Electric tuning frequency hopping filter and communication equipment

Abstract

The utility model provides an electric tuning frequency hopping filter and communication equipment. The electric tuning frequency hopping filter comprises a first coupling structure, a second coupling structure, a first grounding bonding pad and a second grounding bonding pad which are arranged on a printed circuit laminated plate, wherein the first coupling structures are arranged on different layers of the printed circuit laminated board, and the second coupling structures are arranged on different layers of the printed circuit laminated board; a first interval is formed between the first end of the first coupling structure and the first grounding bonding pad, and the first end is electrically connected with the first grounding bonding pad through the first variable capacitor; a second interval is formed between the first end of the second coupling structure and the second grounding bonding pad, and the first end and the second grounding bonding pad are electrically connected through a second variable capacitor; the second end of the first coupling structure and the second end of the second coupling structure are respectively connected with a total grounding end; the first end of the first coupling structure and the first end of the second coupling structure are arranged on the topmost layer of the printed circuit laminated board, and the second end of the first coupling structure and the second end of the second coupling structure are arranged on the layer, except the topmost layer, of the printed circuit laminated board.

Description

Technical Field

[0001] The utility model relates to a filter and communication equipment, in particular to an electrically tuned frequency hopping filter. Background Art

[0002] An electrically tunable frequency-hopping filter (ETF) is a filter capable of rapidly changing its center frequency over a wide frequency range. It is primarily used in frequency-hopping communication systems. Frequency-hopping communication is an anti-interference and secure communication technology that transmits signals by rapidly and randomly hopping the carrier frequency across multiple preset frequencies to combat interference and eavesdropping. The ETF is a key component in implementing this technology, automatically adjusting its passband center frequency to match the currently used carrier frequency based on the frequency-hopping pattern.

[0003] Existing electrically tunable filters are typically implemented using varactor diodes and hand-wound inductors. These components, such as capacitors and inductors, filter out harmonic signals while transmitting the desired fundamental signal, ensuring proper circuit operation and improving the anti-interference capabilities of radio communication systems. However, these filters require manual tuning, suffer from poor reliability and consistency, and have a fixed structure, making them unsuitable for certain specific needs. Utility Model Content

[0004] In view of the defects of the prior art, the utility model successfully develops an electrically tuned frequency hopping filter.

[0005] On one hand, the utility model provides an electrically tuned frequency hopping filter, comprising: a first variable capacitor, a second variable capacitor, and an input end, an input inductor, a first coupling structure, a second coupling structure, an output inductor, a first grounding pad, a second grounding pad, and an output end arranged on a printed circuit laminate; wherein the first coupling structure is arranged on a different layer of the printed circuit laminate, and the second coupling structure is arranged on a different layer of the printed circuit laminate; a first gap is provided between the first end of the first coupling structure and the first grounding pad, and the two are electrically connected through the first variable capacitor; a second gap is provided between the first end of the second coupling structure and the second grounding pad, and the two are electrically connected through the second variable capacitor; the second end of the first coupling structure and the second end of the second coupling structure are respectively connected to a main ground end; the first end of the first coupling structure and the first end of the second coupling structure are arranged on the topmost layer of the printed circuit laminate, and the second end of the first coupling structure and the second end of the second coupling structure are arranged on a layer other than the topmost layer of the printed circuit laminate.

[0006] Furthermore, the connection between the input inductor and the first coupling structure and the first end of the first coupling structure constitutes the first portion of the first coupling structure, and the connection between the input inductor and the first coupling structure and the second end of the first coupling structure constitutes the second portion of the first coupling structure. The second coupling structure is physically connected to the output inductor, the connection between the output inductor and the first coupling structure and the first end of the first coupling structure constitutes the first portion of the first coupling structure, and the connection between the input inductor and the first coupling structure and the second end of the first coupling structure constitutes the second portion of the first coupling structure.

[0007] Furthermore, the first variable capacitor or the second variable capacitor is a patch variable capacitor, and the first coupling structure and the second coupling structure include microstrip lines.

[0008] Furthermore, the first variable capacitor or the second variable capacitor is a controlled varactor diode or a controlled varactor transistor.

[0009] Furthermore, the first coupling structure includes a first coil spirally wound on different metal layers of the printed circuit laminate; the second coupling structure includes a second coil spirally wound on different metal layers of the printed circuit laminate, the first coil is electrically connected between sub-coils on different metal layers of the printed circuit laminate through conductive vias; the second coil is electrically connected between sub-coils on different metal layers of the printed circuit laminate through conductive vias.

[0010] Furthermore, the closest distance between the sub-coils of the first coil on different metal layers of the printed circuit board and the sub-coils of the second coil on corresponding metal layers of the printed circuit board varies nonlinearly.

[0011] Furthermore, the distance between the sub-coil at the near-ground end of the first coil and the sub-coil at the near-ground end of the second coil is greater than the distance between the sub-coil at the far-ground end of the first coil and the sub-coil at the far-ground end of the second coil.

[0012] Furthermore, a main ground terminal is provided in a direction orthogonal to the input terminal and the output terminal.

[0013] Furthermore, a ground terminal for shielding is provided in a direction parallel to the input terminal and the output terminal.

[0014] Another aspect of the present invention provides a communication device, comprising any one of the aforementioned filters.

[0015] The beneficial effects of this utility model are as follows: the filter of this utility model utilizes the laminated structure of the PCB board, integrating the parts that require manual adjustment directly into the interior and surface of the PCB, greatly reducing working hours, improving production efficiency, and enhancing product consistency and reliability. Moreover, due to the fixed structure, it can meet certain specific requirements. Within the frequency hopping range, the filter of this utility model can increase the relative bandwidth as the center frequency increases. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following description of the present invention will provide a more comprehensive understanding of the above and other purposes, features, and advantages of the present invention, with reference to the accompanying drawings. The accompanying drawings are intended only to illustrate the principles of the present invention. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale.

[0017] Figure 1A A three-dimensional schematic diagram of an electrically tuned frequency hopping filter of the present invention is shown;

[0018] Figure 1B A top view of the electrically tuned frequency hopping filter of the present invention is shown;

[0019] Figure 1C Shows a left side view of the electrically tuned frequency hopping filter of the present invention;

[0020] Figure 2A 1 GHz bandwidth diagram of the electrically tunable frequency hopping filter in Example 1;

[0021] Figure 2B is a bandwidth diagram of the electrically tunable frequency hopping filter at 1.5 GHz in Example 1;

[0022] Figure 2C FIG. 4 is a bandwidth diagram of the electrically tunable frequency hopping filter in Example 1 at 2 GHz. DETAILED DESCRIPTION

[0023] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, the following detailed description of specific embodiments of the present invention is provided in conjunction with the accompanying drawings, so that the above-mentioned and other objects, features, and advantages of the present invention will become more apparent. Like reference numerals denote like parts throughout the drawings. The drawings are not drawn to scale; emphasis is placed on illustrating the subject matter of the present invention.

[0024] The terms and words used in the following description and claims are not limited to the bibliographical meanings, but are merely used by the inventor to enable a clear and consistent understanding of the present invention. Therefore, it will be apparent to those skilled in the art that the following description of various embodiments of the present invention is provided for illustration purposes only and not for the purpose of limiting the present invention as defined by the appended claims and their equivalents.

[0025] It is to be understood that the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to "a module" includes reference to one or more of such modules. The advantages and features of the present application will become apparent from the detailed description of the embodiments given below, and the accompanying drawings. The present application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the application to those skilled in the art.

[0026] Referring to Figure 1A-1C , Figure 1A Fig. 1 shows a perspective view of the electrically tunable frequency hopping filter of the present application, Figure 1B Fig. 2 shows a top view of the electrically tunable frequency hopping filter of the present application; Figure 1C Fig. 3 shows a left view of the electrically tunable frequency hopping filter of the present application. The electrically tunable frequency hopping filter of the present embodiment comprises at least an input terminal RFIN, an input inductor 3, a first coupling structure 1, a second coupling structure 2, an output inductor 4 and an output terminal RFOUT, which are arranged in a printed circuit board compatible manner. The first coupling structure 1 and the second coupling structure 2 are arranged symmetrically on the printed circuit board. The input terminal RFIN of the filter is connected to the first coupling structure 1 through the input inductor 3, and the output terminal RFOUT of the filter is connected to the second coupling structure 2 through the output inductor 4. Figure 1A-1B In the present embodiment, the first coupling structure 1 is arranged on the left side of the printed circuit board, and the second coupling structure 2 is arranged on the right side of the printed circuit board. The first coupling structure 1 and the second coupling structure 2 are arranged symmetrically on the printed circuit board. The input terminal RFIN of the filter is connected to the first coupling structure 1 through the input inductor 3, and the output terminal RFOUT of the filter is connected to the second coupling structure 2 through the output inductor 4.

[0027] In an exemplary embodiment, the printed circuit board of the present application can use Rogers 4350B board material with a thickness of about 0.2-1.2 mm.

[0028] Further, the input inductor 3 and the output inductor 4 have an inductance of 0.5-100 nH, and the wiring width on the printed circuit board is 0.05-0.6 mm and the length is 0.5-10 mm. It can be understood that the input inductor 3 and the output inductor 4 can also be arranged on the printed circuit board in the form of a patch inductor.

[0029] The first coupling structure 1 and the second coupling structure 2 can use microstrip lines or striplines. The specific selection of microstrip lines and striplines depends on the needs of the specific application, including comprehensive consideration of factors such as operating frequency, cost budget, space constraints, signal integrity and shielding requirements. Based on the structural characteristics of microstrip lines and striplines, they can be well compatible with printed circuit laminates, so that parts that originally required manual debugging can be directly integrated into the interior or surface of the printed circuit laminate. Microstrip lines or striplines are preferably gold wires, silver wires or copper wires. This approach greatly shortens working hours, improves production efficiency, and enhances product consistency and reliability. It should be understood that although the first coupling structure 1 and the second coupling structure 2 are implemented in the form of inductors in this specific embodiment through metal strips, it is sufficient for the first coupling structure and the second coupling structure to generate a coupling function. Therefore, in addition to being in the form of inductors, the first coupling structure and the second coupling structure can also be other structures, such as resonators.

[0030] Specifically, the first ground pad 11 is formed on the topmost layer of the printed circuit laminate and connected to the general ground terminal GND of the printed circuit laminate. The general ground terminal GND of the printed circuit laminate is formed in a direction orthogonal to the input terminals RFIN and RFOUT.

[0031] The first coupling structure 1 includes a first microstrip line 12. The first microstrip line 12 can be formed by first coils formed in spirals on different layers of a printed circuit laminate. The coils on different layers are electrically connected through conductive vias. The first end of the first microstrip line 12 is formed on the top layer of the printed circuit laminate. The second end of the first microstrip line 12 is formed on the top layer of the printed circuit laminate. Figure 1C As shown, it is formed on the third layer of the printed circuit laminate. It can be understood that the second end of the first microstrip line 12 can be formed on other layers except the top layer according to the winding length of the first coil. There is a first gap 13 between the first ground pad 11 and the first microstrip line 12, and a first variable capacitor (not shown in the figure) is connected to the first gap 13. The first variable capacitor can be a chip capacitor in any form, such as a varactor diode, a varactor transistor, etc. The second end of the first microstrip line 12 is also connected to the main ground terminal GND of the printed circuit laminate. The first microstrip line 12 can be formed in various shapes on the printed circuit laminate.

[0032] The first ground pad 21 is formed on the topmost layer of the printed circuit laminate and is connected to the general ground terminal GND of the printed circuit laminate. The general ground terminal GND of the printed circuit laminate is formed in a direction orthogonal to the input terminals RFIN and RFOUT.

[0033] The second coupling structure 2 comprises a second microstrip line 22, which can be formed by a spiral coil on different layers of the printed circuit laminated board and electrically connected through conductive vias between the coils on different layers. The first end of the second microstrip line 22 is formed on the top layer of the printed circuit laminated board, and the second end of the second microstrip line 22 is formed on the third layer of the printed circuit laminated board. It can be understood that the second end of the second microstrip line 22 can be formed on other layers except the top layer according to the length of the second coil. The second variable capacitor (not shown in the figure) is connected on the second interval 23 between the second ground pad 21 and the second microstrip line 22. The second variable capacitor can be any form of patch capacitor, such as varactor diode, varactor triode, etc. The second end of the second microstrip line 22 is also connected with the total ground end GND of the printed circuit laminated board. The second microstrip line 22 can form various shapes on the printed circuit laminated board. For example, the second microstrip line 22 can be formed in a spiral shape as shown in FIG. 1.

[0034] Through the above layout, the third interval is formed between the first end of the first microstrip line 12 and the first end of the second microstrip line 22, and the fourth interval is formed between the second end of the first microstrip line 12 and the second end of the second microstrip line 22. For example, the width of the third interval is smaller than the width of the fourth interval.

[0035] Further, the closest interval between the sub-coils of the first coil on different metal layers of the printed circuit board and the sub-coils of the second coil on corresponding metal layers of the printed circuit board is nonlinearly changed. More specifically, the interval between the sub-coils of the first coil and the second coil near the ground end is greater than the interval between the sub-coils of the first coil and the second coil far from the ground end.

[0036] In the utility model, signal enters from the input end RFIN of filter, passes through input inductance 3, is transmitted to first coupling structure 1 through physical connection, then signal is coupled to second coupling structure 2 through first coupling structure 1, and is output from output end RFOUT again through output inductance 4. The first end of first coupling structure 1 is connected to first ground pad 12 through first variable capacitor and then grounded, the second end of first coupling structure 1 is grounded, the first end of second coupling structure 2 is connected to second ground pad 22 through second variable capacitor and then grounded, and the second end of second coupling structure 2 is grounded. The first variable capacitor and the second variable capacitor can be controllable varactor diode, the capacitance value of the varactor diode can be changed through the control circuit, and the specific structure of the control circuit can be any structure that can realize the above specific control function, which is not limited. The control circuit can also be arranged on the PCB board, and the part originally needing manual debugging can be directly integrated into the interior or surface of the printed circuit board.

[0037] By adjusting the capacitance value of the first variable capacitor and / or the second variable capacitor, the bandwidth of the filter can be adjusted, for example by selecting different types of varactor diodes, thereby having different capacitance variation ranges, or by adjusting the capacitance value of the varactor diodes. In addition to adjusting the capacitance value, the input inductor 3 and the output inductor 4 also have a significant effect on the signal, so that by adjusting the input inductor 3 and the output inductor 4, more flexible and more extensive signal processing can be achieved.

[0038] In addition, in the utility model, the first end of the first coupling structure to the connection with the input inductor, and the first end of the second coupling structure to the connection with the output inductor can be regarded as an electric part, the connection of the first coupling structure with the input inductor to the second end, and the connection of the second coupling structure with the output inductor to the second end can be regarded as a magnetic part, the interval of the magnetic part is smaller, the relative bandwidth is larger, the interval of the magnetic part is larger, the relative bandwidth is smaller. Thus, the relative distance between the microstrip line or the strip line can be adjusted to adjust the bandwidth.

[0039] The above structure can realize a frequency hopping filter in which the relative bandwidth (for example, can increase from 5% to 6%, or decrease from 10% to 15%) increases with the increase of the center frequency in different frequency ranges (for example, can be realized in 500-1500MHz, 1000-2000MHz, etc.).

[0040] The filter of the utility model is tested, as shown in the figure, Figure 2A At 1GHz, the 3dB bandwidth is about 136MHz, and the relative bandwidth is 13.6%; at 1.5GHz, as shown in the figure, Figure 2B The 3dB bandwidth is about 224MHz, and the relative bandwidth is 14.9%; as shown in the figure, Figure 2C At 2GHz, the 3dB bandwidth is about 332MHz, and the relative bandwidth is 16.6%.

[0041] As can be seen, the electrically tunable frequency hopping filter of the utility model, in the frequency hopping range covered by the filter, the relative bandwidth decreases from 13.6% to 16.6% when the center frequency changes from 1GHz to 2GHz.

[0042] Further, in the embodiment, a ground end SGND as shown in the figure can be arranged on both sides of the input end RFIN and both sides of the output end RFOUT respectively, and the ground end SGND can be used for shielding.

[0043] Further, the electrically tunable frequency hopping filter of the utility model can be used in electronic equipment, and the electronic equipment can be a desktop computer, a notebook computer, a smart phone, a smart watch, a wearable device, an Internet server smart voice system, a router, a car electronic device, an Internet of Things (IoT) device, a medical device, etc.

[0044] Although the technology has been illustrated and described with respect to one or more embodiments, changes and / or modifications may be made to the illustrated examples without departing from the spirit and scope of the appended claims. In particular, with respect to the various functions performed by the components or structures (assemblies, devices, circuits, systems, etc.) described above, terms used to describe such components (including references to "means") are intended to correspond to any component or structure that performs the designated function of the described component (e.g., functionally equivalent), even if not structurally equivalent to the disclosed structure that performs the function in the example embodiments described herein, unless otherwise indicated. In addition, although a particular feature may have been disclosed with respect to one embodiment among several embodiments, such feature may be combined with one or more other features in other embodiments as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms "comprising," "including," "having," "having," "containing," or variations thereof are used in the detailed description or claims, such terms are intended to be inclusive in a manner similar to the term "comprising."

[0045] In the above description, many specific details are set forth in order to fully understand the present invention. However, the above description is only a preferred embodiment of the present invention. The present invention can be implemented in many other ways different from those described herein, so the present invention is not limited by the specific implementation disclosed above. At the same time, any person skilled in the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present invention without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. An electrically tuned frequency hopping filter, characterized in that: include: A first variable capacitor, a second variable capacitor, and an input terminal, an input inductor, a first coupling structure, a second coupling structure, an output inductor, a first ground pad, a second ground pad, and an output terminal are provided on the printed circuit laminate; wherein the first coupling structure is provided on a different layer of the printed circuit laminate, and the second coupling structure is provided on a different layer of the printed circuit laminate; A first end of the first coupling structure and the first ground pad are electrically connected with each other via a first variable capacitor with a first spacing therebetween; A second gap is formed between the first end of the second coupling structure and the second ground pad, and the two are electrically connected via a second variable capacitor; the second end of the first coupling structure and the second end of the second coupling structure are respectively connected to the main ground terminal; The first end of the first coupling structure and the first end of the second coupling structure are arranged on the top layer of the printed circuit laminate, and the second end of the first coupling structure and the second end of the second coupling structure are arranged on a layer other than the top layer of the printed circuit laminate.

2. The filter according to claim 1, wherein: The connection point between the input inductor and the first coupling structure and the first end of the first coupling structure is the first part of the first coupling structure, and the connection point between the input inductor and the first coupling structure and the second end of the first coupling structure is the second part of the first coupling structure; The second coupling structure is physically connected to the output inductor. The connection between the output inductor and the first coupling structure and the first end of the first coupling structure constitutes the first part of the first coupling structure. The connection between the input inductor and the first coupling structure and the second end of the first coupling structure constitutes the second part of the first coupling structure.

3. The filter according to claim 2, wherein: The first variable capacitor or the second variable capacitor is a patch variable capacitor, and the first coupling structure and the second coupling structure include microstrip lines.

4. The filter according to claim 3, wherein: The first variable capacitor or the second variable capacitor is a controlled varactor diode or a controlled varactor transistor.

5. The filter according to any one of claims 1 to 4, characterized in that: The first coupling structure includes a first coil spirally wound on different metal layers of a printed circuit laminate; the second coupling structure includes a second coil spirally wound on different metal layers of the printed circuit laminate, the first coil is electrically connected between sub-coils on different metal layers of the printed circuit laminate through conductive vias; the second coil is electrically connected between sub-coils on different metal layers of the printed circuit laminate through conductive vias.

6. The filter according to claim 5, wherein: The closest distance between the sub-coils of the first coil on different metal layers of the printed circuit board and the sub-coils of the second coil on corresponding metal layers of the printed circuit board varies nonlinearly.

7. The filter according to claim 6, wherein: The distance between the sub-coil at the near-ground end of the first coil and the sub-coil at the near-ground end of the second coil is greater than the distance between the sub-coil at the far-ground end of the first coil and the sub-coil at the far-ground end of the second coil.

8. The filter according to claim 7, wherein: A main ground terminal is provided in a direction orthogonal to the input terminal and the output terminal.

9. The filter according to claim 8, wherein: A ground terminal for shielding is provided in a direction parallel to the input terminal and the output terminal.

10. A communication device, characterized in that: A filter comprising the filter of any one of claims 1-9.

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