Terminal equipment and method for controlling antenna direction

Abstract

The invention provides terminal equipment and a method for controlling the direction of an antenna. The terminal equipment comprises a feed source; a ground plane; the annular radiator is located on a back shell of the terminal equipment, the annular radiator is provided with a feeding point, a first connecting point and a second connecting point, the first connecting point and the second connecting point are located on the two sides of the feeding point, and the feeding point is connected with the feed source; the switching circuit is connected with the first connection point and the second connection point, when the switching circuit is in a first working state, the first connection point is connected with the ground plane, the second connection point is disconnected with the ground plane, the annular radiator has a first polarization direction, and when the switching circuit is in a second working state, the first connection point is disconnected with the ground plane. The second connection point is connected with the ground plane, and the annular radiator has a second polarization direction; the control circuit is used for adjusting the working state of the switching circuit according to the posture of the terminal device, so that the polarization direction of the annular radiator is matched with the polarization direction of the target communication signal. According to the embodiment of the invention, the polarization mismatch loss can be reduced.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of wireless communication technology, and more specifically, to a terminal device and a method for controlling the direction of an antenna. Background Art

[0002] Currently, high-end mobile phones and watches in terminal devices widely use dual-frequency positioning of the Global Positioning System (GPS), but most of them use linear polarization antennas. The design of a few circularly polarized antenna devices is more complicated and occupies a large space. GPS antennas often only guarantee the performance of the upper hemisphere. As the user's posture changes and the terminal device is placed in different directions, the quality of the received GPS signal is often poor, affecting the GPS positioning accuracy. Summary of the invention

[0003] The embodiment of the present application provides a terminal device and a method for controlling the direction of an antenna. The following introduces various aspects involved in the embodiment of the present application.

[0004] In a first aspect, a terminal device is provided, comprising: a feed source; a ground plane; a ring radiator, located at a back shell of the terminal device, the ring radiator having a feeding point, and a first connection point and a second connection point respectively located on both sides of the feeding point, the feeding point being connected to the feed source; a switching circuit, connected to the first connection point and the second connection point, when the switching circuit is in a first working state, the first connection point is connected to the ground plane, and the second connection point is disconnected from the ground plane, the ring radiator has a first polarization direction, when the switching circuit is in a second working state, the first connection point is disconnected from the ground plane, and the second connection point is connected to the ground plane, the ring radiator has a second polarization direction; a control circuit, connected to the switching circuit, for adjusting the working state of the switching circuit according to the posture of the terminal device, so that the polarization direction of the ring radiator matches the polarization direction of the target communication signal.

[0005] In a second aspect, a method for controlling the direction of an antenna is provided, which is applied to a terminal device, wherein the terminal device comprises: a feed source; a ground plane; a ring radiator, located on a back shell of the terminal device, the ring radiator having a feed point, and a first connection point and a second connection point, respectively located on both sides of the feed point, the feed point being connected to the feed source; a switching circuit, connected to the first connection point and the second connection point, when the switching circuit is in a first working state, the first connection point is connected to the ground plane, and the second connection point is disconnected from the ground plane, the ring radiator has a first polarization direction, when the switching circuit is in a second working state, the first connection point is disconnected from the ground plane, and the second connection point is connected to the ground plane, the ring radiator has a second polarization direction; a control circuit, connected to the switching circuit; the method comprises: determining the posture of the terminal device; adjusting the working state of the switching circuit according to the posture of the terminal device, so that the polarization direction formed by the ring radiator matches the polarization direction of the target communication signal.

[0006] According to a third aspect, a non-volatile computer-readable storage medium is provided, on which instructions for executing the method according to the second aspect are stored.

[0007] According to a fourth aspect, a computer program or a computer program product is provided, comprising instructions for executing the method according to the second aspect.

[0008] The embodiment of the present application adjusts the working state of the switching circuit according to the posture of the terminal device, so that the circular polarization direction of the antenna formed by the annular radiator can be changed, so that the terminal device has good polarization characteristics in various postures, which matches the polarization direction of the target communication signal, and helps to reduce polarization mismatch losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of some component units of a terminal device provided in an embodiment of the present application.

[0010] Figure 2 yes Figure 1 A structural schematic diagram of a possible implementation method of the ring radiator in FIG.

[0011] Figure 3 yes Figure 2 Schematic diagram of a possible beam direction of a ring radiator.

[0012] Figures 4a-4d yes Figure 2 Schematic diagram of the polarization current direction of a ring radiator at different phases.

[0013] Figure 5 It is a schematic diagram of an elliptically polarized wave.

[0014] Figure 6 yes Figure 3 Schematic diagram of the axial ratio of a ring radiator changing with Theta.

[0015] Figure 7 yes Figure 3 Schematic diagram of the circular polarization gain of a ring radiator when Phi = 90°.

[0016] Figure 8 yes Figure 1 A schematic structural diagram of another possible implementation of a terminal device.

[0017] Fig. 9 It is a flow chart of a method for controlling antenna direction provided in an embodiment of the present application.

[0018] Fig.10 yes Fig. 9 A flowchart of a possible implementation of the method. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0020] It should be understood that the technical solutions of the embodiments of the present application can be applied to various communication systems, such as: global system of mobile communication (GSM) system, code division multiple access (CDMA) system, wideband code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WIMA) communication system, fifth generation (5G) system or new radio (NR), etc. The technical solutions provided in the present application can also be applied to future communication systems, such as the sixth generation mobile communication system, satellite communication system, etc.

[0021] The terminal device in the embodiment of the present application may also be referred to as a terminal, user equipment (UE), user terminal, access terminal, user unit, user station, mobile station, mobile station (MS), mobile terminal (MT), remote terminal, remote station, mobile device, wireless communication device, user agent or user device. The terminal device in the embodiment of the present application may be a device that provides voice and / or data connectivity to a user, and may be used to connect people, objects and machines, such as a handheld device with wireless connection function, a vehicle-mounted device, etc. The terminal device in the embodiment of the present application can be a mobile phone, a tablet computer, a laptop computer, a PDA, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. Optionally, the UE can be used to act as a base station. For example, the UE can act as a scheduling entity that provides sidelink signals between UEs in V2X or D2D, etc. For example, a cellular phone and a car communicate with each other using a sidelink signal. The cellular phone and the smart home device communicate with each other without relaying the communication signal through the base station.

[0022] Linear polarized antennas usually occupy a small space and are easy to arrange. In terminal devices represented by mobile phones, most antennas are linearly polarized. The polarization of an antenna refers to the direction in which the end of the electric field vector radiated by the antenna changes with time in free space. The end trajectory of the linearly polarized electric field vector changes with time as a straight line. Linearly polarized electromagnetic waves are prone to attenuation and distortion during transmission. The maximum signal can only be obtained when the transmitter and receiver have the same polarization direction. This is almost impossible to achieve in actual communication, so it will cause polarization mismatch and affect the communication effect. Furthermore, linearly polarized antennas are difficult to suppress multipath interference. When electromagnetic waves propagate through trees, buildings or cloudy and rainy weather, they will be scattered when they encounter obstacles. The scattered electromagnetic waves and direct waves are received by the antenna together, causing the signal to be distorted. This is multipath interference. In addition, linearly polarized antennas are also difficult to avoid the Faraday rotation effect. The polarization direction of linearly polarized waves will rotate when passing through the ionosphere, which is easy to cause signal loss.

[0023] Compared with linearly polarized waves, circularly polarized waves have the characteristics of anti-attenuation and anti-interference, so they are widely used in navigation and the emerging satellite communications. There are two ways to realize circularly polarized antennas: one is to form circular polarization with a ring current whose effective circumference is an integer multiple of the wavelength; the other is to form circular polarization with two equal-amplitude orthogonal line currents with a phase difference of 90°. However, in order to realize the circular polarization design in the related technology, the design of the antenna device is more complicated, and the antenna device cannot be miniaturized.

[0024] Currently, high-end mobile phones and watches widely use dual-frequency positioning of the global positioning system GPS (i.e., L1 and L5), but most of them are linearly polarized antennas with poor communication quality. The center frequency of the GPS L1 band is 1575.25MHz, and the center frequency of the GPS L5 band is 1176.45MHz. The mobile phone GPS antennas on the market often only guarantee the upper hemisphere share performance. When the user lays the phone flat or upside down, the energy share of the GPS antenna towards the satellite in the sky cannot be guaranteed. Therefore, as the user's posture changes and the terminal device is placed in different directions, the quality of the received GPS signal is often poor, affecting the GPS positioning accuracy.

[0025] Since the direction of circular polarization is determined by both the current conduction direction and the electromagnetic wave radiation direction. Assuming that the right-hand circularly polarized antenna is viewed from the front to the back (i.e., from the back cover to the outside), it will be transformed into a left-hand circularly polarized antenna when viewed from the back to the front (i.e., from the display screen to the outside). However, left-hand circular polarization and right-hand circular polarization are completely mismatched, which also means that when the user scenario is with the display screen facing upward, the antenna can hardly receive GPS signals due to polarization mismatch, which will greatly affect the positioning accuracy of the terminal device.

[0026] It can be seen that the GPS antenna of the current terminal equipment often has the problem of polarization mismatch during use. Therefore, it is necessary to design an antenna with variable polarization direction so that the terminal can receive right-hand circularly polarized waves in different postures.

[0027] It should be noted that the above-mentioned problem of polarization mismatch and poor signal quality in the mobile phone GPS antenna is only an example, and the embodiments of the present application can be applied to any type of scenario in which the antenna of the terminal device has polarization mismatch.

[0028] Based on this, an embodiment of the present application proposes a terminal device. In the embodiment of the present application, a circularly polarized antenna is designed on the back shell (such as the back side of the battery cover), and the reflection effect of the large-sized metal front shell on the electromagnetic waves can be used to achieve in-phase superposition in the far field. Therefore, the circularly polarized antenna has good directional gain on the back side of the shell, which can meet the high gain requirements of the antenna in GPS communication / satellite communication. Figure 1 This is a schematic diagram of some components of the terminal device provided in the embodiment of the present application. Figure 1 The terminal device of the embodiment of the present application is introduced in detail.

[0029] To facilitate the description of the relationship between multiple polarization directions, beam directions, and the like, the embodiment of the present application takes the surface where the display screen of the terminal device is located as the front surface, and the surface opposite to the display screen as the back surface. The direction of the display screen when placed vertically is the reference direction, and the vertical direction includes the up and down directions; the horizontal direction of the front and back vertically placed on the display screen is the positive and negative direction (or the front and back direction), and the direction of the left and right sides of the display screen parallel to the display screen is the left and right direction.

[0030] like Figure 1 As shown, the terminal device 100 may include: a feed source 110 , a ground plane 120 , a ring radiator 130 , a switch circuit 140 and a control circuit 150 .

[0031] The feed source 110 is used to provide an excitation signal to be emitted to the ring radiator 130 .

[0032] The ground plane 120 is also called a reference ground, a ground plane, or a ground plane.

[0033] The annular radiator 130 is located at the back shell of the terminal device. The annular radiator 130 has a feeding point 131, and a first connection point 132 and a second connection point 133 respectively located on both sides of the feeding point 131. The feeding point 131 is connected to the feed source 110. The feeding point is connected to the feed source through a feed line, and the feeding point is also the connection point between the feed line and the antenna. The feeding point is also called a feeding terminal or a feeding end; the connection point is also called a connection terminal, a connection end, an electrical connection end, a connection port, a connection pin, etc. The embodiments of the present application do not make any distinction between them.

[0034] The shape of the ring radiator 130 can be any one of the following shapes: a circular ring, an elliptical ring, a polygonal ring, or an irregular ring.

[0035] The annular radiator 130 is located on the back shell (such as the back side of the battery cover). In order to improve the antenna radiation efficiency, it is necessary to keep as far away from the ground plane 120 as possible. The terminal device is usually provided with a rear camera decorative ring, and the rear camera metal decorative ring itself is relatively large and has a certain height. In some implementations, the annular radiator 130 can be composed of a rear camera decorative ring. In this way, the existing structure can be utilized without adding new components. It is low-cost and easy to implement. It can also save the frame antenna space, which helps to improve the antenna radiation efficiency. In some embodiments, the annular radiator 130 is arranged on the battery cover of the terminal device and is not easily affected by the user's hand.

[0036] The switch circuit 140 is connected to the first connection point 132 and the second connection point 133. The switch circuit 140 can have two or more working states. When the switch circuit 140 is in the first working state, the first connection point 132 is connected to the ground plane 120, and the second connection point 133 is disconnected from the ground plane 120, and the annular radiator 130 has a first polarization direction. When the switch circuit 140 is in the second working state, the first connection point 132 is disconnected from the ground plane 120, and the second connection point 133 is connected to the ground plane 120, and the annular radiator 130 has a second polarization direction.

[0037] The switch circuit 140 may have various forms. For example, the switch circuit 140 may include a first single-pole single-throw switch and a second single-pole single-throw switch. The first single-pole single-throw switch is connected to the ground plane 120 and the first connection point 132; the second single-pole single-throw switch is connected to the ground plane 120 and the second connection point 133, and the circuit is simple and reliable. In some embodiments, the switch circuit 140 may also include a single-pole double-throw switch, the fixed end of the single-pole double-throw switch is connected to the ground plane 120, and the movable end is connected to the first connection point 132 and the second connection point 133 respectively.

[0038] The control circuit 150 is connected to the switch circuit 140, and is used to adjust the working state of the switch circuit 140 according to the posture of the terminal device, so that the polarization direction of the ring radiator 130 matches the polarization direction of the target communication signal. That is, the polarization direction of the ring radiator 130 matches the polarization direction of the target communication signal, and the beam direction of the ring radiator 130 is roughly the same as the beam direction of the target communication signal, which helps to improve the radiation performance and radiation efficiency of the antenna.

[0039] The target communication signal is usually a right-hand circularly polarized signal, and the target communication signal may be, for example, a GPS signal (L1, L5) and / or a satellite communication signal. In some implementations, the target communication signal may also be a WIFI signal or a Bluetooth signal.

[0040] The terminal device can be in a variety of different postures during use, such as vertical placement, front horizontal placement, front upper placement, back horizontal placement, back upper placement, etc. Usually the direction of the target communication signal is fixed, for example, the GPS signal is a right-hand circular polarization signal, and the direction comes from the upper hemisphere. If the posture of the terminal device changes, there will be a polarization mismatch problem between the annular radiator 130 and the target communication signal.

[0041] The posture of the terminal device can generally be determined by a built-in posture sensor (such as an acceleration sensor, a gravity sensor). In some implementations, before controlling the working state of the switch module according to the posture of the terminal device, the posture of the electronic device can be obtained through the posture sensor. The posture sensor can be, for example, a gyroscope. For example, the gyroscope sensor can be used to obtain the Euler angle of the posture of the mobile phone through the posture solution method, which represents the motion posture of the mobile phone.

[0042] In some implementations, when the switch circuit 140 is in the first working state, the feed source 110 feeds an excitation signal to the annular radiator 130 through the feed point 131, and viewed from the front side of the terminal device to the back side, a polarization current is excited on the annular radiator 130 to form a right-hand circular polarization antenna, and the first polarization direction is the right-hand circular polarization direction. When the switch circuit 140 is in the second working state, the feed source 110 feeds an excitation signal to the annular radiator 130 through the feed point 131, and viewed from the back side of the terminal device to the front side, a polarization current is excited on the annular radiator 130 to form a right-hand circular polarization antenna, and the second polarization direction is the right-hand circular polarization direction. That is, from the perspective of matching the polarization direction of the target communication signal, the first polarization direction and the second polarization direction are both right-hand circular polarization directions.

[0043] Compared with linear polarization antennas, the electric field strength vector of circular polarization antennas changes with time in a circular trajectory. It has the following advantages: 1) Circular polarization antennas can receive any polarization form of electromagnetic waves, are insensitive to polarization, reduce signal loss caused by polarization mismatch, and have strong anti-attenuation ability. 2) Circular polarization antennas have orthogonal rotation direction, which can suppress multipath interference. When the signal transmitted by the circular polarization antenna encounters an obstacle, its rotation direction will become opposite to the original, which will cause the rotation directions of the direct wave and the scattered wave to be exactly orthogonal, and there is a high degree of isolation between them, so only the direct wave can be received by the receiving antenna. 3) The circularly polarized wave is still a circularly polarized wave after the rotation of the ionization plane, which can avoid losses such as the Faraday rotation effect. According to the working state of the attitude adjustment switch circuit 140 of the terminal device, the polarization direction of the annular radiator 130 is always the right-hand circular polarization direction, and its beam direction points to the upper hemisphere, which can avoid polarization mismatch with the target communication signal.

[0044] The circumference of the annular radiator affects the radiation performance of the antenna. The circumference (effective electrical length) of the annular radiator 130 can be determined according to an integer multiple of the wavelength of the target communication signal, or the circumference of the annular radiator 130 can be determined according to an integer multiple of the wavelength of the signal in its operating frequency band. In some embodiments, the circumference of the annular radiator 130 can be 1 times, 2 times, or multiple times the wavelength of the target communication signal.

[0045] The positional relationship between the feed point 131 and the first connection point 132 on the annular radiator 130 also affects the radiation performance of the antenna. In some embodiments, the angle between the feed point 131 and the first connection point 132 on the annular radiator 130 is a preset angle; and / or, the angle between the feed point 131 and the second connection point 132 on the annular radiator 130 is a preset angle. Preferably, the preset angle is greater than 15° and less than 50°.

[0046] In some implementations, the feed point 131 may be connected to the feed source 110 via a first matching circuit. The first matching circuit may include, but is not limited to, any combination of one or more capacitors, resistors, inductors, switches, etc. This embodiment of the application is not limited to this.

[0047] In some implementations, the first connection point 132 and / or the second connection point 133 may be connected to the ground plane 120 via a second matching circuit. The second matching circuit may include, but is not limited to, any combination of one or more capacitors, resistors, inductors, switches, and other components. For example, a capacitor is loaded to the ground plane 120 at the first connection point 132 next to the feeding point 131, and the capacitor can change the current voltage and phase relationship, thereby playing a role in pulling charge.

[0048] In some implementations, the annular radiator 130 can be manufactured on the back shell of the terminal device using a printed circuit board (FPC), a laser printed metal structure (LDS), a direct pad printing process (PDS), or other processes, and the antenna manufactured can also achieve the same or similar effects.

[0049] In some implementations, the annular radiator 130 may be provided with a plurality of grounded electrical connection points, such as a third connection point connected to the ground plane 120. The number of grounding points may be adjusted according to application requirements, and the matching circuits of the grounding connection points may also be adjusted according to actual conditions.

[0050] The embodiment of the present application adjusts the working state of the switch circuit according to the posture of the terminal device, so that the circular polarization direction of the antenna formed by the ring radiator is variable, so that the terminal device has good polarization characteristics in various postures, matches the polarization direction of the target communication signal, and helps to reduce polarization mismatch loss. The circularly polarized antenna formed by the ring radiator has good back radiation gain, which helps to improve the signal quality of GPS positioning and satellite communication.

[0051] The terminal device of the embodiment of the present application is further described below in combination with some possible implementation methods of the embodiment of the present application.

[0052] Take the annular radiator of the embodiment of the present application for GPS L5 communication as an example for illustrative explanation. The center frequency of the GPS L5 frequency band is 1176.45MHz. In the traditional border antenna solution, the antenna size requirement is relatively large because of the low frequency. At present, the number of antennas and the space environment in 5G mobile phones are very tight. As an auxiliary positioning antenna, L5 has a relatively low priority, and the resulting antenna environment is also relatively poor. Under normal circumstances, the radiation efficiency of the antenna is only around -10dB.

[0053] Figure 2 yes Figure 1 A structural schematic diagram of a possible implementation method of the ring radiator in FIG. Figure 2 This is a front view from the display screen of the terminal device to the back. Figure 2 The terminal device of the embodiment of the present application is introduced in detail. Figure 2 The ring radiator is shown as a GPS L5 mobile phone antenna. The antenna not only has right-hand circular polarization characteristics, but also has good radiation efficiency and upper hemisphere directivity. To facilitate the description of multiple polarization directions, beam directions and the relationship between them, the embodiment of the present application takes the side of the mobile phone where the display screen is located as the front side, and the side opposite to the display screen as the back side.

[0054] like Figure 2 As shown, the annular radiator 230 is located on the back shell of the mobile phone 200. The annular radiator 230 has a feeding point 231, and a first connection point 232 and a second connection point 233 respectively located on both sides of the feeding point 231. The feeding point 231 is connected to a feed source through a feed line.

[0055] The annular radiator 230 is composed of a rear camera decorative ring, which can utilize the existing component structure, save the frame antenna space, and help improve the antenna radiation efficiency. The rear camera metal decorative ring itself is large in size and has a certain height, which helps to increase the distance between it and the ground plane. For example, Figure 2 In an embodiment, the distance between the bottom side of the metal decorative ring antenna and the PCB ground plane area can be set to 3.2 mm. In some embodiments, the antenna is arranged on the battery cover of the mobile phone, so that it is not easily affected by the user's hand holding.

[0056] The circumference of the ring radiator 230 may be the electrical length of one wavelength of the target communication signal.

[0057] The feeding point 231 can be directly connected to the feed source (signal source) through a 0 ohm resistor. A zero ohm resistor is also called a jumper resistor, which is used to replace the jumper. Two capacitors (C=2.2pF) connected in series are loaded to the ground plane at the first connection point 232 to play the role of pulling current. When the switching circuit is in the first working state, the first connection point 232 is connected to the ground plane, and the second connection point 233 is disconnected from the ground plane, and the feed source feeds the excitation signal to the annular radiator 230 through the feeding point 231. Looking from the front of the mobile phone to the back, a polarized current is excited on the annular radiator 230 to form a right-hand circular polarization antenna, and the first polarization direction is the right-hand circular polarization direction.

[0058] Figure 3 yes Figure 2 Schematic diagram of one possible radiation efficiency and pattern of a ring radiator. Figure 3 The switch circuit is in the first working state, and the annular radiator 230 is a schematic diagram of the radiation efficiency and the directional diagram of the right-hand circularly polarized antenna. Figure 3 As shown, the maximum directivity is 5.625dBi, of which the upper hemisphere accounts for -3.4dB (about 45.7%). The antenna efficiency is about -5.9dB, which is about 3-4dB higher than the efficiency of the traditional frame antenna. Therefore, from these two parameters, the annular radiator 230 has excellent radiation performance as a GPS L5 antenna.

[0059] Figures 4a-4d yes Figure 3 Schematic diagram of the polarization current direction of the ring radiator at different phases. When the switch circuit is in the first working state, the ring radiator 230 is used as a right-hand circularly polarized antenna. Figures 4a-4d The diagrams are schematic diagrams of the current distribution of the annular radiator 230 at different phases of 0°, 90°, 180°, and 270°. The small arrows around the annular radiator represent the direction of the current flow, and the large arrows inside the annular radiator point to the strong point of the current. Figures 4a to 4d As shown in the distribution of the current flow direction, the phase of the ring radiator differs by 90°, and the distribution of the strong points of the current differs by approximately 90°. The current of the ring radiator is distributed in a wavelength, and basically moves counterclockwise along the ring. Looking from the front of the phone to the back (i.e., from the inside of the battery cover to the outside), the right-hand rule is satisfied, that is, the radiation from the back of the battery cover is a right-hand circularly polarized wave.

[0060] In actual engineering applications, ideal circularly polarized waves do not exist, only elliptically polarized waves that are close to circular polarization. The industry usually uses the axial ratio to indicate the purity of the circular polarization of the radiated electric field. The axial ratio is defined as the ratio of the major axis to the minor axis of the ellipse. Figure 5It is a schematic diagram of an elliptically polarized wave. It can be understood that the axis ratio of an ideal circularly polarized wave is 0dB, and the axis ratio of an ideal linearly polarized wave is infinite. In engineering, antennas with an axis ratio less than 3dB are usually defined as circularly polarized antennas.

[0061] Figure 6 yes Figure 3 Schematic diagram of the change of the axial ratio of the ring radiator with the pitch angle (Theta). That is, when the switch circuit is in the first working state, looking from the front to the back of the terminal device, the axial ratio of the ring radiator as a right-hand circularly polarized antenna changes with Theta. Figure 6 The axial ratio curve in is the axial ratio curve of the antenna (i.e., the ring radiator) when the azimuth angle Phi = 90°. Figure 6 As shown, the total 3 dB axial ratio bandwidth of the circularly polarized antenna at two locations is about 40°, which is a good performance for a single antenna in a mobile phone.

[0062] Figure 7 yes Figure 3 Schematic diagram of circular polarization gain of a ring radiator when Phi = 90°. Figure 7 As shown in the figure, the right-to-left ratio is higher than 10dB at most angles, which shows good right-hand circular polarization performance.

[0063] The switch circuit has multiple working states. The above describes the performance of the ring radiator as a right-hand circularly polarized antenna when the switch circuit is in the first working state, viewed from the front of the mobile phone to the back. When the switch circuit is in the second working state, the ring radiator is also a right-hand circularly polarized antenna when viewed from the back of the mobile phone to the front. The performance of the ring radiator as a right-hand circularly polarized antenna is similar or the same when the switch circuit is in the first working state or the second working state, except that the rotation direction is different, and the detailed process is not repeated.

[0064] It should be understood that the beam directions described above are based on Figure 2 This is for the display screen placed vertically. When the posture (or orientation) of the terminal device (such as a mobile phone) changes, the directions of multiple beams will change accordingly.

[0065] The embodiment of the present application adopts the rear camera decorative ring as a circularly polarized antenna. The circularly polarized antenna has good radiation performance. As a GPS L5 antenna, the radiation efficiency is improved by about 4dB compared with the traditional frame antenna. Considering that the navigation satellite signal is a right-handed circularly polarized wave, the antenna of the embodiment of the present application has no polarization loss, but the traditional polarized antenna has a 3dB polarization loss, and the comprehensive calculation efficiency differs by 7dB, which helps to improve the positioning accuracy. The antenna of the embodiment of the present application has good back radiation gain and is very suitable as a satellite communication antenna. It is also low-cost and easy to implement. In some embodiments, it only needs to add a shrapnel and two matching circuits to achieve it. Using the metal ring decorative part of the camera as an antenna can help to greatly save the frame antenna space, improve the performance of the mobile phone antenna, and is not easy to cause a sharp deterioration in performance due to being held by the user during use.

[0066] The embodiment of the present application adjusts the working state of the switching circuit according to the posture of the terminal device, so that the direction of the circular polarization of the antenna formed by the annular radiator can be changed, which is convenient for the terminal device to have good polarization characteristics in various postures, helps to reduce polarization mismatch loss, and helps to improve the signal quality of GPS communication and satellite communication.

[0067] Figure 8 yes Figure 1 A schematic diagram of another possible implementation of a terminal device. Taking a mobile phone in a terminal device as an example, Figure 8 It is also a front view from the front of the phone's display screen to the back. Figure 8 As shown, the mobile phone 800 may include: a feed source 810, a ground plane 820, a ring radiator 830, a switch circuit 840 and a control circuit (not shown in the figure).

[0068] The annular radiator 830 is located at the rear housing of the terminal device. The annular radiator 830 has a feeding point 831 and a first connection point 832 and a second connection point 833 respectively located at two sides of the feeding point 831. The feeding point 831 is connected to the feed source 810.

[0069] The switch circuit 840 may include a first single-pole single-throw switch S1 and a second single-pole single-throw switch S2. The first connection point 832 is connected to the ground plane 820 through the first single-pole single-throw switch S1 and the capacitor C1. The second connection point 133 is connected to the ground plane 820 through the second single-pole single-throw switch S2 and the capacitor C2.

[0070] When the switch circuit 840 is in the first working state, the first single-pole single-throw switch S1 is turned on, and the second single-pole single-throw switch S2 is turned off, and the capacitor C1 is working. The feed source 810 feeds an excitation signal to the annular radiator 830 through the feeding point 831. As described above, from the front of the mobile phone to the back, a polarization current is excited on the annular radiator 830 to form a right-handed circularly polarized antenna, and the current rotates counterclockwise. The first polarization direction is the direction of the right-handed circularly polarized antenna. When the switch circuit 840 is in the second working state, the first single-pole single-throw switch S1 is turned off, and the second single-pole single-throw switch S2 is turned on, and the capacitor C2 is working. The feed source 810 feeds an excitation signal to the annular radiator 830 through the feeding point 831, and the current rotates clockwise. However, from the back of the mobile phone to the front, a polarization current is excited on the annular radiator 830 to form a right-handed circularly polarized antenna, and the second polarization direction is the right-handed circularly polarized direction.

[0071] The working state of the switch circuit 840 is adjusted according to the posture of the terminal device so that the direction of the beam formed by the annular radiator 830 matches the direction of the target communication signal. For example, when the display screen of the mobile phone is facing downward or tilted downward, that is, the back side is tilted upward, the switch circuit 840 can be adjusted to be in the first working state, the direction of the annular radiator 830 is right-hand circular polarization, which matches the right-hand circular polarization direction of the target communication signal, and the beam direction of the annular radiator points to the upper hemisphere. When the display screen of the mobile phone is facing upward or tilted upward, that is, the back side is tilted downward, the switch circuit 840 can be adjusted to be in the second working state, and when viewed from the back of the mobile phone to the front, the direction of the annular radiator 830 is still right-hand circular polarization, which matches the right-hand circular polarization direction of the target communication signal, and the beam direction of the annular radiator also points to the upper hemisphere.

[0072] It should be understood that the polarization direction is determined based on the direction from the front of the phone to the back, or based on the direction from the back of the phone to the front. The beam direction is based on Figure 2 For example, when the display screen is placed vertically, when the posture (or orientation) of the electronic device (such as a mobile phone) changes, the corresponding beam direction will change accordingly.

[0073] Combination of the above Figures 1 to 8 The device embodiment of the present application is described in detail. Figure 9-10 The method embodiment of the present application is described in detail. It should be understood that the description of the method embodiment corresponds to the description of the device embodiment, so the parts not described in detail can refer to the previous device embodiment.

[0074] Fig. 9 It is a flow chart of a method for controlling antenna direction provided in an embodiment of the present application. Fig. 9The method is applied to a terminal device. The terminal device includes: a feed source; a ground plane; a ring radiator, located at the back shell of the terminal device, the ring radiator having a feeding point, and a first connection point and a second connection point respectively located on both sides of the feeding point, the feeding point being connected to the feed source; a switching circuit, connected to the first connection point and the second connection point, when the switching circuit is in a first working state, the first connection point is connected to the ground plane, and the second connection point is disconnected from the ground plane, the ring radiator has a first polarization direction, when the switching circuit is in a second working state, the first connection point is disconnected from the ground plane, and the second connection point is connected to the ground plane, the ring radiator has a second polarization direction; a control circuit, connected to the switching circuit. Fig. 9 As shown, the method may mainly include steps S910 to S920, which are described in detail below.

[0075] It should be pointed out that the size of the serial numbers of the steps in the embodiments of the present application does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0076] In step S910, the posture of the terminal device is determined.

[0077] The posture of the terminal device can generally be determined by a built-in posture sensor (such as an acceleration sensor, a gravity sensor). In some implementations, before controlling the working state of the switch module according to the posture of the terminal device, the posture of the electronic device can be obtained through the posture sensor. The posture sensor can be, for example, a gyroscope. For example, the gyroscope sensor can be used to obtain the posture Euler angle of the mobile phone through the posture solution method, which represents the movement posture of the mobile phone. For example, the posture sensor can be used to determine whether the display screen of the terminal device is tilted upward or downward.

[0078] In step S920, the working state of the switch circuit is adjusted according to the posture of the terminal device so that the polarization direction formed by the ring radiator matches the polarization direction of the target communication signal.

[0079] For example, when the display screen of the mobile phone is facing downward or tilted downward, that is, the back side is tilted upward, the switch circuit can be adjusted to be in the first working state, and the direction of the annular radiator is right-hand circular polarization when viewed from the front of the mobile phone to the back, which matches the right-hand circular polarization direction of the target communication signal. When the display screen of the mobile phone is facing upward or tilted upward, that is, the back side is tilted downward, the switch circuit can be adjusted to be in the second working state, and the direction of the annular radiator is still right-hand circular polarization when viewed from the back of the mobile phone to the front, which matches the right-hand circular polarization direction of the target communication signal.

[0080] Optionally, the annular radiator is a rear camera decorative ring.

[0081] Optionally, the circumference of the annular radiator is determined according to an integer multiple of the wavelength of the target communication signal.

[0082] Optionally, the angle between the feed point and the first connection point on the annular radiator is a preset angle; and / or the angle between the feed point and the second connection point on the annular radiator is a preset angle. Preferably, the preset angle is greater than 15° and less than 50°.

[0083] Optionally, the switch circuit may include: a first single-pole single-throw switch connected to the ground plane and the first connection point; and a second single-pole single-throw switch connected to the ground plane and the second connection point.

[0084] Optionally, the shape of the annular radiator is any one of the following shapes: a circular ring, an elliptical ring, or a polygonal ring.

[0085] Optionally, the target communication signal is a GPS signal and / or a satellite communication signal.

[0086] Fig.10 yes Fig. 9 A flowchart of a possible implementation of the method. Fig.10 The method is applied to Figure 8 800 for mobile phone. Fig.10 As shown, the method may mainly include steps S1010 to S1050, which are described in detail below.

[0087] In step S1010, the posture of the mobile phone is determined. The posture sensor can be used to determine whether the display screen of the terminal device is facing upward or downward.

[0088] In step S1020, it is determined that the display screen is facing downward, that is, the display screen of the mobile phone is facing downward or tilted downward.

[0089] In step S1030, it is determined whether the display screen is facing upward, that is, the display screen of the mobile phone is facing upward or biased upward.

[0090] In step S1040, switch S1 is turned on and S2 is turned off. When the display screen of the mobile phone is facing downward or tilted downward, that is, the back side is tilted upward, the switch circuit can be adjusted to the first working state, that is, switch S1 is turned on and S2 is turned off. Looking from the front of the mobile phone to the back, the direction of the annular radiator is right-hand circular polarization, which matches the right-hand circular polarization direction of the target communication signal.

[0091] In step S1050, switch S1 is turned off and S2 is turned on. When the display screen of the mobile phone is facing upward or tilted upward, the switch circuit can be adjusted to the second working state, that is, switch S1 is turned off and S2 is turned on. Looking from the back of the mobile phone to the front, the direction of the annular radiator is still right-hand circular polarization, which matches the right-hand circular polarization direction of the target communication signal.

[0092] An embodiment of the present application also provides a non-volatile computer-readable storage medium having instructions stored thereon, the instructions being used to execute any of the methods described above.

[0093] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present disclosure is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a machine-readable storage medium, or transmitted from one machine-readable storage medium to another machine-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The machine-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0094] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments of the present disclosure can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present disclosure.

[0095] It should be understood that in the various embodiments of the present application, "first", "second", etc. are used to distinguish different objects rather than to describe a specific order. The size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0096] In the several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0097] In several embodiments provided in the present application, it should be understood that when a certain part is said to be "connected" or "connected" to another part, it means that the part can not only be "directly connected" but also "electrically connected" with another element intervening therebetween. In addition, the term "connected" also means that the part is "physically connected" and "wirelessly connected". In addition, when a certain part is said to "include" a certain element, unless otherwise stated, it means that the certain part can include another element, rather than excluding the other element.

[0098] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0099] In addition, each functional unit in each embodiment of the present disclosure may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0100] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A terminal device, characterized in that: include: Feeds; ground plane; an annular radiator, located at the rear shell of the terminal device, the annular radiator having a feeding point, and a first connection point and a second connection point respectively located at two sides of the feeding point, the feeding point being connected to the feed source; a switch circuit connected to the first connection point and the second connection point, wherein when the switch circuit is in a first working state, the first connection point is connected to the ground plane, and the second connection point is disconnected from the ground plane, and the annular radiator has a first polarization direction; and when the switch circuit is in a second working state, the first connection point is disconnected from the ground plane, and the second connection point is connected to the ground plane, and the annular radiator has a second polarization direction; A control circuit is connected to the switch circuit and is used to adjust the working state of the switch circuit according to the posture of the terminal device so that the polarization direction of the annular radiator matches the polarization direction of the target communication signal.

2. The terminal device according to claim 1, characterized in that: When the switch circuit is in the first working state, the feed source feeds an excitation signal to the annular radiator through the feeding point, and a polarization current is excited on the annular radiator to form a right-hand circular polarization antenna when viewed from the front side of the terminal device to the back side, and the first polarization direction is a right-hand circular polarization direction; When the switching circuit is in the second working state, the feed source feeds an excitation signal to the annular radiator through the feeding point, and viewed from the back side of the terminal device to the front side, a polarization current is excited on the annular radiator to form a right-hand circular polarization antenna, and the second polarization direction is a right-hand circular polarization direction.

3. The terminal device according to claim 2, characterized in that: The annular radiator is a rear camera decorative ring.

4. The terminal device according to claim 2, characterized in that: The circumference of the annular radiator is determined according to an integer multiple of the wavelength of the target communication signal.

5. The terminal device according to claim 2, characterized in that: The angle between the feeding point and the first connection point on the annular radiator is a preset angle; and / or the angle between the feeding point and the second connection point on the annular radiator is a preset angle, and the preset angle is greater than 15° and less than 50°.

6. The terminal device according to claim 2, characterized in that: The switch circuit comprises: a first single-pole single-throw switch connected to the ground plane and the first connection point; A second single-pole single-throw switch is connected to the ground plane and the second connection point.

7. The terminal device according to claim 2, characterized in that: The shape of the annular radiator is any one of the following shapes: a circular ring, an elliptical ring, or a polygonal ring.

8. The terminal device according to any one of claims 1 to 7, characterized in that: The target communication signal is a GPS signal and / or a satellite communication signal.

9. A method for controlling the direction of an antenna, characterized in that: Applied to a terminal device, the terminal device comprising: Feeds; ground plane; an annular radiator, located at the rear shell of the terminal device, the annular radiator having a feeding point, and a first connection point and a second connection point respectively located at two sides of the feeding point, the feeding point being connected to the feed source; a switch circuit connected to the first connection point and the second connection point, wherein when the switch circuit is in a first working state, the first connection point is connected to the ground plane, and the second connection point is disconnected from the ground plane, and the annular radiator has a first polarization direction; and when the switch circuit is in a second working state, the first connection point is disconnected from the ground plane, and the second connection point is connected to the ground plane, and the annular radiator has a second polarization direction; A control circuit connected to the switch circuit; The method comprises: determining a posture of the terminal device; The working state of the switch circuit is adjusted according to the posture of the terminal device so that the polarization direction formed by the annular radiator matches the polarization direction of the target communication signal.

10. A non-volatile computer-readable storage medium, characterized in that: A computer program is stored thereon, which is used to implement the method according to claim 9 when being executed.

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