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 variable capacitor, a second variable capacitor, and an input end, an input inductor, a first coupler, a first bonding pad, a second coupler, an output inductor, a second bonding pad and an output end which are arranged on a printed circuit board, wherein the first coupler is provided with a first part and a second part, and the second coupler is provided with a first part and a second part; a first gap is formed between the first part of the first coupler and the first bonding pad, and the first part and the first bonding pad are electrically connected through the first variable capacitor; a second interval is formed between the first part of the second coupler and the second bonding pad, and the first part and the second bonding pad are electrically connected through a second variable capacitor; the distance between the first coupler and the second coupler is constant.

Description

Technical Field

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

[0002] An electrically tunable frequency hopping filter is a filter that can quickly change its center frequency within a relatively wide frequency range, and is mainly used in frequency hopping communication systems. Frequency hopping communication is an anti-jamming and secure communication technology that transmits signals by quickly and randomly hopping the carrier frequency among multiple preset frequencies to combat interference and eavesdropping. The electrically tunable frequency hopping filter is one of the key components to realize this technology, and it can automatically adjust the center frequency of its passband according to the frequency hopping pattern to match the currently used carrier frequency.

[0003] Existing electrically tunable filters usually use varactor diodes and hand-wound inductors to achieve. Harmonic signals are filtered out through components such as capacitors and inductors, and the required fundamental signals are transmitted, thus ensuring the normal operation of the circuit and helping the radio communication system improve its anti-jamming ability. Since this kind of filter requires manual debugging, its reliability and consistency are poor, and its structure is fixed, which cannot meet some specific requirements. Summary of the Utility Model

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

[0005] The utility model provides an electrically tunable frequency hopping filter on the one hand, including: a first variable capacitor, a second variable capacitor, an input terminal, an input inductor, a first coupler, a first pad, a second coupler, an output inductor, a second pad, and an output terminal arranged on a printed circuit board; wherein the first coupler has a first part and a second part, and the second coupler has a first part and a second part; there is a first gap between the first part of the first coupler and the first pad and they are electrically connected through the first variable capacitor; there is a second gap between the first part of the second coupler and the second pad and they are electrically connected through the second variable capacitor; the distance between the first coupler and the second coupler is constant.

[0006] Further, the input inductor is physically connected to the first coupler, and the connection point serves as the boundary between the first part and the second part of the first coupler; the second coupler is physically connected to the output inductor, and the connection point serves as the boundary between the first part and the second part of the second coupler.

[0007] Further, the first variable capacitor or the second variable capacitor is a surface mount variable capacitor.

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

[0009] Further, the first variable capacitor or the second variable capacitor is a controlled varactor diode, and the capacitance value variation range of the controlled varactor diode is from 0.05 to 10 pF.

[0010] Further, the shapes of the first coupler and the second coupler are equidistant arc-shaped, strip-shaped extending in the vertical direction, or strip-shaped inclined with respect to the horizontal direction.

[0011] Further, the inductance values of the input inductor and the output inductor are from 0.5 to 100 nH, the wiring width is from 0.05 to 0.6 mm, and the length is from 0.5 to 10 mm.

[0012] Further, the first coupler and the second coupler are strip-shaped extending in the vertical direction, and the width of the strip is set to be from 0.1 to 2 mm, and the length of the first strip is from 0.5 to 10 mm.

[0013] Further, the distance between the first coupler and the second coupler is from 0.1 to 4 mm.

[0014] On the other hand, the present utility model provides a communication device, including the filter according to any one of the foregoing.

[0015] The beneficial effects of the present utility model are as follows: The filter of the present utility model adopts microstrip line technology, which greatly improves the reliability and consistency of the product, has high production efficiency, and has a fixed structure; Since the filter of the present utility model ensures that the distances formed between all parts of the first coupler and all parts of the second coupler are the same, a relatively stable bandwidth can be guaranteed within the hopping frequency range. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The specific content of the present utility model will be described below with reference to the accompanying drawings, which will help to more easily understand the above and other objects, features, and advantages of the present utility model. The drawings are only for showing the principle of the present utility model. The dimensions and relative positions of the units do not have to be drawn to scale in the drawings.

[0017] Figure 1 is a schematic structural diagram of the electrically tunable frequency modulation filter in Embodiment 1;

[0018] Figure 2A is the bandwidth diagram of the electrically tunable frequency modulation filter in Embodiment 1 at 1 GHz;

[0019] Figure 2B is the bandwidth diagram of the electrically tunable frequency modulation filter in Embodiment 1 at 1.5 GHz;

[0020] Figure 2C is the bandwidth diagram of the electrically tunable frequency modulation filter in Embodiment 1 at 2 GHz. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] To make the above objects, features, and advantages of the present utility model more apparent and understandable, the following detailed description of the specific embodiments of the present utility model will be provided in conjunction with the accompanying drawings, making the above and other objects, features, and advantages of the present utility model clearer. The same reference numerals in all the drawings indicate the same parts. The drawings are not deliberately drawn to scale, and the emphasis is on showing the gist of the present utility model.

[0022] The terms and words used in the following description and claims are not limited to their written meanings, but are only used by the inventor to clearly and consistently understand the present utility model. Therefore, it is obvious to those skilled in the art that the following description of the various embodiments of the present utility model is for illustrative purposes only and not for the purpose of limiting the present utility model defined by the appended claims and their equivalents.

[0023] It should be understood that the singular forms "a", "an", and "the" include plural objects unless the context clearly dictates otherwise. Thus, for example, reference to "a module" includes reference to one or more such modules. The advantages and features of the present utility model and the method of implementing the present utility model can be more easily understood by referring to the detailed description of the following embodiments and the accompanying drawings. However, the present utility model can 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 the present utility model will be thorough and complete and will fully convey the concept of the present utility model to those skilled in the art.

[0024] Please refer to Figure 1 , Figure 1 which shows a specific embodiment of the electronically tunable frequency hopping filter of the present utility model. The electronically tunable frequency hopping filter of this embodiment includes an input end RFIN, an input inductor 3, a first coupler 1, a first pad 11, a second coupler 2, an output inductor 4, a second pad 21, and an output end RFOUT, which are provided on one layer of the multi-layer metal of a printed circuit board (PCB). As Figure 1 shown, the first coupler 1 is disposed on the left side and the second coupler 2 is disposed on the right side. The input end RFIN of the filter is connected to the first coupler 1 through the input inductor 3, and the output end RFOUT of the filter is connected to the second coupler 2 through the output inductor 4.

[0025] Exemplarily, the printed circuit board in the present utility model can use Rogers4350B board with a thickness of about 0.2 - 1.2 mm.

[0026] Further, the inductance values of the input inductor 3 and the output inductor 4 are 0.5 - 100 nH, and their wiring widths on the printed circuit board are 0.05 - 0.6 mm, and the lengths are 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 surface mount inductors. The shapes of the first coupler 1 and the second coupler 2 can be arcs arranged at equal intervals, bars extending in the vertical direction, or bars arranged obliquely with respect to the horizontal direction. Preferably, the shapes of both the first coupler 1 and the second coupler 2 are bars, the width of the bar can be set to 0.1 - 2 mm, and the bar lengths of the first coupler 1 and the second coupler 2 are 0.5 - 10 mm. In the present invention, it is necessary to ensure that the distances formed between all parts of the first coupler 1 and all parts of the second coupler 2 are the same, that is, to make the distance between the first coupler 1 and the second coupler 2 constant. Exemplarily, the distance between the first coupler 1 and the second coupler 2 is 0.1 - 4 mm. It should be understood that although the first coupler and the second coupler are presented in the form of inductors by means of metal strips in this specific embodiment, as long as the first coupler and the second coupler can generate a coupling function, so the first coupler and the second coupler can be other structures in addition to being presented in the form of inductors, such as resonators.

[0027] Among them, the first coupler 1 and the second coupler 2 can use microstrip lines or stripline. The specific selection of microstrip lines and stripline depends on the requirements of specific applications, including factors such as operating frequency, cost budget, space limitations, signal integrity, and shielding requirements for comprehensive consideration. Based on the structural characteristics of microstrip lines and stripline, they can be well compatible with the printed circuit board (PCB board). The microstrip line or stripline is preferably made of gold wire, silver wire or copper wire. Adopting this method greatly shortens the working hours, improves the production efficiency, and enhances the consistency and reliability of the product.

[0028] Specifically, the first coupler 1 has a first part and a second part. The first part of the first coupler 1 includes the first microstrip line 15 of the first coupler 1. The second part of the first coupler 1 includes the second microstrip line 12 of the first coupler 1. The first microstrip line 15 and the second microstrip line 12 are demarcated at the connection between the input inductor 3 and the first coupler 1. The input inductor 3 is directly physically connected to the first coupler 1. The first pad 11 is connected to the ground via hole 13. The second end of the second microstrip line 12 of the first coupler 1, which is far from the first pad 11, is connected to the ground. A first gap 14 is formed between the first pad 11 and the first microstrip line 15 of the first coupler 1. A first variable capacitor (not shown in the figure) is connected across the first gap. The first variable capacitor can be any form of surface mount capacitor, such as varactor diodes, varactor triodes, etc.

[0029] The second coupler 2 has a first part and a second part, wherein the first part of the second coupler 2 includes the first microstrip line 25 of the second coupler 2. The second part of the second coupler 2 includes the second microstrip line 22 of the second coupler 2. The connection between the first microstrip line 25 and the second microstrip line 22 is demarcated at the connection of the output inductor 4 and the second coupler 2. The output inductor 4 is directly physically connected to the second coupler 2. The second pad 21 is connected to the ground via hole 23. The second end of the second microstrip line 22 of the first coupler 2, which is away from the second pad 21, is grounded to the second coupler 2. A second gap 24 is formed between the second pad 21 and the second microstrip line 22 of the second coupler 2. A second variable capacitor (not shown in the figure) is connected across the second gap 24. The second variable capacitor can be any form of variable capacitor, such as a varactor diode, a varactor triode, etc. Further, the varactor diode is a controllable varactor diode, and the capacitance value of the varactor diode can be changed through a control circuit. The specific structure of the control circuit can be any structure that can achieve the above specific control functions, and no specific limitation is imposed on it. The control circuit can also be disposed on the PCB board, so that the part that originally needed manual debugging can be directly integrated into the interior or surface of the PCB board.

[0030] In the present utility model, a signal enters from the input end RFIN of the filter, passes through the input inductor 3, and then is transmitted to the first coupler 1. The signal is coupled by the first coupler 1 to the second coupler 2, and then is output from the output end RFOUT through the output inductor 4.

[0031] By adjusting the capacitance values of the first variable capacitor 13 and / or the second variable capacitor 23, the bandwidth of the filter can be adjusted. For example, by selecting varactor diodes of different models, which have different capacitance change ranges. Exemplarily, the capacitance value change range of the varactor diode is between 0.05 - 10 pF. Or by adjusting the capacitance value of the varactor diode. In addition to adjusting the capacitance value, the input inductor 3 and the output inductor 4 also have a significant impact on the signal. Therefore, by adjusting the input inductor 3 and the output inductor 4, more flexible and broader signal processing can be achieved.

[0032] In the present utility model, the first microstrip line 15 of the first coupler and the first microstrip line 25 of the second coupler can be regarded as the electrical part, and the second microstrip line 12 of the first coupler and the second microstrip line 22 of the second coupler can be regarded as the magnetic part. When the distance between the magnetic parts becomes smaller, the relative bandwidth becomes larger; when the distance between the magnetic parts becomes larger, the relative bandwidth becomes smaller. The bandwidth can be adjusted by adjusting the relative distance between the microstrip lines or the strip lines. In the present utility model, since it is ensured that the distances formed between all parts of the first coupler 1 and all parts of the second coupler 2 are the same, a structure can be obtained in which the relative bandwidth can be guaranteed to be stable within the frequency hopping range.

[0033] The filter of the present utility model is tested asFigure 2A As shown, at 1 GHz, the 3 dB bandwidth is approximately 100 MHz, and the relative bandwidth is 10%; at 1.5 GHz, as Figure 2B shown, the 3 dB bandwidth is approximately 150 MHz, and the relative bandwidth is 10%; as Figure 2C shown, at 2 GHz, the 3 dB bandwidth is approximately 200 MHz, and the relative bandwidth is 10%.

[0034] It can be seen that for the electronically tunable frequency hopping filter of the present utility model, within the frequency hopping range covered by the filter, as the center frequency varies from 1 GHz to 2 GHz, the relative bandwidth does not change with the center frequency of the filter, ensuring that the bandwidth throughout the frequency hopping range is 10%, providing an electronically tunable frequency modulation filter capable of maintaining a stable relative bandwidth within the frequency modulation range.

[0035] In addition, in the present utility model, the use of microstrip lines or strip lines is more convenient for design on the same layer of the PCB board, facilitating the improvement of production efficiency.

[0036] Furthermore, the electronically tunable frequency modulation filter disclosed herein can be used in electronic devices, which can be desktop computers, laptops, smart phones, smart watches, wearable devices, Internet server intelligent voice systems, routers, automotive electronic devices, Internet of Things (IoT) devices, medical devices, etc.

[0037] Although the technology has been described and illustrated with respect to one or more embodiments, changes and / or modifications can 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 above-described components or structures (components, devices, circuits, systems, etc.), the terms used to describe such components (including references to "means") are intended to correspond to any component or structure that performs the specified function of the described component (e.g., functionally equivalent), even if not structurally equivalent to the disclosed structure that performs the functions in the exemplary embodiments described herein, unless otherwise specified. Additionally, although a particular feature may have been disclosed with respect to one of several embodiments, such a feature can be combined with one or more other features in one or more other embodiments as may be desired and advantageous for any given or particular application. Moreover, with respect to the use of the terms "comprises," "comprising," "includes," "including," "has," "having," "contains," or variations thereof in the detailed description or claims, such terms are intended to be inclusive in a manner similar to the term "including."

[0038] In the above description, many specific details are set forth to facilitate a full understanding of the present utility model. However, the above description is only a preferred embodiment of the present utility model, and the present utility model can be implemented in many other ways different from those described herein. Therefore, the present utility model is not limited by the specific implementations disclosed above. At the same time, any person skilled in the art can make many possible changes and modifications to the technical solution of the present utility model by using the methods and technical content disclosed above without departing from the scope of the technical solution of the present utility model, or modify it into an equivalent embodiment with equivalent changes. All those that do not depart from the content of the technical solution of the present utility model, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present utility model still fall within the scope of protection of the technical solution of the present utility model.

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 coupler, a first pad, a second coupler, an output inductor, a second pad, and an output terminal arranged on a printed circuit board; wherein the first coupler has a first portion and a second portion, and the second coupler has a first portion and a second portion; The first portion of the first coupler and the first pad have a first spacing therebetween and are electrically connected via a first variable capacitor; The first portion of the second coupler and the second pad have a second interval therebetween and are electrically connected via a second variable capacitor; The distance between the first coupler and the second coupler is constant.

2. The filter according to claim 1, characterized in that: The input inductor is physically connected to the first coupler and the connection point serves as the boundary between the first part and the second part of the first coupler; the second coupler is physically connected to the output inductor and the connection point serves as the boundary between the first part and the second part of the second coupler.

3. The filter according to claim 2, characterized in that: The first variable capacitor or the second variable capacitor is a chip variable capacitor.

4. The filter according to claim 3, characterized in that: The first variable capacitor or the second variable capacitor is a controlled variable capacitance diode or a controlled variable capacitance transistor.

5. The filter according to claim 4, characterized in that: The first variable capacitor or the second variable capacitor is a controlled variable capacitance diode, and the capacitance value of the controlled variable capacitance diode varies in the range of 0.05-10 pF.

6. The filter according to any one of claims 1 to 5, characterized in that: The first coupler and the second coupler are in the shape of equidistant arcs, bars extending in the vertical direction, or bars arranged obliquely with respect to the horizontal direction.

7. The filter according to claim 5, characterized in that: The inductance of the input inductor and the output inductor is 0.5-100nH, the wiring width is 0.05-0.6mm, and the length is 0.5-10mm.

8. The filter according to claim 7, characterized in that: The first coupler and the second coupler are in the shape of bars extending in the vertical direction, and the width of the bars is set to 0.1-2 mm, and the length of the first bar is 0.5-10 mm.

9. The filter according to claim 8, characterized in that: The spacing between the first coupler and the second coupler is 0.1-4 mm.

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

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