An open-slot antenna pair and antenna terminal

Abstract

The present invention discloses an open-slot antenna pair and an antenna terminal, which relates to the field of wireless communication and is used to transmit or receive signals, including a first IFA antenna and a second IFA antenna, and the first IFA antenna and the second IFA antenna are arranged tail to tail on a metal base plate, and a bandpass circuit is arranged between the metal base plate and the upper arm of the second IFA antenna, and the bandpass circuit can be coupled with the first IFA antenna through the upper arm of the second IFA antenna. Based on this, the bandpass circuit can provide bandpass filtering in the third frequency band to filter out the signal of the third frequency band, that is, the first IFA antenna and the second IFA antenna are decoupled to ensure the isolation between the first IFA antenna and the second IFA antenna, thereby reducing the distance between the two antennas. It can be seen that in the present application, the space occupancy of the antenna pair can be reduced while avoiding interference between the antennas, thereby reducing the volume of the antenna pair.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications, and in particular to an open-slot antenna pair and an antenna terminal. Background Art

[0002] In the design of terminal antennas with limited volume, based on the requirement of making the terminal thin and light, dual antennas need to be integrated in a limited space, which results in poor isolation between the two antennas and affects the wireless performance of the terminal antenna. Summary of the invention

[0003] The object of the present invention is to provide an open-slot antenna pair and an antenna terminal, which can reduce the space occupied by the antenna pair while avoiding interference between antennas, thereby reducing the volume of the antenna pair.

[0004] To solve the above technical problems, the present invention provides an open-slot antenna pair, including a first IFA antenna and a second IFA antenna, wherein the first IFA antenna and the second IFA antenna are arranged tail to tail on a metal base plate, and the distance between the tail end of the first IFA antenna and the tail end of the second IFA antenna is less than a preset distance; the first IFA antenna operates in a first frequency band, and the second IFA antenna operates in a second frequency band; and further comprising:

[0005] A bandpass circuit is provided between the metal base plate and the upper arm of the second IFA antenna, and is coupled to the first IFA antenna through the upper arm of the second IFA antenna, and the distance between the bandpass circuit and the tail end of the second IFA antenna is smaller than the distance between the feeder of the second IFA antenna and its own tail end;

[0006] The bandpass circuit is used to provide bandpass filtering in a third frequency band to filter out signals in the third frequency band; the third frequency band is between the first frequency band and the second frequency band.

[0007] Preferably, the bandpass circuit comprises an isolation chip, a first filter circuit, a second filter circuit and a bandpass filter circuit;

[0008] A first end of the first filtering circuit is connected to the upper arm of the second IFA antenna, and a second end is connected to the first end of the isolation chip, for filtering out clutter in the second frequency band;

[0009] The first end of the second filtering circuit is coupled to the first IFA antenna through the upper arm of the second IFA antenna, and the second end is connected to the second end of the isolation chip, for filtering out clutter in the first frequency band;

[0010] A ground terminal of the first filter circuit and a ground terminal of the second filter circuit are connected to the metal bottom plate;

[0011] The bandpass filter circuit is arranged at the bandpass end of the isolation chip, and is used for providing bandpass filtering in the third frequency band to filter out the signal in the third frequency band.

[0012] Preferably, the first filter circuit comprises a first sub-filter capacitor and a first sub-filter inductor;

[0013] A first end of the first sub-filter capacitor is connected to the upper arm of the second IFA antenna and a first end of the first sub-filter inductor, and a second end is connected to the second end of the isolation chip;

[0014] The second end of the second sub-filter inductor is a ground end.

[0015] Preferably, the second filtering circuit comprises a second sub-filtering capacitor, a third sub-filtering capacitor, a second sub-filtering inductor and a third sub-filtering inductor;

[0016] The first end of the second sub-filter capacitor is connected to the second end of the isolation chip and the first end of the second sub-isolation inductor, and the second end is connected to the first end of the third sub-filter capacitor and the first end of the third sub-filter inductor;

[0017] The second end of the third sub-filter inductor is coupled to the first IFA antenna through the upper arm of the second IFA antenna;

[0018] The second end of the second sub-filter inductor and the second end of the third sub-filter capacitor are grounded.

[0019] Preferably, the bandpass filter circuit comprises a bandpass filter capacitor and a bandpass filter inductor;

[0020] The first end of the bandpass filter capacitor is connected to the first side of the bandpass end of the isolation chip, and the second end is connected to the first end of the bandpass filter inductor;

[0021] The second end of the bandpass filter inductor is connected to the second side of the bandpass end of the isolation chip.

[0022] Preferably, the capacitance of the bandpass filter capacitor is 1 pF, and the inductance of the bandpass filter inductor is 1 nH.

[0023] Preferably, the first IFA antenna and the second IFA antenna are arranged at positions corresponding to the preset wavelength modes of the metal base plate to excite the preset wavelength modes of the ground.

[0024] Preferably, the first IFA antenna and the second IFA antenna form a double L-shaped metal middle frame branch.

[0025] Preferably, the first frequency band is a 5G UHB frequency band, and the second frequency band is a WiFi 2.4G frequency band.

[0026] Preferably, the first IFA antenna and the bandpass filter circuit constitute a loop antenna.

[0027] In order to solve the above technical problem, the present invention provides an antenna terminal, comprising the open-slot antenna pair as described above.

[0028] The present application provides an open-slot antenna pair and an antenna terminal, which relates to the field of wireless communications and is used to transmit or receive signals, including a first IFA antenna and a second IFA antenna, and the first IFA antenna and the second IFA antenna are arranged end to end on a metal base plate, and a bandpass circuit is arranged between the metal base plate and the upper arm of the second IFA antenna, and the bandpass circuit can be coupled to the first IFA antenna through the upper arm of the second IFA antenna. Based on this, the bandpass circuit can provide bandpass filtering in the third frequency band to filter out the signal of the third frequency band, that is, decouple the first IFA antenna and the second IFA antenna, ensure the isolation between the first IFA antenna and the second IFA antenna, and thus reduce the distance between the two antennas. It can be seen that in the present application, the space occupied by the antenna pair can be reduced while avoiding interference between the antennas, thereby reducing the volume of the antenna pair. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 A schematic diagram of the structure of an open-slot antenna pair provided by the present invention;

[0031] Figure 2 A schematic diagram of a double-branch loop current provided by the present invention;

[0032] Figure 3 A bandwidth schematic diagram of an open-slot antenna pair provided by the present invention;

[0033] Figure 4 A schematic diagram of the isolation of an open-slot antenna pair provided by the present invention;

[0034] Figure 5 A schematic structural diagram of a bandpass circuit provided by the present invention;

[0035] Figure 6 A schematic diagram of current distribution of a first IFA antenna provided by the present invention;

[0036] Figure 7 This is a schematic diagram of the current distribution of the second IFA antenna provided by the present invention. DETAILED DESCRIPTION

[0037] The core of the present invention is to provide an open-slot antenna pair and an antenna terminal, which can reduce the space occupied by the antenna pair while avoiding interference between antennas, thereby reducing the volume of the antenna pair.

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of an open-slot antenna pair provided by the present invention includes a first IFA antenna 01 and a second IFA antenna 02, wherein the first IFA antenna 01 and the second IFA antenna 02 are arranged end to end on a metal base plate 04, and the distance between the tail end of the first IFA antenna 01 and the tail end of the second IFA antenna 02 is less than a preset distance; the first IFA antenna 01 operates in a first frequency band, and the second IFA antenna 02 operates in a second frequency band; and further includes:

[0040] A bandpass circuit 03 is provided between the metal base plate 04 and the upper arm of the second IFA antenna 02, and is coupled to the first IFA antenna 01 through the upper arm of the second IFA antenna 02, and the distance between the bandpass circuit 03 and the tail end of the second IFA antenna 02 is smaller than the distance between the feed line of the second IFA antenna 02 and its own tail end;

[0041] The bandpass circuit 03 is used to provide bandpass filtering in the third frequency band to filter out the signal in the third frequency band; the third frequency band is between the first frequency band and the second frequency band.

[0042] Considering the high volume requirement for antenna terminals, the prior art generally uses methods such as orthogonal routing, grounding or decoupling neutralization line method, and decoupling with phase shifters to reduce interference between antennas in order to reduce the volume of the antenna.

[0043] Among them, when using the orthogonal routing method to reduce interference between antennas, the routing direction of the main antenna of the dual-antenna terminal is perpendicular to the routing direction of the slave antenna, so that the orthogonality of the antenna polarization of the slave antenna in the receiving direction of the main antenna is strengthened, thereby reducing the energy absorbed by the slave antenna of the radiation signal of the main antenna, and the energy absorbed by the main antenna of the radiation signal of the slave antenna is also reduced accordingly, thereby improving the isolation between the antennas. However, this method causes the antenna pair to be in a small space, and is subject to the obstruction of large-sized components in the structural stack, which makes it difficult to achieve good orthogonality in the routing, and the decoupling effect is greatly limited.

[0044] Secondly, when using the grounding or decoupling neutralization line method, a non-conductive line parallel to the top frame and two antenna slot openings for connecting the non-conductive line and the top frame are provided, and the two antenna slot openings are respectively the first antenna slot opening and the second antenna slot opening, and a grounding point is embedded in the first antenna slot opening. In this way, firstly, adding a grounding point or a neutralization line will affect the modal distribution of the frequency band, causing the radiation efficiency of the entire antenna system to change. Secondly, the grounding or neutralization line measures also require circuit board space, which is difficult to implement in a compact stacking environment.

[0045] When a phase shifter is used for decoupling, it is located between the multi-channel feed unit and the antenna array unit. The isolation adjustment unit includes at least four channels and at least one coupling subunit. One end of the at least four channels is respectively connected to the output end of the multi-channel feed unit, and the other end of the at least four channels is respectively connected to an antenna array unit. The coupling subunit is located on at least two channels of the isolation adjustment unit and is used to connect at least two channels so that the signals in at least two channels are coupled to each other. This method has high requirements for the RF link and requires the design of a complex phase shifter, which increases the complexity of the design and makes it difficult to control design changes.

[0046] In this embodiment, a bandpass circuit 03 is additionally added between the upper arm of the second antenna and the metal base plate 04. The bandpass circuit 03 provides bandpass filtering at the third frequency to filter out the signal of the third frequency band. The first IFA antenna 01 can work normally in the first frequency band, and the second IFA antenna 02 can work normally in the second frequency band. Since the third frequency band is between the first frequency band and the second frequency band, the first frequency band and the second frequency band will not interfere with each other. The distance between the tail end of the first IFA antenna 01 and the tail end of the second IFA antenna 02 can be less than the preset distance, so as to reduce the space occupied by the first IFA antenna 01 and the second IFA antenna 02, and reduce the volume of the open-slot antenna pair.

[0047] The preset distance may be, but is not limited to, 1 mm, and may be set according to actual needs of the user.

[0048] As a preferred embodiment, the first IFA antenna 01 and the second IFA antenna 02 form a double L-shaped metal middle frame branch, that is, the first IFA antenna 01 and the second IFA antenna 02 are both L-shaped to increase the signal radiation range.

[0049] In addition, as a preferred embodiment, the first frequency band is the 5G UHB frequency band, and the second frequency band is the WiFi 2.4G frequency band. Of course, this application does not limit this, and the first frequency band and the second frequency band can be set according to user needs.

[0050] It should also be noted that, as a preferred embodiment, the first IFA antenna 01 and the bandpass circuit 03 constitute a loop antenna. Figure 2 , Figure 2 A schematic diagram of a double-branch loop current provided by the present invention, wherein the first IFA antenna 01 forms a loop antenna by reusing the upper arm branches of the second IFA antenna 02 and the bandpass circuit 03, thereby increasing the radiation area of ​​the first IFA antenna 01 and improving the bandwidth of the first IFA antenna 01. Please refer to Figure 3 , Figure 3 A bandwidth diagram of an open-slot antenna pair provided by the present invention, wherein S1,1 is the bandwidth of the first IFA antenna 01, and S2,2 is the bandwidth of the second IFA antenna 02. It can be seen that the first IFA antenna 01 increases the bandwidth by about 3.7 GHz.

[0051] Please refer to Figure 4 , Figure 4 A schematic diagram of the isolation of an open-slot antenna pair provided by the present invention. It can be seen that the isolation of S2,1, that is, the power transmitted from the first IFA antenna 01 to the second IFA antenna 02, has an isolation of -55dB at around 3.7GHz. Since the smaller the isolation, the smaller the interference between the two, it is sufficient to ensure that the first IFA antenna 01 and the second IFA antenna 02 will not affect each other.

[0052] In summary, in the present application, the space occupied by the antenna pair can be reduced while avoiding interference between antennas, thereby reducing the volume of the antenna pair.

[0053] Based on the above embodiments:

[0054] Please refer to Figure 5 , Figure 5 A schematic structural diagram of a bandpass circuit provided by the present invention.

[0055] As a preferred embodiment, the bandpass circuit 03 includes an isolation chip, a first filter circuit, a second filter circuit and a bandpass filter circuit;

[0056] A first end of the first filter circuit is connected to the upper arm of the second IFA antenna 02, and a second end is connected to the first end of the isolation chip, for filtering out clutter in the second frequency band;

[0057] The first end of the second filtering circuit is coupled to the first IFA antenna 01 through the upper arm of the second IFA antenna 02, and the second end is connected to the second end of the isolation chip, for filtering out clutter in the first frequency band;

[0058] The grounding terminal of the first filter circuit and the grounding terminal of the second filter circuit are connected to the metal bottom plate 04;

[0059] The bandpass filter circuit is arranged at the bandpass end of the isolation chip, and is used for providing bandpass filtering in the third frequency band to filter out the signal in the third frequency band.

[0060] In this embodiment, when the bandpass circuit 03 is set, the bandpass circuit 03 includes an isolation chip, a first filtering circuit, a second filtering circuit and a bandpass filtering circuit, wherein the first filtering circuit filters out the clutter of the second IFA antenna 02 to prevent the second IFA antenna 02 from being interfered by the clutter during operation; the second filtering circuit filters out the clutter of the first IFA antenna 01 to prevent the first IFA antenna 01 from being interfered by the clutter during operation; and the bandpass filtering circuit filters out the signal of the third frequency band to prevent the first IFA antenna 01 and the second IFA antenna 02 from interfering with each other, thereby improving the efficiency of the open-slot antenna.

[0061] As a preferred embodiment, the first filter circuit includes a first sub-filter capacitor C1 and a first sub-filter inductor L1;

[0062] A first end of the first sub-filter capacitor C1 is connected to the upper arm of the second IFA antenna 02 and the first end of the first sub-filter inductor L1, and a second end is connected to the second end of the isolation chip;

[0063] The second end of the second sub-filter inductor L2 is a ground end.

[0064] The first filter circuit in this embodiment is composed of a pair of filter capacitors and inductors, wherein the capacitance of the first sub-filter capacitor C1 can be but is not limited to 1.9pF, and the inductance of the first sub-filter inductor L1 can be but is not limited to 1.2nH, which can achieve filtering of the clutter in the second frequency band.

[0065] As a preferred embodiment, the second filtering circuit includes a second sub-filter capacitor C2, a third sub-filter capacitor C3, a second sub-filter inductor L2 and a third sub-filter inductor L3;

[0066] The first end of the second sub-filter capacitor C2 is connected to the second end of the isolation chip and the first end of the second sub-isolation inductor, and the second end is connected to the first end of the third sub-filter capacitor C3 and the first end of the third sub-filter inductor L3;

[0067] The second end of the third sub-filter inductor L3 is coupled to the first IFA antenna 01 through the upper arm of the second IFA antenna 02;

[0068] The second end of the second sub-filter inductor L2 and the second end of the third sub-filter capacitor C3 are grounded.

[0069] The second filtering circuit in this embodiment is composed of two pairs of filter capacitors and inductors, wherein the capacitance of the second sub-filter capacitor C2 and the third sub-filter capacitor C3 can be but is not limited to 0.3pF, the inductance of the second sub-filter inductor L2 can be but is not limited to 22nH, and the inductance of the third sub-filter inductor L3 can be but is not limited to 1.5nH, which can achieve filtering of clutter in the first frequency band.

[0070] Among them, since the bandpass circuit 03 increases the bandwidth of the first IFA antenna 01, by additionally providing a pair of filter capacitors and inductors, it is possible to filter out clutter of two bandwidths.

[0071] As a preferred embodiment, the bandpass filter circuit includes a bandpass filter capacitor C4 and a bandpass filter inductor L4;

[0072] A first end of the bandpass filter capacitor C4 is connected to a first side of the bandpass end of the isolation chip, and a second end is connected to a first end of the bandpass filter inductor L4;

[0073] The second end of the bandpass filter inductor L4 is connected to the second side of the bandpass end of the isolation chip.

[0074] The bandpass filter capacitor C4 in this embodiment includes a pair of filter capacitors and inductors, and the bandpass filter circuit is arranged at the bandpass end of the isolation chip, which can filter out the signal of the third frequency band to avoid mutual interference between the first IFA antenna 01 and the second IFA antenna 02.

[0075] As a preferred embodiment, the capacitance of the bandpass filter capacitor C4 may be but not limited to 1pF, and the inductance of the bandpass filter inductor L4 may be but not limited to 1nH. Of course, here, the third frequency band of 3.6GHz is taken as an example, and the specific capacitance of the bandpass filter capacitor C4 and the inductance of the bandpass filter inductor L4 can be set according to the signal of the third frequency band set by the user.

[0076] As a preferred embodiment, the first IFA antenna 01 and the second IFA antenna 02 are disposed at positions corresponding to the preset wavelength modes of the metal base plate 04 to excite the preset wavelength modes of the ground.

[0077] It should also be noted that when the first IFA antenna 01 and the second IFA antenna 02 are arranged on the metal base plate 04, they need to be arranged at the positions corresponding to the preset wavelength modes. Figure 6 and Figure 7 , Figure 6 A schematic diagram of current distribution of a first IFA antenna provided by the present invention, Figure 7 The second IFA antenna current distribution diagram provided by the present invention is based on which a preset wavelength mode, such as a 1.5 wavelength mode, can be excited to enable the first IFA antenna 01 to be fed at the current peak position.

[0078] It should be noted that Figure 2 , Figure 6 and Figure 7 The denser the arrows are, the higher the current density is.

[0079] In summary, a bandpass circuit is used in this implementation, which is equivalent to a capacitor, to offset the inherent inductance of the open-slot antenna pair to achieve high isolation, while forming a 1-wavelength differential mode signal, increasing the bandwidth, and not affecting the working state of low-frequency band WIFI, and pointing out the optimal feeding position.

[0080] The present invention also provides an antenna terminal, comprising the open-slot antenna pair as described above.

[0081] For the introduction of the antenna terminal provided by the present invention, please refer to the above embodiments, and the present invention will not be described in detail here.

[0082] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0083] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An open-slot antenna pair, comprising a first IFA antenna and a second IFA antenna, characterized in that: The first IFA antenna and the second IFA antenna are arranged tail to tail on the metal base plate, and the distance between the tail end of the first IFA antenna and the tail end of the second IFA antenna is less than a preset distance; the first IFA antenna operates in a first frequency band, and the second IFA antenna operates in a second frequency band; and further comprising: A bandpass circuit is provided between the metal base plate and the upper arm of the second IFA antenna, and is coupled to the first IFA antenna through the upper arm of the second IFA antenna, and the distance between the bandpass circuit and the tail end of the second IFA antenna is smaller than the distance between the feeder of the second IFA antenna and its own tail end; The bandpass circuit is used to provide bandpass filtering in a third frequency band to filter out signals in the third frequency band; the third frequency band is between the first frequency band and the second frequency band; The bandpass circuit includes an isolation chip, a first filter circuit, a second filter circuit and a bandpass filter circuit; A first end of the first filtering circuit is connected to the upper arm of the second IFA antenna, and a second end is connected to the first end of the isolation chip, for filtering out clutter in the second frequency band; The first end of the second filtering circuit is coupled to the first IFA antenna through the upper arm of the second IFA antenna, and the second end is connected to the second end of the isolation chip, for filtering out clutter in the first frequency band; A ground terminal of the first filter circuit and a ground terminal of the second filter circuit are connected to the metal bottom plate; The bandpass filter circuit is arranged at the bandpass end of the isolation chip, and is used for providing bandpass filtering in the third frequency band to filter out the signal in the third frequency band.

2. The open-slot antenna pair according to claim 1, characterized in that: The first filter circuit includes a first sub-filter capacitor and a first sub-filter inductor; A first end of the first sub-filter capacitor is connected to the upper arm of the second IFA antenna and a first end of the first sub-filter inductor, and a second end is connected to the second end of the isolation chip; The second end of the first sub-filter inductor is a ground end.

3. The open-slot antenna pair according to claim 1, characterized in that: The second filtering circuit includes a second sub-filtering capacitor, a third sub-filtering capacitor, a second sub-filtering inductor and a third sub-filtering inductor; The first end of the second sub-filter capacitor is connected to the second end of the isolation chip and the first end of the second sub-filter inductor, and the second end is connected to the first end of the third sub-filter capacitor and the first end of the third sub-filter inductor; The second end of the third sub-filter inductor is coupled to the first IFA antenna through the upper arm of the second IFA antenna; The second end of the second sub-filter inductor and the second end of the third sub-filter capacitor are grounded.

4. The open-slot antenna pair according to claim 1, characterized in that: The bandpass filter circuit includes a bandpass filter capacitor and a bandpass filter inductor; The first end of the bandpass filter capacitor is connected to the first side of the bandpass end of the isolation chip, and the second end is connected to the first end of the bandpass filter inductor; The second end of the bandpass filter inductor is connected to the second side of the bandpass end of the isolation chip.

5. The open-slot antenna pair as claimed in claim 4, characterized in that: The capacitance of the bandpass filter capacitor is 1 pF, and the inductance of the bandpass filter inductor is 1 nH.

6. The open-slot antenna pair according to claim 1, wherein: The first IFA antenna and the second IFA antenna are arranged at positions corresponding to the preset wavelength modes of the metal base plate to excite the preset wavelength modes of the ground.

7. The open-slot antenna pair according to claim 1, characterized in that: The first IFA antenna and the second IFA antenna form a double L-shaped metal middle frame branch.

8. The open-slot antenna pair according to claim 1, wherein: The first frequency band is the 5G UHB frequency band, and the second frequency band is the WiFi 2.4G frequency band.

9. The open-slot antenna pair according to claim 1, wherein: The first IFA antenna and the bandpass filter circuit constitute a loop antenna.

10. An antenna terminal, characterized in that: Comprising an open-slot antenna pair as described in any one of claims 1-9.

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