Patent Description:
In recent years, in mobile terminals with a metal frame appearance, an antenna form of a planar inverted-F antenna (PIFA) is often used to design a WIFI antenna, a GPS antenna, a 4X4 multiple-input multiple-output (MIMO) antenna, or the like. Its structural design form is shown in <FIG>. <NUM> is a metal frame, and <NUM> is a reference ground. There is a gap <NUM> between <NUM> and <NUM>, and the gap <NUM> is filled with a non-metal material such as plastic. <NUM> is a flexible printed circuit ( FPC) or an antenna sheet produced through a laser-direct-structuring (LDS) process. A non-metal material such as plastic is also filled between <NUM> and <NUM>. <NUM> is a signal source and feeds electricity to the antenna <NUM> generally through the feed point <NUM> (a connection form can be a spring). Meanwhile, the antenna sheet <NUM> is grounded through the grounding point <NUM>. Finally, the common PIFA antenna form is achieved. In addition, the metal frame <NUM> generally has two grounding points <NUM> and <NUM> at both ends of the antenna sheet <NUM>, and a spring is generally used to achieve the connection, to achieve desirable grounding of the metal frame <NUM> in the antenna region to reduce impact on the antenna.

Because internal space of the mobile terminal is very limited, the height between the antenna sheet <NUM> and the reference ground <NUM> is very short and is generally <NUM> to <NUM> and is typically <NUM>. At the same time, the height from the antenna sheet <NUM> to a plane of an edge of the metal frame <NUM> near the back cover of the mobile terminal is about <NUM>. That is, the height of the PIFA antenna is very short. As can be seen from the basic theory of antennas, the antenna efficiency is very low. Generally, the average efficiency of the WIFI <NUM> antenna is less than <NUM>%. In addition, the FPC or the antenna produced through the LDS process is used. As a result, costs are also increased. <CIT> relates to an antenna. The antenna comprises a framework for mobile objects, a shell or a metal frame of a metal side frame, a plastic block positioned in the metal frame and a coaxial cable, wherein a radiation metal circuit is molded on the plastic block; the coaxial cable and the radiation metal circuit are welded together; the metal frame is partial to high-frequency radiation; the radiation metal circuit is partial to low-frequency radiation; the metal frame is an uninterrupted metal frame; the metal frame comprises a front end side, a rear end side and opposite two sides connecting the front end side with the rear end side, wherein the radiation metal circuit and the front end side make contact. <CIT> discloses an antenna combined with a terminal housing. The disclosed antenna includes an outer frame radiator, which is joined to a side wall of the terminal housing, and an inner frame radiator, which has one end joined to a first point on the outer frame radiator and the other end joined to a second point on the outer frame radiator, and which forms a loop by joining the outer frame radiator, where a feed signal is provided to the inner frame radiator. <CIT> discloses a portable electronic device including a housing, a substrate, a radiation conductor and a short circuit conductor. The housing defines an accommodating space and includes a frame that has a body portion and a radiation portion. The substrate is disposed in the accommodating space, is surrounded by the frame, and has a grounding portion. The radiation conductor is disposed in the accommodating space, is electrically coupled to the radiation portion, and includes a feed-in point. The short circuit conductor is electrically coupled between one end of the radiation portion and the grounding portion. <CIT> discloses a wireless communication device including a metal frame, a mechanical part on which a ground is formed for providing grounding, and at least one antenna, wherein each one of the at least one antenna includes a radiator, a feed terminal electrically connected to the radiator, disposed adjacent to the metal frame and for feeding a radio-frequency signal, a first ground terminal disposed at a first side of the feed terminal for electrically connecting the metal frame with the ground of the mechanical part, and a second ground terminal disposed at a second side of the feed terminal for electrically connecting the metal frame with the ground of the mechanical part, wherein an area enclosed by the metal frame, the mechanical part and the first and second ground terminals forms a first slot. <CIT> discloses an antenna structure including a feed portion, a ground portion, at least one metallic portion, and a radiating portion. The ground portion is spaced apart from the feed portion. The least one metallic portion is electrically connected to the ground portion. The radiating portion has a first end electrically connected to the feed portion and a second end electrically connected to the at least one metallic portion. <CIT> provides an annular loop closed metal ring antenna. The annular loop closed metal ring antenna comprises a feed wire and a closed meal ring side frame; the feed wire is electrically connected with a circuit board through a feed point and electrically connected with the closed metal side frame through a connecting point; two side edges of the closed metal ring side frame are respectively electrically connected to reference ground at the corresponding side edge of the circuit board through a first grounding point and a second grounding point; the fed wire, the closed metal ring side frame and the circuit board form first and second clearance areas; each of the first and second clearance areas comprises clearances which are formed between two side edges of the circuit board and the corresponding side edge of the closed metal ring side frame; the feed point enters the first and second clearance areas of the first and second grounding points through the connecting point to form first and second annular loops which have different resonance length.

The embodiments of the present disclosure provide a terminal device, to solve the problem that because internal space of the terminal device is limited, the antenna height is low in design, resulting in high device manufacturing costs and poor antenna efficiency.

To resolve the foregoing technical problem, the present disclosure is implemented as follows:
an embodiment of the present disclosure provides a terminal device, including:.

In the embodiments of the present disclosure, the first metal sheet connected to the metal frame is used as an antenna sheet, the metal frame is directly grounded, and a grounding connection device of the first metal sheet is omitted, thereby reducing the costs of the antenna. In addition, the first metal sheet is connected to the metal frame, and the part used as an antenna radiator also includes the metal frame in addition to the first metal sheet, which increases the area required by the antenna and improves the antenna radiation efficiency.

The following clearly and completely describes the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Apparently, the described embodiments are some rather than all of the embodiments of the present disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts shall fall within the protection scope of the present disclosure.

As shown in <FIG> is a structural schematic diagram of a terminal device according to an embodiment of the present disclosure. The terminal device includes: a metal frame <NUM>; a first metal sheet <NUM>, where a feed point <NUM> is disposed on the first metal sheet <NUM>, the first metal sheet <NUM> is connected to the metal frame <NUM>, and there is a first gap <NUM> between the metal frame <NUM> and a part of the first metal sheet <NUM> that is not connected to the metal frame <NUM>; and a grounding plate <NUM>, where the grounding plate <NUM> is connected to the metal frame <NUM> through a connection piece.

It should be noted that the grounding plate <NUM> is used as the antenna's reference ground, and includes: a main board and a metal plate with a preset area that is connected to the main board.

Herein, a plane of the first metal sheet <NUM> is roughly parallel to the grounding plate <NUM>, and the vertical distance between the first metal sheet <NUM> and the grounding plate <NUM> is greater than or equal to <NUM>. Being roughly parallel includes being parallel and being not parallel. Being not parallel refers to that the first metal sheet <NUM> slightly inclines relative to the grounding plate <NUM>, and an angle between an extending line of the first metal sheet <NUM> and a plane formed by the grounding plate <NUM> is small and smaller than a preset value. The preset value can be determined according to actual needs. Optionally, the vertical distance between the first metal sheet <NUM> and the grounding plate <NUM> is greater than <NUM>.

If the vertical distance from the first metal sheet <NUM> to the grounding plate <NUM> is H1, and the vertical distance from the side of the metal frame <NUM> close to the first metal sheet <NUM> to the grounding plate <NUM> is H2, H1 is greater than H2 minus <NUM>.

Further, the direction of the long side of the first metal sheet <NUM> is parallel to the direction of the long side of the metal frame <NUM>.

Herein, the terminal device also includes: a signal source <NUM>, one end of the signal source <NUM> is grounded, and the other end is connected to the feed point <NUM>. That is, the signal source <NUM> feeds electricity to the first metal sheet <NUM> through the feed point <NUM>. A connection manner includes: a spring, a screw, or the like.

Optionally, one end of the signal source <NUM> is connected to the grounding plate <NUM>.

It should be noted that the grounding plate <NUM> is connected to the metal frame <NUM> through a connection piece.

Because the grounding point of the first metal sheet <NUM> is changed to directly connect to the metal frame <NUM> and the grounding point of the first metal sheet <NUM> is closer to the frame of the metal frame <NUM>, antenna radiation is wider, thereby improving the antenna radiation efficiency. In addition, because the first metal sheet <NUM> is connected to the metal frame <NUM> and the metal frame <NUM> is grounded, a connecting device such as a grounding spring of the first metal sheet <NUM> for connecting to the ground can be omitted.

In the terminal device provided in the embodiments of the present disclosure, the first metal sheet is connected to the metal frame, and the metal frame is used as the part of an antenna radiator, which improves the antenna radiation efficiency. The first metal sheet connected to the metal frame is used as an antenna sheet, the antenna sheet is directly grounded through the metal frame, and a grounding connection device of the first metal sheet is omitted, thereby reducing the costs of the antenna.

Optionally, the metal frame <NUM> and the first metal sheet <NUM> are integrally formed.

Herein, the metal frame <NUM> is used to directly form the first metal sheet <NUM> through extension, to replace an FPC antenna or an LDS antenna through integral forming, thereby reducing costs. Moreover, due to integral forming design, a connection device such as a spring, or a screw between the metal frame <NUM> and the first metal sheet <NUM> is omitted, thereby further reducing the costs.

As an optional implementation, the metal frame <NUM> has a first protruded portion <NUM>, and the first protruded portion <NUM> is grounded.

Optionally, the first protruded portion <NUM> is connected to the grounding plate <NUM>.

Specifically, the connection piece includes: a first connection piece, and the first protruded portion <NUM> is connected to the grounding plate <NUM> through the first connection piece.

Further, as shown in <FIG> and <FIG>, the second metal sheet <NUM> is grounded through the first protruded portion <NUM>, that is, the grounding point of the second metal sheet <NUM> used as the antenna radiator is closer to the plate edge of the metal frame <NUM>. As can be seen from the basic principle of antennas, the radiation range of the antenna is wider, thereby further improving the antenna radiation efficiency.

Further, the metal frame <NUM> has a second protruded portion <NUM>, and the second protruded portion <NUM> is grounded. Herein, the second protruded portion <NUM> and the first protruded portion <NUM> are separated by a preset distance.

It should be noted that the first protruded portion <NUM> and the second protruded portion <NUM> are located on the same side of the metal frame <NUM>, that is, the side of the metal frame <NUM> close to the grounding plate <NUM>.

Optionally, the second protruded portion <NUM> is connected to the grounding plate <NUM>.

Specifically, the connection piece also includes: a second connection piece, and the second protruded portion <NUM> is connected to the grounding plate <NUM> through the second the connection piece.

Herein, a connection position at which the first protruded portion <NUM> is connected to the grounding plate <NUM> through the first connection piece is used as a first grounding point, and a connection position at which the second protruded portion <NUM> is connected to the grounding plate <NUM> through the second connection piece is used as a second grounding point. That is, there are two grounding points on the metal frame <NUM>.

Herein, optionally, there is a second gap between the metal frame <NUM> and the grounding plate <NUM>.

Further, the length of the second gap between the first protruded portion <NUM> and the second protruded portion <NUM> is greater than a <NUM>/<NUM> wavelength of an antenna operating frequency.

Herein, generally, the length of the second gap is less than the <NUM>/<NUM> wavelength of the antenna operating frequency (<NUM>/<NUM> wavelength changes with the change of the dielectric material around the antenna, for example, the dielectrics of air and plastic correspond to different <NUM>/<NUM> wavelengths). Alternatively, when the second gap is directly filled with a metal material, the radiation effect of the metal frame <NUM> is small, and the main effect is small inductance to the ground.

However, in this implementation, the length of the second gap between the first protruded portion <NUM> and the second protruded portion <NUM> is greater than a <NUM>/<NUM> wavelength of the antenna operating frequency, the second gap is filled with a non-metal material, and the metal frame <NUM> participates in radiation as a part of the antenna radiator, which can further improve the antenna radiation efficiency.

In an optional embodiment of the present disclosure, as shown in <FIG> and <FIG>, the terminal device also includes: a first metal arm <NUM> connected to the metal frame <NUM>; where the first metal sheet <NUM> is connected to the metal frame <NUM> through the first metal arm <NUM>.

In other words, the first metal arm <NUM> is also used as an antenna radiator and participates in the antenna radiation, thus increasing the area required by the antenna and improving the antenna radiation efficiency.

Optionally, the first metal arm <NUM> is disposed between the first protruded portion <NUM> and the second protruded portion <NUM>.

Based on this, to further improve the antenna radiation efficiency, the terminal device also includes: a second metal arm <NUM>, disposed between the feed point <NUM> and an end of the first metal sheet <NUM> away from the feed point <NUM>, and separately connected to the metal frame <NUM> and the first metal sheet <NUM>.

Optionally, the second metal arm <NUM> is provided between the first protruded portion <NUM> and the second protruded portion <NUM>.

It should be noted that the second metal arm <NUM> can be disposed close to the feed point <NUM> or away from the feed point <NUM>, and functions to adjust a resonance frequency of the antenna and participate in antenna radiation. Generally, being closer to the feed point <NUM> indicates a lower resonance frequency of the antenna; otherwise, a resonance frequency of the antenna is higher.

Herein, when the second metal arm <NUM> is disposed away from the feed point <NUM>, as shown in <FIG> and <FIG>, the terminal device also includes: a second metal sheet <NUM>, connected to an end of the first metal sheet <NUM> away from the feed point <NUM>, to ensure that resonance frequencies of the antenna are the same. Herein, the second metal arm <NUM> and the second metal sheet <NUM> are added to increase the area of the antenna, thereby effectively improving the antenna radiation efficiency.

In addition, the first metal arm <NUM> is disposed adjacent to the feed point <NUM>, and can be close to the grounding point on the metal frame <NUM> connected to the grounding plate <NUM> or close to the second metal arm <NUM>. The first metal arm <NUM> mainly functions to achieve impedance matching, and serve as an antenna radiator and participate in antenna radiation.

It should be noted that the first metal arm <NUM> and the second metal arm <NUM> are located on the same side of the metal frame <NUM>, that is, the side of the metal frame <NUM> close to the grounding plate <NUM>.

Optionally, the metal frame <NUM>, the first metal sheet <NUM>, the first metal arm <NUM>, the second metal arm <NUM>, and the second metal sheet <NUM> are integrally formed.

Herein, the metal frame <NUM> is used to directly form the first metal arm <NUM>, the second metal arm <NUM>, the first metal sheet <NUM>, and the second metal sheet <NUM> through extension, and the first metal arm <NUM>, the second metal arm <NUM>, the first metal sheet <NUM>, and the second metal sheet <NUM> are used as antenna radiators, to replace an FPC antenna or an LDS antenna through integral forming, thereby reducing costs. Moreover, due to integral forming design, a connection device such as a spring, a screw, or direct welding between the metal frame <NUM> and the first metal sheet <NUM> is omitted, thereby further reducing the costs.

Optionally, the second gap is filled with a non-metal material or a metal material. Optionally, a non-metal material is filled between the first metal sheet <NUM> and the grounding plate <NUM>.

In an example, if the antenna of the terminal device includes a WIFI <NUM> antenna, the vertical distance between the first metal sheet <NUM> and the grounding plate <NUM> is <NUM>, the length and the width of the first metal sheet <NUM> are about <NUM>*<NUM>, the vertical distance between the first metal sheet <NUM> and the plane of the long side of the metal frame <NUM> close to the back cover of the terminal is about <NUM>, the distance between one end of the first metal sheet <NUM> and a corresponding grounding point of the metal frame <NUM> is <NUM>, the distance between the other end of the first metal sheet <NUM> and another corresponding grounding point of the metal frame <NUM> is <NUM>, the distance between the first metal arm <NUM> and the second metal arm <NUM> is about <NUM>, and the distance between the two ground points of the metal frame <NUM> is about <NUM>.

The terminal device in the embodiments can significantly improve the antenna radiation efficiency, and the average antenna radiation efficiency can reach <NUM>%.

As shown in <FIG>, as an optional implementation, the terminal device can also include: a metal support bracket <NUM>, where the metal support bracket <NUM> is disposed around the first metal sheet <NUM> and is separately connected to the metal frame <NUM> and the grounding plate <NUM>; and a dual-camera module <NUM> fastened on the metal support bracket <NUM>.

It should be noted that the metal support bracket <NUM> is disposed around the first metal sheet <NUM> to meet the requirement on structural strength.

Herein, the metal support bracket <NUM> can be integrally formed with the metal frame <NUM> and the first metal sheet <NUM>, and the vertical height of the metal support bracket <NUM> is basically the same as that of the first metal sheet <NUM>.

A connection position at which the metal support bracket <NUM> is connected to the grounding plate <NUM> is used as the third grounding point <NUM>, so that the metal support bracket <NUM> can be grounded well, thereby reducing absorption of the antenna radiation efficiency by the metal support bracket <NUM>. The requirement on structural strength is met while ensuring that the performance of the antenna basically does not decrease.

In the above embodiments, the terminal device can be a mobile phone, a navigation device, a tablet computer, a personal digital assistant (PDA), a laptop computer, or the like.

Claim 1:
A terminal device, comprising:
a metal frame (<NUM>);
a first metal sheet (<NUM>), wherein a feed point (<NUM>) is disposed on the first metal sheet (<NUM>), the first metal sheet (<NUM>) is connected to the metal frame (<NUM>),
there is a first gap (<NUM>) between the metal frame (<NUM>) and a part of the first metal sheet (<NUM>) that is not connected to the metal frame (<NUM>); and
the terminal device further comprises a grounding plate (<NUM>), wherein the grounding plate (<NUM>) is connected to the metal frame (<NUM>) through a connection piece;
the terminal device further comprises a metal arm (<NUM>), disposed between the feed point (<NUM>) and an end of the first metal sheet (<NUM>) away from the feed point (<NUM>), and separately connected to the metal frame (<NUM>) and the first metal sheet (<NUM>);
characterized in that,
the terminal device further comprises a second metal sheet (<NUM>), connected to an end of the first metal sheet (<NUM>) away from the feed point (<NUM>).