs. Both in-house manufacturing and external sourcing incur additional costs. Utility Model Content
[0003] To address the aforementioned technical problems, this application provides a directional coupling circuit and electronic device that reduces cost.
[0004] In a first aspect, this application provides a directional coupling circuit, comprising: a printed circuit board; a signal transceiver disposed on the top layer of the printed circuit board; a ring-shaped tubular path disposed in the printed circuit board, wherein the input port of the ring-shaped tubular path is connected to the signal transceiver, and the through port of the ring-shaped tubular path is connected to an external device for transmitting the input signal sent by the signal transceiver to the external device; a microstrip line disposed between the top and bottom layers of the printed circuit board, the microstrip line being parallel to and passing through the ring-shaped tubular path, and the coupling port of the microstrip line being connected to the signal transceiver; the ring-shaped tubular path is further used to couple the input signal to the microstrip line, so that the microstrip line generates a directional coupling signal; the microstrip line is used to send the directional coupling signal to the signal transceiver, so that the signal transceiver performs power detection on the input signal based on the directional coupling signal.
[0005] This directional coupling circuit comprises a signal transceiver located on the top layer of a printed circuit board (PCB), a ring-shaped tubular path within the PCB, and a microstrip line between the top and bottom layers. The input port of the ring-shaped tubular path connects to the signal transceiver, while its through port connects to an external device for transmitting the input signal. The microstrip line runs parallel to and through the ring-shaped tubular path, with its coupling port connected to the signal transceiver. The ring-shaped tubular path couples the input signal to the microstrip line, generating a directional coupled signal. The microstrip line then transmits this signal back to the signal transceiver for power detection. This design integrates the ring-shaped tubular path and the microstrip line within the PCB, enabling the final PCB to function as a directional coupler. This avoids the need for separate fabrication or sourcing of directional couplers from external suppliers, typically required when applying directional couplers to PCBs, thus reducing costs. Furthermore, the microstrip line structure in this embodiment is simple, directly penetrating the top and bottom layers of the PCB, avoiding signal loss issues caused by excessively long windings in traditional methods.
[0006] In one implementation, the outer surface of the annular tubular passage is insulated, while the inner wall is a hollow coaxial line.
[0007] In one implementation, an impedance path is attached to the inner wall of the annular tubular passage, wherein the linewidth of the impedance path is any value between 0.1 mm and 0.3 mm, and the characteristic impedance of the impedance path is any value between 50 ohms and 52 ohms.
[0008] In one implementation, the isolation port of the microstrip line is located on the top layer of the printed circuit board, and the coupling port is located on the bottom layer of the printed circuit board.
[0009] In one implementation, an annular tubular passage is disposed between the second and fifth layers of the printed circuit board.
[0010] In one implementation, the microstrip line is a fin-shaped microstrip line.
[0011] In one implementation, the external device includes an antenna.
[0012] In one implementation, the width of the microstrip line is any value between 0.1 mm and 0.3 mm, and the distance between the outer surface of the microstrip line and the inner wall of the annular tubular passage is any value between 0.25 mm and 0.45 mm.
[0013] Secondly, this application also provides an electronic device including a directional coupling circuit implemented according to any of the above claims.
[0014] In one implementation, the electronic device is an inter-board ring directional coupler.
[0015] Compared with the prior art, the present invention has the following beneficial effects:
[0016] The circuit board (PCB) includes a signal transceiver located on the top layer, a ring-shaped tubular path within the PCB, and a microstrip line between the top and bottom layers. The input port of the ring-shaped tubular path connects to the signal transceiver, while its through port connects to an external device for transmitting the input signal. The microstrip line runs parallel to and through the ring-shaped tubular path, with its coupling port connected to the signal transceiver. The ring-shaped tubular path couples the input signal to the microstrip line, generating a directional coupled signal. The microstrip line then transmits this signal back to the signal transceiver for power detection. This design integrates the ring-shaped tubular path and the microstrip line within the PCB, enabling the final PCB to function as a directional coupler. This avoids the need for separate fabrication or sourcing of directional couplers from external suppliers, typically required when applying directional couplers to PCBs, thus reducing costs. Furthermore, the microstrip line structure in this embodiment is simple, directly penetrating the top and bottom layers of the PCB, avoiding signal loss issues caused by excessively long windings in traditional circuits. Attached Figure Description
[0017] The preferred embodiments will be described below in a clear and easy-to-understand manner, in conjunction with the accompanying drawings, to further explain the above-mentioned characteristics, technical features, advantages and implementation methods of this utility model.
[0018] Figure 1 A schematic diagram of a directional coupling circuit provided in an embodiment of this application is shown;
[0019] Figure 2 The illustration shows a front view and a top view of an annular tubular passage provided in an embodiment of this application. Detailed Implementation
[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the specific implementation methods of this utility model will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of this utility model. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.
[0021] To keep the drawings concise, each figure only schematically shows the parts relevant to the utility model, and these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of the components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."
[0022] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.
[0023] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0024] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0025] It should be noted that the above embodiments can be freely combined as needed. The above are merely preferred embodiments of this utility model. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.
[0026] A directional coupler is an important passive device in microwave and radio frequency circuits. Its main function is to couple a portion of the signal from a transmission line in a specific direction while maintaining the directionality of signal transmission on the main transmission line. Directional couplers are commonly used in power measurement, signal distribution, signal monitoring, antenna coupling, and radar systems.
[0027] In some designs, a directional coupler can be formed by two parallel and close transmission lines; alternatively, it can be formed on a printed circuit board by multiple parallel transmission lines configured in a rotating pattern; furthermore, the directional coupler can also employ independent microwave devices and modules. This application embodiment, by setting corresponding annular tubular pathways and microstrip lines during the printed circuit board manufacturing process, enables the directional coupling circuit obtained in this application embodiment to possess the function of a directional coupler, thereby avoiding the need for separate fabrication or procurement from external suppliers when applying directional couplers to printed circuit boards, thus reducing cost.
[0028] The following explanation is based on the accompanying diagram:
[0029] Reference Appendix Figure 1 This illustrates a schematic diagram of a directional coupling circuit provided in an embodiment of this application. Figure 1 As shown, it includes: a printed circuit board (see attached document). Figure 1 The motherboard consists of several layers forming a printed circuit board, including a signal transceiver 100, a ring-shaped tubular path 200, and a microstrip line 300. The signal transceiver 100 is located on the top layer of the printed circuit board (see attached diagram). Figure 1 The circuit board has a ring-shaped tubular path 200 installed on its top and bottom layers. The input port S1 of the ring-shaped tubular path 200 is connected to the signal transceiver 100, and the through port (or output port) S2 of the ring-shaped tubular path 200 is connected to an external device to transmit the input signal sent by the signal transceiver 100 to the external device. Microstrip lines 300 are installed on the top and bottom layers of the printed circuit board (see attached diagram). Figure 1Between the motherboard bottom layer and the ring tubular path 200, the microstrip line 300 is parallel to and passes through the ring tubular path 200, and the coupling port S3 of the microstrip line 300 is connected to the signal transceiver 100; the ring tubular path 200 is also used to couple the input signal to the microstrip line 300, so that the microstrip line 300 generates a directional coupling signal; the microstrip line 300 is used to send the directional coupling signal to the signal transceiver 100, so that the signal transceiver 100 performs power detection on the input signal based on the directional coupling signal.
[0030] The transmission lines connecting the transceiver 100 to the input port S1 of the ring-shaped channel 200, the transmission lines connecting the through port S2 of the ring-shaped channel 200 to external devices, and the transmission lines connecting the coupling port S3 of the microstrip line 300 to the transceiver 100 are all 51-ohm impedance lines. Furthermore, these transmission lines need to pass through different motherboard layers; therefore, vias corresponding to these transmission lines are provided on each layer of the printed circuit board.
[0031] The annular tubular passage 200 can be arranged between different layers of the printed circuit board according to user requirements. For example, the annular tubular passage 200 can be arranged on the second layer of the printed circuit board (see attached diagram). Figure 1 The inner layer 2 of the motherboard and the fifth layer (see attached) Figure 1 Between the inner layers 5 of the motherboard; or, for example, it can be set in the third layer of the printed circuit board (essentially the inner layer 3 of the motherboard, with attached...). Figure 1 The locations of the annular tubular passages 200 (not shown) and the bottom layer of the printed circuit board are not listed here. In fact, the placement of the annular tubular passage 200 is related to the vias mentioned above. The annular tubular passage 200 can be placed on the main board layer of the printed circuit board according to which vias the aforementioned transmission lines pass through.
[0032] The toroidal path 200 and the microstrip line 300 constitute a directional coupler. The working principle of this directional coupler is explained below with the toroidal path 200 positioned between the second and fifth layers of a printed circuit board (PCB): The transceiver 100 sends an input signal. This input signal travels along the transmission line connecting the transceiver 100 and the input port S1 of the toroidal path 200, first on the top layer of the PCB, then through a via between the top and second layers to reach the second layer, and further to the input port S1 of the toroidal path 200. Then, the input signal travels from input port S1 to through port S2, and further on the fifth layer of the PCB. Through a via between the fifth and top layers, the input signal returns to the top layer of the PCB, and is finally transmitted to an external device. Simultaneously, as the input signal passes through the toroidal path 200, it couples to the microstrip line 300, causing the microstrip line 300 to generate a directional coupling signal. The directionally coupled signal travels along the transmission line connecting the coupling port S3 of the microstrip line 300 and the transceiver 100 on the bottom layer of the printed circuit board (PCB). Then, through a via between the bottom and top layers of the PCB, the directionally coupled signal returns to the top layer and is finally received by the transceiver 100, enabling the transceiver 100 to perform power detection on the input signal based on the directionally coupled signal. When the annular tubular path 200 is placed on another PCB layer, its operating principle is the same as described above, except that the PCB layer through which the input signal passes differs.
[0033] External devices can be chosen from a variety of options depending on the application scenario. For example, including but not limited to, in the field of wireless communication, external devices can be antennas (see attached). Figure 1 In a radio frequency (RF) front-end module, an antenna can transmit the input signal into the air in the form of electromagnetic waves, thereby realizing the function of wireless communication. In applications such as wireless communication base stations and radar systems that require high-power signal transmission, external devices can be power amplifiers, which can be used to amplify the power of the input signal. In the RF front-end module, external devices can be filters, which are used for preprocessing of the input signal, etc.
[0034] This embodiment of the application includes a signal transceiver located on the top layer of the printed circuit board (PCB), a ring-shaped tubular path within the PCB, and a microstrip line located between the top and bottom layers. The input port of the ring-shaped tubular path connects to the signal transceiver, and the through port connects to an external device for transmitting input signals. The microstrip line runs parallel to and through the ring-shaped tubular path, with its coupling port connected to the signal transceiver. The ring-shaped tubular path couples the input signal to the microstrip line, generating a directional coupled signal. The microstrip line then transmits this signal back to the signal transceiver for power detection of the input signal. This design, by integrating the ring-shaped tubular path and the microstrip line within the PCB, enables the final PCB to function as a directional coupler, thus avoiding the need for separate fabrication or procurement from external suppliers when applying directional couplers to PCBs, reducing costs. Furthermore, the microstrip line structure in this embodiment is simple, directly penetrating the top and bottom layers of the PCB, avoiding signal loss problems caused by excessively long windings in traditional methods.
[0035] Reference Appendix Figure 2 The illustration shows a front view and a top view of an annular tubular passage provided in an embodiment of this application. Figure 2 As shown, the outer surface of the annular tubular passage is insulated, and the inner wall is a hollow coaxial line. Furthermore, an impedance path is attached to the inner wall of the annular tubular passage, wherein the linewidth of the impedance path is any value between 0.1 mm and 0.3 mm, and the characteristic impedance of the impedance path is any value between 50 ohms and 52 ohms.
[0036] Impedance paths are essentially radio frequency (RF) transmission lines. When the characteristic impedance of an RF transmission line is 51 ohms, energy transfer and signal matching between circuits are more efficient. In RF circuit design, maintaining matched impedances can reduce signal reflection and transmission loss, thereby improving system performance.
[0037] The linewidth of an RF transmission line refers to the width of its conductor or dielectric material. The choice of linewidth is closely related to design objectives because it determines the impedance characteristics of the transmission line. In a 50-ohm impedance design, a suitable linewidth is typically selected to match the standard 50-ohm impedance, based on the specific transmission line structure and the characteristics of the dielectric material. For example, in microstrip line design, factors such as linewidth, the dielectric constant of the dielectric material, and the dielectric layer thickness collectively determine the characteristic impedance of the transmission line. By adjusting the linewidth, the characteristic impedance of the transmission line can be made to achieve the required 50 ohms.
[0038] In one embodiment of this application, reference is made to the appendix. Figure 1 The isolation port S4 of the microstrip line 300 is located on the top layer of the printed circuit board, and the coupling port S3 is located on the bottom layer of the printed circuit board.
[0039] In one embodiment of this application, the microstrip line may be a fin-shaped microstrip line.
[0040] In one embodiment of this application, the width of the microstrip line is any value between 0.1 mm and 0.3 mm, and the distance between the outer surface of the microstrip line and the inner wall of the annular tubular passage is any value between 0.25 mm and 0.45 mm.
[0041] In this embodiment, the isolation port of the microstrip line is located on the top layer of the printed circuit board, while the coupling port is located on the bottom layer. This layered layout helps optimize the signal transmission path, reduce signal interference, and improve signal integrity. Simultaneously, the use of a finned microstrip line structure further enhances signal coupling efficiency and transmission stability. Furthermore, the width of the microstrip line is any value between 0.1 mm and 0.3 mm, and the distance between its outer surface and the inner wall of the annular tubular passage is any value between 0.25 mm and 0.45 mm. The precise design of these parameters effectively controls the characteristic impedance of the microstrip line, ensuring good matching characteristics during signal transmission, thereby reducing signal reflection and loss, and improving the performance and reliability of the entire directional coupling circuit.
[0042] This application also provides an electronic device, including the directional coupling circuit of any of the above embodiments.
[0043] In one embodiment of this application, the electronic device may be an inter-board ring directional coupler.
[0044] It should be noted that the above embodiments can be freely combined as needed. The above are merely preferred embodiments of this utility model. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.
Claims
1. A directional coupler, characterized by The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit.
2. The directional coupling circuit of claim 1, wherein, The application relates to a directional coupling circuit.
3. The directional coupling circuit of claim 1, wherein, The application relates to a directional coupling circuit.
4. The directional coupling circuit of claim 1, wherein, The application relates to a directional coupling circuit.
5. The directional coupling circuit of claim 1, wherein, The application relates to a directional coupling circuit.
6. The directional coupler of any one of claims 1-5, wherein, The application relates to a directional coupling circuit.
7. The directional coupler of any one of claims 1-5, wherein, The application relates to a directional coupling circuit.
8. The directional coupler of any one of claims 1-5, wherein, The application relates to a directional coupling circuit.
9. An electronic device, comprising: The application relates to a directional coupling circuit.
10. The electronic device of claim 9, wherein, The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. The application relates to a directional coupling circuit. 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