WO2019128839A1

WO2019128839A1 - Pcb and communication device

Info

Publication number: WO2019128839A1
Application number: PCT/CN2018/122327
Authority: WO
Inventors: 马良; 秦卫星; 刘杰
Original assignee: 华为技术有限公司
Priority date: 2017-12-29
Filing date: 2018-12-20
Publication date: 2019-07-04
Also published as: CN109996388A

Abstract

Provided in the present application are a PCB and a communication device. The PCB comprises a first planar inverted-F antenna and a first wave trap, where a first terminal of the first wave trap is electrically connected to a feed pin of the first planar inverted-F antenna. The PCB of embodiments of the present application, by connecting the wave trap to the feed pin of the IFA, facilitate a ground current of the PCB to be released in the proximity, thus facilitating the elimination of a zero point of a horizontal plane, and enhancing user experience.

Description

PCB board and communication device

The present application claims priority to Chinese Patent Application No. PCT Application No. No. No. No. No. No. No. No. No. No. No. No. No. No. No. No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No No .

Technical field

The present application relates to the field of electronic devices and, more particularly, to a PCB board and communication device.

Background technique

Wireless Fidelity (Wi-Fi) is a technology that can wirelessly connect terminal devices such as personal computers and handheld devices (such as tablets and mobile phones). Wi-Fi devices have become indispensable in our lives. The device, how to make the Wi-Fi device have a better performance experience, puts forward new requirements for the design of the antenna in the Wi-Fi device.

In the existing Wi-Fi equipment, there are two vertical and flat attitudes. The vertical gateway can be placed with a conventional dipole antenna to achieve omnidirectional coverage because the height of both sides is not limited. A wireless access point (AP) or terminal device with a flat attitude is highly limited, and a conventional dipole antenna cannot be placed. Generally, an Inverted-F Antennas (IFA) form antenna is used, and The influence of the current on the printed circuit board (PCB), the antenna pattern has strong directionality, and the water level has more zero points, which affects the user experience. How to eliminate these zeros poses new challenges for antenna designers.

Summary of the invention

The present application provides a PCB board and communication device that helps eliminate the zero point of the horizontal plane by introducing a wavetrap near the feed point, thereby improving the user experience.

In a first aspect, a PCB board is provided, the PCB board includes a first planar inverted-F antenna and a first trap, wherein a first end of the first trap and a feed of the first planar inverted-F antenna The electrical pins are electrically connected.

In some possible implementations, the second end of the first trap is suspended.

The PCB board of the embodiment of the present application helps the PCB ground current to be released by connecting the feeding pin of the IFA antenna to the trap, thereby helping to eliminate the zero point of the water level and improving the user experience.

With reference to the first aspect, in some possible implementation manners of the first aspect, the first end of the first trap is connected to the first end of the switch, and the second end of the switch and the first planar inverted F antenna The feed pins are connected.

The PCB board of the embodiment of the present application can close the switch when the omnidirectional characteristic of the IFA antenna needs to be reached by the switch at the beginning of the trap, so that the PCB ground current is released along the low impedance region; or when the maximum gain of the antenna is required, Turn the switch on to implement switch switching control.

In some possible implementations, the feed pin of the first IFA antenna is connected to the first end of the switch, the second end of the switch is connected to the first end of the inductor, and the second end of the inductor is connected to the first notch. The first end of the device.

With reference to the first aspect, in some possible implementation manners of the first aspect, the first end of the first trap is connected to the first end of the inductor, and the second end of the inductor and the first plane inverted F antenna The feed pins are connected.

The PCB board of the embodiment of the present application contributes to miniaturization of the trap by connecting an inductor at the beginning of the trap.

In conjunction with the first aspect, in some possible implementations of the first aspect, the second end of the first trap is coupled to the first end of the capacitor, and the second end of the capacitor is coupled to ground.

The PCB board of the embodiment of the present application contributes to miniaturization of the trap by connecting a capacitor at the end of the trap.

In conjunction with the first aspect, in some possible implementations of the first aspect, the PCB further includes a second planar inverted-F antenna and a second notch, the first end of the second trap and the second The feed pins of the planar inverted F antenna are connected.

The PCB board of the embodiment of the present application is suitable for a 2*2 multiple input multiple output MIMO device by respectively connecting a notch filter on the feeding pins of the two IFA antennas.

With reference to the first aspect, in some possible implementation manners of the first aspect, a distance between a feeding pin of the first planar inverted-F antenna and a feeding pin of the second planar inverted-F antenna is greater than or equal to the first Distance threshold.

In the PCB board of the embodiment of the present application, when a plurality of IFA antennas are included on the PCB board, a certain distance is maintained between any two IFA antennas to ensure isolation between the two IFA antennas.

In conjunction with the first aspect, in some possible implementations of the first aspect, the horizontal arm direction of the first planar inverted-F antenna is at a predefined angle to the first notch length direction.

In conjunction with the first aspect, in some possible implementations of the first aspect, the length of the first trap is determined according to an operating frequency band of the first planar inverted-F antenna.

In conjunction with the first aspect, in some possible implementations of the first aspect, the first trap is a branched structure or a three-dimensional structure.

In a second aspect, a communication device is provided, the communication device comprising the first aspect and the PCB board in any of the possible implementations of the first aspect.

In conjunction with the second aspect, in some possible implementations of the second aspect, the communication device is a terminal device. In some possible implementations, the communication device is a home gateway device.

DRAWINGS

1 is a physical diagram of a PCB board of an embodiment of the present application.

2 is a schematic view of a PCB board of an embodiment of the present application.

Figure 3 is an S11 curve of an IFA antenna.

Figure 4 shows the current distribution of the PCB at 2.45 GHz.

FIG. 5 is a horizontal plane diagram of an IFA antenna according to an embodiment of the present application.

Figure 6 is a plan view showing the distance of the trap from the ground.

FIG. 7 is another horizontal plane diagram of the IFA antenna of the embodiment of the present application.

Figure 8 is a horizontal plan view of different PCB board sizes in accordance with an embodiment of the present application.

FIG. 9 is a schematic plan view of a PCB board according to an embodiment of the present application.

FIG. 10 is another schematic plan view of a PCB board according to an embodiment of the present application.

FIG. 11 is still another schematic plan view of a PCB board according to an embodiment of the present application.

FIG. 12 is another physical diagram of a PCB board of an embodiment of the present application.

FIG. 13 is still another physical diagram of the PCB board of the embodiment of the present application.

Figure 14 is an S11/S21 curve of two antennas.

Figure 15 is a horizontal view of two antennas.

Figure 16 is another horizontal pattern of the two antennas

17 is another schematic diagram of a PCB board of an embodiment of the present application.

FIG. 18 is still another schematic diagram of a PCB board according to an embodiment of the present application.

Detailed ways

The technical solutions in the present application will be described below with reference to the accompanying drawings.

The technical solution of the embodiment of the present application can be applied to a Wi-Fi device in a flat posture, and can also be applied to other small terminal products, such as a home gateway and a customer premise equipment (CPE).

The terminal device in the embodiment of the present application may refer to a user equipment, an access terminal, a subscriber unit, a subscriber station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a terminal, a wireless communication device, a user agent, or User device. The terminal device may also be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), with wireless communication. Functional handheld devices, computing devices or other processing devices connected to wireless modems, in-vehicle devices, wearable devices, terminal devices in future 5G networks, or in the future evolution of the Public Land Mobile Network (PLMN) The terminal device and the like are not limited in this embodiment of the present application.

1 shows a physical diagram of a PCB board according to an embodiment of the present application. As shown in FIG. 1, the PCB board includes a first planar inverted-F antenna and a first trap, wherein the first trap is One end is electrically connected to a feed pin of the first planar inverted-F antenna.

It should be understood that the first end of the first trap can be soldered to the feed pins of the first planar inverted-F antenna or otherwise electrically connected.

It should also be understood that the second end of the first trap may be suspended or may be connected to the first end of the capacitor, the second end of the capacitor being grounded.

It should also be understood that the trap of the embodiment of the present application may also be referred to as an "associated structure", which functions to bind the ground current of the PCB board.

It should also be understood that the PCB board of the embodiment of the present application helps to tie the ground current of the PCB board through the associated structure by connecting the feed pin and the associated structure.

Specifically, the PCB board consists of a common steel plate insert IFA antenna (one plug is a ground pin (PIN) and the other is a signal feed PIN) and a trap, which is simple and easy to implement.

It should be understood that the first IFA antenna and the first trap can be printed on the PCB or soldered on the PCB, which is not limited in this application.

Optionally, the length of the notch is determined according to a frequency band of the first planar inverted-F antenna.

Optionally, the trap is one quarter wavelength in length.

For example, the length of the trap is a quarter wavelength, wherein the wavelength is calculated as shown in the following formula (1):

Where λ represents the wavelength, υ represents the speed of light, and f represents the operating frequency of the IFA antenna.

2 shows a schematic diagram of a PCB board according to an embodiment of the present application. An effective trap is introduced near the feed pin of the IFA antenna, and the IFA antenna branch L1+L2=L3 (1/4 wavelength) controls the PCB ground. The current distribution helps to improve the omnidirectional characteristics of the IFA antenna.

Next, the performance of the IFA antenna of the embodiment of the present application is tested with the trapping distance of 4 mm (Wavetrap nearby with D=4 mm) in FIG.

The blank portion shown in FIG. 2 is a non-conductive region, the shaded portion is a conductive region (except for the trap), and the "off-ground distance" refers to the length of the non-conductive region between the trap and the conductive region.

Figure 3 shows the S11 curve of the IFA antenna (the abscissa represents the frequency). As can be seen from Figure 3, the IFA antenna can operate at 2.4-2.5 GHz and the bandwidth of the antenna is wide.

Here, the operating frequency of the IFA is determined to be 2.5 GHz, and the speed of light is determined to be 3 × 10 ⁸ m/s, and the wavelength of 120 mm can be obtained, and the quarter air wavelength is 30 mm.

It should be understood that 30mm is the quarter air wavelength of the trap, the medium wavelength is the air wavelength divided by the root dielectric constant, the common PCB medium is FR4, and the dielectric constant is 4.4, then consider a quarter medium. The wavelength is 15mm.

Figure 4 shows the current distribution of the PCB at 2.45GHz. It can be seen from the current distribution that the quarter-wavelength trap conforms to the resonant structure principle and is in a low-impedance state, which causes the PCB current to be released nearby, weakening the original length. The current distribution of the side, and the quarter-wavelength trap and the IFA horizontal arm current are in the same direction, which can produce a horizontal polarization pattern of the lateral dipole, and the longitudinal branch of the remaining IFA antenna can generate a vertical dipole Vertical polarization pattern.

It should be understood that when there is no trap near the IFA antenna feed pin on the PCB, more current is distributed on the edge of the PCB, resulting in more zero planes and a poor overall omnidirectionality of the IFA antenna.

In the PCB board of the embodiment of the present application, a trap is introduced near the IFA antenna feed pin (where the near-end current is strongest), and the trap forms a low-impedance region, so that the current of the PCB board is released near the low-impedance region, weakening The current distribution of the original PCB board edge. Moreover, the quarter branch and the IFA antenna horizontal arm current are in the same direction, producing a horizontal polarization pattern of the lateral dipole, and the remaining IFA longitudinal branch produces a vertical polarization pattern of the vertical dipole, thereby improving the full IFA antenna. To characteristics.

It should be understood that the entire solution of the PCB board of the embodiment of the present application is simple and easy to implement, and no additional cost is introduced.

FIG. 5 shows an IFA antenna horizontal plane pattern according to an embodiment of the present application. As shown in FIG. 5, the minimum gain can reach -1.5 dBi compared to no trap (the PCB only includes the IFA antenna). Increased by 1.5dB and the average level gain increased by 2.2dB.

It should be understood that when there is no trap near the IFA antenna feeding pin on the PCB board, the dipole antenna principle can be used to explain that the unequal-length dipole pattern is controlled by the long arm traction (the edge of the PCB board is more Multi-current), the maximum gain is in the long arm direction, the maximum gain of the antenna is 5.6dBi, the minimum gain of the horizontal plane is -3dBi, there are three zero points, and the overall omnidirectionality is poor.

With reference to FIG. 2 to FIG. 5 above, the performance of the IFA antenna is tested when the trap is 4 mm from the ground. The distance from the trap to the ground is 8 mm (Wavetrap nearby with D=8 mm). The performance of the IFA antenna is tested.

Fig. 6 is a plan view showing the distance of the trap from the ground. As shown in Fig. 6, the ground distance D of the trap is increased from 4 mm to 8 mm in Fig. 2.

FIG. 7 illustrates another horizontal plane pattern of an IFA antenna according to an embodiment of the present application. As shown in FIG. 7, the omnidirectional performance of the IFA antenna is better after the ground distance is increased from 4 mm to 8 mm.

FIG. 8 shows a horizontal plane pattern under different PCB board sizes according to an embodiment of the present application, in which FIG. 8 is a PCB board 1 (x=250 mm/y=128 mm), and a PCB board 2 (x=250 mm/y=200 mm). And the PCB board 3 (x=180mm/y=128mm) is taken as an example. As can be seen from Fig. 8, after adding the trap, the IFA antenna becomes less sensitive to the size of the PCB board, in different sizes. PCB boards can maintain good omnidirectional performance.

It should be understood that the trap of the embodiment of the present application can increase the overall omnidirectional performance of the IFA antenna within a certain range, but the overall omnidirectional performance of the IFA antenna changes after exceeding a certain distance threshold. It tends to be flat.

It should also be understood that the ground clearance of the notch of the embodiment of the present application is related to the size (L1 and L2) of the IFA antenna, and that there are different optimal ground clearances for different sizes of IFA antennas.

Optionally, the first end of the first trap is connected to the first end of the switch, and the second end of the switch is connected to the feed pin of the first planar inverted-F antenna.

It should be understood that the first end and the second end of the first trap are the same, and the feed pin of the first IFA antenna is connected to the first end of the switch, and the second end of the switch is connected to the first notch. The first end of the first trap is suspended; or the first end of the first trap is connected to the first end of the capacitor, and the second end of the capacitor is grounded.

9 shows a schematic plan view of a PCB board (an IFA antenna is not shown in FIG. 9) according to an embodiment of the present application. The start end of the switch can be connected to the beginning of the switch, and the end of the switch is connected to the feed of the IFA antenna. Electrical pin for switching control.

In the PCB board of the embodiment of the present application, the switch is terminated at the beginning of the trap, and the switch can be closed when the omnidirectional characteristic of the IFA antenna needs to be achieved, so that the PCB ground current is released along the low impedance region; or when the maximum gain of the antenna is required, The switch is turned on to implement switching control.

Optionally, the first end of the first trap is connected to the first end of the inductor, and the second end of the inductor is connected to the feed pin of the first planar inverted-F antenna.

10 shows another schematic diagram of a PCB board (the IFA antenna is not shown in FIG. 10) according to an embodiment of the present application. The beginning of the inductor can be connected at the beginning of the trap, and the end of the inductor is connected to the IFA antenna. Feed pin.

It should be understood that after the inductor is added, the size of the trap can be reduced. For example, when there is no inductance, the optimal length of the trap is 20 mm, and after the inductor is added, the length can be reduced to 15 mm. Omnidirectional performance of IFA antennas.

The PCB board of the embodiment of the present application is connected to the inductor at the beginning of the trap, which contributes to miniaturization of the trap.

Optionally, the second end of the first trap is connected to the first end of the capacitor, and the second end of the capacitor is grounded.

FIG. 11 shows a further schematic plan view of the PCB board (the IFA antenna is not shown in FIG. 11) according to an embodiment of the present application. The end of the capacitor may be connected to the end of the trap, and the end of the capacitor is grounded.

It should be understood that the effect of adding the inductor and the capacitor is the same, in order to achieve the miniaturization of the trap.

It should also be understood that the three structures in FIGS. 9, 10, and 11 can be arbitrarily combined. For example, the start of the trap can be connected to the switch and the inductor at the same time, or at the same time, the capacitor can be connected at the end of the trap.

Optionally, the trap is a three-dimensional structure.

FIG. 12 shows another physical diagram of a PCB board in accordance with an embodiment of the present application. As shown in FIG. 12, the trap is a three-dimensional structure.

FIG. 13 illustrates still another physical diagram of a PCB board according to an embodiment of the present application. As shown in FIG. 13, the PCB board further includes a second planar inverted-F antenna and a second notch, wherein the second notch The first end of the device is electrically connected to the feed pin of the second planar inverted-F antenna, and the second end of the second notch is grounded.

Specifically, the PCB board is converted from a single antenna to a dual antenna based on FIG. 1, and is suitable for a 2*2 Multiple Input Multiple Output (MIMO) device.

It should be understood that the number of IFA antennas of the PCB is not limited to one or two, and there may be more IFA antennas and traps, which are not enumerated here.

Optionally, a distance between a feeding pin of the first planar inverted-F antenna and a feeding pin of the second planar inverted-F antenna is greater than or equal to a first distance threshold.

Specifically, when multiple IFA antennas are included on the PCB, a certain distance should be maintained between any two IFA antennas to ensure isolation between the two IFA antennas.

Figure 14 shows the S11/S21 curve of the two antennas (S parameter represents the S parameter). As can be seen from Figure 14, the two antennas can cover 2.4 GHz and the isolation is greater than 14 dBi, which is satisfactory.

Fig. 15 shows a horizontal pattern of the two antennas. As can be seen from Fig. 15, both the first IFA antenna and the second IFA antenna have better omnidirectional characteristics.

Table 1 shows the performance test results of two antennas. One AP product is selected, the PCB size is 180*125*1mm, and the Wi-Fi antenna unit is in the form of a steel insert IFA. The antenna length is 25mm and the height is 15mm. 16 illustrates another horizontal pattern of two antennas in accordance with an embodiment of the present application. For simplicity, the Wi-Fi antenna selects a single frequency mode operating at 2.4 GHz. The measured gain is 3dBi, the minimum gain of the horizontal plane is -2.86dBi, and the omnidirectionality is better.

Table 1 Two antenna performance test results

It should be understood that the efficiency in Table 1 is the ratio of the IFA antenna input energy to the output energy, and the gain is a 3D gain.

It should also be understood that the horizontal pattern of Figures 5, 7, 8, and 15 is a simulation result diagram, and the horizontal pattern shown in Figure 16 is a horizontal pattern of the physical test.

In the embodiment of the present application, a trap is introduced near the feeding pin of the IFA antenna, and the low impedance state is presented nearby, so that the current of the PCB ground is released, and the current distribution of the long side is weakened. The trap and the IFA horizontal arm current are in the same direction, producing a horizontal polarization pattern of the lateral dipole. The vertical branch of the remaining IFA is generated, and the vertical polarization pattern of the vertical dipole is used; the omnidirectional effect is achieved; the entire scheme is simple, and no additional cost is introduced.

17 shows another schematic diagram of a PCB board according to an embodiment of the present application. Compared to FIG. 2, the introduced trap is a branch or a groove, and its orientation can be the same as the IFA horizontal arm according to design requirements. The dipole-like omnidirectional characteristic; it can also control its angle or length so that it exhibits multi-polarization characteristics.

FIG. 18 shows still another schematic diagram of a PCB board according to an embodiment of the present application, which can realize miniaturization of the trap by means of bending, loading, three-dimensional and structural conformal.

The embodiment of the present application further provides a communication device, which includes any one of the above PCB boards.

Optionally, the communication device is a terminal device.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods to implement the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present application.

A person skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the system, the device and the unit described above can refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

In the several embodiments provided by the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

The functions may be stored in a computer readable storage medium if implemented in the form of a software functional unit and sold or used as a standalone product. Based on such understanding, the technical solution of the present application, which is essential or contributes to the prior art, or a part of the technical solution, may be embodied in the form of a software product, which is stored in a storage medium, including The instructions are used to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like, which can store program codes. .

The foregoing is only a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application. It should be covered by the scope of protection of this application. Therefore, the scope of protection of the present application should be determined by the scope of the claims.

Claims

A PCB board, characterized in that the PCB board comprises a first planar inverted-F antenna and a first trap, wherein

The first end of the first trap is electrically connected to a feed pin of the first planar inverted-F antenna.
The PCB board according to claim 1, wherein a first end of the first trap is connected to a first end of the switch, and a second end of the switch is opposite to the first plane inverted F antenna Feed pins are connected.
The PCB board according to claim 1 or 2, wherein the first end of the first trap is connected to the first end of the inductor, and the second end of the inductor is inverted from the first plane The feed pins of the antenna are connected.
The PCB board according to any one of claims 1 to 3, wherein the second end of the first trap is connected to the first end of the capacitor, and the second end of the capacitor is grounded.
The PCB board according to any one of claims 1 to 4, wherein the PCB board further comprises a second planar inverted-F antenna and a second trap, the first end of the second trap Connected to a feed pin of the second planar inverted-F antenna.
The PCB board according to claim 5, wherein a distance between a feed pin of the first planar inverted-F antenna and a feed pin of the second planar inverted-F antenna is greater than or equal to a first distance threshold .
The PCB board according to any one of claims 1 to 6, wherein a horizontal arm direction of the first planar inverted-F antenna is at a predefined angle with respect to a length direction of the first trap.
The PCB board according to any one of claims 1 to 7, wherein the length of the first trap is determined according to an operating frequency band of the first planar inverted-F antenna.
The PCB board according to any one of claims 1 to 8, wherein the first trap is a branched structure or a three-dimensional structure.
A communication device, characterized in that the communication device comprises the PCB board according to any one of claims 1-9.
The communication device according to claim 10, characterized in that said communication device is a terminal device.