Patent Description:
To bring a more comfortable visual experience to users, the bezel-less screen industry design (industry design, ID) has become a design trend of portable electronic devices such as mobile phones. The bezel-less screen means a large screen-to-body ratio (usually over <NUM>%). The bezel width of the bezel-less screen is greatly reduced, and internal components of the phone, such as the front-facing camera, receiver, fingerprint reader, and antenna, need to be rearranged. Especially for the antenna design, the clearance area is reduced and the antenna space is further compressed. However, the size, bandwidth, and efficiency of the antenna are correlated and affect each other. If the antenna size (space) is reduced, the efficiency-bandwidth product (efficiency-bandwidth product) of the antenna is definitely reduced. Therefore, the bezel-less screen ID poses great challenges to the antenna design of mobile phones.

An antenna design form commonly used in an existing electronic device such as a mobile phone may be a planar inverted F (planar inverted F) antenna, an inverted F (inverted F) antenna, a monopole (monopole) antenna, a T-shaped antenna, a loop (loop) antenna, or the like. For these antenna designs, the antenna length needs to be at least one quarter to one half of a low-frequency wavelength. This has a high requirement on the antenna space.

How to design an antenna in limited space and meet antenna performance requirements is a research direction in the industry.

The document <CIT> shows an antenna configuration with couplers for wireless communication.

The document <CIT> shows an antenna system. Especially, antennas in frames for display panels are shown.

The document <CIT> shows a multi-feed antenna with independent tuning capacity.

The document <CIT> U shows an antenna system for handheld devices, especially a <NUM> MIMO antenna system. The document <NPL>, is a scientific paper dealing with integrated smartphone antennas. The document <CIT> shows a near field antenna architecture for mobile communication devices with a single-piece metal housing.

dependent claims show further advantages developments.

According to the embodiments of the present invention, an antenna apparatus and an electronic device are provided, can effectively excite a ground plane to generate radiation, and are applicable to a bezel-less electronic device whose antenna space is sharply reduced, because a radiation capability of the ground plane is not affected by a size of a clearance between a display screen and the ground plane.

According to a first aspect, this application provides an antenna apparatus. As shown in <FIG>, the antenna apparatus may include a ground plane <NUM> and an exciting element <NUM> of an electronic device.

The ground plane <NUM> includes a first side (for example, a lateral side <NUM>-<NUM>) and a second side (for example, a lateral side <NUM>-<NUM>) that are opposite to each other, and a third side (for example, a bottom side <NUM>-<NUM>) and a fourth side (for example, a top side <NUM>-<NUM>) that are opposite to each other.

The exciting element <NUM> may have a first branch <NUM>-<NUM> and two second branches (<NUM>-<NUM> and <NUM>-<NUM>). The second branch <NUM>-<NUM> and the second branch <NUM>-<NUM> may be respectively connected to two ends of the first branch <NUM>-<NUM>. An end of the second branch <NUM>-<NUM> that is away from the first branch <NUM>-<NUM> is connected to the ground plane <NUM>, and an end of the second branch <NUM>-<NUM> that is away from the first branch <NUM>-<NUM> is connected to the ground plane <NUM>. The second branch <NUM>-<NUM> and the second branch <NUM>-<NUM> may be used to set the first branch <NUM>-<NUM> on the ground plane <NUM>, and a gap is formed between the first branch <NUM>-<NUM> and the ground plane <NUM>.

The exciting element <NUM> may be set on the ground plane <NUM> in proximity to the first side of the ground plane <NUM>. Herein, the proximity may mean that a distance between the exciting element <NUM> and the first side is less than a specific distance, for example, <NUM>. The specific distance is not limited to <NUM>, and may alternatively be a value such as <NUM>, <NUM>, or <NUM>. In this case, a distance L1 from the exciting element <NUM> to the first side is less than a distance L2 from the exciting element <NUM> to the second side.

A first end of the exciting element is an end close to the third side of the ground plane, and a second end of the exciting element is an end close to the fourth side of the ground plane. The distance p1 from the first end of the exciting element to the third side of the ground plane is equal to the distance p2 from a second end of the exciting element to the fourth side of the ground plane.

A feeding port <NUM> is disposed on the exciting element <NUM>, and a signal source is located in the feeding port <NUM>. A first slot may be disposed on the first branch <NUM>-<NUM> of the exciting element <NUM>, and a first capacitor may be connected in series between two parts of the first branch on both sides of the first slot. The first capacitor may be configured to implement a codirectional current distributed on the exciting element <NUM>.

It can be seen that, in the antenna apparatus provided in the first aspect, an exciting element is set above a ground plane of an electronic device (for example, a mobile phone), and the exciting element is fed to effectively excite the ground plane to generate radiation. In this way, because a radiation capability of the ground plane is not affected by a size of a clearance between a display screen and the ground plane, the antenna solution provided in this application is applicable to a bezel-less electronic device whose antenna space is sharply reduced. In addition, the ground plane serves as one of main radiation apertures of an electronic device (for example, a mobile phone), and exciting the ground plane to generate radiation can significantly improve antenna performance. With reference to the first aspect, in some embodiments, the exciting element <NUM> may be parallel to the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane <NUM>, or a smaller included angle may be presented between the exciting element <NUM> and the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane <NUM>. In other words, the exciting element <NUM> and the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane <NUM> may be nearly parallel. The smaller included angle may be less than a first angle, such as <NUM>°. The first angle is not limited to <NUM>°, and may alternatively be an angle such as <NUM>° or <NUM>°. In this case, an included angle α between the exciting element <NUM> and the first side is less than an included angle β between the exciting element <NUM> and the third side. The exciting element <NUM> may be parallel to the first side of the ground plane <NUM>. In other words, the included angle α is equal to <NUM>°. In this case, the exciting element <NUM> may excite the ground plane <NUM> to generate a stronger current at the first side, and the exciting element <NUM> is more likely to excite the ground plane <NUM> to generate resonance. With reference to the first aspect, in some embodiments, the first slot may be disposed in the middle of the first branch <NUM>-<NUM>, so that the codirectional current on the exciting element <NUM> is stronger, and the ground plane <NUM> is more likely to be excited to generate radiation. The first capacitor is a distributed capacitor (for example, a distributed capacitor formed by disposing a gap on the exciting element <NUM>).

With reference to the first aspect, a feeding form at the feeding port <NUM> includes the following manner:
In an implementation, as shown in <FIG>, the feeding port <NUM> is specifically disposed on the second branch <NUM>-<NUM> or the second branch <NUM>-<NUM>, and may be specifically implemented by disposing a gap <NUM> on the second branch. An inductor L connected in series in <FIG> may be configured to implement impedance matching. A matching network integrated at the feeding port will be described in the following content.

With reference to the first aspect, in some embodiments, the first branch <NUM>-<NUM> may be a horizontal branch parallel to the ground plane <NUM>. Optionally, the second branch <NUM>-<NUM> and the second branch <NUM>-<NUM> may be vertical branches perpendicular to the ground plane <NUM>, and are used to suspend the first branch <NUM>-<NUM> on the ground plane <NUM>.

With reference to the first aspect, in some embodiments, the exciting element <NUM> may be parallel to the first side. In this case, the included angle α=<NUM> and the included angle β=<NUM>°. In this case, the exciting element <NUM> is more likely to excite the ground plane <NUM> to generate radiation.

With reference to the first aspect, in some embodiments, the exciting element <NUM> may be set on the first side of the ground plane. In this case, L1 is equal to <NUM>. In this case, the exciting element <NUM> is more likely to excite the ground plane <NUM> to generate radiation. In other words, a closer proximity of the exciting element <NUM> to the first side indicates that the ground plane <NUM> is more likely to be excited to generate radiation.

With reference to the first aspect, the distance p1 and the distance p2 are equal, and both are equal to (Lg-Le)/<NUM>. In this case, the exciting element <NUM> may be set in the middle of the ground plane in proximity to the first side, and the exciting element <NUM> is more likely to excite the ground plane <NUM> to generate resonance.

With reference to the first aspect, in some embodiments, the matching network integrated at the feeding port may include a capacitor C and an inductor L, the capacitor C is connected in series to the feeding port, and the inductor L is connected in parallel to the feeding port. The capacitor C may be referred to as a second capacitor, and the inductor L may be referred to as a first inductor.

With reference to the first aspect, in some embodiments, the antenna apparatus provided in this application may further implement a dual-band, a wide-band, or a multi-band, and may be implemented by using the matching network or adding more magnetic rings. Details are described below.

To implement dual-band matching, the matching network may be: An LC parallel circuit (consisting of L2 and C2 connected in parallel) is connected in series after a capacitor C1 is connected in series, and finally an inductor L2 is connected in parallel. In other words, the matching network integrated at the feeding port may include: The capacitor C1, the LC parallel circuit, and the inductor L2 are connected in series, the capacitor C1 and the LC parallel circuit are connected in series to the feeding port once, and the inductor L2 is connected in parallel to the feeding port. The capacitor C1 may be referred to as a third capacitor, the inductor L2 may be referred to as a second inductor, the capacitor C2 in the LC parallel circuit may be referred to as a fourth capacitor, and the inductor L2 in the LC parallel circuit may be referred to as a third inductor. Optionally, the dual-band may be a low-band (for example, at <NUM>) and a GPS L1 band (at <NUM>). A configuration for the dual-band matching network may be as follows: C1=<NUM> pF, L1=<NUM> nH, C2=<NUM> pF, and L2=<NUM> nH.

To implement a dual-band or a wide-band, a parasitic element (which may also be referred to as a parasitic magnetic ring) may be set on the ground plane <NUM>. In other words, the antenna apparatus provided in this application may further include a parasitic element. On the ground plane <NUM>, like the exciting element <NUM>, the parasitic element may be set in proximity to the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane. Herein, the proximity may mean that a distance between the parasitic element and the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane is less than a specific distance (for example, <NUM>). In this case, a distance L3 from the parasitic element to the first side of the ground plane is less than a distance L4 from the parasitic element to the second side of the ground plane.

While the exciting element <NUM> excites the ground plane <NUM> to generate radiation, the ground plane <NUM> couples the parasitic element to generate radiation, thereby implementing dual-band radiation.

In some embodiments, the parasitic element may have a same structure as the exciting element <NUM>. The parasitic element may have a third branch and two fourth branches. The third branch is similar to the first branch <NUM>-<NUM> in the exciting element <NUM>, and the fourth branches are similar to the second branches <NUM>-<NUM> and <NUM>-<NUM> in the exciting element <NUM>. Similar to the structure of the exciting element <NUM>, the two fourth branches in the parasitic element may be respectively connected to two ends of the third branch. An end of the fourth branch that is away from the first branch is connected to the ground plane <NUM>. The two fourth branches may be used to set the third branch on the ground plane <NUM>, so that a gap is formed between the third branch and the ground plane <NUM>. Like the exciting element <NUM>, a capacitor may be connected in series on the parasitic element. The capacitor may be referred to as a fifth capacitor. To connect the fifth capacitor in series, a gap may be disposed on the third branch, and the fifth capacitor may be connected in series between two parts of the third branch on both sides of the gap. The gap may be referred to as a second slot.

The parasitic element is not limited to the parasitic magnetic ring having the same structure as the exciting element <NUM>. To implement a multi-band or a wide-band, the parasitic element may alternatively be another antenna, such as a support antenna or a floating antenna. The support antenna may include an IFA antenna, an ILA antenna, and the like.

To describe the technical solutions in the embodiments of this application more clearly, the following illustrates the accompanying drawings in the embodiments of this application.

The technical solutions provided in this application are applicable to an electronic device that uses one or more of the following communications technologies: a Bluetooth (bluetooth, BT) communications technology, a global positioning system (global positioning system, GPS) communications technology, a wireless fidelity (wireless fidelity, Wi-Fi) communications technology, a global system for mobile communications (global system for mobile communications, GSM) communications technology, a wideband code division multiple access (wideband code division multiple access, WCDMA) communications technology, a long term evolution (long term evolution, LTE) communications technology, a <NUM> communications technology, a SUB-<NUM> communications technology, and other future communications technologies. In this application, the electronic device may be a mobile phone, a tablet computer, a personal digital assistant (personal digital assistant, PDA), or the like.

<FIG> shows an example of an internal environment of an electronic device on which an antenna design solution provided in this application is based. As shown in <FIG>, the electronic device <NUM> may include a display screen <NUM>, a printed circuit board PCB <NUM>, a ground plane <NUM>, a bezel <NUM>, and a back cover <NUM>. The display screen <NUM>, the printed circuit board PCB <NUM>, the ground plane <NUM>, and the back cover <NUM> may be respectively disposed at different layers. These layers may be parallel to each other. A plane on which the layers are located may be referred to as an X-Z plane, and a direction perpendicular to the X-Z plane is a Y direction. In other words, the display screen <NUM>, the printed circuit board PCB <NUM>, the ground plane <NUM>, and the back cover <NUM> may be layered and distributed in the Y direction.

The printed circuit board PCB <NUM> may be an FR-<NUM> dielectric board, or may be a Rogers (Rogers) dielectric board, or may be a Rogers and FR-<NUM> hybrid dielectric board, or the like. Herein, FR-<NUM> is a code name for the grade of a flame-resistant material, and the Rogers dielectric board is a high-frequency board.

The back cover <NUM> is a back cover made of a non-conductive material, for example, a non-metal back cover such as a glass back cover or a plastic back cover.

The ground plane <NUM> is grounded, and may be disposed between the printed circuit board PCB <NUM> and the back cover <NUM>. The ground plane <NUM> may also be referred to as a PCB ground plane. Specifically, the ground plane <NUM> may be a layer of metal etched on a surface of the PCB <NUM>. This layer of metal may be connected to a metal middle frame (not shown) by using a series of metal elastomers, and is integrated with the metal middle frame. The ground plane <NUM> may be configured to ground an electronic element carried on the printed circuit board PCB <NUM>. Specifically, the electronic element carried on the printed circuit board PCB <NUM> may be grounded by connecting the electronic element to the ground plane <NUM>, to prevent a user from being electrocuted or device damage.

The bezel <NUM> may be disposed around edges of the ground plane <NUM>, and may cover the printed circuit board PCB <NUM> and the ground plane <NUM> between the back cover <NUM> and the display screen <NUM> from lateral sides, to achieve dust-proof and waterproof purposes. The bezel <NUM> may be a metal bezel or a non-metal bezel. The bezel <NUM> may include a frame (which may be referred to as a top frame) <NUM>-<NUM> on a top of the electronic device <NUM>, a frame (which may be referred to as a bottom frame) <NUM>-<NUM> at a bottom of the electronic device <NUM>, and frames (which may be referred to as side frames) <NUM>-<NUM> and <NUM>-<NUM> on lateral sides of the electronic device <NUM>. A front-facing camera (not shown), an earpiece (not shown), an optical proximity sensor (not shown), an ambient optical sensor (not shown), and the like may be disposed on the top of the electronic device <NUM>. A USB charging interface (not shown), a microphone (not shown), and the like may be disposed at the bottom of the electronic device <NUM>. A volume adjustment button (not shown) and a power button (not shown) may be disposed at the lateral sides of the electronic device <NUM>.

<FIG> shows only each part included in the electronic device <NUM> schematically, and an actual shape, an actual size, and an actual structure of each part are not limited by <FIG>. The display screen <NUM> of the electronic device <NUM> may be a large-sized display screen, and a screen-to-body ratio may reach more than <NUM>%.

Based on the internal environment of the electronic device shown in <FIG>, this application provides a ground plane radiation antenna solution based on magnetic ring feed. In the antenna solution provided in this application, an exciting element is set above the ground plane <NUM>, and the exciting element is fed, to effectively excite the ground plane <NUM> to generate radiation. In this way, because a radiation capability of the ground plane <NUM> is not affected by a size of a clearance between the display screen <NUM> and the ground plane <NUM>, the antenna solution provided in this application is applicable to a bezel-less ID whose antenna space is sharply reduced. In addition, the ground plane <NUM> is one of main radiation apertures of the electronic device <NUM>, and exciting the ground plane <NUM> to generate radiation can significantly improve antenna performance.

<FIG> show an antenna apparatus according to this application. <FIG> is a schematic diagram of an overall model of the antenna apparatus, <FIG> is a plane view of an antenna structure in an X-Z plane, and <FIG> is a detailed view of a ring exciting element in the antenna structure. As shown in <FIG>, the antenna apparatus may include a ground plane (ground plane) <NUM> and an exciting element (exciting element) <NUM>.

The ground plane <NUM> may have a lateral side <NUM>-<NUM> and a lateral side <NUM>-<NUM> that are opposite to each other, and a top side <NUM>-<NUM> and a bottom side <NUM>-<NUM> that are opposite to each other. The sides of the ground plane <NUM> are respectively close to the frames of the bezel <NUM>. Specifically, the lateral side <NUM>-<NUM> is close to the side frame <NUM>-<NUM>, the top side <NUM>-<NUM> is close to the top frame <NUM>-<NUM>, the lateral side <NUM>-<NUM> is close to the side frame <NUM>-<NUM>, and the bottom side <NUM>-<NUM> is close to the bottom frame <NUM>-<NUM>. Optionally, the ground plane <NUM> may be rectangular, the lateral side <NUM>-<NUM> and the lateral side <NUM>-<NUM> may be two opposite long sides, and the top side <NUM>-<NUM> and the bottom side <NUM>-<NUM> may be two opposite short sides.

The exciting element <NUM> may be set on the ground plane <NUM> in proximity to a side of the ground plane <NUM>. This side may be referred to as a first side of the ground plane <NUM>. Herein, the proximity may mean that a distance between the exciting element <NUM> and the first side of the ground plane <NUM> is less than a specific distance, such as <NUM>. A smaller distance between the exciting element <NUM> and the first side of the ground plane <NUM> indicates that the ground plane <NUM> is more likely to be excited to generate radiation. This will be analyzed in the following content, and details are not described herein. Optionally, the first side of the ground plane <NUM> may be a long side of the ground plane <NUM>.

The exciting element <NUM> may be parallel to the first side of the ground plane <NUM>, or a smaller included angle may be presented between the exciting element <NUM> and the first side of the ground plane <NUM>. In other words, the exciting element <NUM> and the first side may be parallel or nearly parallel. The smaller included angle may be less than a first angle, such as <NUM>°. The first angle is not limited to <NUM>°, and may alternatively be an angle such as <NUM>° or <NUM>°.

The exciting element <NUM> may have a first branch <NUM>-<NUM> and two second branches (<NUM>-<NUM>, <NUM>-<NUM>). The second branch <NUM>-<NUM> and the second branch <NUM>-<NUM> may be respectively connected to two ends of the first branch <NUM>-<NUM>. The two ends of the first branch <NUM>-<NUM> may include one end <NUM>-<NUM> close to the top side <NUM>-<NUM> and one end <NUM>-<NUM> close to the bottom side <NUM>-<NUM>. An end of the second branch <NUM>-<NUM> that is away from the first branch <NUM>-<NUM> is connected to the ground plane <NUM>, and an end of the second branch <NUM>-<NUM> that is away from the first branch <NUM>-<NUM> is connected to the ground plane <NUM>. The second branch <NUM>-<NUM> and the second branch <NUM>-<NUM> may be used to set the first branch <NUM>-<NUM> on the ground plane <NUM>, and a gap is formed between the first branch <NUM>-<NUM> and the ground plane <NUM>. In other words, the first branch <NUM>-<NUM> is not in contact with the ground plane <NUM>. Optionally, the first branch <NUM>-<NUM> may be a horizontal branch parallel to the ground plane <NUM>. Optionally, the second branch <NUM>-<NUM> and the second branch <NUM>-<NUM> may be vertical branches perpendicular to the ground plane <NUM>, and are used to suspend the first branch <NUM>-<NUM> on the ground plane <NUM>.

<FIG> and <FIG> further show examples of a size of the ground plane <NUM>, a size of the exciting element <NUM>, and a position of the exciting element <NUM> on the ground plane <NUM>. Specifically, a length Lg of the ground plane <NUM> may be <NUM>, and a width Wg of the ground plane <NUM> may be <NUM>. Herein, the width Wg of the ground plane <NUM> is a length of a short side (for example, <NUM>-<NUM> or <NUM>-<NUM> in <FIG>), and the length Lg of the ground plane <NUM> is a length of a long side (for example, <NUM>-<NUM> or <NUM>-<NUM> in <FIG>). A length Le of the exciting element <NUM> may be <NUM>, and a height h of the exciting element <NUM> may be <NUM>. Herein, the length Le of the exciting element <NUM> is a length of the first branch <NUM>-<NUM>, and the height h of the exciting element <NUM> is a length of the second branch. A distance w between the exciting element <NUM> and the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane <NUM> may be <NUM>, and a distance p between the end <NUM>-<NUM> of the exciting element <NUM> and the bottom side <NUM>-<NUM> of the ground plane <NUM> may be <NUM>. Lg, Wg, Le, h, w, and p are not limited to the drawings, and may alternatively be other values, and impact of their values on antenna performance is described in detail in the following content.

As shown in <FIG>, a feeding port <NUM> may be disposed on the exciting element <NUM>, and a signal source is located in the feeding port <NUM>. In an implementation, as shown in <FIG>, the feeding port <NUM> may be specifically disposed on the first branch <NUM>-<NUM>, and may be specifically implemented by disposing a gap <NUM> on the first branch <NUM>-<NUM>. The gap <NUM> divides the first branch <NUM>-<NUM> into two parts (<NUM>-<NUM>-A and <NUM>-<NUM>-B), and the signal source may be connected in series between the first branch <NUM>-<NUM>-A and the first branch <NUM>-<NUM>-B. In another implementation, as shown in <FIG>, the feeding port <NUM> may be specifically disposed on the second branch <NUM>-<NUM> or the second branch <NUM>-<NUM>, and may be specifically implemented by disposing a gap <NUM> on the second branch. An inductor L connected in series in <FIG> may be configured to implement impedance matching. A matching network integrated at the feeding port will be described in the following content.

As shown in <FIG>, a capacitor C1 may be further connected in series on the exciting element <NUM>, and the capacitor C1 may be referred to as a first capacitor. The first capacitor may be configured to implement a codirectional current distributed on the exciting element <NUM>. To connect the first capacitor in series, as shown in <FIG>, a gap <NUM> may be disposed on the first branch <NUM>-<NUM>. The gap <NUM> may divide the first branch <NUM>-<NUM> into two parts (<NUM>-<NUM>-A and <NUM>-<NUM>-B), and the first capacitor may be connected in series between the first branch <NUM>-<NUM>-A and the first branch <NUM>-<NUM>-B. The gap <NUM> in which the first capacitor is located may be referred to as a first slot. Optionally, the first slot may be disposed in the middle of the first branch <NUM>-<NUM>, so that the codirectional current on the exciting element <NUM> is stronger, and the ground plane <NUM> is more likely to be excited to generate radiation. The first capacitor may be a lumped capacitor or a distributed capacitor (for example, a distributed capacitor formed by disposing a gap on the exciting element <NUM>).

In an example not forming part of the claimed invention, but nonetheless useful for the understanding of the invention, as shown in <FIG>, only one gap, for example, the gap <NUM>, may be disposed on the exciting element <NUM>. In the gap <NUM>, the first capacitor and the signal source may form a series circuit, and then the series circuit may be integrally connected in series between the two parts of the first branch (that is, the first branch <NUM>-<NUM>-A and the first branch <NUM>-<NUM>-B) on both sides of the gap <NUM>. In other words, the gap in which the first capacitor is located and the gap in which the feeding port is located may be a same gap, and this is not limited thereto. The gap in which the first capacitor is located and the gap in which the feeding port is located may alternatively be two different gaps.

A matching network may be integrated at the feeding port <NUM>. The matching network may be used to adjust (by adjusting an antenna transmit coefficient, an impedance, and the like) a band range covered by the antenna apparatus provided in this application. The matching network may include various structures that can implement impedance matching, such as an impedance conversion line or a lumped element network. A lumped element may include an element such as a capacitor or an inductor. Specifically, an input impedance of the antenna may be adjusted by changing a line width of the impedance conversion line and changing an electrical characteristic parameter (for example, a capacitance value and an inductance value) of a component in the lumped element network, to implement impedance matching.

The following describes a matching principle of the exciting element <NUM>. When no matching element is used (namely, there is no matching network), the input impedance in an expected band (for example, <NUM> to <NUM>) is mainly in an inductive area. In this case, S11 simulation of the antenna apparatus may be shown by curve a1 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b1 and c1 in <FIG>. When only a capacitor C (for example, C=<NUM> pF) is connected in series to the feeding port, the input impedance in an expected band (for example, <NUM> to <NUM>) is manifested as being in a capacitive area in a low band (for example, <NUM> to <NUM>), and in an inductive area in a high band (for example, <NUM> to <NUM>). In this case, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b2 and c2 in <FIG>. As shown in <FIG>, when the matching network at the feeding port is first connected in series to a capacitor C (for example, C=<NUM> pF) and then connected to an inductor L (for example, L=<NUM> nH), S11 simulation of the antenna apparatus may be shown by curve a3 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b3 and c3 in <FIG>.

It can be seen that curve a1 has no resonance, curve a2 has one shallow resonance, and curve a3 has one deep resonance. In addition, antenna efficiency represented by curve b3 is clearly better than antenna efficiency represented by curves b1 and b2. In other words, good impedance matching may be performed on the exciting element <NUM> by first connecting the capacitor C in series to the feeding port and then connecting the inductor L in parallel, so that the exciting element <NUM> can effectively excite the ground plane <NUM> to generate radiation. In other words, the matching network integrated at the feeding port may include a capacitor C and an inductor L, the capacitor C is connected in series to the feeding port, and the inductor L is connected in parallel to the feeding port. The capacitor C may be referred to as a second capacitor, and the inductor L may be referred to as a first inductor.

The following uses a <NUM> operating band as an example to describe an operating principle of the antenna apparatus provided in this application. It is assumed that the matching network integrated at the feeding port is that a <NUM> pF capacitor is first connected in series, and then a <NUM> nH inductor is connected in parallel. Current distribution of the antenna apparatus provided in this application operating at <NUM> may be shown in <FIG>. A codirectional current <NUM> is distributed on the exciting element <NUM>, and the codirectional current <NUM> distributed on the ring-shaped exciting element <NUM> may be equivalent to a magnetic current. Therefore, the exciting element <NUM> may be referred to as a "magnetic ring". The codirectional current <NUM> may excite the ground plane <NUM> to generate a longitudinal current <NUM>, to excite the ground plane <NUM> to generate resonance, and excite the ground plane <NUM> to generate radiation. <FIG> are respectively a front view and an aerial view of a three-dimensional radiation pattern simulated by the antenna apparatus provided in this application operating at <NUM>. As shown in <FIG>, a shape of the three-dimensional radiation pattern is similar to that of a radiation pattern of a <NUM>/<NUM>-wavelength dipole. Because a current of the ground plane <NUM> is mainly concentrated on the lateral side <NUM>-<NUM> of the ground plane <NUM>, the three-dimensional radiation pattern is mainly inclined to one side.

It can be seen that, by setting the exciting element <NUM> above the ground plane <NUM>, feeding the exciting element <NUM>, and setting an appropriate matching network at the feeding port, the ground plane <NUM> can be effectively excited to generate radiation. In this way, the requirement on antenna space can be reduced, the antenna solution provided in this application is applicable to a bezel-less ID whose antenna space is sharply reduced, and antenna performance can be significantly improved.

The following describes application of the antenna design solution provided in this application to an actual overall system model.

For example, the distance p between the exciting element <NUM> shown in <FIG> and the bottom side <NUM>-<NUM> of the ground plane <NUM> is an important parameter of the exciting element <NUM> in the actual overall system model. It is assumed that Lg=<NUM>, Wg=<NUM>, Le=<NUM>, and h=<NUM>. Using a GPS L5 operating band as an example, <FIG> and <FIG> show S11 simulation and antenna efficiency of an antenna apparatus when p is two different values. When p=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a1 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b1 and c1 in <FIG>. When p=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b2 and c2 in <FIG>.

It can be seen that a resonance position and a resonance depth of S11 simulation are basically the same when p=<NUM> and p=<NUM>, and peak system efficiency is about -<NUM> dB. System efficiency when P=<NUM> is slightly higher than that when P=<NUM>. The reasons will be analyzed in the following content. In addition, an upper hemisphere proportion is about <NUM>% when p=<NUM> and <NUM>% when p=<NUM>. A higher upper hemisphere proportion indicates stronger radiation in a longitudinal direction of the antenna, namely, stronger radiation in the Z direction.

Apart from the distance p between the exciting element <NUM> and the bottom side <NUM>-<NUM> of the ground plane <NUM>, the size of the ground plane <NUM>, the size of the exciting element <NUM>, and the distance w between the exciting element <NUM> and the lateral side <NUM>-<NUM> of the ground plane <NUM> may also be important parameters of the antenna apparatus provided in this application in an actual overall system model. Values of these parameters affect antenna performance. The following describes impact of a parameter on antenna performance in detail by using a single variable as a principle (namely, a single parameter is changed and other parameters remain unchanged).

If the length Le of the exciting element <NUM> increases, the resonance of the antenna is at a lower band, and the resonance depth becomes deeper. If the length Le of the exciting element <NUM> decreases, the resonance of the antenna is at a higher band, and the resonance depth becomes lower.

For example, using a <NUM> operating band as an example, <FIG> and <FIG> show S11 simulation and antenna efficiency of an antenna apparatus when Le is several different values. When Le=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a1 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b1 and c1 in <FIG>. When Le = <NUM>, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b2 and c2 in <FIG>. When Le=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a3 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b3 and c3 in <FIG>.

Among the antenna performance at the different Les, when Le=<NUM>, the antenna apparatus has the lowest resonance frequency (closest to <NUM>), and the highest resonance depth (up to -<NUM> dB). When Le=<NUM>, the antenna apparatus has the highest resonance frequency (closest to <NUM>) and the lowest resonance depth (about -<NUM> dB). It can be seen that as the length Le becomes shorter from <NUM> to <NUM> and <NUM>, the resonance of the antenna moves towards a high frequency and the resonance depth becomes lower.

For a case in which the resonance becomes lower because the length Le of the exciting element <NUM> is reduced, the resonance depth may be increased by reducing the parallel inductor. For example, as shown in <FIG> and <FIG>, curve a4 represents S11 simulation of the antenna apparatus when Le=<NUM> and L=<NUM> nH, and curves b4 and c4 represent system efficiency and radiation efficiency of the antenna apparatus when Le=<NUM> and L=<NUM> nH. It can be seen that the parallel inductor L is reduced from L=<NUM> nH to L=<NUM> nH, so that the depth of the resonance can be increased from -<NUM> dB to -<NUM> dB.

If the height h of the exciting element <NUM> decreases, the resonance of the antenna moves towards a high frequency, and the resonance depth becomes lower.

For example, using a <NUM> operating band as an example, <FIG> and <FIG> show S11 simulation and antenna efficiency of an antenna apparatus when h is several different values. When h=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a1 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b1 and c1 in <FIG>. When h=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b2 and c2 in <FIG>. When h=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a3 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b3 and c3 in <FIG>.

Among the antenna performance at different hs, when h=<NUM>, the antenna apparatus has the lowest resonance frequency (about <NUM>), and the highest resonance depth (up to -<NUM> dB). When h=<NUM>, the antenna apparatus has the highest resonance frequency (close to <NUM>) and the lowest resonance depth (about -<NUM> dB). It can be seen that as the height h decreases from <NUM> to <NUM> and <NUM>, the resonance of the antenna moves towards a high frequency and the resonance depth becomes lower.

For a case in which the resonance moves towards a high frequency because the height h of the exciting element <NUM> is reduced, the resonance may return to a low frequency by increasing the length Le. For example, as shown in <FIG> and <FIG>, curve a4 represents S11 simulation of the antenna apparatus when h=<NUM> and Le=(<NUM>+<NUM>) mm, and curves b4 and c4 represent system efficiency and radiation efficiency of the antenna apparatus when h=<NUM> and Le=(<NUM>+<NUM>) mm. It can be seen that the length of the exciting element <NUM> is increased from <NUM> to (<NUM>+<NUM>) mm, so that the antenna resonance can return to the low frequency (<NUM>). In this case, the peak efficiency of the antenna is only reduced by about <NUM> dB, there is no significant deterioration, and the antenna bandwidth is also slightly reduced. The antenna performance is not very sensitive to the height of the exciting element <NUM>.

The position of the exciting element <NUM> may be embodied by parameters of two dimensions: a distance w between the exciting element <NUM> and the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane, and a distance p between the exciting element <NUM> and the third side (for example, the bottom side <NUM>-<NUM>) of the ground plane. The first side and the third side may be two connected sides of the ground plane <NUM>, and may be perpendicular to each other.

A smaller distance w indicates that the exciting element <NUM> is closer to the lateral side <NUM>-<NUM> of the ground plane <NUM>. When w=<NUM>, it indicates that the exciting element <NUM> is set at the lateral side <NUM>-<NUM>. A larger distance w indicates that the exciting element <NUM> is closer to the middle of the ground plane <NUM> in the Y direction.

Reducing the distance w may cause the resonance of the antenna to move towards the low frequency, and increase the resonance depth. Increasing the distance w can cause the resonance of the antenna to moves toward the high frequency, and reduce the resonance depth. This is because an intrinsic current of the ground plane <NUM> is mainly concentrated on the ground plane <NUM> due to the edge effect. When the exciting element <NUM> moves towards the middle of the ground plane <NUM> (that is, w becomes larger), the codirectional current on the exciting element <NUM> is difficult to couple to the intrinsic current of the ground plane <NUM>. Therefore, it is difficult to excite the ground plane <NUM> to generate radiation.

For example, using a <NUM> operating band as an example, <FIG> and <FIG> show S11 simulation and antenna efficiency of an antenna apparatus when w is several different values. In <FIG> and <FIG>, d=<NUM> (d represents a height of a metal bezel) indicates that no metal bezel is disposed at lateral sides of the ground plane <NUM>, namely, the bezel <NUM> is a non-metal bezel. When w=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a1 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b1 and c1 in <FIG>. When w=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b2 and c2 in <FIG>. When w=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a3 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b3 and c3 in <FIG>.

Among the antenna performance at different ws, when w=<NUM>, the antenna apparatus has the lowest resonance frequency (about <NUM>), and the lowest resonance depth (up to -<NUM> dB). When w=<NUM>, the antenna apparatus has the highest resonance frequency (close to <NUM>), and the lowest resonance depth (about -<NUM> dB). It can be seen that as the height w increases from <NUM> to <NUM> and <NUM>, the resonance of the antenna moves towards high frequency, and the resonance depth becomes lower, and the peak efficiency and bandwidth of the system also decrease significantly.

In addition, a metal bezel (d is not equal to <NUM>) is disposed at lateral sides of the ground plane <NUM>, so that the resonance of the antenna moves towards high frequency, and the resonance depth becomes lower. This is because the metal bezel may be equivalent to an epitaxy of the ground plane <NUM>, and the intrinsic current of the ground plane <NUM> is mainly concentrated on the metal bezel due to the edge effect. This is equivalent to outward expansion of the ground plane <NUM>. In this case, the system efficiency peak and bandwidth of the antenna also decrease.

For example, using a <NUM> operating band as an example, as shown in <FIG> and <FIG>, when d=<NUM> (d represents a height of a metal bezel) and w=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a3 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b3 and c3 in <FIG>. When d=<NUM> (d represents a height of the metal bezel) and w=<NUM>, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and system efficiency and radiation efficiency of the antenna apparatus may be shown by curves b2 and c2 in <FIG>. It can be seen that, when both ws are <NUM>, antenna performance when d=<NUM> is clearly weaker than antenna performance when d=<NUM>. The resonance moves towards high frequency, the resonance depth becomes lower, and the peak system efficiency and bandwidth clearly decrease.

A smaller distance p indicates that the exciting element <NUM> is closer to the bottom side <NUM>-<NUM> of the ground plane <NUM>. A larger distance p indicates that the exciting element <NUM> is farther away from the bottom side <NUM>-<NUM> of the ground plane <NUM> in the Z direction.

Assuming that the length Lg of the ground plane <NUM> is <NUM>, and the length of the exciting element <NUM> is <NUM>, when p=<NUM>, p=(Lg - Le)/<NUM>. This may indicate that the exciting element <NUM> is disposed in the middle of the ground plane <NUM> in the Z direction. Increasing p (for example, p=<NUM>+<NUM>) or decreasing p (for example, p=<NUM>-<NUM>) causes the exciting element <NUM> to deviate from the middle of the ground plane <NUM>. This may result in a lower resonance depth of the antenna, smaller peak efficiency of the system, and a smaller bandwidth. This is because the ground plane <NUM> has the strongest intrinsic current in the middle of the ground plane <NUM> in the Z direction, and the intrinsic current becomes weaker at positions away from the middle. When the exciting element <NUM> is away from the middle of the ground plane <NUM> in the Z direction, coupling between the codirectional current on the exciting element <NUM> and the intrinsic current of the ground plane <NUM> becomes weaker, and the ground plane <NUM> is unlikely to be excited to generate radiation, causing poor antenna performance.

For example, using a <NUM> operating band as an example, <FIG> and <FIG> show S11 simulation and antenna efficiency of an antenna apparatus when p is several different values. It can be seen that when p=<NUM>, the antenna has the highest resonance depth, and the largest peak system efficiency and bandwidth. When p=<NUM>, p=<NUM>, p=<NUM>, and p=<NUM>, the resonance depth of the antenna becomes lower, and the peak system efficiency and bandwidth become smaller.

In addition, a closer proximity of the exciting element <NUM> to the bottom side <NUM>-<NUM> of the ground plane <NUM> (namely, a smaller p) indicates a larger upper hemisphere proportion of the antenna radiation pattern, and stronger radiation in the longitudinal direction of the antenna, namely, stronger radiation in the Z direction. A longer distance between the exciting element <NUM> and the bottom side <NUM>-<NUM> of the ground plane <NUM> (that is, a larger p) indicates a smaller upper hemisphere proportion of the antenna radiation pattern, and weaker radiation in the longitudinal direction of the antenna, namely, weaker radiation in the Z direction.

For example, using a <NUM> operating band as an example, <FIG> is an antenna radiation pattern of an antenna apparatus when p is several different values. As shown in <FIG>, when p=<NUM>, the upper hemisphere proportion is <NUM>%; when p=<NUM>, the upper hemisphere proportion is <NUM>%; when p=<NUM>, the upper hemisphere proportion is <NUM>%; when p=<NUM>, the upper hemisphere proportion is <NUM>%; and when p=<NUM>, the upper hemisphere proportion is <NUM>%.

The size of the ground plane <NUM> may be embodied by parameters of two dimensions: a length Lg of the ground plane <NUM> and a width Wg of the ground plane <NUM>.

Assuming that Wg=<NUM>, as shown in <FIG> and <FIG>, when Lg is prolonged by <NUM> or shortened by <NUM> based on <NUM>, the resonance position of the antenna is basically unchanged because the width of the ground plane <NUM> is large and a characteristic impedance of the ground plane <NUM> is small. Resonance of the antenna apparatus provided in this application is more affected by the length Le of the exciting element <NUM> because a characteristic impedance of the exciting element <NUM> is larger.

As shown in <FIG> and <FIG>, when Wg is widened by <NUM> or narrowed by <NUM> based on <NUM>, the resonance position of the antenna is basically unchanged. However, when the ground plane <NUM> becomes narrower (that is, Wg decreases), the resonance of the antenna becomes deeper, and the system efficiency peak and bandwidth become larger. This is because a narrower ground plane <NUM> indicates that the intrinsic current of the ground plane <NUM> is more concentrated on the ground plane <NUM>. In this way, coupling between the ground plane <NUM> and the exciting element <NUM> set in proximity to the ground plane <NUM> is stronger, and the ground plane <NUM> is more likely to be excited to generate radiation.

Sizes of the exciting element <NUM> and the ground plane <NUM> may be determined based on sizes of an overall system model to which the antenna apparatus provided in this application is actually applied. To make the exciting element <NUM> effectively excite the ground plane <NUM> to generate radiation, a relative position relationship between the exciting element <NUM> and the ground plane <NUM> may be as follows:.

The foregoing content describes a design solution of an antenna operating at a single band. The single band may be a <NUM> low-frequency band, a GPS L5, a GPS L1, or the like. In addition to the single band, the antenna apparatus provided in this application may further implement a dual-band, a wide-band, or a multi-band, and may be implemented by using the matching network or adding more magnetic rings. Details are described below.

As shown in <FIG>, to implement dual-band matching, the matching network may be that an LC parallel circuit (consisting of L2 and C2) is connected in series after a capacitor C1 is connected in series, and finally an inductor L2 is connected in parallel. In other words, the matching network integrated at the feeding port may include: The capacitor C1, the LC parallel circuit, and the inductor L2 are connected in series, the capacitor C1 and the LC parallel circuit are connected in series to the feeding port once, and the inductor L2 is connected in parallel to the feeding port. The capacitor C1 may be referred to as a third capacitor, the inductor L2 may be referred to as a second inductor, the capacitor C2 in the LC parallel circuit may be referred to as a fourth capacitor, and the inductor L2 in the LC parallel circuit may be referred to as a third inductor. Optionally, the dual-band may be a low-band (for example, at <NUM>) and a GPS L1 band (at <NUM>). A configuration of the matching network for the dual-band may be as follows: C1=<NUM> pF, L1=<NUM> nH, and C2=<NUM> pF, L2=<NUM> nH. By setting the dual-band matching network at the feeding port, antenna performance of the antenna apparatus provided in this application may be shown in <FIG> shows S11 simulation of the antenna apparatus.

As shown in <FIG>, to implement a dual-band or a wide-band, a parasitic element (which may also be referred to as a parasitic magnetic ring) may be set on the ground plane <NUM>. In other words, the antenna apparatus provided in this application may further include a parasitic element. On the ground plane <NUM>, like the exciting element <NUM>, the parasitic element may be set in proximity to the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane. Herein, the proximity may mean that a distance between the parasitic element and the first side (for example, the lateral side <NUM>-<NUM>) of the ground plane is less than a specific distance (for example, <NUM>). In this case, a distance L3 from the parasitic element to the first side of the ground plane is less than a distance L4 from the parasitic element to the second side of the ground plane.

The parasitic element may have a same structure as the exciting element <NUM>. The parasitic element may have a third branch and two fourth branches. The third branch is similar to the first branch <NUM>-<NUM> in the exciting element <NUM>, and the fourth branches are similar to the second branches <NUM>-<NUM> and <NUM>-<NUM> in the exciting element <NUM>. Similar to the structure of the exciting element <NUM>, the two fourth branches in the parasitic element may be respectively connected to two ends of the third branch. An end of the fourth branch that is away from the first branch is connected to the ground plane <NUM>. The two fourth branches may be used to set the third branch on the ground plane <NUM>, so that a gap is formed between the third branch and the ground plane <NUM>. Like the exciting element <NUM>, a capacitor may be connected in series on the parasitic element. The capacitor may be referred to as a fifth capacitor. To connect the fifth capacitor in series, a gap may be disposed on the third branch, and the fifth capacitor may be connected in series between two parts of the third branch on both sides of the gap. The gap may be referred to as a second slot.

<FIG> and <FIG> show antenna performance at two matching network parameters. When the exciting element <NUM> is connected in series to the capacitor C=<NUM> pF, and connected in parallel to the inductor L=<NUM> nH, the length of the exciting element <NUM> is <NUM>, and the length of the parasitic element is <NUM>, S11 simulation of the antenna apparatus may be shown by curve a1 in <FIG>, and efficiency simulation of the antenna apparatus may be shown by curves b1 and c1 in <FIG>. It can be seen that the antenna apparatus operates in a dual-band: an <NUM> band and a <NUM> band, the two bands have basically same antenna efficiency, and have no efficiency dent. When the exciting element <NUM> is connected in series to the series capacitor C=<NUM> pF, and connected in parallel to the inductor L=<NUM> nH, the length of the exciting element <NUM> is <NUM>, and the length of the parasitic element is <NUM>, S11 simulation of the antenna apparatus may be shown by curve a2 in <FIG>, and efficiency simulation of the antenna apparatus may be shown by curves b2 and c2 in <FIG>. It can be seen that the antenna apparatus operates in a dual-band: an <NUM> band and a <NUM> band, the two bands have basically same antenna efficiency, and have no efficiency dent.

To cover more bands or a wider band, more parasitic magnetic rings may be disposed on the ground plane <NUM>, as shown in <FIG>. Specifically, three resonant frequencies can be implemented by using two parasitic magnetic rings; four resonant frequencies can be implemented by using three parasitic magnetic rings; and N+<NUM> resonant frequencies can be implemented by using N (N is a positive integer) parasitic magnetic rings. There is a series capacitor on each parasitic magnetic ring.

In addition to being disposed in proximity to lateral sides of the ground plane <NUM> shown in <FIG>, the exciting element <NUM> and the parasitic element or only the exciting element <NUM> may be disposed in proximity to the bottom side <NUM>-<NUM> or the top side <NUM>-<NUM> of the ground plane <NUM>, as shown in <FIG>. In other words, the first side of the ground plane may be a lateral side of the ground plane <NUM>, for example, the lateral side <NUM>-<NUM> or the lateral side <NUM>-<NUM>, or may be the bottom side <NUM>-<NUM> or the top side <NUM>-<NUM> of the ground plane <NUM>.

To implement multi input multi output (multi input multi output, MIMO), the antenna apparatus provided in this application may include a plurality of antenna elements. One antenna element may have one exciting element <NUM>, or may have one exciting element <NUM> and M (M is a positive integer) parasitic elements. The plurality of antenna elements may be disposed in proximity to the sides of the ground plane <NUM>. For example, as shown in <FIG>, four antenna elements may be respectively disposed in proximity to four sides of the ground plane <NUM>. In this case, 4x4 MIMO can be implemented. If two antenna elements in <FIG> are removed, 2x2 MIMO can be implemented. If more antenna elements are added in proximity to the ground plane in <FIG>, high-order MIMO can be implemented.

The parasitic element is not limited to the parasitic magnetic ring having the same structure as the exciting element <NUM>. To implement a multi-band or a wide-band, the parasitic element may alternatively be another antenna, such as a support antenna or a floating antenna. The support antenna may include an inverted F antenna (inverted F antenna, IFA), an inverted L antenna (inverted L antenna, ILA), and the like. <FIG> shows an example of a parasitic IFA antenna, <FIG> shows an example of a parasitic ILA antenna, and <FIG> shows an example of a parasitic floating metal antenna (floating metal antenna, FLM). The parasitic floating metal antenna may be affixed or printed on an inner surface or an outer surface of a non-metal back cover (for example, a glass back cover).

In some embodiments, the IFA may also serve as an exciting element, namely, the IFA is fed, and the IFA may couple energy to a magnetic ring having a same structure as the exciting element <NUM>. Then, the magnetic ring may couple energy to the ground plane, to excite the ground plane to generate radiation. In this case, a matching network of the IFA as an exciting element may be that a <NUM> pF capacitor is first connected in series, and then a 4nH inductor is connected in parallel. A <NUM> pF capacitor may be connected in series on the magnetic ring as a parasitic element. Similarly, the ILA may also serve as an exciting element, namely, the ILA is fed, and the ILA can couple energy to a magnetic ring having a same structure as the exciting element <NUM>. Then, the magnetic ring may couple energy to the ground plane, to excite the ground plane to generate radiation.

The capacitor and the inductor mentioned in the foregoing content of this application may be implemented by using a lumped element, or may be implemented by using a distributed element.

Claim 1:
An antenna apparatus of an electronic device (<NUM>), wherein the antenna apparatus comprises a ground plane (<NUM>) and an exciting element (<NUM>) of the electronic device (<NUM>), wherein
the exciting element (<NUM>) has a first branch (<NUM>-<NUM>) and two second branches (<NUM>-<NUM>, <NUM>-<NUM>), and the two second branches (<NUM>-<NUM>, <NUM>-<NUM>) are respectively connected to two ends of the first branch (<NUM>-<NUM>); an end of each second branch (<NUM>-<NUM>, <NUM>-<NUM>) that is away from the first branch (<NUM>-<NUM>) is connected to the ground plane; the two second branches (<NUM>-<NUM>, <NUM>-<NUM>) are used to set the first branch (<NUM>-<NUM>) on the ground plane (<NUM>), and a gap is formed between the first branch (<NUM>-<NUM>) and the ground plane (<NUM>);
the ground plane (<NUM>) comprises a first side and a second side that are opposite to each other, and a third side and a fourth side that are opposite to each other, wherein L1 is less than L2, L1 is a distance from the exciting element (<NUM>) to the first side of the ground plane (<NUM>), and L2 is a distance from the exciting element (<NUM>) to the second side of the ground plane (<NUM>); wherein p1 is a distance from a first end of the exciting element (<NUM>) to the third side, and p2 is a distance from a second end of the exciting element (<NUM>) to the fourth side of the ground plane (<NUM>); and the first end of the exciting element (<NUM>) is an end close to the third side, and the second end of the exciting element (<NUM>) is an end close to the fourth side; and
a feeding port (<NUM>) is disposed on the exciting element (<NUM>), a first slot is disposed on the first branch (<NUM>-<NUM>), and a first capacitor is formed by the first slot between two parts of the first branch (<NUM>-<NUM>),
wherein p1 is equal to p2,
wherein the feeding port (<NUM>) is disposed on a second branch.