CN113659307A - Antenna device and electronic apparatus - Google Patents

Abstract

The application provides an antenna device and an electronic apparatus. The antenna device includes: a plurality of antenna elements; a plurality of decoupling networks in one-to-one correspondence with the plurality of antenna elements; each decoupling network is provided with an input port, an output port, a first connecting port and a second connecting port, a feeder line is connected between the output port and the corresponding antenna unit, and the input port is used for being connected with the radio frequency chip; a first decoupling transmission line connected between first connection ports of adjacent decoupling networks; a second decoupling transmission line connected between second connection ports of adjacent decoupling networks. The application can improve the isolation between the antenna device and the electronic equipment.

Description

Antenna device and electronic apparatus

Technical Field

The application relates to the technical field of antenna decoupling, in particular to an antenna device and electronic equipment adopting the same.

Background

An antenna can efficiently transmit and receive electromagnetic waves, and is an indispensable important component in a wireless communication system. However, with the advancement of scientific technology, it is difficult for a single antenna to meet the increasing performance requirements. In order to solve the problems of poor directivity, low radiation gain and the like of a single antenna, a plurality of antenna units with the same radiation characteristics can be arranged according to a certain geometric structure to form the array antenna, so that the radiation performance of the array antenna is enhanced, and a flexible directional diagram is generated to meet the requirements of different scenes.

Disclosure of Invention

One aspect of the present application provides an antenna device, including: a plurality of antenna elements; a plurality of decoupling networks in one-to-one correspondence with the plurality of antenna elements; each decoupling network is provided with an input port, an output port, a first connecting port and a second connecting port, a feeder line is connected between the output port and the corresponding antenna unit, and the input port is used for being connected with the radio frequency chip; a first decoupling transmission line connected between first connection ports of adjacent decoupling networks; a second decoupling transmission line connected between second connection ports of adjacent decoupling networks.

In another aspect, the present application also provides an electronic device, comprising: a housing; the display screen assembly is connected with the shell and forms an accommodating space with the shell; the radio frequency chip is arranged in the accommodating space; and the antenna device is at least partially arranged in the accommodating space. The antenna device includes: a plurality of spaced apart antenna elements; a plurality of decoupling networks in one-to-one correspondence with the plurality of antenna units, wherein each decoupling network has an input port, an output port, a first connection port, and a second connection port; a first feeder is connected between the output port and the corresponding antenna unit, and a second feeder is connected between the input port and the radio frequency chip; a first decoupling transmission line connected between first connection ports of adjacent decoupling networks; a second decoupling transmission line connected between second connection ports of adjacent decoupling networks.

According to the multi-antenna system, the first decoupling network and the second decoupling network are arranged between two adjacent antenna units, and the first decoupling transmission line and the second decoupling transmission line are connected between the first decoupling network and the second decoupling network, so that one part of signals emitted from the feed source are transmitted to the antenna units through the first decoupling network, and the other part of signals are transmitted to the second decoupling network through the first decoupling network and the first decoupling transmission line and the second decoupling transmission line to reach the adjacent antenna units, so that coupling between the two antenna units is counteracted to a certain extent, and the isolation degree of the multi-antenna system is improved. Furthermore, the concept of a decoupling network is introduced below the antenna units, the structure of the array antenna units does not need to be changed, and the coupling degree between the antenna units can be adjusted by only configuring the lengths of the first decoupling transmission line and the second decoupling transmission line and the scattering parameters (namely, S parameters) of the four-port network, so that the mutual coupling between the antenna units can be reduced, the scanning angle is expanded, and the scanning gain is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without inventive effort, wherein:

fig. 1 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

fig. 2 is a schematic diagram of a decoupling principle for an array antenna according to an embodiment of the present application;

fig. 3 is a schematic diagram of a decoupling structure for an array antenna according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a first decoupling network of an embodiment of the present application;

fig. 5 is a schematic structural diagram of a second decoupling network of an embodiment of the present application;

fig. 6 is a schematic flow chart of a decoupling method for an array antenna according to an embodiment of the present application;

fig. 7 is a schematic perspective view of an electronic device according to an embodiment of the present application;

fig. 8 is a perspective view of an antenna device according to an embodiment of the present application;

fig. 9 is a top view of the antenna arrangement of fig. 8;

fig. 10 is a bottom view of the antenna device of fig. 8;

fig. 11 is a partial schematic view of the antenna arrangement of fig. 10 showing the arrangement of the first and second decoupling networks of the antenna arrangement and the first and second decoupling transmission lines connected therebetween;

fig. 12 is a schematic view of a layered structure of an antenna device according to an embodiment of the present application, in which two antenna elements are shown;

fig. 13 is a schematic view of an antenna arrangement according to another embodiment of the present application;

fig. 14 shows a comparison curve of coupling coefficients between two antenna elements in the antenna device according to the embodiment of the present application before and after connecting the decoupling network;

fig. 15 shows a comparison curve of reflection coefficients of antenna elements in the antenna device of the embodiment of the present application before and after connection of the decoupling network;

fig. 16 shows a graph of the radiation performance of the antenna arrangement of an embodiment of the application when the beam is scanned to 0 ° before the decoupling network is connected;

fig. 17 shows a graph of the radiation performance of the antenna arrangement of the embodiment of the application when the beam is scanned to 0 ° after connection of the decoupling network;

fig. 18 shows a graph of the radiation performance of the antenna arrangement of an embodiment of the application when the beam is scanned to 45 deg. before the decoupling network is connected;

fig. 19 shows a graph of the radiation performance of the antenna arrangement of an embodiment of the application when the beam is scanned to 45 ° after connection of the decoupling network;

fig. 20 shows a graph of the radiation performance of the antenna arrangement of an embodiment of the application when the beam is scanned to 50 ° before the decoupling network is connected;

fig. 21 shows a graph of the radiation performance of the antenna arrangement of an embodiment of the application when the beam is scanned to 50 ° after connection of the decoupling network;

fig. 22 shows a graph of the radiation performance of the antenna arrangement of the embodiment of the present application when the beam is scanned to 55 ° after the decoupling network is connected.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The array antenna, especially the small-distance array antenna, has the problem of strong mutual coupling. Mutual coupling between antenna elements greatly affects the matching characteristics and spatial radiation characteristics of the antenna elements and the array thereof, and is expressed in the following points.

(1) Directional diagram: the distribution of the currents in the antenna elements is changed under the mutual coupling, resulting in that part of the radiated energy is further coupled to other antenna elements, wherein a part of the coupled energy is absorbed by the terminating load and consumed, and another part of the energy is radiated again. Therefore, the pattern of the antenna element is distorted. The termination load is a parameter equivalent to the rear end of the antenna feed source; when drawing an equivalent circuit, the entire back end of the antenna feed may be replaced with a resistor and may be referred to as a terminating load.

(2) Input impedance: due to the mutual coupling, the input impedance of the antenna elements in the array changes and is different from the input impedance of the antenna elements in an isolated environment, so that the matching condition of the antenna elements in each array is different and the matching characteristic is affected.

(3) Gain: there are heat loss and reflection loss caused by unmatched characteristic impedance in the antenna unit, so that the radiation power of the antenna unit is smaller than the emission power, and the reflection coefficient is changed under the action of mutual coupling, so that the gain of the antenna unit is affected.

In the related art, in order to solve the influence of the mutual coupling effect on the characteristics of the directional pattern, the input impedance, the gain, and the like of the antenna unit, the following five methods are generally adopted: a Defected Ground Structure (DGS-Defected Ground Structure) Decoupling method, a neutral Line (NLT-neutral Line technology) Decoupling method, a Band-stop filtering Decoupling method, an Electromagnetic Band Gap (EBG) Decoupling method, and a Metamaterial Decoupling Method (MDT).

However, the above methods are all directed to the research of the method for eliminating the coupling between the antenna elements, and the coupling effect between the antenna elements cannot be precisely defined and controlled.

The application provides an electronic device, an array antenna of the electronic device can self-define the coupling effect among antenna units, and realize the control of radiation patterns of the antenna units through the design of the coupling effect, such as widening a scanning angle, improving scanning gain, eliminating a scanning blind area and the like.

The electronic device may be a terminal device such as a mobile phone, a tablet computer, a PDA (Personal Digital Assistant), a Point of Sales (POS), a vehicle-mounted computer, and a Customer Premise Equipment (CPE). The present application is described below with a mobile phone as an example.

As shown in fig. 1, the handset 100 may include: RF (Radio Frequency) circuitry 101, memory 102, a Central Processing Unit (CPU) 103, peripheral interfaces 104, audio circuitry 105, speakers 106, a power management chip 107, an input/output (I/O) subsystem 108, a touch screen 109, other input/control devices 110, and an external port 111, which communicate via one or more communication buses or signal lines 112.

It should be understood that the illustrated handset is merely one example of an electronic device and that the handset 100 may have more or fewer components than shown in the figures, may combine two or more components, or may have a different configuration of components. The various components shown in the figures may be implemented in hardware, software, or a combination of hardware and software, including one or more signal processing and/or application specific integrated circuits.

The components of the handset 100 will be described in detail with reference to fig. 1.

The Radio Frequency (RF) circuit 101 is mainly used to establish communication between the mobile phone and the wireless network (i.e., network side), and implement data reception and transmission between the mobile phone and the wireless network. Such as sending and receiving short messages, e-mails, etc. Specifically, the RF circuit 101 receives and transmits RF signals, which are also referred to as electromagnetic signals, and the RF circuit 101 converts electrical signals into electromagnetic signals or vice versa and communicates with a communication network and other devices through the electromagnetic signals. The RF circuitry 101 may include known circuitry for performing these functions including, but not limited to, an antenna system with an antenna array, an RF transceiver, one or more amplifiers, a tuner, one or more oscillators, a digital signal processor, a CODEC (CODEC) chipset, a Subscriber Identity Module (SIM), and so forth.

The memory 102 may be accessed by the CPU 103, the peripheral interface 104, and the like, and the memory 102 may include high speed random access memory and may also include non-volatile memory, such as one or more magnetic disk storage devices, flash memory devices, or other volatile solid state storage devices.

The central processing unit 103 executes various functional applications and data processing of the electronic device by executing software programs and modules stored in the memory 102.

Peripheral interface 104 may connect input and output peripherals of the device to CPU 103 and memory 102.

The I/O subsystem 108 may connect input and output peripherals on the device, such as a touch screen 109 and other input/control devices 110, to the peripheral interface 104. I/O subsystem 108 may include a display controller 1081 and one or more input controllers 1082 for controlling other input/control devices 110. Where one or more input controllers 1082 receive electrical signals from or transmit electrical signals to other input/control devices 110, the other input/control devices 110 may include physical buttons (push buttons, rocker buttons, etc.), dials, slide switches, joysticks, click wheels. It is worth noting that the input controller 1082 may be connected with any one of the following: a keyboard, an infrared port, a USB interface, and a pointing device such as a mouse.

The touch screen 109 is an input interface and an output interface between the user terminal and the user, and displays visual output to the user, which may include graphics, text, icons, video, and the like.

The display controller 1081 in the I/O subsystem 108 receives electrical signals from the touch screen 109 or sends electrical signals to the touch screen 109. The touch screen 109 detects a contact on the touch screen, and the display controller 1081 converts the detected contact into an interaction with a user interface object displayed on the touch screen 109, that is, implements a human-computer interaction, and the user interface object displayed on the touch screen 109 may be an icon for running a game, an icon networked to a corresponding network, or the like. It is worth mentioning that the device may also comprise a light mouse, which is a touch sensitive surface that does not show visual output, or an extension of the touch sensitive surface formed by the touch screen.

The audio circuit 105 is primarily used to receive audio data from the peripheral interface 104, convert the audio data to an electrical signal, and send the electrical signal to the speaker 106.

The speaker 106 is used to convert voice signals received by the handset 100 from the wireless network through the RF circuit 101 into sound and play the sound to the user.

The power management chip 107 is used for supplying power and managing power to the hardware connected to the CPU 103, the I/O subsystem 108, and the peripheral interface 104.

The following is directed to an array antenna in an antenna system of the RF circuitry 101 of the electronic device. The array antenna typically includes a plurality of closely arranged antenna elements. In at least two adjacent antenna units, each antenna unit is connected with the feed source through a decoupling network. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise.

The present embodiment describes the present application by taking two adjacent antenna elements 10 and 20 as an example. As shown in fig. 2, it is a schematic diagram of a decoupling principle for an array antenna according to an embodiment of the present application, where the array antenna includes an adjacent antenna unit 10 and an adjacent antenna unit 20. The radiation characteristics of the antenna element 10 and the antenna element 20 may be the same or different. The antenna unit 10 may receive an excitation current from a feed source (radio frequency transceiver) of the electronic device, and after amplification, filtering, matching and tuning, the antenna unit 10 is excited to resonate at a corresponding frequency, so as to generate an electromagnetic wave signal at the corresponding frequency, and the electromagnetic wave signal at the same frequency as the free space is coupled to realize signal transmission. The antenna unit 10 may also couple electromagnetic wave signals with the same frequency from free space under the excitation of the excitation signal, so as to form an induced current on the antenna unit 10, and the induced current is filtered and amplified and then enters the rf transceiver.

The decoupling networks corresponding to the two adjacent antenna units 10 and 20 are connected to each other, wherein the antenna unit 10 corresponds to the first decoupling network 31, and the antenna unit 20 corresponds to the second decoupling network 31'. The first and second decoupling networks 31, 31' are each four-port networks. The first decoupling network 31 has an input port (a) to which a feed is connected₁,b₁) An output port (a) connected to the antenna unit 10₂,b₂) And a first connection port (a) for connecting a second decoupling network 31₃,b₃) And a second connection port (a)₄,b₄). Second decoupling networkThe network 31 ' has an input port (a ') connected to the feed source '₁,b’₁) And an output port (a ') connected to the antenna unit 20'₂,b’₂) And a first connection port (a ') for connection to a first decoupling network 31'₃,b’₃) And a second connection port (a'₄,b’₄). Length d₁May form the output port (a)₂,b₂) And has a characteristic impedance Z₀(ii) a Length d₂May form the output port (a'₂,b’₂) And has a characteristic impedance Z₀. Length d₃Is connected to a first connection port (a) of a first decoupling network 31₃,b₃) First connection port (a ') to a second decoupling network 31'₃,b’₃) And has a characteristic impedance Z₃(ii) a Length d₄Is connected to a second connection port (a) of the first decoupling network 31₄,b₄) Second connection port (a ') to a second decoupling network 31'₄,b’₄) And has a characteristic impedance Z₄. In addition, a₁，a₂，a’₁，a’₂，a₃，a₄，a’₃，a’₄Is the amplitude of the incident voltage wave, b₁，b₂，b’₁，b’₂，b₃，b₄，b’₃，b’₄Is the reflected voltage wave amplitude. It should be noted that the "input port" and the "output port" in the embodiment of the present application are named only from the perspective of the antenna unit 10 transmitting signals. It is understood that the antenna unit 10 can also receive signals, and in this case, the "output port" can be used as an input port, and the "input port" can be used as an output port, that is, the names of the "input port" and the "output port" in this application are not limited to the attributes of the ports. It should also be noted that the length d in fig. 2 is₁Also shows a characteristic impedance Z₀The two transmission lines correspond to the same wire in real object; likewise, length d₂To be transmitted toLine, length d₃And a first decoupled transmission line of length d₄Should also be understood as such. Characteristic impedance Z₃Characteristic impedance Z₄Can be set to the characteristic impedance Z₀Are equal. In addition, the characteristic impedance Z₀Usually predetermined, for example, to 50 Ω.

As shown in fig. 3, it is a schematic diagram of a decoupling structure for an array antenna according to an embodiment of the present application, wherein at least a first decoupling network 31, a second decoupling network 31', and a first decoupling transmission line 33 and a second decoupling transmission line 34 connected therebetween may constitute the decoupling structure for an array antenna of the present application. In addition, the decoupling structure and the array antenna connected thereto may also form the antenna device of the present application.

Examples of the first decoupling network 31 corresponding to the antenna element 10 in fig. 3 and 4 are described in detail below. It will be appreciated that the second decoupling network 31' corresponding to the antenna element 20 may be identical to the first decoupling network 31 corresponding to the antenna element 10.

In particular, as shown in fig. 3 and 4, the first decoupling network 31 is a four-port network. In one embodiment, the four port network is a directional coupler, which may include a directional coupler body 310 and four transmission lines extending from the directional coupler body 310. The four transmission lines include a first transmission line 311, a second transmission line 312, a third transmission line 313, and a fourth transmission line 314. In addition, the first connection port (a) of the directional coupler₃,b₃) Can be a coupled port or an isolated port; correspondingly, the second connection port (a) of the directional coupler₄,b₄) May be an isolated port or a coupled port.

The directional coupler body 310 may include a fifth transmission line 315, a sixth transmission line 316, a seventh transmission line 317, and an eighth transmission line 318. The fifth transmission line 315, the sixth transmission line 316, the seventh transmission line 317 and the eighth transmission line 318 are sequentially connected end to form a loop.

Wherein a first end of the first transmission line 311 is connected with a first end of the fifth transmission line 315, and a second end of the first transmission line 311 forms an input port connected with the feed 40. A first end of the second transmission line 312 is connected to a second end of the fifth transmission line 315, the second end of the second transmission line 312 forming an output port connected to the antenna unit 10. A first end of the third transmission line 313 is connected to a first end of the seventh transmission line 317 and a second end of the third transmission line 313 forms a first connection port connected to a first end of the first decoupling transmission line 33. A first end of the fourth transmission line 314 is connected to a second end of the seventh transmission line 317 and the second end of the fourth transmission line 314 forms a second connection port connected to a first end of the second decoupling transmission line 34. It is noted that the first and second ends of a transmission line as described herein refer to the two opposite ends of the transmission line.

The third and fourth transmission lines 313 and 314 may be designed to have a short length, for example, the length of the third and fourth transmission lines 313 and 314 can be connected only to the first and second decoupling transmission lines 33 and 34 without having a redundant length. This can reduce the influence on the length design of the first and second decoupling transmission lines 33, 34.

The characteristic impedance of fifth transmission line 315 and seventh transmission line 317 may be designed to be Z₁The characteristic impedance of the sixth transmission line 316 and the eighth transmission line 318 can be designed to be Z₂. Additionally, the lengths of fifth transmission line 315, sixth transmission line 316, seventh transmission line 317, and eighth transmission line 318 may each be set to (1/4) λ, where λ is the wavelength.

As shown in fig. 3 and 5, the second decoupling network 31' corresponding to the antenna unit 20 may be the same as the first decoupling network 31 described above. In particular, the second decoupling network 31' is a four-port network. In one embodiment, the four port network is a directional coupler, which may include a directional coupler body 310 'and four transmission lines extending from the directional coupler body 310'. The four transmission lines include a first transmission line 311 ', a second transmission line 312', a third transmission line 313 'and a fourth transmission line 314'. Additionally, a first connection port (a ') of the directional coupler'₃,b’₃) Can be a coupled port or an isolated port; correspondingly, the second connection port (a ') of the directional coupler'₄,b’₄) May be an isolated port or couplingAnd (6) combining ports.

The directional coupler body 310 ' may include a fifth transmission line 315 ', a sixth transmission line 316 ', a seventh transmission line 317 ', and an eighth transmission line 318 '. The fifth transmission line 315 ', the sixth transmission line 316', the seventh transmission line 317 'and the eighth transmission line 318' are connected end to end in sequence to form a loop.

Wherein a first end of the first transmission line 311 'is connected with a first end of the fifth transmission line 315', and a second end of the first transmission line 311 'forms an input port connected with the feed 40'. A first end of the second transmission line 312 ' is connected to a second end of the fifth transmission line 315 ', the second end of the second transmission line 312 ' forming an output port connected to the antenna unit 20. A first end of the third transmission line 313 ' is connected to a first end of the seventh transmission line 317 ', and a second end of the third transmission line 313 ' forms a first connection port connected to a second end of the first decoupling transmission line 33. A first end of the fourth transmission line 314 ' is connected to a second end of the seventh transmission line 317 ', and a second end of the fourth transmission line 314 ' forms a second connection port connected to a second end of the second decoupling transmission line 34. Feed 40 and feed 40' may be the same feed.

The third and fourth transmission lines 313 'and 314' may be designed to have a short length, for example, the length of the third and fourth transmission lines 313 'and 314' may be only connected to the first and second decoupling transmission lines 33 and 34, and may not have a redundant length. This can reduce the influence on the length design of the first and second decoupling transmission lines 33, 34.

The characteristic impedance of fifth transmission line 315 'and seventh transmission line 317' may be designed to be Z₁The characteristic impedance of the sixth transmission line 316 'and the eighth transmission line 318' can be designed to be Z₂. In addition, the lengths of the fifth transmission line 315 ', the sixth transmission line 316', the seventh transmission line 317 ', and the eighth transmission line 318' may be set to (1/4) λ.

As further shown in connection with fig. 3, a first decoupling transmission line 33 and a second decoupling transmission line 34 are both connected between the first decoupling network 31 and the second decoupling network 31'. In particular, a first end of the first decoupling transmission line 33 is connected to a first connection port of the first decoupling network 31, i.e. to a second end of the third transmission line 313; the second end of the first decoupling transmission line 33 is connected to the first connection port of the second decoupling network 31 ', i.e. to the second end of the third transmission line 313'. Similarly, a first end of the second decoupling transmission line 34 is connected to a second connection port of the first decoupling network 31, i.e. to a second end of the fourth transmission line 314; a second end of the second decoupling transmission line 34 is connected to a second connection port of the second decoupling network 31 ', i.e. to a second end of the fourth transmission line 314'.

In fig. 3 to 5, the characteristic impedance of the first transmission line 311, the second transmission line 312, the third transmission line 313, the fourth transmission line 314, the first transmission line 311 ', the second transmission line 312', the third transmission line 313 ', the fourth transmission line 314', the first decoupling transmission line 33, and the second decoupling transmission line 34 may be designed as Z₀. In addition, the length of the first decoupling transmission line 33 can be set to d₃The length of the second decoupled transmission line 34 can be set to d₄。

It is pointed out here that the terms "first", "second" and "third" in the present application are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implying any number of indicated technical features. Thus, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of the feature.

The first and second decoupling transmission lines 33, 34 are used to transmit signals to cancel the mutual coupling between the two antenna elements 10, 20. Therein, the degree of coupling D1 between the two antenna elements 10, 20 can be determined by the scattering parameters (i.e. S-parameters) of the first and second decoupling networks 31, 31' and the lengths D of the first and second decoupling transmission lines 33, 34₃And d₄Are defined. For example, if the degree of coupling D1 between the two antenna elements 10, 20 is required to reach a predetermined degree of coupling, the S-parameter of the four-port network and the lengths D of the first and second decoupling transmission lines 33, 34 can be adjusted₃，d₄Is configured such that the degree of coupling D1 between the antenna elements 10, 20 satisfies a preset degree of coupling. It is pointed out here thatThe degree of coupling D1 between the antenna elements 10, 20 is inversely proportional to the degree of isolation between the two antenna elements 10, 20; that is, the higher the isolation between the two antenna elements 10, 20, the lower the degree of coupling D1 between the two antenna elements 10, 20.

It is readily apparent that when the first and second decoupling networks 31, 31' adopt the same structure, their S parameters are also the same. Thus, with the first and second decoupling networks 31, 31' being identical, the degree of coupling D1 between the two antenna elements 10, 20 and the S-parameter of the first decoupling network 31 and the length D of the first and second decoupling transmission lines 33, 34₃，d₄The relationship therebetween can be obtained in the following manner.

Matrix S of S-parameters of the first decoupling network 31₀Comprises the following steps:

wherein S is₁₂、S₁₃、S₃₁Are three of the S-parameters of the first decoupling network 31, which are, in particular, mutual coupling coefficients, which may be referred to as coupling coefficients, when the first decoupling network 31 is a four-port network.

At a reference plane iii, which can be selected by mathematical derivation, a first connection port and a second connection port of the first decoupling network 31 are each connected with a length d₃And d₄So that the matrix S of S-parameters of the first decoupling network 31 can be derived from the S-parameter calculation in equation (1):

wherein e is a natural constant, j is a symbol representing an imaginary number, k is a wave number, and S in the formula (1)₃₁Is equal to S in formula (2)₁₃。

Before the first decoupling network 31 and the second decoupling network 31' are not connected, an eight-port network is formed, and the relation of S parameters is as follows:

in the formula (3), a 1-a'₄Is an incident voltage wave amplitude, b 1-b'₄Is the reflected voltage wave amplitude.

Wherein:

writing the matrix in equation (3) as a block matrix form:

wherein S is₁₁、S₂₂、S₂₁Is one of three S parameters of a four-port network, and S₁₁Is the reflection coefficient, S₂₁Is the mutual coupling coefficient.

Written in the form of a system of equations:

equation (4) can be abbreviated from equation (6):

[a₂]＝[Γ]·[b₂] (7)

by substituting formula (7) for formula (6):

from the second expression in the formula (8):

[b₂]＝{E-[S₂₂][Γ]}^-1[S₂₁][a₁] (9)

in the formula (9), E represents an identity matrix.

The formula (9) is substituted for the formula (8) to obtain:

[b₁]＝[S₁₁][a₁]+[S₁₂][Γ]{E-[S₂₂][Γ]}^-1[S₂₁][a₁] (10)

from equation (10), it can be seen that a new matrix S of S parameters of the four-port network (1, 2, 1', 2 ') is formed between the first and second decoupling networks 31, 31 ' after connection by the first and second decoupling transmission lines 33, 34_Four-portComprises the following steps:

S_Four-port＝[S₁₁]+[S₁₂][Γ]{E-[S₂₂][Γ]}^-1[S₂₁] (11)

it is pointed out that the four ports of the new four-port network here are the four ports (a) that are connected to form an integral external unit after the first decoupling network 31 and the second decoupling network 31' are connected₁,b₁)、(a₂,b₂)、(a’₁,b’₁) And (a'₂,b’₂)。

Substituting the block matrixes planned by the formulas (3) and (5) into the formula (11) to obtain a new matrix S of S parameters of the new four-port network_Four-portComprises the following steps:

through digital operation, a matrix S of S parameters of the novel four-port network can be obtained_Four-portComprises the following steps:

the port order of the new four-port network is adjusted to 1 → 1'→ 2 → 2', and equation (13) becomes:

rewrite equation (14) into the form of a composition block matrix:

setting the matrix S of the S parameters of the binary antenna formed by the two antenna elements 10 and 20_arrayComprises the following steps:

(iii) in formula (16), S'₁₂Is the magnitude of the initial isolation, i.e., the strength of the isolation when no decoupling network is connected between two adjacent antenna elements 10 and 20; s'₁₁、S’₂₁And S'₂₂Respectively, when no decoupling network is connected between two adjacent antenna units 10 and 20₁,b₁) Reflection coefficient, isolation and output port (a)₂,b₂) The reflection coefficient of (2).

After the first and second decoupling networks 31 and 31' are connected together by the first and second decoupling transmission lines 33 and 34, a new four-port network is formed and then connected to the two antenna units 10 and 20, thereby forming a two-port network. The matrix [ S ] of S parameters for the two-port network is:

[S]＝[S₁₁]+[S₁₂][S_array]{E-[S₂₂][S_array]}^-1[S₂₁] (17)

it is noted that the two-port of the two-port network is the only two ports (a) connected to the feed source that remain after the new four-port network is connected to the antenna elements 10 and 20₁,b₁) And (a'₁,b’₁)。

By substituting the block matrices defined by equations (14) and (15) into equation (17), we can obtain:

from equation (18), the length d of the first and second decoupling transmission lines 33 and 34 is designed₃And d₄And the S-parameters of the four-port network, the degree of coupling D1 between the antenna elements can be precisely defined. That is, when the required coupling degree is preset, the above formula can be expressed as:

thus, the lengths d of the first and second decoupling transmission lines 33, 34 can be set₃And d₄And the S-parameter of the four-port network is configured such that the degree of coupling D1 between the antenna elements 10, 20 satisfies a preset degree of coupling.

For example, when the decoupling network is required to completely cancel the mutual coupling between the two antenna units 10 and 20, and the predetermined coupling degree is 0, then:

further, in the case of making the preset coupling degree 0, S may be set to₁'₂S-parameter representation with four port network:

let the coupling coefficient S of a four-port network (e.g., the aforementioned coupler)₁₃When D is equal to

Substituting the formula to obtain:

let k (d)₃+d₄)＝2π，

Wherein phi s₁₂Parameter S representing a four-port network₁₂Phase of (phi s)₁₃Parameter S representing a four-port network₁₃The phase of (c).

Further, the coupling degree D of the coupler can be calculated as follows:

and, the lengths d of the first and second decoupling transmission lines 33 and 34₃And d₄Respectively as follows:

wherein phi is₂₁For the phase of the pre-decoupling isolation pi corresponds to a value of pi, e.g. 3.14, S₁'₂Is the magnitude of the isolation before decoupling.

From this, it can be seen that S'₁₂Calculating the coupling degree D of the required directional coupler; can also be based on phi₂₁The lengths d of the first and second decoupling transmission lines 33, 34 are calculated₃And d₄. Wherein the length d of the first decoupled transmission line 33₃And the length d of said second decoupled transmission line 34₄The sum is an integer multiple of the wavelength.

In addition, under the condition that the preset coupling degree is 0, the required directional coupler can also meet the following structural parameters:

wherein, the first transmission line 311 and the second transmission line312. Characteristic impedances Z of the third 313, fourth 314, first 33 and second 34 decoupling transmission lines₀Usually predetermined, for example, set to 50 Ω; h may be an impedance transformation factor. Therefore, based on the degree of coupling D of the directional coupler calculated by equation (22), and further based on equations (24) and (25), the characteristic impedance of each branch of the directional coupler shown in fig. 4 can be determined, that is: characteristic impedance Z of fifth transmission line 315 and seventh transmission line 317₁And the characteristic impedance Z of the sixth transmission line 316 and the eighth transmission line 318₂. Further, the line width of the transmission line corresponding to the characteristic impedance can be calculated to manufacture the directional coupler. Based on the method, the isolation of the multi-antenna system can be improved.

In some embodiments, the characteristic impedance of the transmission line can be made satisfactory by configuring the line width of the transmission line. For example, the characteristic impedances Z of the first transmission line 311, the second transmission line 312, the third transmission line 313, the fourth transmission line 314, the first decoupled transmission line 33, and the second decoupled transmission line 34 are obtained in accordance with the above-described relational expressions₀Then, the line widths of these transmission lines may be configured so that their characteristic impedances satisfy the above-described characteristic impedance Z₀. For example, after determining the required thickness of the first transmission line 311, the second transmission line 312, the third transmission line 313, the fourth transmission line 314, the first decoupling transmission line 33 and the second decoupling transmission line 34, the relative dielectric constant of the PCB board, and the thickness of the dielectric layer, the relationship between the characteristic impedance and the line width and the required characteristic impedance Z are determined₀The line widths of the transmission lines can be calculated. Therefore, the line widths of the first transmission line 311, the second transmission line 312, the third transmission line 313, the fourth transmission line 314, the first decoupling transmission line 33, and the second decoupling transmission line 34 are configured according to the calculation result, thereby obtaining the characteristic impedance Z having the above-described characteristic impedance₀A plurality of transmission lines.

Similarly, the line widths of the fifth transmission line 315 and the seventh transmission line 317 may be configured such that they satisfy the above-described required characteristic impedance Z₁. The line widths of the sixth transmission line 316 and the eighth transmission line 318 can be determined according to the relationship between the characteristic impedance and the line width and the desired characteristicsImpedance Z₂To calculate. Therefore, the line widths of the fifth and seventh transmission lines 315, 317 and the sixth and eighth transmission lines 316, 318 are configured according to the calculation result, thereby obtaining the characteristic impedance Z having the above-described characteristic impedance₁And Z₂A plurality of transmission lines.

It will be appreciated that the four-port network described above may also be other forms of directional coupler, such as coupled line directional coupler, miniaturized directional coupler, broadband directional coupler.

In combination with the decoupling structure, the present application further provides a decoupling method for an antenna device, and fig. 6 is a schematic flow chart of the decoupling method for the antenna device according to the embodiment of the present application.

As shown in fig. 6, the decoupling method may mainly include the following operations S101-S102.

Operation S101: providing an antenna arrangement, the antenna arrangement comprising: the antenna comprises a first antenna unit and a second antenna unit which are adjacently arranged; a first decoupling network having an input port, an output port, a first connection port, and a second connection port; the output port is connected with the first antenna unit, and the input port is used for connecting a first feed source; a second decoupling network having an input port, an output port, a first connection port, and a second connection port; an output port of the second decoupling network is connected with the second antenna unit, and an input port of the second decoupling network is used for connecting a second feed source; a first decoupling transmission line connecting a first connection port of the first decoupling network with a first connection port of the second decoupling network; and a second decoupling transmission line connecting a second connection port of the first decoupling network with a second connection port of the second decoupling network.

As shown in fig. 2 to fig. 5, the description related to the antenna apparatus in the present application can be applied to the operation S101, and is not repeated herein.

Operation S102: the degree of coupling between the first and second antenna elements is defined in accordance with a first length of the first decoupling transmission line, a second length of the second decoupling transmission line, and scattering parameters of the first and second decoupling networks.

As shown in fig. 2 to 5, the description related to the first and second decoupling networks 31 and 31' and the first and second decoupling transmission lines 33 and 34 in the present application can be applied to the operation S102, and will not be described again.

In an embodiment, the decoupling method may further include the operations of: the first antenna element and the second antenna element are arranged to have the same radiation characteristics.

In an embodiment, the decoupling method may further include the operations of: the first and second decoupling networks are each designed as directional couplers.

In an embodiment, the decoupling method may further include the operations of: the first and second decoupling networks are arranged to have the same scattering parameters.

In an embodiment, the decoupling method may further include the operations of: defining a degree of coupling between said first antenna element and said second antenna element as D1, defining a first length of said first decoupled transmission line as D₃Defining a second length of said second decoupled transmission line as d₄And defining a scattering parameter of said first decoupling network as S₁₂And S₁₃The following relationship is satisfied between these parameters:

where e is a natural constant, j is an expression symbol of an imaginary number, and k is a wave number.

In an embodiment, the decoupling method may further include the operations of: determining a coupling degree of the first decoupling network according to a strength of an isolation degree when the first decoupling network and the second decoupling network are not connected between the first antenna unit and the second antenna unit.

In an embodiment, the decoupling method may further include the operations of: statorDefining the coupling degree of the first decoupling network as D, and defining the strength of isolation degree between the first antenna unit and the second antenna unit when the first decoupling network and the second decoupling network are not connected as S'₁₂These parameters satisfy the relationship defined by the above equation (22).

In an embodiment, the decoupling method may further include the operations of: the first decoupling network comprises a fifth transmission line, a sixth transmission line, a seventh transmission line and an eighth transmission line which are sequentially connected end to end, and the characteristic impedance of the fifth transmission line and the characteristic impedance of the seventh transmission line are designed to be Z₁A characteristic impedance of the sixth transmission line and the eighth transmission line is designed to be Z₂The characteristic impedance of the first and second decoupling transmission lines is designed to be Z₀(ii) a Wherein the degree of coupling D and Z of the first decoupling network₀、Z₁And Z₂Satisfies the relationship defined by the above-mentioned equations (24) and (25).

In an embodiment, the decoupling method may further include the operations of: the lengths of the fifth, sixth, seventh and eighth transmission lines are all set to (1/4) λ, where λ is the wavelength.

In an embodiment, the decoupling method may further include the operations of: according to characteristic impedance Z₀、Z₁And Z₂Calculating line widths of the fifth transmission line, the sixth transmission line, the seventh transmission line, the eighth transmission line, the first decoupling transmission line, and the second decoupling transmission line.

In an embodiment, the decoupling method may further include the operations of: the sum of the first length of the first decoupling transmission line and the second length of the second decoupling transmission line is an integer multiple of the wavelength.

In an embodiment, the decoupling method may further include the operations of: determining a first length of the first decoupling transmission line and a second length of the second decoupling transmission line according to a phase of an isolation when the first and second decoupling networks are not connected between the first and second antenna elements.

In an embodiment, the decoupling method may further include the operations of: defining a first length of said first decoupled transmission line as d₃Defining a second length of said second decoupled transmission line as d₄Defining a phase of isolation between the first antenna element and the second antenna element when the first decoupling network and the second decoupling network are not connected to each other as phi₂₁These parameters satisfy the relationship defined by the above equation (23).

It is readily apparent that the same matters described in the decoupling principle section of the present application are applicable to the decoupling method and will not be described in detail here.

In some embodiments, the electronic device of the present application may be a cell phone 100a as shown in fig. 7, the cell phone 100a including, but not limited to, the following structures: a housing 41 and a display screen assembly 50 coupled to the housing 41. Wherein, an accommodating space is formed between the housing 41 and the display screen assembly 50. Other electronic components of the mobile phone, such as a main board, a battery, and the antenna device 60, are disposed in the accommodating space.

Specifically, the housing 41 may be made of plastic, glass, ceramic, fiber composite, metal (e.g., stainless steel, aluminum, etc.), or other suitable material. The housing 41 shown in fig. 7 is generally rectangular with rounded corners. Of course, the housing 41 may have other shapes, such as circular, oblong, elliptical, and the like.

The display panel assembly 50 includes a display panel cover 51 and a display module 52. The display module 52 is attached to the inner surface of the display cover 51. The housing 41 is connected to a display cover 51 of the display assembly 50. The display screen cover plate 51 may be made of glass; the display module 52 may be an OLED flexible display structure, and may specifically include a substrate, a display Panel (Panel), an auxiliary material layer, and the like, and a polarizing film may be further interposed between the display module 52 and the display Panel cover plate 51, and a detailed stacked structure of the display module 52 is not limited herein.

The antenna device 60 may be completely housed inside the housing 41, or may be embedded in the housing 41, and a part of the antenna device 60 may be exposed on the outer surface of the housing 41.

The antenna arrangement 60 may comprise a plurality of antenna elements, for example the antenna module 60 shown in fig. 8 to 12 is a quaternary linear array, i.e. having four linearly arranged antenna elements 10a, 20a, 10b and 20 b. Specifically, referring to fig. 12, the antenna device 60 includes a first substrate 61, a second substrate 62, a third substrate 63, and a radio frequency chip 64, which are sequentially stacked, and a plurality of antenna units (only two antenna units 10a and 20a are shown in fig. 12) formed on the first substrate 61, a plurality of metal layers 661-668 formed on the first substrate 61 and the third substrate 63 (where the metal layer 665 is a ground layer 665), a feed line passing through the third substrate 63 and the second substrate 62, and a first decoupling network 31 and a second decoupling network 31' formed on the third substrate 63, and a first decoupling transmission line 33 and a second decoupling transmission line 34 connected therebetween. The feeding lines correspond to the antenna units 10a and 20a one to one, and are respectively used for connecting the corresponding antenna units 10a and 20a with the radio frequency chip 64. The first and second decoupling networks 31, 31' and the first and second decoupling transmission lines 33, 34 connected therebetween are used to connect the corresponding feed lines of the adjacent antenna elements 10a, 20a together to cancel the coupling between the antenna elements 10a, 20 a. The first and second decoupling transmission lines 33, 34 may both be in the same planar layer, for example disposed within a third substrate 63; in addition, the first and second decoupling transmission lines 33 and 34 may be arranged in a meander shape to satisfy a length design. It is understood that the antenna device 60 may also include other signal transmission lines.

The antenna elements 10a, 20a are used for transceiving radio frequency signals. As shown in fig. 12, the two antenna elements 10a, 20a are disposed at a distance from each other. The antenna units 10a, 20a are double-layered patch antennas, and include surface radiation pieces 11a, 21a and inner radiation pieces 12a, 22a that are isolated from each other and correspond to each other one to one.

The first substrate 61 includes a first outer surface 611 and a first inner surface 612 disposed opposite to each other. The surface radiation sheets 11a and 21a are disposed on the first outer surface 611, and the inner radiation sheets 12a and 22a are disposed on the first inner surface 612. The inner radiation sheets 12a and 22a are isolated from the surface radiation sheets 11a and 21a by the first substrate 61, so that the surface radiation sheets 11a and 21a and the inner radiation sheets 12a and 22a are spaced by a certain distance, thereby meeting the performance requirement of the antenna frequency band. The surface radiation pieces 11a and 21a and the inner radiation pieces 12a and 22a are at least partially overlapped in a vertical projection on the first substrate 61.

The first substrate 61 may be made of a thermosetting resin such as an epoxy resin, a thermoplastic resin such as a polyimide resin, an insulating material (e.g., prepreg, ABF (Ajinomoto fabric-up Film), a photo dielectric (PID), etc.) including a reinforcing material such as a glass fiber (or glass cloth ) and/or an inorganic filler, and a thermosetting resin and a thermoplastic resin. However, the material of the first substrate 61 is not limited thereto. That is, a glass plate or a ceramic plate may also be used as the material of the first substrate 61. Alternatively, a Liquid Crystal Polymer (LCP) having a low dielectric loss may also be used as the material of the first substrate 61 to reduce signal loss.

In some embodiments, the first substrate 61 may be a prepreg, and as shown in fig. 12, the first substrate 61 includes three layers of prepregs stacked. In the three prepregs of the first substrate 61, metal layers 662 and 663 are respectively provided between adjacent prepregs. The first substrate 61 is further provided with a metal layer 661 on the first outer surface, wherein the metal layer 661 and the surface radiation pieces 11a and 21a are located on the same layer and are insulated from each other. The first inner surface 612 of the first substrate 61 is provided with a metal layer 664, and the metal layer 664 and the inner radiation sheets 12a and 22a are located at the same layer and insulated from each other. The metal layers 661, 662, 663 and 664 may be made of conductive materials such as metallic copper, aluminum, silver, tin, gold, nickel, lead, titanium or their alloys. In this embodiment, the metal layers 661, 662, 663 and 664 are all copper layers.

The metal layer 661 is provided to reduce a difference between a copper plating ratio of the first outer surface 611 of the first substrate 61 and a copper plating ratio of the surface of the other prepreg of the first substrate 61, and the difference between the copper plating ratios can reduce the generation of bubbles during the manufacturing process of the first substrate 61, thereby improving the manufacturing yield of the first substrate 61. Similarly, the metal layer 664 is also disposed to reduce the difference between the copper spreading rate of the first inner surface 612 of the first substrate 61 and the copper spreading rate of the surfaces of the other prepregs of the first substrate 61, so as to reduce the generation of bubbles during the manufacturing process of the first substrate 61, thereby improving the manufacturing yield of the first substrate 61.

The first substrate 61 is also provided with ground vias 613 through the first inner surface 612 and the first outer surface 611 to connect the different metal layers 661,662, 663 and 664 to each other and further to the ground layer 665. Specifically, the conductive material may completely fill the ground via 613, or the conductive material may form a conductive layer along the wall of the ground via 613. The conductive material may be copper, aluminum, silver, tin, gold, nickel, lead, titanium, or an alloy thereof. The ground via 613 may have a cylindrical shape, an hourglass shape, a conical shape, or the like.

The second substrate 62 includes a first side surface 621 and a second side surface 622, wherein the first side surface 621 is overlapped on the first inner surface 612 of the first substrate 61. The second substrate 62 may be a core layer of a PCB board and is made of polyimide, polyethylene terephthalate, polyethylene naphthalate, or the like. The second substrate 62 is provided with a ground via 623 and a feeder via 624 penetrating the first and second side surfaces 621 and 622.

The ground layer 665 is interposed between the second substrate 62 and the third substrate 63. The ground layer 665 is provided with a feed line via 665 a.

The third substrate 63 includes a second outer surface 631 and a second inner surface 632 oppositely disposed. Second inner surface 632 of third substrate 63 is stacked on second side surface 622 of second substrate 62, and ground layer 665 is sandwiched between second side surface 622 and second inner surface 632.

The third substrate 63 may be formed of the same material as the first substrate 61. In some embodiments, the third substrate 63 may be a prepreg, as shown in fig. 12, and the third substrate 63 includes three layers of prepregs. In the three layers of prepregs of the third substrate 63, metal layers 666 and 667 are provided between adjacent prepregs as a feeding network and a control line wiring layer, respectively. A metal layer 668 is disposed on the second outer surface 631 of the third substrate 63, and the metal layer 668 is soldered to the rf chip 64. The metal layers 666, 667, and 668 can be made of conductive material such as copper, aluminum, silver, tin, gold, nickel, lead, titanium, or their alloys. In this embodiment, metal layers 666, 667, and 668 are all copper layers.

The third substrate 63 has a wiring via hole. The routing vias include ground vias 633 to connect the different metal layers 666, 667, and 668 to each other and further to a ground layer 665. The routing vias also include a feed line via 634 through which a feed line passes, a signal via 635 through which a control line passes, and the like. Similar to the ground via 613 on the first substrate 61, the wiring via on the third substrate 63 may be completely filled with a conductive material, or a conductive layer may be formed on the wall of the via. The various wiring vias may be cylindrical, hourglass-shaped, or pyramid-shaped in shape.

A feed line has one end connected to the rf chip 64 and the other end penetrating through the feed line via 634 of the third substrate 63 and coupled to the first decoupling network 31. Another feed line has one end connected to the first decoupling network 31 and the other end connected to the inner radiation pieces 12a, 22a through the feed line via 665a of the ground layer 665 and the feed line via 624 of the second substrate 62 to transmit signals between the antenna elements 10a, 20a and the radio frequency chip 64. In particular, the feeder comprises a first feeder 31a and a second feeder 32a connected by a decoupling network. The first feed line 31a is connected to the rf chip 64, and the second feed line 32a is connected to the inner radiation fins 12a and 22 a. The feed lines are insulated from the metal layers, such as metal layers 666, 667, 668, and the ground layer of this embodiment. Note here that the first feed line 31a in fig. 12 may connect the first transmission line 311 in fig. 3, and the second feed line 32a may connect the second transmission line 312 in fig. 3.

In addition, other signal transmission lines, such as a control line 68 and a power line 69, are provided on the third substrate 63. As shown in fig. 12, the power supply line 69 is provided on the second outer surface 631 of the third substrate 63 and is soldered on the rf chip 64. The control line 68 is disposed between the prepreg of the third substrate 63 close to the rf chip 64 and the prepreg adjacent to the prepreg, and passes through the signal via 635 on the prepreg layer to be connected to the rf chip 64.

The third substrate 63 is furthermore used to carry a first and a second decoupling network 31, 31' and a first and a second decoupling transmission line 33, 34 connected between them. As shown in fig. 12, the first and second decoupling networks 31 and 31' and the first and second decoupling transmission lines 33 and 34 connected therebetween are connected between the feeder lines corresponding to the adjacent antennas 10a, 20 a. The first decoupling network 31 is connected at the connection of the first feeder 31a and the second feeder 32a corresponding to one antenna unit 10 a; in particular, the first transmission line 311 (see fig. 3) of the first decoupling network 31 is connected to the first feeder 31a, and the second transmission line 312 of the first decoupling network 31 is connected to the second feeder 32 a. Similarly, the second decoupling network 31' is connected at the connection of the first feeder 31a and the second feeder 32a corresponding to the adjacent antenna unit 20 a; that is, the first transmission line 311 '(see fig. 5) of the second decoupling network 31' is connected to the first feeder 31a corresponding to the antenna element 20a, and the second transmission line 312 'of the second decoupling network 31' is connected to the second feeder 32a corresponding to the antenna element 20 a.

Since the first and second decoupling networks 31, 31 ' are provided between two adjacent antenna units of the antenna device, and the first and second decoupling transmission lines 33, 34 are connected between the first and second decoupling networks 31, 31 ', after a signal emitted from the radio chip 64 passes through the first feed line 31a, a portion thereof is transmitted to the inner-layer radiating patch 12a of the antenna unit through the first and second decoupling networks 31, 32a, and another portion thereof is transmitted to the second decoupling network 31 ' to reach the adjacent antenna unit 20a through the first and second decoupling transmission lines 31, 33, 34, thereby canceling the coupling between the two antenna units 10a, 20a to some extent.

The degree of coupling between the two antenna elements 10a, 20a can be defined by the S-parameters of the first and second decoupling networks 31, 31' and the lengths of the first and second decoupling transmission lines 33, 34. Specifically, as in the above-described embodiments of the array antenna, the lengths d of the first and second decoupling transmission lines 33 and 34 of the antenna device 60 of the present embodiment₃And d₄The S-parameter of the first decoupling network 31, and the predetermined degree of coupling satisfy the following relationship:

in some embodiments, the length d of the first and second decoupling transmission lines 33, 34 may be varied₃And d₄And the S-parameter of the first decoupling network 31 is configured to null the degree of coupling D1 between the two antenna elements 10a, 20 a.

Further, in some embodiments, in the case of setting the degree of coupling D1 between the two antenna elements 10a and 20a to zero, the degree of coupling D of the required directional coupler is calculated according to the initial isolation S12' between the two antenna elements 10a and 20a, specifically referring to the aforementioned formula (22).

As shown in fig. 11, which is a partial schematic view of the antenna arrangement of fig. 10, the arrangement of the first and second decoupling networks 31, 31' and the first and second decoupling transmission lines 33, 34 connected between them is mainly shown. In this embodiment, the first and second decoupling transmission lines 33, 34 are in different meandering arrangements, wherein the length d of the first decoupling transmission line 33₃Comprising a plurality of bends, i.e. d₃L1 × 2+ L2 × 2+ L3. Length d of second decoupled transmission line 34₄Comprising a plurality of bends, i.e. d₄＝L4*2+L5*2+L6。

Further, d₃And d₄The result of the addition may be approximately equal to twice the wavelength, i.e., 2 x λ 6.45mm 12.9 mm.

Since the second decoupling network 31 'may be identical to the first decoupling network 31, the arrangement of the transmission lines of the second decoupling network 31' may be identical to the meandering arrangement of the transmission lines in the first decoupling network 31.

In some embodiments, the phase phi can also be based on the pre-decoupling isolation₂₁The lengths d of the first and second decoupling transmission lines 33, 34 are calculated₃And d₄See, in particular, equation (23) above.

In some embodiments, based on the calculated degree of coupling D of the directional coupler, the characteristic impedance of each branch of the directional coupler can be determined, that is: first transmission line 311, second transmission lineCharacteristic impedances Z of the transmission line 312, the third transmission line 313, the fourth transmission line 314, the first decoupling transmission line 33 and the second decoupling transmission line 34₀Characteristic impedances Z of fifth transmission line 315 and seventh transmission line 317₁And the characteristic impedance Z of the sixth transmission line 316 and the eighth transmission line 318₂See, in particular, the aforementioned formulas (24) and (25). Further, the line width of the transmission line corresponding to the characteristic impedance can be calculated to manufacture the directional coupler.

As described in the above embodiments of the antenna array, the characteristic impedance of the transmission line can be made satisfactory by configuring the line width of the transmission line. For example, the line widths of the first transmission line 311, the second transmission line 312, the third transmission line 313, the fourth transmission line 314, the first decoupling transmission line 33, and the second decoupling transmission line 34 are configured such that their characteristic impedances satisfy the above-described characteristic impedance Z₀. The line widths of the fifth transmission line 315 and the seventh transmission line 317 are configured such that their characteristic impedances satisfy the above-described characteristic impedance Z₁. The line widths of the sixth transmission line 316 and the eighth transmission line 318 are configured such that their characteristic impedances satisfy the above-described characteristic impedance Z₂。

Accordingly, the first and second decoupling networks 31 and 31' and the first and second decoupling transmission lines 33 and 34 connected therebetween can be formed on the layer on which the metal layer 666 is formed in a length satisfying the above-described desired length. It is understood that when the linear distance between the feed lines corresponding to the adjacent antenna units 10a and 20a is small, the first decoupling transmission line 33 and the second decoupling transmission line 34 may form a zigzag pattern to meet the requirement of length (as shown in fig. 10 and 11). In other embodiments, the first decoupled transmission line 33 may also be in a curved pattern, as long as the length requirement is met.

The first and second decoupling networks 31, 31' and the first and second decoupling transmission lines 33, 34 connected between them are located at different layers from the skin and inner radiating patches 11a, 21a, 12a, 22 a. As shown in fig. 12, the first and second decoupling networks 31, 31' and the first and second decoupling transmission lines 33, 34 connected therebetween are disposed below the antenna elements 10a, 20a, for example, within a third substrate 63. The first and second decoupling networks 31 and 31' and the first and second decoupling transmission lines 33 and 34 connected therebetween shown in fig. 12 are located at the same layer as the metal layer 666, i.e., between the prepreg of the third substrate 63 closest to the ground layer 665 and its adjacent prepreg. It will be appreciated that in other embodiments the first and second decoupling networks 31, 31' and the first and second decoupling transmission lines 33, 34 connected between them may also be layered with the metal layers 667 or 668.

The above description has been made with respect to the two antenna elements 10a and 20a, the first and second decoupling networks 31 and 31', and the first and second decoupling transmission lines 33 and 34. However, it is easily understood that, as shown in fig. 10, the decoupling structure of the present application may also be provided similarly for the antenna units 20a and 10b and the antenna units 10b and 20 b. For example, a third and a fourth decoupling network 35, 35 'and a third and a fourth decoupling transmission line 33', 34 'connected between the third and the fourth decoupling network 35, 35' can be provided for the antenna units 20a and 10 b; the third decoupling network 35 may be identical or similar to the first decoupling network 31 described above, and the fourth decoupling network 35 'may be identical or similar to the second decoupling network 31' described above; the third decoupling transmission line 33 'may be the same as or similar to the first decoupling transmission line 33 described above, and the fourth decoupling transmission line 34' may be the same as or similar to the second decoupling transmission line 34 described above. In addition, the second and third decoupling networks 31 ', 35 may share part of the transmission lines, for example the first, second and fifth transmission lines 311 ', 312 ', 315 ' (see fig. 5) of the second decoupling network 31 '.

When more than three antenna elements are used as shown in fig. 10, these decoupling networks and decoupling transmission lines may also be distributed in different layers. For example, the first and second decoupling networks 31 and 31 ' and the first and second decoupling transmission lines 33 and 34 connected therebetween may be distributed at the layer where the metal layer 666 shown in fig. 12 is located, and the third and fourth decoupling networks 35 and 35 ' and the third and fourth decoupling transmission lines 33 ' and 34 ' connected between the third and fourth decoupling networks 35 and 35 ' may be distributed at the layer where the metal layer 667 shown in fig. 12 is located.

Referring to fig. 13, a schematic diagram of an antenna apparatus according to another embodiment of the present application is shown. In the antenna device 60 of this embodiment, for example, the top end portion of the middle frame 42 of the mobile phone may be divided into two sections by the slit 44, and the two sections may be used as the first antenna 10a and the second antenna 20a, respectively. A circuit board 43 may be provided in the middle frame 42, and the first and second decoupling networks 31 and 31' and the first and second decoupling transmission lines 33 and 34 (see fig. 3) described above in the present application may be disposed on the circuit board 43. The feed 40 and feed 40' may be connected to the circuit board 43, which circuit board 43 is in turn connected to the first antenna 10a and the second antenna 20 a. The slot 44 may be generally non-centrally located, such as near the left or right side of the center frame 42.

In the example of the present application where the decoupling design is performed with a four-element linear array as shown in fig. 8 to 10, the center operating frequency of the four-element linear array is 28 GHz. It is noted that according to the 3GPP TS 38.101 protocol, frequencies between 24.25GHz and 52.6GHz are commonly referred to as millimeter waves (mm Wave); therefore, the decoupling structure provided by the application can be a millimeter wave array antenna decoupling structure. Fig. 14 shows a comparison of the coupling coefficients of the antenna elements before and after connecting the decoupling network. As can be seen from fig. 14, at the center operating frequency of 28 GHz: influenced by the coupling effect, the coupling coefficient between the units before decoupling is-13.5 dB; after decoupling, the coupling coefficient of the antenna is reduced by 25dB compared with that before decoupling, and the coupling effect among units is obviously inhibited.

Fig. 15 shows a comparison of the reflection coefficients of the antenna elements before and after connection of the decoupling network. As can be seen from the figure, under the influence of the coupling effect, the resonant frequency of the unit in the array before decoupling is shifted from 28GHz to 29.5GHz, the shift amount reaches 1.5GHz, and the shift degree is serious; after the technology of the application is utilized for decoupling, the resonant frequency of the array unit is 28.2GHz and is consistent with that of an isolated unit, and the matching characteristic of the antenna is obviously improved.

Fig. 16 and 17 show comparative curves of the radiation performance of the antenna arrangement before and after connection of the decoupling network when the beam is scanned to 0 °. As can be seen, the gain before decoupling is 11.40 dB; due to the influence of the coupling effect, the decoupled gain is 11.15dB, and is reduced by 0.25 dB.

Fig. 18 and 19 show comparative curves of the radiation performance of the antenna arrangement before and after connection of the decoupling network, with the beam scanned to 45 °. As can be seen, the gain before decoupling is 8.70 dB; due to the coupling effect, the decoupled gain is 10.21dB, which is improved by 1.51 dB.

Fig. 20 and 21 show comparative curves of the radiation performance of the antenna arrangement before and after connection of the decoupling network, with the beam scanned to 50 °. As can be seen, the gain before decoupling is 7.47 dB; the gain after decoupling is 9.48dB, improved by 2.01dB, influenced by the coupling effect.

Fig. 22 shows a graph of the radiation performance of the antenna arrangement when the beam is scanned to 55 deg. after connection of the decoupling network. It is noted here that it is not possible to sweep to 55 ° before decoupling. As can be seen from fig. 19, due to the coupling effect, it can sweep to 55 ° after decoupling and the gain is 8.55dB, 1.08dB higher than the gain of 7.47dB for 50 ° pointing before decoupling. Therefore, after the decoupling network is adopted, the isolation characteristic is improved, and the mutual coupling coefficient can be reduced to be lower than-30 dB; the scanning range is increased, and the scanning angle can be expanded to 55 degrees; the array gain is improved by 2dB compared with the scanning to 50 degrees.

In summary, the antenna device of the present application introduces the concept of decoupling network under the antenna unit, without changing the structure of the array antenna unit, only the length d of the first decoupling transmission line 33 and the second decoupling transmission line 34₃And d₄And the S parameter of the four-port network is configured, so that the coupling degree D1 between the antenna units 10 and 20 can be adjusted, the mutual coupling between the antenna units can be reduced, the scanning angle is expanded, and the scanning gain is improved. In addition, the coupling degree D of the directional coupler can be calculated according to the amplitude of the isolation degree before decoupling, the characteristic impedance of each branch of the directional coupler is determined according to a formula, and the line width of a transmission line corresponding to the characteristic impedance can be further calculated, so that the directional coupler can be manufactured. Based on the method, the isolation of the multi-antenna system can be improved.

The above description is only an example of the present application and is not intended to limit the scope of the present application, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the specification and the drawings, or which are directly or indirectly applied to other related technical fields, are intended to be included within the scope of the present application.

Claims (20)

1. An antenna device, comprising:

a plurality of antenna elements;

a plurality of decoupling networks in one-to-one correspondence with the plurality of antenna elements; each decoupling network is provided with an input port, an output port, a first connecting port and a second connecting port, a feeder line is connected between the output port and the corresponding antenna unit, and the input port is used for being connected with the radio frequency chip;

a first decoupling transmission line connected between first connection ports of adjacent decoupling networks; and

a second decoupling transmission line connected between second connection ports of adjacent decoupling networks.

2. The antenna device of claim 1, wherein:

the antenna device comprises a first substrate, a second substrate and a third substrate which are sequentially stacked;

the antenna unit is formed on the first substrate;

a plurality of the feed lines are located within the third substrate and the second substrate; and is

The plurality of decoupling networks, the first decoupling transmission line, and the second decoupling transmission line are disposed on the third substrate.

3. The antenna device of claim 2, wherein:

the third substrate is a multilayer structure, and the first and second decoupling transmission lines are disposed on a layer of the third substrate.

4. The antenna device of claim 3, wherein:

at least one of the first and second decoupling transmission lines forms a meandering or curved pattern.

5. The antenna device of claim 2, wherein:

every antenna element all includes mutual isolation and corresponds top layer radiation piece and the inlayer radiation piece that sets up, top layer radiation piece sets up first base plate is kept away from the surface of second base plate, the inlayer radiation piece sets up first base plate is close to the surface of second base plate.

6. The antenna device according to any of claims 1-5, characterized in that:

the plurality of antenna units comprise a first antenna unit, a second antenna unit and a third antenna unit, and the first antenna unit, the second antenna unit and the third antenna unit are arranged in a linear array;

the plurality of decoupling networks includes a first decoupling network, a second decoupling network, a third decoupling network, and a fourth decoupling network;

wherein the first decoupling transmission line is connected between first connection ports of the first and second adjacent decoupling networks; the second decoupling transmission line is connected between the first decoupling network and a second connection port of the second decoupling network;

the input port of the first decoupling network is used for connecting the radio frequency chip, and the output port of the first decoupling network is connected with the first antenna unit;

the input port of the second decoupling network is used for connecting the radio frequency chip, and the output port of the second decoupling network is connected with the second antenna unit;

an input port of the third decoupling network is used for connecting the radio frequency chip, and an output port of the third decoupling network is connected with the second antenna unit;

an input port of the fourth decoupling network is used for connecting the radio frequency chip, and an output port of the fourth decoupling network is connected with the third antenna unit;

a third decoupling transmission line connects a first connection port of the third decoupling network with a first connection port of the fourth decoupling network; and

a fourth decoupling transmission line connects the second connection port of the third decoupling network with the second connection port of the fourth decoupling network.

7. The antenna device of claim 6, wherein:

the second decoupling network and the third decoupling network share a portion of the transmission line.

8. The antenna device of claim 1, wherein:

the coupling degree between two adjacent antenna units is determined according to the first length of the first decoupling transmission line, the second length of the second decoupling transmission line and the scattering parameter of the decoupling network.

9. The antenna device of claim 1, wherein:

the decoupling networks are all directional couplers.

10. The antenna device of claim 1, wherein:

the decoupling networks have the same scattering parameters.

11. The antenna device of claim 10, wherein:

defining a first length of said first decoupled transmission line as d₃Defining a second length of said second decoupled transmission line as d₄Defining a scattering parameter of said first decoupling network as S₁₂And S₁₃And according toThe following relationship determines the degree of coupling D1 between the first and second antenna elements:

where e is a natural constant, j is an expression symbol of an imaginary number, and k is a wave number.

12. The antenna device of claim 10, wherein:

the coupling degree of the decoupling network is determined according to the strength of the isolation degree when the decoupling network is not connected between two adjacent antenna units.

13. The antenna device of claim 12, wherein:

d is defined as the coupling degree of the decoupling network, and S 'is defined as the strength of isolation degree when the decoupling network is not connected between two adjacent antenna units'₁₂The following relationship is satisfied between these parameters:

14. the antenna device of claim 13, wherein:

the decoupling network comprises a fifth transmission line, a sixth transmission line, a seventh transmission line and an eighth transmission line which are sequentially connected end to end, and the characteristic impedance of the fifth transmission line and the seventh transmission line is Z₁A characteristic impedance of the sixth transmission line and the eighth transmission line is Z₂Said first and second decoupled transmission lines having a characteristic impedance Z₀(ii) a Wherein the coupling degree D and Z of the decoupling network₀、Z₁And Z₂The following relationship is satisfied:

where h is the impedance transformation factor.

15. The antenna device of claim 14, wherein:

the fifth, sixth, seventh and eighth transmission lines are all set to (1/4) λ in length, where λ is the wavelength; and/or

The line widths of the fifth transmission line, the sixth transmission line, the seventh transmission line, the eighth transmission line, the first decoupling transmission line and the second decoupling transmission line are according to a characteristic impedance Z₀、Z₁And Z₂A determination is made.

16. The antenna device of claim 10, wherein:

the sum of the first length of the first decoupling transmission line and the second length of the second decoupling transmission line is an integer multiple of the wavelength.

17. The antenna device of claim 10, wherein:

the first length of the first decoupling transmission line and the second length of the second decoupling transmission line are determined according to a phase of an isolation when the decoupling network is not connected between adjacent two of the antenna units.

18. The antenna device of claim 17, wherein:

defining a first length of said first decoupled transmission line as d₃Defining a second length of said second decoupled transmission line as d₄Defining no connection between two adjacent antenna elementsThe phase of the isolation in the decoupling network is phi₂₁The following relationship is satisfied between these parameters:

wherein pi corresponds to a value of pi, and λ is the wavelength.

19. An electronic device, comprising:

a housing;

the display screen assembly is connected with the shell and forms an accommodating space with the shell;

the radio frequency chip is arranged in the accommodating space; and

an antenna device at least partially disposed in the accommodating space, the antenna device comprising:

a plurality of spaced apart antenna elements;

a plurality of decoupling networks in one-to-one correspondence with the plurality of antenna units, wherein each decoupling network has an input port, an output port, a first connection port, and a second connection port; a first feeder is connected between the output port and the corresponding antenna unit, and a second feeder is connected between the input port and the radio frequency chip;

a first decoupling transmission line connected between first connection ports of adjacent decoupling networks; and

a second decoupling transmission line connected between second connection ports of adjacent decoupling networks.

20. The electronic device according to claim 19, wherein the antenna device includes a first substrate, a second substrate, and a third substrate which are sequentially stacked; the plurality of antenna units are arranged on the first substrate; the first and second decoupling transmission lines are disposed within the third substrate; the radio frequency chip is arranged on one side of the third substrate far away from the second substrate.

Images