Multiband antenna

Abstract

A multiband antenna includes a coaxial cable and a printed circuit board. The printed circuit board comprises a first side surface and a second side surface. The first side faces the second side. The first side surface comprises a radiation part, a feed-in part and a first grounding part. The radiation part comprises a first radiation arm, a second radiation arm and a third radiation arm which are connected with one another. The feed-in part is connected with the radiation part and the coaxial cable. The first grounding part is connected with the coaxial cable. The second side surface comprises a first end, a second end and a coupling part. The coupling part and the third radiation arm are overlapped in the vertical direction. The vertical direction is perpendicular to the first side and the second side. The first radiation arm, the second radiation arm and the third radiation arm excite a first frequency band. The third radiation arm and the coupling part excite a second frequency band. The third radiation arm is connected to the main board of the machine through the feed-in part and the coaxial cable so as to excite a third frequency band. The utility model provides a multiband antenna structure, which can greatly save the space in the device, can radiate multiband antennas at the same time, and has good antenna radiation characteristics.

Description

Technical Field

[0001] This case relates to an antenna structure. Specifically, this case relates to a multi-band antenna structure. Background Art

[0002] As mobile communication technology gradually matures, the transmission speed of mobile communication networks is faster. However, the problem faced is that the frequency bands that wireless communication devices need to support also increase. In addition, the current trend in the size of wireless communication devices is to be thin, light, and portable. The industry hopes to use the same antenna to support all frequency bands to save costs. Therefore, how to use the same antenna to support a wide range of frequency bands is an important issue faced in this field.

[0003] Therefore, there are still many defects in the above technologies, and it is necessary for practitioners in this field to develop other suitable multi-band antennas. Summary of the Utility Model

[0004] One aspect of this case relates to a multi-band antenna. The multi-band antenna includes a coaxial cable and a printed circuit board. The printed circuit board includes a first side and a second side. The first side is opposite to the second side. The first side includes a radiation portion, a feeding portion, and a first grounding portion. The radiation portion includes a first radiation arm, a second radiation arm, and a third radiation arm. The first radiation arm, the second radiation arm, and the third radiation arm are connected to each other. The feeding portion is connected to the radiation portion and the coaxial cable. The first grounding portion is connected to the coaxial cable. The second side includes a first end, a second end, and a coupling portion. The coupling portion is disposed at the first end. The coupling portion and the third radiation arm overlap in the vertical direction. The vertical direction is perpendicular to the first side and the second side of the printed circuit board. The first radiation arm, the second radiation arm, and the third radiation arm excite a first frequency band. The third radiation arm and the coupling portion excite a second frequency band. The third radiation arm is connected to the main board of the machine through the feeding portion and the coaxial cable to excite a third frequency band.

[0005] In some embodiments, the first side of the multi-band antenna further includes a frequency modulation circuit. The frequency modulation circuit is soldered between the radiation portion and the feeding portion and is used to adjust the first frequency band, the second frequency band, and the third frequency band corresponding to the type of the machine.

[0006] In some embodiments, the frequency modulation circuit includes at least one of an inductor and a capacitor.

[0007] In some embodiments, the length of the first radiation arm is less than the length of the second radiation arm. The length of the second radiation arm is less than the length of the third radiation arm.

[0008] In some embodiments, the first side surface includes a first end and a second end. The third radiation arm includes a first impedance matching portion, a second impedance matching portion, and a third impedance matching portion. The arrangement order from the first end to the second end of the first side surface is the first impedance matching portion, the second impedance matching portion, and the third impedance matching portion in sequence.

[0009] In some embodiments, the first impedance matching portion, the second impedance matching portion, and the third impedance matching portion are respectively mirror-symmetrical about the central axis of the third radiation arm.

[0010] In some embodiments, the length of the coupling portion of the second side surface is between the second impedance matching portion and the first radiation arm and the second radiation arm.

[0011] In some embodiments, the coaxial cable includes a central conductor layer and an outer conductor layer. The outer conductor layer of the coaxial cable is connected to the main board of the machine to perform a short circuit, so as to excite a third frequency band together with the feeding portion and the third radiation arm.

[0012] In some embodiments, the printed circuit board further includes a plurality of vias. The plurality of vias are located in the first grounding portion. The second side surface further includes a second grounding portion. The first grounding portion is connected to the second grounding portion and the outer conductor layer of the coaxial cable through the plurality of vias.

[0013] In some embodiments, the feeding portion is connected to the central conductor layer of the coaxial cable.

[0014] This case provides a design of a multi-band antenna, which can greatly save the space in the device, can simultaneously radiate antennas of multiple frequency bands, and has good antenna radiation characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Referring to the embodiments in the following paragraphs and the following drawings, the content of this case can be better understood:

[0016] Figure 1 FIG. is a schematic diagram of a machine and a multi-band antenna according to some embodiments of this case;

[0017] Figure 2 FIG. is a schematic structural diagram of a multi-band antenna according to some embodiments of this case;

[0018] Figure 3 FIG. is a schematic diagram of the connection between a multi-band antenna and a machine according to some embodiments of this case;

[0019] Figure 4 FIG. is a schematic diagram of two side surfaces of a multi-band antenna according to some embodiments of this case; and

[0020] Figure 5 FIG. is a curve graph of the antenna radiation efficiency of a multi-band antenna according to some embodiments of this case.

[0021] Reference numerals:

[0022] 100: Multi-band antenna

[0023] 900: Machine

[0024] 910: Main board

[0025] 920: Heat sink

[0026] 930: Antenna bracket

[0027] B: Printed circuit board

[0028] C C: Coaxial cable

[0029] S1: First side

[0030] S2: Second side

[0031] R: Radiation part

[0032] R 1 to R 3: Radiation arms

[0033] T 1: T-shaped structure

[0034] I 11 to I 12, I 21 to I 22, I 31 to I 32: Impedance matching parts

[0035] A 1: Frequency modulation circuit

[0036] F 1: Feeding part

[0037] C 1: Coupling part

[0038] A X: Central axis

[0039] H 1 to H 4: Via holes

[0040] G 1 to G 3: Grounding parts

[0041] E C: Line segment

[0042] W 1 to W 2: Solder joints

[0043] L 1 to L 2: Lengths Detailed implementation manners

[0044] The spirit of this case will be clearly described below with reference to the drawings and detailed descriptions. After understanding the embodiments of this case, any person with ordinary knowledge in the technical field to which this case pertains can make changes and modifications based on the techniques taught by this case, and it does not deviate from the spirit and scope of this case.

[0045] The terms used in this document are only for describing specific embodiments and are not intended to limit the present case. Singular forms such as "a", "this", "herein", "the present", and "the", as used herein, also include plural forms.

[0046] Regarding the terms "comprising", "including", "having",

[0047] "containing", etc., used in this document, are all open-ended terms, meaning including but not limited to.

[0048] Regarding the terms used in this document, unless otherwise specified, they generally have their ordinary meanings in the field, in the context of the present case, and in the specific context. Some of the terms used to describe the present case will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in the description of the present case.

[0049] Figure 1 FIG. is a schematic diagram of a multi-band antenna 100 and a machine 900 according to some embodiments of the present case. In some embodiments, referring to Figure 1 , the machine 900 includes a main board 910, a heat sink 920, and an antenna bracket 930. The multi-band antenna 100 is disposed on the antenna bracket 930 and is connected to the main board 910.

[0050] In some embodiments, the multi-band antenna 100 can be disposed in a Customer Premise Equipment (CPE). The multi-band antenna 100 of the customer premise equipment is used to receive mobile communication signals (such as 4G, 5G, etc.) or wired broadband signals, and convert them into local area network signals for the machine 900 to use. The multi-band antenna 100 of the customer premise equipment is used to convert the electrical signals of the machine 900 into radio frequency signals for transmission.

[0051] To make the structure of the multi-band antenna 100 easier to understand, please refer to Figure 2 . Figure 2 FIG. is a schematic structural diagram of a multi-band antenna 100 according to some embodiments of the present case. The multi-band antenna 100 includes a coaxial cable CC and a printed circuit board B. The printed circuit board B includes a first side S1 and a second side S2. Please refer to Figure 2 , the left drawing is the first side S1 of the printed circuit board B. The first side S1 is a top view of the front side of the printed circuit board B. The right drawing is the second side S2 of the printed circuit board B. The second side S2 is a bottom view of the back side of the printed circuit board B. The first side S1 is opposite to the second side S2. Both the first side S1 and the second side S2 include a first end (i.e., the upper part of the drawing) and a second end (i.e., the lower part of the drawing).

[0052] In some embodiments, the coaxial cable CC includes a central conductor layer, a plastic insulating layer, an outer conductor layer, and a protective layer (not shown in the figure). The central conductor layer is typically a conductive copper wire. The plastic insulating layer is used as an insulator or dielectric. The outer conductor layer is typically a mesh conductor (such as copper or an alloy). The protective layer is typically a material that insulates from the outside world.

[0053] In some embodiments, the first side S1 of the printed circuit board B includes a radiation portion R, a feeding portion F1, a grounding portion G1, and a grounding portion G2. In the direction from the first end to the second end of the first side S1, the radiation portion R, the feeding portion F1, the grounding portion G1, and the grounding portion G2 are arranged in sequence.

[0054] The radiation portion R includes radiation arms R1, R2, and R3. The radiation arms R1, R2, and R3 are connected to each other. The shapes of the radiation arms R1 and R2 are generally in an M shape. The shape of the radiation arm R3 is generally in a triangular shape, and the vertex of the triangle is connected to the middle of the M shape at a position similar to the letter V in the English alphabet. The lengths and areas of the radiation arms R1, R2, and R3 are all different. In some embodiments, the length of the radiation arm R1 is less than the length of the radiation arm R2. The length of the radiation arm R2 is less than the length of the radiation arm R3.

[0055] In some embodiments, the radiation arm R3 includes a plurality of impedance matching portions (such as impedance matching portions I11, I12, I21, I22, I31, and I32) and a T-shaped structure T1.

[0056] In the arrangement order from the first end to the second end of the first side S1 of the printed circuit board B, the impedance matching portions (such as impedance matching portions I11 and I12), the impedance matching portions (such as impedance matching portions I21 and I22), and the impedance matching portions (such as impedance matching portions I31 and I32) are arranged in sequence. The impedance matching portions I11 and I12 are mirror-symmetrical about the central axis AX. The impedance matching portions I21 and I22 are mirror-symmetrical about the central axis AX. The impedance matching portions I31 and I32 are mirror-symmetrical about the central axis AX.

[0057] Below the radiation part R is the feeding part F1. The feeding part F1 extends downward in a substantially straight bar shape. On both sides of the extended end section of the feeding part F1 are the grounding part G1 and the grounding part G2 respectively. The extended end section of the feeding part F1 is connected to the coaxial cable CC. The grounding part G1 includes a plurality of via holes (such as via hole H1 and via hole H2). The grounding part G2 includes a plurality of via holes (such as via hole H3 and via hole H4). The via holes H1 to H4 of the grounding part G1 and the grounding part G2 can be respectively connected to the second side S2 of the printed circuit board B.

[0058] In some embodiments, the second side S2 of the printed circuit board B includes a coupling part C1 and a grounding part G3. The via holes H1 to H4 of the grounding part G1 and the grounding part G2 can be respectively connected to the grounding part G3 on the second side S2 of the printed circuit board B. The coupling part C1 extends in a substantially straight bar shape from the first end (i.e., the upper part of the drawing) to the second end (i.e., the lower part of the drawing) of the second side S2. The coupling part C1 and the radiation arm R3 overlap in the vertical direction, and the vertical direction is perpendicular to the first side S1 and the second side S2 of the printed circuit board B. The length of the coupling part C1 has a limiting condition, which will be described in a subsequent paragraph in conjunction with the frequency modulation mechanism.

[0059] In some embodiments, please refer to Figure 1 and Figure 2 , the first side S1 of the printed circuit board B further includes a frequency modulation circuit A1. The frequency modulation circuit A1 is soldered between the radiation part R and the feeding part F1 and is used to adjust the different frequency bands excited by the radiation part R (i.e., the radiation arm R1, the radiation arm R2, and the radiation arm R3) corresponding to the type of the machine 900. In some embodiments, the frequency modulation circuit A1 includes at least one of a capacitor and an inductor.

[0060] Currently, the size trend of wireless communication devices is towards being thin, light, and portable. In order to save costs in the industry, it is hoped that the same antenna can be used to support all frequency bands. Therefore, how to use the same antenna to support a wide range of frequency bands depends on those skilled in the art.

[0061] To make the frequency modulation mechanism of the multi-band antenna 100 easier to understand, please also refer to Figure 2 and Figure 4 , Figure 3 is a schematic diagram of the connection between the multi-band antenna 100 shown according to some embodiments of the present case and Figure 1 the main board 910 of the machine 900. Figure 4 is a schematic diagram of both sides of the multi-band antenna 100 shown according to some embodiments of the present case. Please refer to Figure 2 and Figure 3, the multi-band antenna 100 can be used to excite multiple frequency bands in the 5G NR (New Radio) frequency band to support communication services and device requirements of different frequency bands. The 5G NR (New Radio) frequency band is mainly divided into the low frequency band (600 MHz to 900 MHz), the middle frequency band (1 GHz to 2 GHz), the high frequency band (3 GHz to 6 GHz), and the extremely high frequency band (above 24 GHz). The low frequency band is mainly used to transmit communication signals over longer distances. The middle frequency band and the high frequency band are mainly used for mission-critical applications and enhanced mobile broadband. The extremely high frequency band is mainly used to support the requirements of extreme bandwidth.

[0062] In some embodiments, the multi-band antenna 100 of this case is mainly applied to the low frequency band, the middle frequency band, and the high frequency band in the 5G NR frequency band. In some embodiments, the low frequency band excited by the multi-band antenna 100 is approximately 617 - 960 MHz. The middle frequency band excited by the multi-band antenna 100 is approximately 1.71 - 2.36 GHz. The high frequency band excited by the multi-band antenna 100 is approximately 3.3 - 4.2 GHz.

[0063] Please refer to Figures 2 to 3 , the excitation mechanism of the low frequency band of the multi-band antenna 100 is mainly to strip the outer skin of the coaxial cable CC (i.e., the protective layer mentioned in the previous paragraph) to expose the outer conductive layer of the coaxial cable CC (i.e., the line segment EC of the coaxial cable CC), and connect the outer conductive layer of the coaxial cable CC to the main board 910 of the machine 900 by welding, and then perform a short circuit. The electrical signal is transmitted to the feeding part F1 through the coaxial cable CC, and then transmitted to the radiation arm R3 of the upper radiation part R through the feeding part F1, and then upward along the central axis AX to the T-shaped structure T1, the impedance matching part I11, and the impedance matching part I12 of the radiation arm R3 to perform impedance matching in the low frequency band, so as to convert the electrical signal into a radio frequency signal in the low frequency band through this path for radiation. It should be noted that the purpose of this short circuit design is to enhance the radiation efficiency of the low frequency band of the antenna and have better return loss.

[0064] Please refer to Figures 2 to 4, the excitation mechanism of the middle frequency band of the multi-band antenna 100 is mainly to transmit the electrical signal to the feeding part F1 through the coaxial cable CC, and then transmit it to the radiation arm R3 of the upper radiation part R through the feeding part F1, and conduct it along both sides of the radiation arm R3 to the impedance matching parts I11, I12, I21 and I22, and through the coupling part C1 on the second side S2 of the printed circuit board B to perform impedance matching of the middle frequency band, so as to convert the electrical signal into a radio frequency signal of the middle frequency band through this path for radiation. In some embodiments, the length of the coupling part C1 can be adjusted between the shortest length L1 and the longest length L2 according to actual needs. The shortest length L1 of the coupling part C1 shall not be shorter than the impedance matching parts I21 and I22 on the first side S1. The longest length L2 of the coupling part C1 shall not exceed the radiation arms R1 and R2 on the first side S1.

[0065] Please refer to Figures 2 to 4 , the excitation mechanism of the high frequency band of the multi-band antenna 100 is mainly to transmit the electrical signal to the feeding part F1 through the coaxial cable CC, and then transmit it to the radiation arms R1, R2 of the upper radiation part R and the impedance matching parts I31 and I32 of the radiation arm R3 to perform impedance matching of the high frequency band, so as to convert the electrical signal into a radio frequency signal of the high frequency band through this path for radiation. It should be noted that the different designs of the lengths or areas of the radiation arms R1 and R2 are intended to combine the radio frequency signals of the high frequency band to support a wider frequency range.

[0066] In some embodiments, please refer to Figure 1 , Figure 2 and Figure 4 , since the radio frequency signal of the low frequency band mainly relies on the short circuit design of the main board 910 of the machine 900, the multi-band antenna 100 of this case can be designed correspondingly according to the type of the machine 900 Figure 2 the capacitance value of the capacitor or the inductance value of the inductor in the frequency modulation circuit A1 in the middle frequency modulation circuit A1 to further adjust the radio frequency signal of the low frequency band. In some embodiments, the frequency modulation circuit A1 can also be designed as a zero ohm resistor to adjust the radio frequency signal of the low frequency band. The frequency modulation circuit A1 can be determined whether to be designed between the feeding part F1 and the radiation part R according to actual needs.

[0067] In some embodiments, please refer to Figure 2 and Figure 4 , the central conductor layer of the coaxial cable CC can be connected to the solder point W1 of the feeding part F1. The outer conductor layer of the coaxial cable CC can be connected to the solder point W2 of the grounding part G1 and connected to the grounding part G3 on the second side S2 through the via hole H2. In practice, welding treatment is performed at the via holes H1 to H4, and the detailed welding conditions here cannot be directly confirmed by the naked eye.

[0068] Figure 5 It is the antenna radiation efficiency curve graph of the multi-band antenna 100 illustrated according to some embodiments of this case. Please refer to Figure 5 , for the multi-band antenna 100 of this case, the radiation efficiency in the low frequency band (i.e., 617 - 960 MHz) is approximately between 55% and 90%, and its average radiation efficiency is approximately 74%. For the multi-band antenna 100 of this case, the radiation efficiency in the middle frequency band (i.e., 1.71 - 2.36 GHz) is approximately between 25% and 90%, and its average radiation efficiency is approximately 61%. For the multi-band antenna 100 of this case, the radiation efficiency in the high frequency band (i.e., 3.3 - 4.2 GHz) is approximately between 68% and 80%, and its average radiation efficiency is approximately 74%. Since the average radiation efficiency of the multi-band antenna 100 of this case in the above frequency bands is greater than 60%, it has good antenna radiation characteristics.

[0069] According to the foregoing embodiments, this case provides a multi-band antenna structure, which can greatly save the space inside the device, can radiate antennas of multiple frequency bands simultaneously, and has good antenna radiation characteristics.

[0070] Although this case is disclosed in detail as above, this case does not exclude other feasible implementation manners. Therefore, the protection scope of this case shall be subject to what is defined by the attached patent application scope, rather than being limited by the foregoing embodiments.

[0071] For those skilled in the art, without departing from the spirit and scope of this case, various modifications and refinements can be made to this case. Based on the foregoing embodiments, all modifications and refinements made to this case are also covered by the protection scope of this case.

Claims

1. A multi-band antenna, characterized in that: Include: Coaxial cable; and Printed circuit board, including: A first side surface and a second side surface, wherein the first side surface is opposite to the second side surface; The first side comprises: A radiation portion, comprising a first radiation arm, a second radiation arm and a third radiation arm, wherein the first radiation arm, the second radiation arm and the third radiation arm are connected to each other; a feeding portion connected to the radiating portion and the coaxial cable; and A first grounding portion connected to the coaxial cable; The second side comprises: a first end and a second end; and a coupling portion disposed at the first end, wherein the coupling portion and the third radiating arm overlap in a vertical direction, wherein the vertical direction is perpendicular to the first side surface and the second side surface of the printed circuit board; The first radiation arm, the second radiation arm and the third radiation arm excite a first frequency band, the third radiation arm and the coupling part excite a second frequency band, and the third radiation arm is connected to the mainboard of the machine through the feeding part and the coaxial cable to excite a third frequency band.

2. The multi-band antenna according to claim 1, wherein: The first aspect further comprises: The frequency modulation circuit is welded between the radiation part and the feeding part, and is used to adjust the first frequency band, the second frequency band and the third frequency band according to the type of the machine.

3. The multi-band antenna according to claim 2, wherein: The frequency modulation circuit includes at least one of an inductor and a capacitor.

4. The multi-band antenna according to claim 1, wherein: The length of the first radiating arm is smaller than the length of the second radiating arm, wherein the length of the second radiating arm is smaller than the length of the third radiating arm.

5. The multi-band antenna according to claim 1, wherein: The first side surface includes a first end and a second end, wherein the third radiating arm includes a first impedance matching portion, a second impedance matching portion, and a third impedance matching portion, and the arrangement order from the first end to the second end of the first side surface is the first impedance matching portion, the second impedance matching portion, and the third impedance matching portion.

6. The multi-band antenna according to claim 5, characterized in that: The first impedance matching portion, the second impedance matching portion, and the third impedance matching portion are mirror-symmetrical about the central axis of the third radiation arm.

7. The multi-band antenna according to claim 5, wherein: The length of the coupling portion of the second side surface is between the second impedance matching portion and the first radiation arm and the second radiation arm.

8. The multi-band antenna according to claim 1, wherein: The coaxial cable includes a central conductor layer and an outer conductor layer, wherein the outer conductor layer of the coaxial cable is connected to the mainboard of the machine to be short-circuited, so as to excite the third frequency band with the feeding part and the third radiation arm.

9. The multi-band antenna according to claim 8, wherein: The printed circuit board further includes a plurality of via holes, the plurality of via holes are located at the first grounding portion, wherein the second side surface further includes a second grounding portion, and the first grounding portion is connected to the second grounding portion and the outer conductor layer of the coaxial cable through the plurality of via holes.

10. The multi-band antenna according to claim 8, wherein: The feeding portion is connected to the central conductor layer of the coaxial cable.

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