Single-ended to differential output non-standard balun and double-oscillator differential antenna

Abstract

The invention provides a single-ended to differential output nonstandard balun and a double-oscillator differential antenna, the nonstandard balun is a three-port component formed by a first conductor and a second conductor which are mutually coupled, and the nonstandard balun is correspondingly provided with an unbalanced port and two balanced ports in a grounding state, wherein the physical length corresponding to the one-time wavelength electrical length of the first conductor and the second conductor is defined as L, the two balance ports are located at the same end of the non-standard balun, and the distance between the two ends of the corresponding conductor with the balance ports is smaller than or equal to 3L / 16. When a single-ended signal in an unbalanced state is accessed to the unbalanced port of the non-standard balun, the signals output by the two balanced ports are opposite in phase within an error range of + / -30 degrees, namely, the difference between the signals output by the two balanced ports is larger than or equal to 150 degrees and smaller than or equal to 210 degrees, and the non-standard balun has a single-ended to differential output characteristic.

Description

Technical Field

[0001] The present invention relates to the field of microwave detection based on the Doppler effect principle, and in particular to a non-standard balun and a dual-dipole differential antenna suitable for microwave detection with single-ended to differential output. Background Art

[0002] With the development of Internet of Things technology, artificial intelligence, smart home, and smart security technology have higher and higher requirements for environmental detection, especially for the detection accuracy of human presence, movement, and micro-motion characteristics. Only by obtaining sufficiently stable detection results can we provide accurate judgment basis for smart terminal devices. Among them, microwave detection technology based on the principle of Doppler effect, as an important hub connecting people and objects, objects and objects, has unique advantages in behavior detection and existence detection technology. It can detect active objects without infringing on human privacy, such as human motion characteristics, movement characteristics, and micro-motion characteristics, and even human heartbeat and breathing characteristics information, so it has broad application prospects. Specifically, the corresponding microwave detector is fed by an excitation signal and transmits a microwave beam with a frequency corresponding to the excitation signal to the target space through the corresponding antenna, thereby forming a detection area in the target space, and receiving a reflected echo formed by the microwave beam being reflected by the corresponding object in the detection area and transmitting an echo signal corresponding to the frequency of the reflected echo to a mixing and detection unit, wherein the mixing and detection unit mixes the excitation signal and the echo signal and outputs a Doppler intermediate frequency signal corresponding to the frequency / phase difference between the excitation signal and the echo signal, wherein based on the principle of the Doppler effect, when the object reflecting the microwave beam is in motion, there is a certain frequency / phase difference between the echo signal and the excitation signal and the Doppler intermediate frequency signal presents corresponding amplitude fluctuations to feedback human activities. The antenna is the core component of the microwave detector, and its structural features and performance features associated with the structural features directly affect the structural design and performance parameters of the microwave detector. In particular, in the current industry situation where the microwave detector is mostly used as a functional module of a corresponding product (such as a lamp) and is required to adapt to the structure and use environment of the product, the structural features and performance features of the antenna directly affect the applicability of the microwave detector to the corresponding product. Under the trend of miniaturized structure of products and the current situation of increasingly dense electromagnetic radiation interference in the use environment of products, in order to achieve the adaptation of the microwave detector to the structure and use environment of the corresponding product, the microwave detector has increasingly stringent requirements on the structural features of the corresponding antenna and the performance features associated with the structural features.

[0003] Specifically, the antenna of the existing microwave detector has a reference ground based on the need for directional radiation, and most of them use unbalanced antennas fed by single-end feeding, such as traditional flat antennas (also called patch antennas) and cylindrical antennas. Therefore, there is an increasingly dense electromagnetic radiation interference in the use environment of the corresponding products. The microwave detector based on the feeding method of single-end feeding has the problem of poor anti-interference performance and is difficult to adapt to the use environment of the corresponding products. In addition, the radiation gain of the unbalanced antenna fed by single-end feeding in the directional radiation direction depends on the coupling between the corresponding radiation source and the reference ground, and has high requirements for the area of ​​the reference ground. In other words, the area of ​​the reference ground of the unbalanced antenna fed by single-end feeding is difficult to reduce, and the consistency of the spatial medium between the radiation source and the reference ground is required to be high to avoid affecting the coupling between the radiation source and the reference ground. Therefore, the volume of the existing microwave detector is usually large, and the installation position of the corresponding product will also be greatly restricted. For example, when the corresponding product is a lamp, it is usually necessary to install the microwave detector as a whole on the light-emitting surface of the lamp. Even when the microwave detector adopts a cylindrical antenna, the installation of the microwave detector in the lamp also needs to satisfy the requirement of being located as a whole on the light-emitting surface of the lamp. That is, it is impossible to hide the reference ground behind the light-emitting surface when the corresponding cylindrical radiation source extends out of the light-emitting surface of the lamp. Doing so will easily produce a dark area on the light-emitting surface of the lamp, and therefore it cannot be installed inside a small lamp (such as a downlight or a strip light).

[0004] The directional radiation performance of the antenna fed by differential feeding is less dependent on the area of ​​the reference ground, and has better anti-interference performance than the unbalanced antenna fed by single-ended feeding. Accordingly, when the microwave detector adopts an antenna fed by differential feeding, it can well solve the above-mentioned problems faced when adopting an unbalanced antenna fed by single-ended feeding. However, when an oscillator circuit unit in the form of discrete components or integrated circuits directly outputs a differential signal to feed the antenna, on the one hand, the structure of the oscillator circuit unit will be complicated, resulting in an increase in the volume and / or cost of the oscillator circuit unit. On the other hand, the need for differential mixing will be generated, which will complicate the corresponding mixing detection unit and make it difficult to ensure the isolation between the excitation signal and the echo signal. Therefore, when the microwave detector adopts an antenna fed by differential feeding, for the purpose of simplifying the circuit and reducing costs, the current technical solutions all correspond to Figure 1The oscillation circuit unit 11P that outputs the excitation signal in the form of a single-ended signal is kept in use, and then the excitation signal in the form of a single-ended signal is converted into a differential signal through a standard balun 12P with a single-ended to differential output characteristic to feed the corresponding radiation source 102P. Wherein, in a state where the reference ground 101P is provided at the same time as the antenna 10P based on the requirement of directional radiation, the standard balun 12P or its carrier serving as the feed line of the antenna 10P needs to serve as the physical support structure of the radiation source 102P of the antenna 10P at the same time, so as to form a structural form with a certain interval between the radiation source 102P and the reference ground 101P to generate directional radiation, corresponding to the state where the standard balun 12P is provided between the reference ground 101P and the radiation source 102P of the antenna 10P, in order to reduce the loss of the standard balun 12P as the feed line of the antenna 10P and to ensure the structural characteristics of the single-ended to differential output of the standard balun 12P, the structural form and installation orientation of the standard balun 12P should avoid forming bends in the balanced transmission path to avoid forming additional distributed capacitance, and satisfy the requirement of having as small a coupling to the ground (reference ground 101P) as possible. Therefore, in the actual application of the standard balun 12P, including the corresponding Figure 1 In the technical solution, the structural design and installation orientation of the standard balun 12P are sufficient to avoid forming a bent balanced transmission path, and the length direction of the balanced transmission path of the standard balun 12P is perpendicular to the reference ground 101P.

[0005] There are various types and structures of standard balun 12P that can realize single-ended to differential output, but in principle, they all have a length requirement of λ / 4 or λ / 2 for the corresponding balanced transmission path, where the wavelength parameter λ refers to the wavelength corresponding to the frequency of the excitation signal. Figure 1 In the technical solution of the microwave detector shown in the figure, in order to simplify the structure of the standard balun 12P and meet the spacing requirement of the radiation source 102P of the antenna 10P and the reference ground 101P to form directional radiation, the standard balun 12P adopts Figure 2A The equivalent circuit principle shown, or based on Figure 2A The cascaded equivalent circuit shown is Figure 3A The equivalent circuit principle shown in the figure corresponds to Figure 2A Different example structures of the standard balun 12P are shown in the equivalent circuit principle. FIG. 2B to FIG. 2D is indicated in Figure 3A Different example structures of the standard balun 12P are shown in the equivalent circuit principle. Figure 3B and Figure 3C Corresponding Figures 2A to 3CFrom the equivalent circuit principle and corresponding exemplary structure of the standard balun 12P shown in the figure, it can be seen that the overall length of the standard balun 12 corresponds to the length of its balanced transmission path and remains close to λ / 4. Figure 1 In the technical solution of the microwave detector shown in the figure, the radiation source 102P has two feeding points 1010P, and the radiation source 102P is connected to the standard balun 12P at the two feeding points 1010P to receive the excitation signal in the form of a differential signal, wherein the distance between each feeding point 1010P and the reference ground 101P is kept close to λ / 4, and the height of the corresponding antenna 10P in the direction perpendicular to the reference ground 101P is difficult to be reduced to less than λ / 4. Therefore, the existing use of Figure 1 Although the microwave detector of the technical solution shown can use a relatively small reference ground 101P and realize the hidden installation of the microwave detector in the corresponding product, for example, when the corresponding product is a lamp, the reference ground 101P is hidden behind the light-emitting surface by extending the radiation source 102P from the light-emitting surface of the lamp. However, the size of the microwave detector in the direction perpendicular to the reference ground 101P is limited by the standard balun 12P and is difficult to reduce. For example, when the frequency of the excitation signal is in the 5.8GHz ISM band, the height of the antenna 10P in the direction perpendicular to the reference ground 101P is about 13mm. Correspondingly, when the microwave detector is adapted to the corresponding product, there are still certain requirements for the size of the product, and when the product is a lamp, a dark area may still be generated on the light-emitting surface of the lamp due to the high height of the antenna 10P. Summary of the invention

[0006] One object of the present invention is to provide a non-standard balun for single-ended to differential output and a dual-dipole differential antenna, wherein the non-standard balun for single-ended to differential output is a three-port component composed of a first conductor and a second conductor that are coupled to each other, and the non-standard balun has an unbalanced port and two balanced ports in a grounded state, wherein the physical length corresponding to the one-wavelength electrical length of the first conductor and the second conductor is defined as L, the two balanced ports are located at the same end of the non-standard balun, and the distance between the two ends of the corresponding conductors with the balanced ports is less than or equal to 3L / 16, wherein when an unbalanced single-ended signal is connected to the unbalanced port of the non-standard balun, the signals output by the two balanced ports are inverted within an error range of ±30° and a balanced differential signal is output, that is, the phase difference of the signals output by the two balanced ports is greater than or equal to 150° and less than or equal to 210°, and the standard balun has a single-ended to differential output characteristic.

[0007] Another object of the present invention is to provide a non-standard balun and a dual-dielectric differential antenna with single-ended to differential output, wherein the distance between the two ends of the corresponding conductor with the balanced port of the non-standard balun is less than or equal to 3L / 16, and the corresponding non-standard balun has an overall length that is significantly reduced relative to the standard balun, and has a single-ended to differential output characteristic with the standard balun, so that the non-standard balun can be used as a feeding line of the dual-dielectric differential antenna to realize differential feeding of the dual-dielectric differential antenna, and when used as a feeding line of the dual-dielectric differential antenna, the distance between the feeding point of the dual-dielectric differential antenna and the reference ground can be reduced to less than or equal to 3L / 16, thereby facilitating the miniaturization of the dual-dielectric differential antenna and improving the applicability of the dual-dielectric differential antenna.

[0008] Another object of the present invention is to provide a non-standard balun and a dual-element differential antenna for single-ended to differential output, wherein the shortening and / or bending design of the balanced transmission path of the standard balun can form the non-standard balun, that is, the structural form of the non-standard balun deviates from the inertial cognition that the balanced transmission path of the standard balun has a length of L / 4 and / or the inertial cognition that the balanced transmission path should avoid forming bends in the balanced transmission path in terms of structural form, and the corresponding non-standard balun has an overall length that is significantly reduced relative to the standard balun, which is specifically embodied in that the distance between the two ends of the corresponding conductor of the non-standard balun with the balanced port is less than or equal to 3L / 16.

[0009] Another object of the present invention is to provide a non-standard balun and a dual-dielectric differential antenna for single-ended to differential output, wherein when the non-standard balun has a shortened and / or bent balanced transmission path relative to the standard balun so that the distance between the two ends of the corresponding conductor with the balanced port is less than or equal to 3L / 16, the non-standard balun also has an increased loss relative to the standard balun, wherein the loss of the non-standard balun can be reduced based on the enhancement of the coupling strength between the first conductor and the second conductor, and correspondingly, when the non-standard balun is used as the feeding line of the dual-dielectric differential antenna, the dual-dielectric differential antenna can form an obvious resonant frequency point in the ISM frequency band at the frequency corresponding to the aforementioned wavelength, and thus the non-standard balun is suitable for being used as the feeding line of the dual-dielectric differential antenna to realize differential feeding of the dual-dielectric differential antenna.

[0010] Another object of the present invention is to provide a non-standard balun and a dual-element differential antenna for single-ended to differential output, wherein the coupling strength between the first conductor and the second conductor of the non-standard balun can be enhanced based on the structural design of the first conductor and the second conductor when the coupling distance between the first conductor and the second conductor is shortened and / or the coupling area is increased relative to the standard balun, thereby reducing the loss of the non-standard balun.

[0011] Another object of the present invention is to provide a non-standard balun and a dual-dipole differential antenna with single-ended to differential output, wherein the coupling strength between the first conductor and the second conductor of the non-standard balun can be enhanced by introducing a physical medium in the coupling space between the first conductor and the second conductor, thereby reducing the loss of the non-standard balun.

[0012] Another object of the present invention is to provide a non-standard balun and a dual-dipole differential antenna with single-ended to differential output, wherein a solid medium is introduced into the coupling space between the first conductor and the second conductor of the non-standard balun and has a higher dielectric constant than the air medium, and the physical length L corresponding to the electrical length of one wavelength of the first conductor and the second conductor can be reduced, so that when the non-standard balun has a shortened and / or bent balanced transmission path relative to the standard balun so that the distance between the two ends of the corresponding conductor with the balanced port is less than or equal to 3L / 16, the actual physical size of the non-standard balun is further reduced.

[0013] Another object of the present invention is to provide a non-standard balun and a dual-element differential antenna for single-ended to differential output, wherein the first conductor and the second conductor of the non-standard balun are arranged in the form of a strip conductor carried on a corresponding circuit board, and a physical medium is introduced into the coupling space between the first conductor and the second conductor of the non-standard balun.

[0014] Another object of the present invention is to provide a non-standard balun and a dual-diode differential antenna with single-ended to differential output, wherein a physical medium is introduced into the coupling space between the first conductor and the second conductor of the non-standard balun, and the structural state of mutual coupling between the first conductor and the second conductor can be maintained during the production and use of the dual-diode differential antenna, especially when the coupling distance between the first conductor and the second conductor is further reduced for the purpose of increasing the coupling strength between the first conductor and the second conductor, thereby facilitating the consistency and stability of the dual-diode differential antenna.

[0015] According to one aspect of the present invention, the present invention provides a non-standard balun for converting single-ended to differential output, the non-standard balun comprising:

[0016] A first conductor and a second conductor coupled to the first conductor, wherein in a state where one end of the first conductor is grounded, the non-standard balun has an unbalanced port and two balanced ports, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are located at the other end of the non-standard balun, wherein the physical length corresponding to one wavelength electrical length of the first conductor and the second conductor is defined as L, and the distance between the two ends of the corresponding conductors having the balanced ports is less than or equal to 3L / 16, wherein when a single-ended signal in an unbalanced state is connected to the unbalanced port of the non-standard balun, the phase difference of the signals output by the two balanced ports is greater than or equal to 150° and less than or equal to 210°, and has a single-ended to differential output characteristic.

[0017] In one embodiment, the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are respectively formed at the other end of the first conductor and the other end of the second conductor.

[0018] In one embodiment, the first conductor and the second conductor are bent in a discontinuously coupled manner when they are configured as columnar conductors.

[0019] In one embodiment, the first conductor and the second conductor are provided as two columnar conductors close to each other in a state of being parallel to each other.

[0020] In one embodiment, a physical medium is introduced into the coupling space between the first conductor and the second conductor.

[0021] In one embodiment, the coupling space between the first conductor and the second conductor is introduced into a solid medium by spraying an insulating layer on the surface of the first conductor and / or the second conductor based on a spraying process.

[0022] In one embodiment, the coupling space between the first conductor and the second conductor is introduced with a solid medium which is an insulating oxide formed on the surface of the first conductor and / or the second conductor by oxidation.

[0023] In one embodiment, the physical medium introduced into the coupling space between the first conductor and the second conductor is an insulating glue bonded between the first conductor and the second conductor.

[0024] In one embodiment, the coupling space between the first conductor and the second conductor is introduced into a solid medium which is an insulating layer spaced between the first conductor and the second conductor.

[0025] In one embodiment, the first conductor and the second conductor are provided in the form of a ribbon conductor carried on a corresponding circuit board.

[0026] In one embodiment, the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the other end of the first conductor has a forked structure and has two forked ends, wherein the two balanced ports are respectively formed at the two forked ends of the first conductor.

[0027] According to another aspect of the present invention, the present invention also provides a dual-element differential antenna, the dual-element differential antenna comprising:

[0028] - reference ground;

[0029] A non-standard balun, wherein the non-standard balun comprises a first conductor and a second conductor coupled to the first conductor, wherein in a state where one end of the first conductor is electrically connected to the reference ground and is grounded, the non-standard balun has an unbalanced port and two balanced ports, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are located at the other end of the non-standard balun, wherein the physical length corresponding to one wavelength electrical length of the first conductor and the second conductor is defined as L, and the distance between the two ends of the corresponding conductor having the balanced port is less than or equal to 3L / 16; and

[0030] A pair of oscillators, wherein the two oscillators are respectively fed and connected to the two balanced ports of the non-standard balun and are arranged as conductors extending with the corresponding balanced ports as ends, wherein there is a point on each oscillator where the distance between the oscillator and the corresponding balanced port is greater than or equal to L / 16.

[0031] In one embodiment, the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are respectively formed at the other end of the first conductor and the other end of the second conductor.

[0032] In one embodiment, the first conductor and the second conductor are provided as two columnar conductors close to each other in a state of being parallel to each other.

[0033] In one embodiment, the dual-element differential antenna also includes a circuit substrate, and a grounding pin extending from the grounded end of the first conductor, and an unbalanced access pin extending from the unbalanced port of the second conductor, wherein the reference ground is carried on the circuit substrate in the form of a copper-clad layer, wherein the first conductor and the second conductor are respectively fixed to the circuit substrate via the grounding pin and the unbalanced access pin, wherein when the first conductor is fixed to the circuit substrate via the grounding pin, the grounded end of the first conductor is electrically connected to the reference ground via the grounding pin and is grounded.

[0034] In one embodiment, the ground pin and the unbalanced access pin extend from a grounded end of the first conductor and an unbalanced port of the second conductor in a direction away from each other and in a direction close to the reference ground, respectively.

[0035] In one embodiment, the first conductor and the second conductor are bent in a discontinuously coupled manner when they are configured as columnar conductors.

[0036] In one embodiment, a physical medium is introduced into the coupling space between the first conductor and the second conductor.

[0037] In one embodiment, the first conductor and the second conductor are provided in the form of a ribbon conductor carried on a corresponding circuit board.

[0038] In one embodiment, the two oscillators have opposite initial extension directions with the corresponding balanced ports as ends, and the distance between the balanced ports and the reference ground is greater than or equal to the distance between the other end of the oscillator extending with the balanced port as an end and the reference ground.

[0039] In one embodiment, the two oscillators extend in opposite directions parallel to the reference ground with the corresponding balanced ports as ends.

[0040] In one embodiment, the two oscillators sequentially extend in opposite directions parallel to the reference ground and in a direction toward the reference ground with the corresponding balanced ports as ends.

[0041] In one embodiment, the two oscillators sequentially extend in opposite directions parallel to the reference ground, extend in a direction toward the reference ground, and extend toward each other in a direction parallel to the reference ground with the corresponding balanced ports as ends.

[0042] In one embodiment, the two oscillators are arranged unbalanced, and the coupling strength between the oscillator fed and connected to the second conductor and the reference ground is greater than the coupling strength between the other oscillator and the reference ground, or the impedance of the oscillator fed and connected to the second conductor is greater than the impedance of the other oscillator.

[0043] Further objects and advantages of the present invention will be fully apparent from an understanding of the following description and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 The present invention is a schematic diagram of the structural principle of an existing microwave detector when an antenna fed by differential feeding is used.

[0045] Figure 2A The basic equivalent circuit schematic diagram of an existing standard balun used as the feed line of the antenna of a microwave detector.

[0046] Figure 2B A structural diagram of the standard balun corresponding to the above-mentioned basic equivalent circuit principle.

[0047] Figure 2C Another structural schematic diagram of the standard balun corresponding to the above-mentioned basic equivalent circuit principle.

[0048] Figure 2D Another structural schematic diagram of the standard balun corresponding to the above-mentioned basic equivalent circuit principle.

[0049] Figure 3A Another equivalent circuit schematic diagram of the standard balun formed by cascading the above basic equivalent circuit principles.

[0050] Figure 3B A structural schematic diagram of the standard balun corresponding to the above-mentioned equivalent circuit schematic diagram.

[0051] Figure 3C Another structural schematic diagram of the standard balun corresponding to the above equivalent circuit schematic diagram.

[0052] Figure 4 It is a schematic diagram of the structure of a dual-dipole differential antenna of the present invention when the standard balun is used as a feeding circuit, and the radiation pattern and S11 curve corresponding to the structure.

[0053] Figure 5A It is a structural schematic diagram of the dual-dipole differential antenna of the present invention when the balanced transmission path of the standard balun is shortened, and the radiation pattern and S11 curve corresponding to the structure.

[0054] Figure 5BIt is a schematic diagram of the phase distribution of the original balanced port of the standard balun when the balanced transmission path is shortened.

[0055] Figure 6 Schematic diagram of the structure of a dual-dipole differential antenna according to an embodiment of the present invention and the radiation pattern and S11 curve corresponding to the structure.

[0056] Figure 7 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0057] Figure 8 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0058] Fig. 9 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0059] Fig.10 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0060] Fig.11 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0061] Fig.12 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0062] Fig.13 FIG. 4 is a schematic structural diagram of a dual-element differential antenna according to another embodiment of the present invention.

[0063] Fig.14A FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0064] Fig. 14B FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0065] Fig.15 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0066] Fig.16FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0067] Fig.17 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure.

[0068] Fig.18 FIG. 1 is a schematic diagram of the structure of a dual-dipole differential antenna according to another embodiment of the present invention and a radiation pattern and an S11 curve corresponding to the structure. DETAILED DESCRIPTION

[0069] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0070] Those skilled in the art should understand that, in the disclosure of the present invention, the orientation or position relationship indicated by the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0071] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the elements may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0072] The present invention provides a non-standard balun for single-ended to differential output and a dual-dipole differential antenna, wherein the non-standard balun has an overall length that is significantly reduced compared to a standard balun, and has a single-ended to differential output characteristic like the standard balun, so that the non-standard balun can be used as a feeding line of the dual-dipole differential antenna to realize differential feeding of the dual-dipole differential antenna, and when used as a feeding line of the dual-dipole differential antenna, the height of the dual-dipole differential antenna can be reduced, thereby facilitating the miniaturization of the dual-dipole differential antenna and improving the applicability of the dual-dipole differential antenna.

[0073] Specifically, referring to the accompanying drawings of the present invention, Figures 2A to 3CAs shown, when the standard balun 12P is used as a feeding line for differential feeding of the corresponding antenna, the standard balun 12P adopts Figure 2A The equivalent circuit principle shown, or based on Figure 2A The equivalent circuit shown is cascaded using Figure 3A The equivalent circuit principle shown in the figure corresponds to Figure 2A Different example structures of the standard balun 12P are shown in the equivalent circuit principle. FIG. 2B to FIG. 2D is indicated in Figure 3A Different example structures of the standard balun 12P are shown in the equivalent circuit principle. Figure 3B and Figure 3C The standard balun 12P is a three-port device composed of a first conductor 121P and a second conductor 122P coupled to each other, and the standard balun 12P has an unbalanced port 1201P and two balanced ports 1202P when one end of the first conductor 121P is grounded, wherein the unbalanced port 1201P is formed at one end of the second conductor 122P and is located at the same end of the standard balun 12P as the grounded end of the first conductor 121P, and the two balanced ports 1202P are located at the other end of the standard balun 12P. For example, the two balanced ports 1202P correspond to FIG. 2B to FIG. 2D are formed at the other end of the first conductor 121P and the other end of the second conductor 122P, or corresponding to Figure 3B and 3C The other end of the first conductor 121P has a forked structure, which is formed at the two forked ends of the first conductor 122P, respectively, wherein the physical length corresponding to the one-wavelength electrical length of the first conductor 121P and the second conductor 122P is defined as L, and based on the basic theory that the balanced transmission path of the standard balun 12P has an L / 4 length, the transmission path between the two ends of the corresponding conductor (121P and / or 122P) with the balanced port 1202P is the balanced transmission path and satisfies the L / 4 length, and based on the basic theory that the standard balun 12P should avoid forming bends in the balanced transmission path in terms of structural morphology to avoid forming additional distributed capacitance, and satisfying the minimum possible coupling to the ground when used as a feeding line, the distance between the two ends of the corresponding conductor (121P and / or 122P) with the balanced port 1202P is consistent with the transmission path between the two ends and satisfies the L / 4 length.

[0074] Further, referring to the accompanying drawings of the present invention, Figure 4As shown, in order to fully demonstrate the aforementioned advantages of the non-standard balun of the present invention over the standard balun, the structure of the dual-element differential antenna using the standard balun and the corresponding radiation pattern and S11 curve of the structure are respectively illustrated. The dual-element differential antenna 10 has a reference ground 11, a standard balun 12P and a pair of oscillators 13, wherein the standard balun 12P is set between the reference ground 11 and the pair of oscillators 13 as a feeding line of the pair of oscillators 13 and is connected to the feeding of the pair of oscillators 13. Specifically in this example structure, the structure of the standard balun 12P corresponds to Figure 2A According to the principle of the equivalent circuit shown in the figure, based on the basic theory that the balanced transmission path of the standard balun 12P has a length of L / 4, the transmission paths between the two ends of the corresponding conductors (the first conductor 121P and the second conductor 122P) with the balanced port 1202P satisfy the L / 4 length, based on the basic theory that the standard balun 12P should avoid forming bends in the balanced transmission path in terms of structural morphology to avoid forming additional distributed capacitance, and satisfy the minimum possible coupling to the ground (reference ground 11) when used as a feeding line, the distance between the two ends of the corresponding conductors (the first conductor 121P and the second conductor 122P) with the balanced port 1202P is consistent with the transmission path between the two ends and satisfies the L / 4 length, and the first conductor 121P and the second conductor 122P are perpendicular to the reference ground 11. Therefore, in this example structure, the height of the dual-element differential antenna 10 in the direction perpendicular to the reference ground 11 is L / 4. Specifically, when the operating frequency of the dual-element differential antenna 10 is set to the 5.8 GHz ISM band, the height of the dual-element differential antenna 10 in the direction perpendicular to the reference ground 11 is approximately 13 mm.

[0075] The non-standard balun of the present invention is formed based on the structure of the above-mentioned standard balun 12P by shortening and / or bending the balanced transmission path of the standard balun 12P, that is, the structural form of the non-standard balun deviates from the inertial cognition that the balanced transmission path of the standard balun 12P has a length of L / 4 and / or the inertial cognition that the balanced transmission path should avoid forming bends in the balanced transmission path in terms of structural form. The corresponding non-standard balun has an overall length that is significantly reduced relative to the standard balun 12P, which is specifically reflected in that the distance between the two ends of the corresponding conductor of the shortened and / or bent standard balun 12P with the balanced port 1202P is less than or equal to 3L / 16.

[0076] That is to say, reference Figure 5AThe non-standard balun 12 formed by shortening and / or bending the balanced transmission path of the standard balun 12P on the basis of the structure of the aforementioned standard balun 12P is a three-port device consisting of a first conductor 121 and a second conductor 122 coupled to each other, and the non-standard balun 12 has an unbalanced port 1201 and two balanced ports 1202 corresponding to the state in which one end of the first conductor 121 is electrically connected to the reference ground 11 and is grounded, wherein the unbalanced port 1201 is formed at one end of the second conductor 122 and is located at the same end of the non-standard balun 12 as the grounded end of the first conductor 121, and the two balanced ports 1202 are located at the other end of the non-standard balun 12, for example, the two balanced ports 1202 are respectively formed at the other end of the first conductor 121 and the second conductor 122. The other end of the second conductor 122, or the other end of the first conductor 121 has a forked structure, which is respectively formed at the two forked ends of the first conductor 122, wherein the physical length corresponding to the one-wavelength electrical length of the first conductor 121 and the second conductor 122 is defined as L, and the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 is less than or equal to 3L / 16, wherein when an unbalanced single-ended signal is connected to the unbalanced port 1201 of the non-standard balun 12, the signals output by the two balanced ports 1202 are inverted within an error range of ±30° and output a differential signal in a balanced state, that is, the phase difference of the signals output by the two balanced ports 1202 is greater than or equal to 150° and less than or equal to 210°, and has a single-ended to differential output characteristic with the standard balun 12P.

[0077] Specifically, referring to the accompanying drawings of the present invention, Figure 5A and Figure 5B As shown, in Figure 4 Based on the structure of the dual-element differential antenna 10 using the standard balun 12P, the balanced transmission path of the standard balun 12P is shortened to obtain Figure 5A The dual-element differential antenna 10 shown in the figure, specifically in this structural example, the balanced transmission path of the standard balun 12P is shortened to 3 / 4 of the original length (i.e., 3L / 16), and the output phase of the two balanced ports 1202 of the non-standard balun 12 formed corresponds to Figure 5B It tends to 193.7° and has the single-ended to differential output characteristics of the standard balun 12P.

[0078] It is worth mentioning that the distance between the two ends of the corresponding conductor (121 and / or 122) of the non-standard balun 12 with the balanced port 1202 is less than or equal to 3L / 16, and the corresponding non-standard balun 12 has an overall length that is significantly reduced relative to the standard balun 12P, and has a single-ended to differential output characteristic like the standard balun 12P. Therefore, the non-standard balun 12 can be used as a feeding line of the double-dielectric differential antenna 10 to realize differential feeding of the double-dielectric differential antenna 10, and when used as a feeding line of the double-dielectric differential antenna 10, it can reduce the height of the double-dielectric differential antenna 10 in a direction perpendicular to the reference ground 11, which is beneficial to the miniaturization of the double-dielectric differential antenna 10 and improves the applicability of the double-dielectric differential antenna 10.

[0079] Corresponds to Figure 5A It can be seen from the S11 curve in that when the non-standard balun 12 has a shortened and / or bent balanced transmission path relative to the standard balun 12P so that the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 is less than or equal to 3L / 16, the non-standard balun 12 also has an increased loss relative to the standard balun 12P. However, it can be seen from the following structural example of the present invention that the loss of the non-standard balun 12 can be reduced based on the enhancement of the coupling strength between the first conductor 121 and the second conductor 122, and when the non-standard balun 12 is used as the feeding line of the double-dip differential antenna 10, the double-dip differential antenna 10 can form an obvious resonant frequency point in the ISM frequency band at the frequency corresponding to the wavelength in the aforementioned wavelength electrical length, so the non-standard balun 12 is still suitable as the feeding line of the double-dip differential antenna 10 to realize differential feeding of the double-dip differential antenna 10.

[0080] Specifically, the coupling strength between the first conductor 121 and the second conductor 122 of the non-standard balun 12 can be enhanced based on the structural design of the first conductor 121 and the second conductor 122 when the coupling distance between the first conductor 121 and the second conductor 122 is shortened and / or the coupling area is increased relative to the standard balun 12P, thereby reducing the loss of the non-standard balun.

[0081] Corresponding to the accompanying drawings of the present invention Figure 6 As shown, in Figure 5A Based on the structure of the dual-element differential antenna 10 shown in the figure, based on the structural design of the first conductor 121 and the second conductor 122, the coupling distance between the first conductor 121 and the second conductor 122 is relative to Figure 5AThe structure shown is reduced, and accordingly the dual-element differential antenna 10 forms an obvious resonance frequency point in the ISM band at a frequency corresponding to the wavelength in the aforementioned wavelength electrical length.

[0082] Specifically in Figure 6 In the illustrated structural example, the corresponding ISM frequency band is the 5.8 GHz ISM frequency band, and the coupling distance between the first conductor 121 and the second conductor 122 is reduced to about 0.32 mm.

[0083] Corresponding to the accompanying drawings of the present invention Figure 7 As shown, in Figure 5A Based on the structure of the dual-element differential antenna 10 shown in the figure, based on the structural design of the first conductor 121 and the second conductor 122, the coupling area between the first conductor 121 and the second conductor 122 is relatively Figure 5A The illustrated structure is increased, and accordingly the dual-element differential antenna 10 forms an obvious resonance frequency point in the ISM band at a frequency corresponding to the wavelength in the aforementioned wavelength electrical length.

[0084] Specifically in Figure 7 In the illustrated structural example, the corresponding ISM frequency band is the 5.8 GHz ISM frequency band, and the coupling area between the first conductor 121 and the second conductor 122 is increased based on the increase in the line width of the first conductor 121 and the second conductor 122 configured as columnar conductive lines.

[0085] In addition, the coupling strength between the first conductor 121 and the second conductor 122 of the non-standard balun 12 can be further enhanced by introducing a physical medium into the coupling space between the first conductor 121 and the second conductor 122, thereby reducing the loss of the non-standard balun.

[0086] Corresponding to the accompanying drawings of the present invention Figure 8 As shown, in Figure 5A On the basis of the structure of the dual-element differential antenna 10 shown in the figure, by introducing a physical medium into the coupling space between the first conductor 121 and the second conductor 122, a physical medium is introduced into the coupling space between the first conductor 121 and the second conductor 122, and the physical medium has a higher dielectric constant than the air medium, thereby enhancing the coupling strength between the first conductor 121 and the second conductor 122. Accordingly, the dual-element differential antenna 10 forms an obvious resonant frequency point in the ISM frequency band at the frequency corresponding to the wavelength in the aforementioned wavelength electrical length.

[0087] Specifically in Figure 8In the illustrated structural example, the corresponding ISM frequency band is the 5.8 GHz ISM frequency band, and the physical medium introduced between the first conductor 121 and the second conductor 122 is a physical medium with a dielectric constant of 1.3.

[0088] It is worth mentioning that in a state where a physical medium with a higher dielectric constant than the air medium is introduced into the coupling space between the first conductor 121 and the second conductor 122 of the non-standard balun 12, the physical length L corresponding to the one-wavelength electrical length of the first conductor 121 and the second conductor 122 can be reduced, so that when the non-standard balun 12 has a shortened and / or bent balanced transmission path relative to the standard balun 12P so that the distance between the two ends of the corresponding conductor (121 and / or 122) with the balanced port 1202 is less than or equal to 3L / 16, the actual physical size of the non-standard balun 12 is further reduced.

[0089] In particular, in the above-mentioned structural examples of the present invention, the first conductor 121 and the second conductor 122 are arranged as two columnar conductors close to each other in a parallel state, the corresponding unbalanced port 1201 is formed at one end of the second conductor 122 and is located at the same end of the non-standard balun 12 as the grounded end of the first conductor 121, and the two balanced ports 1202 are respectively formed at the other end of the first conductor 121 and the other end of the second conductor 122 in a state of being located at the other end of the non-standard balun 12, and the distance between the two ends of the first conductor 121 and the second conductor 122 having the balanced port 1202 is less than or equal to 3L / 16.

[0090] Furthermore, in the above-mentioned structural examples of the present invention, the dual-element differential antenna 10 further includes a circuit substrate 14, and a grounding pin 15 extending from the grounded end of the first conductor 121, and an unbalanced access pin 16 extending from the unbalanced port 1201 of the second conductor 122, wherein the reference ground 11 is carried on the circuit substrate 14 in the form of a copper-clad layer, and the grounding pin 15 and the unbalanced access pin 16 are respectively extended from the grounded end of the first conductor 121 and the unbalanced port 1201 of the second conductor 122 in a direction away from each other, and The first conductor 121 and the second conductor 122 extend in a direction close to the reference ground 21, wherein the first conductor 121 and the second conductor 122 are fixed to the circuit substrate 14 via the ground pin 15 and the unbalanced access pin 16, respectively, so that when the ground pin 15 and the unbalanced access pin 16 fixed to the circuit substrate 14 are fixed and electrically connected accordingly by welding, electrical contact between the first conductor 121 and the second conductor 122 close to each other can be avoided, and the stability of the support of the first conductor 121 and the second conductor 122 to a pair of the vibrators 13 can be enhanced.

[0091] In particular, in the above-mentioned structural examples of the present invention, when the first conductor 121 and the second conductor 122 are fixed to the circuit substrate 14 via the grounding pin 15 and the unbalanced access pin 16 respectively, the grounded end of the first conductor 121 is electrically connected to the reference ground 11 via the grounding pin 15 and is grounded.

[0092] It is worth mentioning that the non-standard balun 12 is formed by shortening and / or bending the balanced transmission path of the standard balun 12P on the basis of the structure of the aforementioned standard balun 12P. Specifically, in the above-mentioned structural examples of the present invention, the non-standard balun 12 is formed by shortening and / or bending the balanced transmission path of the standard balun 12P. Figure 2C The structure of the standard balun 12P shown in the figure is based on the shortening of the balanced transmission path of the standard balun 12P, wherein the non-standard balun 12 is formed based on the shortening and / or bending of the balanced transmission path of the standard balun 12P on the basis of the structure of the aforementioned standard balun 12P, and the non-standard balun 12 has a variety of structural forms with the standard balun 12P. For example, the non-standard balun 12 can be in Figure 2B and Figure 2D The structure of the standard balun 12P shown in the figure is based on shortening and / or bending the balanced transmission path of the standard balun 12P, which can be Figure 3B and Figure 3C The structure of the standard balun 12P shown in the figure is based on shortening and / or bending the balanced transmission path of the standard balun 12P, and can also be formed in Figure 2CThe structure of the standard balun 12P shown in the figure is based on the bending of the balanced transmission path of the standard balun 12P, and can also be Figure 2C The structure of the standard balun 12P shown is based on shortening and bending the balanced transmission path of the standard balun 12P, and the present invention is not limited thereto.

[0093] As mentioned above, the coupling strength between the first conductor 121 and the second conductor 122 of the non-standard balun 12 can be enhanced based on the structural design of the first conductor 121 and the second conductor 122 when the coupling distance between the first conductor 121 and the second conductor 122 is shortened and / or the coupling area is increased relative to the standard balun 12P, and can also be enhanced by introducing a physical medium into the coupling space between the first conductor 121 and the second conductor 122, wherein different enhancement methods for the coupling strength between the first conductor 121 and the second conductor 122 can be combined with each other to further reduce the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 within a range of less than or equal to 3L / 16 while enhancing the coupling strength between the first conductor 121 and the second conductor 122, thereby reducing the height of the dual-element differential antenna 10 in the direction perpendicular to the reference ground.

[0094] For example, referring to the accompanying drawings of the present invention, Fig. 9 As shown, in Fig. 9 In this example structure, the coupling strength between the first conductor 121 and the second conductor 122 is enhanced and combined with a method of shortening the coupling distance between the first conductor 121 and the second conductor 122 and a method of introducing a solid medium into the coupling space between the first conductor 121 and the second conductor 122. Then, the distance between the first conductor 121 having the balanced port 1202 and the second conductor 122 can be further reduced within a range of less than or equal to 3L / 16, corresponding to the height of the dual-element differential antenna 10 relative to the reference ground direction. Figures 6 to 8 The illustrated structure is further reduced.

[0095] It is worth mentioning that when the coupling strength between the first conductor 121 and the second conductor 122 is strengthened based on the shortening of the coupling distance between the first conductor 121 and the second conductor 122, the first conductor 121 and the second conductor 122 may contact each other due to the too close coupling distance, thereby destroying the structural characteristics of the mutual coupling between the first conductor 121 and the second conductor 122. Therefore, when the coupling strength between the first conductor 121 and the second conductor 122 is strengthened based on the shortening of the coupling distance between the first conductor 121 and the second conductor 122, the coupling strength between the first conductor 121 and the second conductor 122 is preferably further strengthened by introducing a solid medium into the coupling space between the first conductor 121 and the second conductor 122, so as to avoid the electrical contact between the first conductor 121 and the second conductor 122 which are close to each other and ensure the structural stability of the dual-element differential antenna 10.

[0096] Further reference is made to the accompanying drawings of the present invention. Fig.10 As shown, in Fig.10 In this example structure, the coupling strength between the first conductor 121 and the second conductor 122 is enhanced by combining the manner of increasing the coupling area between the first conductor 121 and the second conductor 122 and the manner of introducing a solid medium into the coupling space between the first conductor 121 and the second conductor 122. Then, the distance between the first conductor 121 having the balanced port 1202 and the ends of the second conductor 122 can be further reduced within a range of less than or equal to 3L / 16, corresponding to the height of the dual-element differential antenna 10 perpendicular to the reference ground direction relative to Figures 6 to 8 The illustrated structure is further reduced.

[0097] Further reference is made to the accompanying drawings of the present invention. Fig.11 As shown, in Fig.11 In this example structure, the coupling strength between the first conductor 121 and the second conductor 122 is enhanced by combining the manner of shortening the coupling distance between the first conductor 121 and the second conductor 122 and the manner of increasing the coupling area between the first conductor 121 and the second conductor 122. Then, the distance between the first conductor 121 having the balanced port 1202 and the second conductor 122 can be further reduced within a range of less than or equal to 3L / 16, corresponding to the height of the dual-element differential antenna 10 relative to the reference ground direction. Figures 6 to 8 The illustrated structure is further reduced.

[0098] As mentioned above, the distance between the two ends of the first conductor 121 and the second conductor 122 having the balanced port 1202 can be shortened to less than or equal to 3L / 16 based on shortening the balanced transmission path of the standard balun 12P, can be shortened to less than or equal to 3L / 16 based on bending the balanced transmission path of the standard balun 12P, and can be shortened to less than or equal to 3L / 16 based on shortening and bending the balanced transmission path of the standard balun 12P. Accordingly, the non-standard balun 12 can still have the single-ended to differential output characteristics with the standard balun 12P, wherein the loss of the non-standard balun 12 increased due to shortening and / or bending of the balanced transmission path of the standard balun 12P can be reduced based on strengthening the coupling strength between the first conductor 121 and the second conductor 122, so that the non-standard balun 12 is still suitable as the feeding line of the dual-element differential antenna 10 to realize differential feeding of the dual-element differential antenna 10. Therefore, the corresponding first conductor 121 and the second conductor 122 have various structural forms, but in the state where the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 of the non-standard balun 12 is less than or equal to 3L / 16, the non-standard balun 12 has structural features that are obviously different from the standard balun 12P and deviate from the inertial cognition of the standard balun 12P, and those skilled in the art can, based on the teachings of the ideas of the present invention, obtain a suitable structure of the non-standard balun 12 for the purpose of strengthening the coupling strength between the first conductor 121 and the second conductor 122, so that the non-standard balun 12 is suitable as the feeding line of the dual-element differential antenna 10 to realize differential feeding of the dual-element differential antenna 10.

[0099] That is, the structure of the non-standard balun 12 is diverse. When the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 of the non-standard balun 12 is less than or equal to 3L / 16, the specific structure of the non-standard balun 12 does not constitute a limitation on the present invention, nor is it limited to the present invention. FIG. 2B to FIG. 2D , Figure 3B as well as Figure 3C The structure of the standard balun 12P shown in the figure is based on a structural form formed by shortening and / or bending the balanced transmission path of the standard balun 12P.

[0100] For example, in some structures of the non-standard balun 12 of the present invention, specifically refer to the accompanying drawings of the specification of the present invention. Fig.12In the non-standard balun structure shown in the figure, the first conductor 121 and the second conductor 122 are bent in an intermittent coupling manner when the balanced transmission path of the non-standard balun 12 is not shortened, so that the distance between the two ends of the first conductor 121 and the second conductor 122 having the balanced port 1202 is less than or equal to 3L / 16. Accordingly, the non-standard balun 12 can still maintain a low loss based on the coupling enhancement method of shortening the coupling distance and the coupling enhancement method of introducing a physical medium in the coupling space, and is suitable as a feeding line for the dual-element differential antenna 10.

[0101] It is worth mentioning that in the manner of enhancing the coupling strength between the first conductor 121 and the second conductor 122, the specific manner of introducing the entity medium into the coupling space between the first conductor 121 and the second conductor 122 and the corresponding structural forms formed are various, for example, corresponding to Fig.13 In the structural example shown, when the first conductor 121 and the second conductor 122 of the non-standard balun 12 are arranged in the form of a strip conductor carried on a corresponding circuit board, a state in which a physical medium is introduced into the coupling space between the first conductor 121 and the second conductor 122 of the non-standard balun 12 can be formed.

[0102] In some embodiments of the present invention, the physical medium introduced into the coupling space between the first conductor 121 and the second conductor 122 is an insulating material spaced between the first conductor 121 and the second conductor 122, such as ceramic spaced between the first conductor 121 and the second conductor 122 in a sheet form, or ceramic arranged in other shapes and spaced between the first conductor 121 and the second conductor 122. Specifically, it can be an insulating layer sprayed on the surface of the first conductor 121 and / or the second conductor 122 based on a spraying process, or an insulating oxide formed on the surface of the first conductor 121 and / or the second conductor 122 by oxidation, or an insulating glue bonded between the first conductor 121 and the second conductor 122, or an insulating layer spaced between the first conductor 121 and the second conductor 122, such as an insulating layer set as a thin PCB or FPC, and the present invention is not limited to this.

[0103] In particular, in the dual-element differential antenna 10 of the present invention, a pair of the dipoles 13 are respectively fed and connected to the two balanced ports 1202 of the non-standard balun 12, corresponding to a state in which one of the dipoles 13 is fed and connected to one of the balanced ports 1202, the dipole 13 is set as a conductor extending with the balanced port 1202 as an end, and a state in which the other dipole 13 is fed and connected to the other balanced port 1202, the other dipole 13 is set as a conductor extending with the other balanced port 1202 as an end, that is, a pair of the dipoles 13 are respectively fed and connected The two balanced ports 1202 of the non-standard balun 12 are arranged as conductors extending with the corresponding balanced port 1202 as the end, wherein there is a point on each of the vibrators 13 at a distance between the vibrator 13 and the corresponding balanced port 1202 greater than or equal to L / 16, corresponding to a state in which the vibrator 13 is arranged as a columnar conductor, the vibrator 13 has a length greater than or equal to L / 16 from the corresponding balanced port 1202, and a state in which the vibrator 13 is arranged as a planar conductor, the vibrator 13 has a straight transmission path greater than or equal to L / 16 from the corresponding balanced port 1202.

[0104] Further, in the above-mentioned structural examples of the present invention, the vibrator 13 is provided in the form of a columnar conductor, and can be alternatively provided in the form of a strip conductor carried on a corresponding circuit board, wherein the two vibrators 13 have opposite initial extension directions with the corresponding balanced port 1202 as the end, and the distance between the balanced port 1202 and the reference ground 11 is greater than or equal to the distance between the other end of the vibrator 13 extending with the balanced port 1202 as the end and the reference ground 11. For example, in the case corresponding to Fig.13 In the structural example, the two vibrators 13 extend in opposite directions parallel to the reference ground 11 with the corresponding balanced ports 1202 as ends; Figures 4 to 10 In the structural example, the two vibrators 13 extend in reverse directions parallel to the reference ground 11 and extend toward the reference ground 11 in sequence with the corresponding balanced ports 1202 as ends; Fig.11 and Fig.12 In the structural example, the two oscillators 13 extend in opposite directions parallel to the reference ground 11, extend toward the reference ground 11, and extend towards each other in a direction parallel to the reference ground 11 with the corresponding balanced port 1202 as the end.

[0105] It is worth mentioning that when the distance between the two ends of the corresponding conductor (121 and / or 122) of the non-standard balun 12 with the balanced port 1202 is less than or equal to 3L / 16, the non-standard balun 12 has a structural feature that deviates from the inertial cognition of the standard balun 12P, so that the balanced characteristics of the impedance of the two balanced ports 1202 of the non-standard balun 12 are broken. Therefore, a pair of the dipoles 13 of the dual-element differential antenna 10 of the present invention are preferably set unbalanced to improve the balanced characteristics of the dual-element differential antenna 10.

[0106] Specifically, when the two balanced ports 1202 of the non-standard balun 12 are respectively formed on the first conductor 121 and the second conductor 122, the balanced characteristics of the dual-element differential antenna 10 can be improved by strengthening the coupling strength between the two elements 13 that are fed and connected to the second conductor 122 and the reference ground 11, or by increasing the impedance of the two elements 13 that are fed and connected to the second conductor 122. That is to say, when the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 of the non-standard balun 12 is less than or equal to 3L / 16, a pair of the dipoles 13 are preferably set unbalanced so that the coupling strength between the dipole 13 of the two dipoles 13 that is fed and connected to the second conductor 122 and the reference ground 11 is greater than the coupling strength between the other dipole 13 and the reference ground 11, or the impedance of the dipole 13 of the two dipoles 13 that is fed and connected to the second conductor 122 is greater than the impedance of the other dipole 13, thereby improving the balanced characteristics of the dual-dipole differential antenna 10.

[0107] Corresponding to the accompanying drawings of the present invention Fig.14A and Fig. 14B As shown, based on the comparison of the two structural examples of the present invention, when the coupling strength between the vibrator 13 connected to the second conductor 122 and the reference ground 11 is strengthened, specifically, Fig.14A Based on the structure shown in the figure, by adjusting the length and / or shape of the vibrator 13, when the distance between the end of the vibrator 13 opposite to the corresponding balanced port 1202 and the reference ground 11 is shortened, the specific corresponding Fig. 14BIn the structure shown in the figure, one end of the two oscillators 13 that is fed and connected to the second conductor 122 and is opposite to the corresponding balanced port 1202 is closer to the reference ground 11 than the other end of the other oscillator 13 that is opposite to the corresponding balanced port 1202, so that the coupling strength between the two oscillators 13 that is fed and connected to the second conductor 122 and the reference ground 11 is greater than the coupling strength between the other oscillator 13 and the reference ground 11, that is, an unbalanced setting is formed for the two oscillators 13, thereby improving the balance characteristics of the dual-oscillator differential antenna 10, and the corresponding dual-oscillator differential antenna 10 corresponds to Fig. 14B The radiation pattern shows obvious balanced characteristics.

[0108] Further reference is made to the accompanying drawings of the present invention. Fig.15 As shown, when the impedance of the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 is increased, specifically by adjusting the shape of the vibrator 13, such as increasing the impedance of the vibrator 13 by refining the vibrator 13, the impedance of the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 can also be made greater than the impedance of the other vibrator 13, that is, an unbalanced setting of the two vibrators 13 is formed, thereby improving the balanced characteristics of the dual-element differential antenna 10, and the dual-element differential antenna 10 corresponds to Fig.15 The radiation pattern shows obvious balanced characteristics.

[0109] It is worth mentioning that when the impedance of the vibrator 13 of the two vibrators 13 that is fed and connected to the first conductor 121 is reduced, it is equivalent to increasing the impedance of the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122. Therefore, the impedance of the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 can also be made greater than the impedance of the other vibrator 13, that is, an unbalanced setting of the two vibrators 13 is formed, thereby improving the balanced characteristics of the dual-vibrator differential antenna 10.

[0110] Further reference is made to the accompanying drawings of the present invention. Fig.16As shown, when the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 and the reference ground 11 is strengthened, specifically by adjusting the length and / or shape of the vibrator 13, such as reducing the distance between the vibrator 13 and the reference ground 11 by lengthening the vibrator 13, the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 and the reference ground 11 can also be made greater than the coupling strength between the other vibrator 13 and the reference ground 11, that is, an unbalanced setting of the two vibrators 13 is formed, thereby improving the balanced characteristics of the dual-vibrator differential antenna 10, and the corresponding dual-vibrator differential antenna 10 corresponds to Fig.16 The radiation pattern shows obvious balanced characteristics.

[0111] It is worth mentioning that when the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the first conductor 121 and the reference ground 11 is weakened, it is equivalent to strengthening the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 and the reference ground 11, so that the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 and the reference ground 11 can also be made greater than the coupling strength between the other vibrator 13 and the reference ground 11, that is, an unbalanced setting of the two vibrators 13 is formed, thereby improving the balanced characteristics of the dual-vibrator differential antenna 10.

[0112] That is to say, in some embodiments of the present invention, the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the first conductor 121 and the reference ground 11 can be weakened, specifically by adjusting the length and / or shape of the vibrator 13, such as by lengthening the distance between the end of the vibrator 13 opposite to the corresponding balanced port 1202 and the reference ground 11, or by shortening the vibrator 13 to reduce the coupling area between the vibrator 13 and the reference ground 11. Similarly, the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 and the reference ground 11 can be greater than the coupling strength between the other vibrator 13 and the reference ground 11, that is, an unbalanced setting of the two vibrators 13 is formed, thereby improving the balanced characteristics of the dual-vibrator differential antenna 10.

[0113] In addition, in some other embodiments of the present invention, in order to make the coupling strength between the vibrator 13 of the two vibrators 13 that is fed and connected to the second conductor 122 and the reference ground 11 greater than the coupling strength between the other vibrator 13 and the reference ground 11, the reference ground 11 can be adjusted, such as by adjusting the area of ​​the reference ground 11, or corresponding to Fig.17 By arranging a conductor at a corresponding position on the reference ground 11 so as to equivalently raise the reference ground 11 at that position, the coupling area / distance between the reference ground 11 and the corresponding vibrator 13 is adjusted, so that the coupling strength between the vibrator 13 fed and connected to the second conductor 122 and the reference ground 11 is greater than the coupling strength between the other vibrator 13 and the reference ground 11, that is, an unbalanced setting of the two vibrators 13 is formed, thereby improving the balanced characteristics of the dual-vibrator differential antenna 10.

[0114] Furthermore, when the distance between the two ends of the corresponding conductor (121 and / or 122) having the balanced port 1202 of the non-standard balun 12 is less than or equal to 3L / 16, resulting in the imbalance of the impedance of the two balanced ports 1202 of the non-standard balun 12 being broken, the balanced characteristic of the dual-dipole differential antenna 10 can be improved by unbalanced setting of the length / impedance of the balanced transmission path of the non-standard balun 12. For example, in the state where the two balanced ports 1202 of the non-standard balun 12 are respectively formed on the first conductor 121 and the second conductor 122, an unbalanced setting of the length / impedance of the balanced transmission path of the non-standard balun 12 is formed by unbalanced setting of the length / thickness of the first conductor 121 and the second conductor 122 of the non-standard balun 12, specifically, Fig.18 In the example structure, the lengths of the first conductor 121 and the second conductor 122 of the non-standard balun 12 are unbalancedly set so that the length of the first conductor 121 is less than the length of the second conductor 122, thereby forming an unbalanced setting of the length of the balanced transmission path of the non-standard balun 12, thereby improving the balanced characteristics of the dual-dipole differential antenna 10. The dual-dipole differential antenna 10 corresponds to Fig.18 The radiation pattern shows obvious balanced characteristics.

[0115] In addition, it is worth mentioning that when the distance between the two ends of the corresponding conductor (121 and / or 122) of the non-standard balun 12 with the balanced port 1202 is less than or equal to 3L / 16, resulting in the impedance balance characteristics of the two balanced ports 1202 of the non-standard balun 12 being broken, specifically in the state where the two balanced ports 1202 of the non-standard balun 12 are respectively formed on the first conductor 121 and the second conductor 122, the balance characteristics of the dual-element differential antenna 10 can also be improved by connecting a resistor / capacitor / inductor to the grounded end of the first conductor 121.

[0116] Those skilled in the art will appreciate that the above embodiments are merely examples, wherein features of different embodiments may be combined with each other to obtain implementation methods that are easily conceivable based on the contents disclosed in the present invention but are not explicitly indicated in the drawings.

[0117] It should be understood by those skilled in the art that the embodiments of the present invention described above and shown in the accompanying drawings are only examples and do not limit the present invention. The purpose of the present invention has been fully and effectively achieved. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments, and the embodiments of the present invention may be deformed or modified in any way without departing from the principles.

Claims

1. A non-standard balun that converts single-ended to differential output, characterized by: include: A first conductor and a second conductor coupled to the first conductor, wherein in a state where one end of the first conductor is grounded, the non-standard balun has an unbalanced port and two balanced ports, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are located at the other end of the non-standard balun, wherein the physical length corresponding to one wavelength electrical length of the first conductor and the second conductor is defined as L, and the distance between the two ends of the corresponding conductors having the balanced ports is less than or equal to 3L / 16, wherein when a single-ended signal in an unbalanced state is connected to the unbalanced port of the non-standard balun, the phase difference of the signals output by the two balanced ports is greater than or equal to 150° and less than or equal to 210°, and has a single-ended to differential output characteristic.

2. The non-standard balun for converting single-ended to differential output according to claim 1, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are respectively formed at the other end of the first conductor and the other end of the second conductor.

3. The non-standard balun for converting single-ended to differential output according to claim 2, wherein the first conductor and the second conductor are bent in a discontinuously coupled manner when they are configured as columnar conductors. 4 . The single-ended to differential output non-standard balun according to claim 2 , wherein the first conductor and the second conductor are arranged as two columnar conductors close to each other in a state of being parallel to each other.

5. The non-standard balun for converting single-ended to differential output according to claim 3 or 4, wherein a physical medium is introduced into the coupling space between the first conductor and the second conductor.

6. The non-standard balun for single-ended to differential output according to claim 5, wherein the coupling space between the first conductor and the second conductor is introduced into a solid medium which is an insulating layer sprayed on the surface of the first conductor and / or the second conductor based on a spraying process.

7. The non-standard balun for converting single-ended to differential output according to claim 5, wherein the coupling space between the first conductor and the second conductor is introduced into a solid medium which is an insulating oxide formed on the surface of the first conductor and / or the second conductor by oxidation.

8. The non-standard balun for converting single-ended to differential output according to claim 5, wherein the coupling space between the first conductor and the second conductor is introduced with a physical medium which is an insulating glue bonded between the first conductor and the second conductor.

9. The non-standard balun for converting single-ended to differential output according to claim 5, wherein the coupling space between the first conductor and the second conductor is introduced into a solid medium which is an insulating layer spaced between the first conductor and the second conductor. 10 . The non-standard balun for converting single-ended to differential output according to claim 2 , wherein the first conductor and the second conductor are provided in the form of a ribbon conductor carried on a corresponding circuit board.

11. The non-standard balun for single-ended to differential output according to claim 1, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the other end of the first conductor has a forked structure and has two forked ends, wherein the two balanced ports are respectively formed at the two forked ends of the first conductor.

12. A dual-element differential antenna, characterized in that: include: - reference ground; A non-standard balun, wherein the non-standard balun comprises a first conductor and a second conductor coupled to the first conductor, wherein in a state where one end of the first conductor is electrically connected to the reference ground and is grounded, the non-standard balun has an unbalanced port and two balanced ports, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are located at the other end of the non-standard balun, wherein the physical length corresponding to one wavelength electrical length of the first conductor and the second conductor is defined as L, and the distance between the two ends of the corresponding conductor having the balanced port is less than or equal to 3L / 16; and A pair of oscillators, wherein the two oscillators are respectively fed and connected to the two balanced ports of the non-standard balun and are arranged as conductors extending with the corresponding balanced ports as ends, wherein there is a point on each oscillator where the distance between the oscillator and the corresponding balanced port is greater than or equal to L / 16.

13. The dual-element differential antenna according to claim 12, wherein the unbalanced port is formed at one end of the second conductor and is located at the same end of the non-standard balun as the grounded end of the first conductor, and the two balanced ports are respectively formed at the other end of the first conductor and the other end of the second conductor. 14 . The dipole differential antenna according to claim 13 , wherein the first conductor and the second conductor are provided as two columnar conductors close to each other in a state of being parallel to each other.

15. The double-pole differential antenna according to claim 14, wherein the double-pole differential antenna further comprises a circuit substrate, and a grounding pin extending from the grounded end of the first conductor, and an unbalanced access pin extending from the unbalanced port of the second conductor, wherein the reference ground is carried on the circuit substrate in the form of a copper-clad layer, wherein the first conductor and the second conductor are fixed to the circuit substrate via the grounding pin and the unbalanced access pin respectively, wherein when the first conductor is fixed to the circuit substrate via the grounding pin, the grounded end of the first conductor is electrically connected to the reference ground via the grounding pin and is grounded.

16. The dual-element differential antenna according to claim 15, wherein the ground pin and the unbalanced access pin extend from a grounded end of the first conductor and an unbalanced port of the second conductor in a direction away from each other and in a direction close to the reference ground, respectively. 17 . The two-element differential antenna according to claim 13 , wherein the first conductor and the second conductor are bent in a discontinuously coupled manner in a state where they are provided as columnar conductors.

18. The dual-element differential antenna according to any one of claims 14 to 17, wherein a solid medium is introduced into the coupling space between the first conductor and the second conductor.

19. The dipole differential antenna according to claim 13, wherein the first conductor and the second conductor are provided in the form of strip conductors carried on corresponding circuit boards.

20. The dual-element differential antenna according to any one of claims 12 to 17 and 19, wherein the two elements have opposite initial extension directions with the corresponding balanced ports as ends, and the distance between the balanced ports and the reference ground is greater than or equal to the distance between the other end of the element extending with the balanced port as an end and the reference ground.

21. The dual-element differential antenna according to claim 20, wherein the two elements extend in opposite directions parallel to the reference ground with the corresponding balanced ports as ends.

22. The dual-element differential antenna according to claim 20, wherein the two elements extend in opposite directions in a direction parallel to the reference ground and in a direction toward the reference ground in sequence with the corresponding balanced ports as ends.

23. The dual-element differential antenna according to claim 20, wherein the two elements sequentially extend in opposite directions parallel to the reference ground, extend toward the reference ground, and extend toward each other in a direction parallel to the reference ground with the corresponding balanced port as the end.

24. A dual-element differential antenna according to any one of claims 12 to 17 and 19, wherein the two elements are arranged unbalanced, and the coupling strength between the element fed and connected to the second conductor and the reference ground is greater than the coupling strength between the other element and the reference ground, or the impedance of the element fed and connected to the second conductor is greater than the impedance of the other element.

Images