Electronic device

Abstract

The invention discloses electronic equipment, and relates to the technical field of electronic products. The electronic equipment comprises a conductive frame body, a feed circuit, a tuning circuit and a lumped element, the conductive frame body comprises a first radiator, a second radiator and a third radiator, and the first radiator, the second radiator and the third radiator are sequentially arranged at intervals in the extension direction of the conductive frame body; a first breaking joint is arranged between the first radiating body and the second radiating body, and a second breaking joint is arranged between the second radiating body and the third radiating body; the first radiator comprises a feeding point, the feeding circuit is electrically connected with the feeding point, the tuning circuit is in bridge connection with the first breaking joint, and the lumped element is in bridge connection with the second breaking joint.

Description

Technical Field

[0001] The present application relates to the technical field of electronic products, and in particular to an electronic device. Background Art

[0002] With the development of modern communication technology, the performance, functions, and integration of terminal equipment are constantly improving to meet the increasingly rich and varied usage scenarios and user needs. The performance of metal frame antennas currently widely used in mobile terminals is generally restricted by the high integration and extreme appearance design of the equipment. With the continuous development of the fifth generation (5th Generation, 5G) mobile communication technology and the enrichment of communication scenarios, the number of antennas contained in terminal equipment is increasing to meet the ever-expanding operating frequency range. In this case, how to achieve the coexistence of multiple frequency bands on a single antenna and ensure the performance of each frequency band becomes particularly important.

[0003] In the related art, in order to achieve the coexistence of multiple frequency bands on a single antenna, it is proposed that the antenna can be switched between different frequency bands by optimizing the matching and switching logic of the antenna. However, in this way, the antenna can only work in one frequency band at the same time. If the coexistence of two frequency bands is forced without changing the antenna structure, the performance of both frequency bands will be poor. Summary of the invention

[0004] The present application provides an electronic device that is conducive to the coexistence of antennas in low frequency bands and satellite positioning frequency bands.

[0005] In a first aspect, the present application provides an electronic device, comprising a conductive frame, a feeding circuit, a tuning circuit and a lumped element, wherein the conductive frame comprises a first radiator, a second radiator and a third radiator, and the first radiator, the second radiator and the third radiator are sequentially arranged at intervals along an extension direction of the conductive frame, a first break is provided between the first radiator and the second radiator, and a second break is provided between the second radiator and the third radiator;

[0006] The first radiator includes a feeding point, the feeding circuit is electrically connected to the feeding point, the tuning circuit is connected across the first slit, and the lumped element is connected across the second slit.

[0007] In an embodiment of the present application, the conductive frame includes a first radiator, a second radiator and a third radiator, and the tuning circuit is connected across the first break, and the lumped element is connected across the second break. In this way, two relatively independent resonant frequencies can be generated in the low frequency band and the satellite positioning frequency band, which is conducive to the coexistence of the antenna in the low frequency band and the satellite positioning frequency band. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic diagram of the structure of a single radiator solution;

[0009] Figure 2 yes Figure 1 Schematic diagram of the equivalent circuit structure of the single radiator solution;

[0010] Figure 3 It is a structural diagram of the parasitic radiator scheme;

[0011] Figure 4 yes Figure 3 Schematic diagram of the equivalent circuit structure of the parasitic radiator scheme in FIG.

[0012] Figure 5 It is a structural diagram of the radiator jumper solution;

[0013] Figure 6 yes Figure 5 Schematic diagram of the equivalent circuit structure of the radiator jumper scheme;

[0014] Figure 7 It is one of the simulation schematic diagrams in the embodiment of the present application;

[0015] Figure 8 This is the second simulation schematic diagram in the embodiment of the present application;

[0016] Fig. 9 It is one of the structural schematic diagrams of the metal frame antenna in the electronic device in the embodiment of the present application;

[0017] Fig.10 yes Fig. 9 Schematic diagram of the equivalent circuit structure of the metal frame antenna in FIG.

[0018] Fig.11 This is the third simulation schematic diagram in the embodiment of the present application;

[0019] Fig.12 This is the fourth simulation schematic diagram in the embodiment of the present application;

[0020] Fig.13 This is the fifth simulation schematic diagram in the embodiment of the present application;

[0021] Fig.14 This is the sixth simulation schematic diagram in the embodiment of the present application;

[0022] Fig.15 This is the seventh simulation schematic diagram in the embodiment of the present application;

[0023] Fig.16 This is the eighth simulation schematic diagram in the embodiment of the present application;

[0024] Fig.17 This is the ninth simulation schematic diagram in the embodiment of the present application;

[0025] Fig.18 This is the tenth simulation schematic diagram in the embodiment of the present application;

[0026] Fig.19 This is the second structural schematic diagram of the metal frame antenna in the electronic device in the embodiment of the present application;

[0027] Fig. 20 yes Fig.19 Schematic diagram of the equivalent circuit structure of the metal frame antenna. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0029] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0030] In the following, in conjunction with the accompanying drawings, an electronic device provided by an embodiment of the present application is described in detail through specific embodiments and application scenarios.

[0031] In the related art, the structure of a common single-band metal frame antenna in a mobile terminal is as follows: Figure 1-2As shown. For a traditional inverted-F antenna (IFA), usually, the feeding point is located near the ground return end of the antenna radiator, and the tuning circuit is close to the end of the antenna radiator, which contains switching devices and corresponding lumped elements for tuning the operating frequency of the antenna. For example, when the antenna operates in a low frequency band (B28 / B5 / B8), the bandwidth of the antenna itself is difficult to cover the entire operating frequency band. It is necessary to use a switching circuit to turn on different lumped elements (capacitors or inductors) to adjust the operating frequency of the antenna, thereby obtaining better communication performance within the frequency band. In addition, the matching circuit placed between the RF end and the antenna feeding point can adjust the impedance matching of the antenna itself, further reduce the matching loss of the antenna, and improve the performance of the antenna.

[0032] The operating frequency of the low-frequency antenna in the mobile terminal is only 0.7-0.96GHz, and the free space performance of the antenna is mainly determined by the floor mode it can excite. Generally speaking, the free space efficiency of a low-frequency antenna depends on the proportion of the longitudinal current of the floor that it can excite, that is, the proportion of the current distributed along the long side of the device. The larger the proportion of the longitudinal current, the higher the intensity, and the better the uniformity of the current distribution, the stronger the longitudinal floor mode that the antenna can excite, and the higher the corresponding free space efficiency. Therefore, please refer to Figure 3-4 Adding additional parasitic radiation branches to the traditional IFA antenna solution can increase the radiation aperture of the antenna and increase the proportion of the longitudinal current in the floor. However, for low-frequency antennas, the energy that can be coupled to the parasitic radiation branches is limited, so it is difficult to significantly improve the free space efficiency of the antenna.

[0033] See also Figure 5-6 To improve the parasitic radiator solution, Figure 5-6 As shown in the figure, by connecting a tuning circuit across the gap between two radiating branches, the conduction of the corresponding lumped element is controlled by a switch device, thereby adjusting the operating frequency of the antenna. Compared with the single radiator solution and the parasitic radiator solution, this solution can better excite the longitudinal current of the floor, and the field distribution of the antenna radiator is more uniform.

[0034] Taking the low-frequency band antenna of a mobile terminal as an example, when the antenna is placed on the side of the whole device and the operating frequency is 0.75 GHz, the current distribution and field distribution of the single radiator solution, the parasitic radiator solution, and the radiator jumper solution are as follows: Figure 7 and Figure 8As shown. The radiator jumper scheme has better floor longitudinal current ratio and field distribution uniformity than the other two schemes, so its low-frequency performance is better. In addition, although the parasitic radiator scheme and the radiator jumper scheme each contain two sections of radiation branches, the principle is to evenly couple the energy to the additional antenna radiator and radiate through the largest possible antenna aperture. Therefore, although this type of antenna scheme can effectively improve the free space efficiency of the low-frequency antenna, except for the high-order modes and frequency-doubling resonances that the antenna itself can excite, it cannot rely on the existing feeding structure and tuning circuit to excite additional current modes, so it is impossible to achieve multi-band coexistence. When the multi-band coexistence state is achieved only by adjusting the matching circuit, excessive matching losses are often introduced, which in turn causes a decrease in antenna performance. Figures 1 to 6 The meanings of the reference numerals in the figure are respectively: 101, radiation branch; 102, break; 103, matching circuit; 104, tuning circuit; 105, radio frequency end (RF); 106, metal frame; 107, main ground; 108, parasitic radiation branch.

[0035] See also Figure 9-10 , an electronic device is provided for an embodiment of the present application, the electronic device comprising a conductive frame 200, a feeding circuit 300, a tuning circuit 400 and a lumped element 500, the conductive frame 200 comprising a first radiator 201, a second radiator 202 and a third radiator 203, and the first radiator 201, the second radiator 202 and the third radiator 203 are sequentially arranged at intervals along the extension direction of the conductive frame 200, a first break 204 is provided between the first radiator 201 and the second radiator 202, and a second break 205 is provided between the second radiator 202 and the third radiator 203;

[0036] The first radiator 201 includes a feeding point 206 , the feeding circuit 300 is electrically connected to the feeding point 206 , the tuning circuit 400 is connected across the first slit 204 , and the lumped element 500 is connected across the second slit 205 .

[0037] The conductive frame 200 may be a metal frame of an electronic device. The conductive frame 200 may be divided by opening a segment seam on the conductive frame 200 to form a radiator. For example, the first slit 204 and the second segment seam may divide the conductive frame 200 into three parts to form the first radiator 201, the second radiator 202 and the third radiator 203. The first radiator 201, the second radiator 202 and the third radiator 203 may be radiators of the same metal frame antenna. For ease of understanding, the feed circuit 300 may be the feed circuit 300 of the metal frame antenna, and the metal frame antenna is a metal frame antenna with multiple frequency bands.

[0038] The extension direction of the conductive frame 200 may refer to the direction of the frame of the conductive frame 200. Fig. 9 When the conductive frame 200 includes four frames, namely, an upper frame, a left frame, a lower frame and a right frame, and the four frames are sequentially connected, the extension direction of the conductive frame 200 may refer to: a direction extending sequentially along the path of “upper frame→left frame→lower frame→right frame→upper frame”, or a direction extending sequentially along the path of “upper frame→right frame→lower frame→left frame→upper frame”, or a direction extending sequentially along the path of “right frame→lower frame→left frame→upper frame→right frame”, etc.

[0039] The above tuning circuit 400 can be used to adjust the frequency response of the circuit to ensure that the circuit exhibits ideal performance within a specific frequency or frequency range. The tuning circuit 400 may include structures such as capacitors, inductors and / or switches. Specifically, the on-off combination of the cross-connected capacitor and inductor at the first gap 204 can be adjusted by a multi-way switch, thereby adjusting the operating frequency of the antenna within the low frequency band. The specific structure of the tuning circuit 400 depends on the requirements and conditions of the application.

[0040] The lumped element 500 may be a capacitor or an inductor. By connecting a fixed-value lumped element 500 across the second slit 205, energy can be coupled to the third radiator 203 through the second slit 205, thereby exciting an additional floor current mode and generating a new initial resonant frequency of the antenna.

[0041] The tuning circuit 400 being connected across the first slit 204 may mean that the tuning circuit 400 is arranged between the first radiator 201 and the second radiator 202 , and one end of the tuning circuit 400 is electrically connected to the first radiator 201 , and the other end of the tuning circuit 400 is electrically connected to the second radiator 202 .

[0042] Correspondingly, the lumped element 500 being connected across the second slit 205 may mean that the lumped element 500 is arranged across the second radiator 202 and the third radiator 203 , and one end of the lumped element 500 is electrically connected to the second radiator 202 , and the other end of the lumped element 500 is electrically connected to the third radiator 203 .

[0043] The above-mentioned feeding circuit 300 can be a feeding circuit 300 for various antennas, wherein the feeding circuit 300 can be a feeding circuit 300 capable of outputting antenna signals of more than two frequency bands. The antenna frequency band output by the feeding circuit 300 can be set as needed. In the related art, the operating frequency of low-frequency band communication is only 700-960MHz, and its signal is not easily affected by the surrounding environment. It has good transmission capability and a large communication coverage range, which provides basic communication guarantee for specific usage scenarios of mobile terminals (remote areas, complex environments, emergency communications, etc.). At the same time, in these specific usage scenarios, satellite positioning is often required, that is, using the communication frequency band (L1 / L2 / L5) corresponding to GPS, especially the L5 frequency band (1165-1195MHz), which is mainly used for positioning services in extreme scenarios and complex environments and to achieve high-precision navigation, etc. Generally speaking, due to the limitations of antenna size and number in terminal equipment, it is difficult to have the opportunity to set up a separate L5 frequency band antenna. Some devices even only support L1 and L2 frequency bands to achieve basic satellite positioning functions. The existing solution in the industry is to select an antenna with poor performance from the multiple low-frequency band antennas included in the terminal device, and merge the low-frequency band with the L5 band by adjusting the matching circuit 304 and the switch state of the antenna. However, due to their similar operating frequencies, the common low-frequency band antenna solution cannot coexist with the L5 band, that is, when the antenna works in the low-frequency band, the L5 band cannot be permanently resident, affecting the use scenarios and user experience of the mobile terminal.

[0044] See also Fig.11 , for the embodiment of this application Fig.11 The metal frame antenna shown in the figure is simulated to obtain the simulation schematic diagram of the initial S parameters. In the embodiment of the present application, the metal frame antenna in the embodiment of the present application is referred to as a multi-band coexistence solution, wherein the initial S parameter is |S11| at the antenna feeding point 206, and the S parameter is not subjected to impedance matching by the matching circuit 304. Among them, Fig.11 The solid line in the Figure 9-10 The initial impedance of the metal frame antenna is shown. Figure 5-6 The scheme shown is used as a reference and is indicated by a dotted line. S parameters are often used to indicate the impedance matching degree of an antenna. For an antenna having only a single feed point 206, when the antenna resonates, its |S11| curve will have a deeper pit at the corresponding frequency point. Fig.11 As shown in the figure, the main resonant frequencies of the two low-frequency antenna solutions appear around 0.76 GHz. Fig.11The multi-band coexistence scheme shown has an additional initial resonant frequency near 1.06 GHz, and can generate two relatively independent resonant frequencies in the frequency range of 0.6-1.2 GHz. This is also the basis for the antenna scheme to achieve coexistence between the low-frequency band and the satellite positioning band.

[0045] See also Fig.12 for Figure 9-10 The diagram shows the S parameter (|S11|) of the multi-band coexistence solution after the matching circuit 304 is shown. Fig.12 The solid line in the Figure 9-10 The multi-band coexistence solution shown optimizes the matching circuit 304 and the tuning circuit 400 in a way that the low frequency band (B28 / B5 / B8) and the GPS positioning frequency band (L5) coexist, and keeps the L5 frequency band resident when switching to the low frequency band, thereby achieving the coexistence of multiple frequency bands. Since the multi-band coexistence solution itself can generate two independent initial resonance points (0.76GHz and 1.06GHz), only a slight adjustment is needed during optimization to obtain good performance in both working frequency bands. In contrast, Figure 5-6 The solution shown is used as a reference for a single-band antenna solution. Due to the lack of an additional initial resonance point of the antenna, it is difficult to achieve good impedance matching when two frequency bands coexist through optimization of the matching circuit 304 and the tuning circuit 400.

[0046] Figure 9-10 The total efficiency curve of the multi-band coexistence high-performance metal frame antenna in the coexistence state of the B28 band and the L5 band is shown as follows Fig.13 The average total efficiency in the B28 band and the L5 band is shown in Table 1. Compared with the common radiator cross-connection solution (dashed line), Figure 9-10 The multi-band coexistence solution (solid line) shown in the figure not only improves the peak and average values ​​of the total antenna efficiency in the B28 band, but also achieves excellent antenna performance in the L5 band. The average total efficiency in the B28 band is 4.22dB higher than the radiator cross-connect solution, and its performance even exceeds that of the common independent L5 single-band antenna.

[0047] Table 1

[0048]

[0049] Figure 9-10 The current distribution of the multi-band coexistence scheme during operation is shown in Fig.14 As shown in Figure 1. 0.75 GHz and 1.18 GHz represent the current modes excited by the B28 and L5 frequency bands, respectively. Figure 5-6 The current distribution of the radiator cross-connection scheme shown in the figure shows that the current patterns of the two antenna schemes are basically the same in the low frequency band, but Figure 9-10 The multi-band coexistence scheme shown uses multiple antenna radiators and sets corresponding tuning circuits 400 and lumped elements 500 between adjacent antenna radiators, so that energy can be distributed more evenly to each antenna radiator and the radiation aperture of the antenna is increased. Therefore, the scheme excites the longitudinal floor current in a larger area on the side of the whole machine, thereby obtaining better low-frequency performance. For the current distribution of the L5 band of the multi-band coexistence scheme, since the second radiator 202 and the third radiator 203 contained therein simultaneously excite the longitudinal floor current in the opposite phase to the first radiator 201, the zero point of the floor current distribution is located at the first break 204.

[0050] based on Figure 9-10 The current distribution characteristics of the multi-band coexistence solution, the tuning circuit 400 for the low frequency band is set at the first slit 204, which can effectively adjust the working frequency of the antenna in the low frequency band, and is just at the zero point of the current distribution excited by the L5 frequency band, and the on and off of the switch and the corresponding lumped element 500 will not affect the coexistence state of the L5 frequency band. In addition, placing the lumped element 500 of a fixed value at the second slit 205 can not only effectively couple energy to the third radiator 203, but also avoid placing the tuning circuit 400 or variable components to have unnecessary effects on the permanent state of the L5 frequency band.

[0051] See also Fig.14 , Figure 9-10 When the metal frame antenna shown works in a low frequency band, the first radiator 201, the second radiator 202, and the third radiator 203 work together to stimulate the longitudinal current of the floor. Figure 9-10 When the metal frame antenna shown works in the L5 frequency band, the second radiator 202 and the third radiator 203 work together to stimulate the longitudinal current of the floor.

[0052] Figure 9-10 The field distribution of the metal frame antenna is shown as Fig.15 As shown. When the operating frequency is 0.75GHz, the uniformity of the field distribution of this solution is significantly better than the common radiator cross-connection solution. For low-frequency antennas, the greater the proportion of the longitudinal current it excites, the higher the intensity, and the better the uniformity of the current distribution, the stronger the floor longitudinal mode that the antenna can excite, and the higher the free space efficiency obtained. Therefore, the multi-band coexistence solution can not only achieve the coexistence of the low-frequency band and the satellite positioning band, but also its low-frequency band antenna efficiency is significantly improved compared to the radiator cross-connection solution and other common single-band antenna solutions.

[0053] In this embodiment, the conductive frame 200 includes a first radiator 201, a second radiator 202 and a third radiator 203, and the tuning circuit 400 is connected across the first slit 204, and the lumped element 500 is connected across the second slit 205. In this way, two relatively independent resonant frequency points can be generated within the frequency range of 0.6-1.2 GHz, which is conducive to the coexistence of the antenna in the low frequency band and the satellite positioning frequency band.

[0054] Optionally, the feeding circuit 300 includes a first feed source 301, a second feed source 302 and a signal extractor 303, the first feed source 301 is electrically connected to a first connection terminal 3031 of the signal extractor 303, the second feed source 302 is electrically connected to a second connection terminal 3032 of the signal extractor 303, and a third connection terminal 3033 of the signal extractor 303 is electrically connected to the feeding point 206.

[0055] The signal extractor 303 may be a signal extractor 303 capable of realizing signal separation in the related art, or a signal separator.

[0056] The frequency band of the signal output by the first feed source 301 is different from the frequency band of the signal output by the second feed source 302. In the process of the metal frame antenna receiving the signal, the signal extractor 303 can separate the received signal according to the frequency band, and transmit the separated signal to the power amplifier circuit of the corresponding frequency band to realize the signal reception process of the specific frequency band. Correspondingly, in the process of the metal frame antenna transmitting the signal, the signal extractor 303 can also separate the signal and transmit the separated signal to the first radiator 201 for signal transmission.

[0057] In this implementation, by providing a signal extractor 303, signals of different frequency bands can be separated by the signal extractor 303, thereby facilitating the coexistence of different frequency bands in the metal frame antenna.

[0058] Optionally, the feeding circuit 300 further includes a matching circuit 304 , and the third connection terminal 3033 of the signal extractor 303 is electrically connected to the feeding point 206 via the matching circuit 304 .

[0059] The main purpose of the matching circuit 304 is to ensure impedance matching between the signal source or device and the load to achieve maximum power transfer and minimum signal reflection. Impedance matching can be achieved by adjusting the values ​​of circuit elements to ensure that the output impedance of the signal source matches the input impedance of the load, thereby optimizing power transfer efficiency. The matching circuit 304 may include structures such as capacitors, inductors and / or transmission lines, and its specific structure depends on the needs and conditions of the application.

[0060] In this embodiment, a matching circuit 304 is provided between the third connection terminal 3033 of the signal extractor 303 and the feeding point 206. Thus, not only the impedance matching of the metal frame antenna can be achieved through the matching circuit 304, but also the matching circuit 304 can cooperate with the signal extractor 303 to achieve signal separation.

[0061] Optionally, the first feed source 301 is a low-frequency communication signal, and the second feed source 302 is a satellite positioning signal.

[0062] Among them, the low-frequency communication signal can be a communication signal with a frequency band between 0.7GHz and 0.96GHz. The above-mentioned satellite positioning signals can include L1 band, L2 band and L5 band, among which L1 band is the main signal band of the Global Positioning System (GPS), and its center frequency is 1575.42MHz. L2 band is the second main frequency band of GPS, and its center frequency is 1227.60MHz. L5 band is the latest frequency band introduced by GPS, and its center frequency is 1176.45MHz.

[0063] In this implementation, since the first feed source 301 is a feed source for low-frequency communication signals and the second feed source 302 is a feed source for satellite positioning signals, the above-mentioned multi-band coexistence solution is applied to the scenario where the satellite positioning band and the low-frequency band coexist.

[0064] Optionally, the low-frequency communication signal includes: a communication signal in the B28 frequency band, a communication signal in the B5 frequency band and a communication signal in the B8 frequency band, and the satellite positioning signal includes a satellite positioning signal in the L5 frequency band.

[0065] The frequency range of the B28 frequency band is 0.703 GHz to 0.803 GHz, the frequency range of the B5 frequency band is 0.824 GHz to 0.894 GHz, the frequency range of the B8 frequency band is 0.88 GHz to 0.96 GHz, and the frequency range of the L5 frequency band is 1.165 GHz to 1.195 GHz.

[0066] In an embodiment of the present application, the multi-way switch in the above-mentioned tuning circuit 400 can be controlled to achieve the switching of the low-frequency band of the above-mentioned metal frame antenna among the B28 band, the B5 band and the B8 band, and in the process of switching the low-frequency band of the metal frame antenna, the metal frame antenna can keep the L5 band in a permanent state.

[0067] The total efficiency curve of the metal frame antenna provided in the embodiment of the present application when the low frequency band (B28 / B5 / B8) and the satellite positioning frequency band (L5) coexist is as follows: Fig.16 By controlling the tuning circuit 400 placed at the first slit 204, the working frequency of the antenna can be switched and adjusted in the low frequency band. At the same time, the L5 band is little affected and always presents excellent antenna performance. The average total efficiency of the antenna is shown in Table 2.

[0068] Table 2

[0069]

[0070] Compared with the common radiator cross-connection solution, the metal frame antenna provided in the embodiment of the present application not only realizes the coexistence state of the low frequency band (B28 / B5 / B8) and the satellite positioning frequency band (L5), but also achieves a significant improvement in antenna performance. Since the metal frame antenna provided in the embodiment of the present application produces two relatively independent initial resonant frequencies, the matching circuit 304 required to achieve the coexistence state has a simpler topological structure and lower loss. The average total efficiency of the scheme in the L5 frequency band reaches -3.68dB, which is 3.74dB higher than the radiator cross-connection solution. At the same time, the average total efficiency of the scheme in the entire low frequency band has also been improved by 1.18dB, reaching -2.81dB.

[0071] The directivity of the metal frame antenna provided in the embodiment of the present application when the low frequency band (B28 / B5 / B8) and the satellite positioning frequency band (L5) coexist is as follows: Fig.17 When the antenna's operating frequency is switched within the low frequency band, the L5 band (1.18 GHz) remains stationary and its main radiation direction is located in the upper hemisphere, which is consistent with the requirements for the directional pattern of the satellite positioning scenario of the mobile terminal.

[0072] The Body-SAR-5mm-10g hotspot distribution of the metal frame antenna provided in the embodiment of the present application when working in the low frequency band is as follows Fig.18 For common low-frequency band antennas, their SAR (Specific Absorption Rate) values ​​must meet the corresponding mandatory requirements of regulations. Therefore, when the overall efficiency of the antenna is improved, the change in its SAR value must be considered at the same time to avoid the SAR value exceeding the standard due to the improvement of the overall efficiency of the antenna, and then the need to reduce the antenna's transmission power, which ultimately leads to a decrease in the antenna's OTA (Over-The-Air) performance.

[0073] Compared with the common radiator cross-connection solution, the metal frame antenna provided in the embodiment of the present application benefits from a larger number of antenna radiators, a larger radiation aperture and better field distribution uniformity. The distribution of its SAR hotspots is also more dispersed, which is conducive to obtaining better antenna OTA performance when the transmission power at the RF end is the same. As shown in Table 3, when the transmission power is 0.25W, the Body-SAR-5mm-10g of the multi-band coexistence solution at 0.75 / 0.86 / 0.92GHz is lower than that of the radiator cross-connection solution. When the difference in the total efficiency of the antenna is taken into account and the SAR value is normalized, the SAR value advantage of the multi-band coexistence solution in the low frequency band is more obvious.

[0074] Table 3

[0075]

[0076] The OTA performance of the metal frame antenna provided in the embodiment of the present application when working in the low frequency band is shown in Table 4. Generally speaking, the SAR value of the mobile terminal in the low frequency band should be used as a reference for the maximum value it can reach, and the transmission power of the antenna that exceeds the standard should be limited to meet the requirements of relevant regulations. For example, when the SAR value is controlled to not exceed 1.0, the antenna total efficiency of the multi-band coexistence solution is higher, but the reduction in transmission power is lower. The OTA performance gain of the multi-band coexistence solution before SAR reduction is 1.18dB (the same as the gain of the total efficiency of the low-frequency band antenna), but because the SAR value of the multi-band coexistence solution exceeds the standard less, the OTA performance gain of the solution after SAR reduction is 2.34dB. Overall, the antenna has obvious performance benefits in the low frequency band.

[0077] Table 4

[0078]

[0079] In this implementation, since the low-frequency communication signal includes: a communication signal in the B28 frequency band, a communication signal in the B5 frequency band, and a communication signal in the B8 frequency band, and the satellite positioning signal includes a satellite positioning signal in the L5 frequency band, the above-mentioned multi-band coexistence scheme is applied to the scenario where the L5 frequency band coexists with various low-frequency frequency bands.

[0080] Optionally, the length of the first radiator 201 , the length of the second radiator 202 , and the length of the third radiator 203 are equal.

[0081] The length of the first radiator 201 can be Figure 1-2In addition, the length of the second radiator 202 and the third radiator 203 should be kept consistent with the length of the first radiator 201 as much as possible, so as to obtain better field distribution uniformity in the low frequency band. Since the length of the second radiator 202 and the third radiator 203 will directly affect the initial resonant frequency point required to achieve the coexistence state, their lengths can be appropriately adjusted when necessary, but it should be ensured that two relatively independent resonant frequencies can be generated within the frequency range of 0.6-1.2 GHz.

[0082] In this implementation, by making the length of the first radiator 201, the length of the second radiator 202 and the length of the third radiator 203 equal, it is beneficial to obtain better field distribution uniformity in the low frequency band.

[0083] Optionally, the first radiator 201 , the second radiator 202 and the third radiator 203 are located in the same frame of the conductive frame 200 .

[0084] In this embodiment, compared with the first radiator 201, the second radiator 202 and the third radiator 203 being located in different frames, when the first radiator 201, the second radiator 202 and the third radiator 203 are located on the same side frame of the conductive frame 200, the metal frame antenna has better antenna performance.

[0085] It can be understood that, in some other embodiments of the present application, the first radiator 201 , the second radiator 202 and the third radiator 203 can also span different frames of the conductive frame 200 .

[0086] Optionally, the lumped element 500 is a capacitor, and a capacitance value of the capacitor is less than 5 pF.

[0087] In some embodiments of the present application, the capacitance value of the capacitor may be 1 pF. In other embodiments of the present application, the capacitance value of the capacitor may be 2 pF.

[0088] In this implementation, by making the capacitance value of the capacitor smaller than 5 pF, that is, by selecting a capacitor with a smaller capacitance value as the lumped element 500, it is helpful to reduce the current loss in the lumped element 500, thereby further improving the antenna performance.

[0089] Optionally, one end of the first radiator 201 away from the second radiator 202 is grounded, and one end of the third radiator 203 away from the second radiator 202 is grounded.

[0090] See also Fig. 9In some embodiments of the present application, the electronic device may further include a main ground 600, and the main ground 600 is connected to the conductive frame 200. One end of the first radiator 201 away from the second radiator 202 is connected to the main ground 600, and one end of the third radiator 203 away from the second radiator 202 is connected to the main ground 600 to achieve grounding of the first radiator 201 and the third radiator 203. The main ground 600 may be a metal plate located between the screen and the mainboard of the electronic device, and the main ground 600 may be used as the main ground of the entire electronic device.

[0091] In this embodiment, by grounding one end of the first radiator 201 away from the second radiator 202 and one end of the third radiator 203 away from the second radiator 202, the metal frame antenna can be ensured to work normally. Figure 9-10 The illustrated embodiment also has at least the following beneficial effects:

[0092] This embodiment introduces multiple antenna radiators and sets corresponding tuning circuits 400 and lumped elements 500 between two adjacent radiators, and places matching circuits 304 and signal extractors 303 between the antenna feed point 206 and the RF end, so as to achieve the coexistence of the low frequency band and the satellite positioning frequency band.

[0093] This implementation effectively improves the uniformity of the antenna field distribution and increases the radiation aperture of the antenna, increases the intensity and proportion of the longitudinal current in the floor, and achieves better low-frequency performance.

[0094] This implementation has a more dispersed SAR hotspot distribution. After limiting the SAR value according to relevant regulations, the antenna's OTA performance advantages are obvious.

[0095] Optionally, see Figure 19-20 The conductive frame 200 is also provided with a third slit 207, the first radiator 201 is located between the first slit 204 and the third slit 207, the feeding point 206 is located at one end of the first radiator 201 facing the third slit 207, and the end of the third radiator 203 away from the second radiator 202 is grounded.

[0096] In this embodiment, by introducing multiple antenna radiators and arranging corresponding tuning circuits 400 and lumped elements 500 between two adjacent radiators, the same as in the embodiment of the present invention can be obtained. Figure 9-10 The first radiator 201 is a suspended branch, and the feeding point 206 is located near the third slit 207, forming an antenna structure similar to a monopole. Figure 9-10Compared with the embodiment shown, it has at least the following beneficial effects:

[0097] Figure 19-20 The embodiment shown is relative to Figure 9-10 The illustrated embodiment expands the application scenarios of the antenna solution while ensuring the OTA performance of the antenna by applying the multi-band coexistence solution to the monopole antenna structure;

[0098] Figure 19-20 The embodiment shown is relative to Figure 9-10 In the illustrated embodiment, the antenna radiator where the antenna feed point 206 is located does not need to be provided with a ground return terminal, which provides additional freedom and solutions for the design of the metal frame antenna in the mobile terminal.

[0099] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. An electronic device, characterized in that: The invention comprises a conductive frame, a feeding circuit, a tuning circuit and a lumped element, wherein the conductive frame comprises a first radiator, a second radiator and a third radiator, and the first radiator, the second radiator and the third radiator are sequentially arranged at intervals along the extension direction of the conductive frame, a first break is provided between the first radiator and the second radiator, and a second break is provided between the second radiator and the third radiator; The first radiator includes a feeding point, the feeding circuit is electrically connected to the feeding point, the tuning circuit is connected across the first slit, and the lumped element is connected across the second slit.

2. The electronic device according to claim 1, characterized in that: The feeding circuit includes a first feed source, a second feed source and a signal extractor, the first feed source is electrically connected to the first connection end of the signal extractor, the second feed source is electrically connected to the second connection end of the signal extractor, and the third connection end of the signal extractor is electrically connected to the feeding point.

3. The electronic device according to claim 2, characterized in that: The feeding circuit further includes a matching circuit, and the third connection end of the signal extractor is electrically connected to the feeding point through the matching circuit.

4. The electronic device according to claim 2, characterized in that: The first feed source is a feed source for low-frequency communication signals, and the second feed source is a feed source for satellite positioning signals.

5. The electronic device according to claim 4, characterized in that: The low-frequency communication signals include: communication signals in the B28 frequency band, communication signals in the B5 frequency band and communication signals in the B8 frequency band, and the satellite positioning signals include satellite positioning signals in the L5 frequency band.

6. The electronic device according to claim 1, characterized in that: The length of the first radiator, the length of the second radiator and the length of the third radiator are equal.

7. The electronic device according to claim 1, characterized in that: The first radiator, the second radiator and the third radiator are located in the same frame of the conductive frame.

8. The electronic device according to claim 1, characterized in that: The lumped element is a capacitor, and the capacitance value of the capacitor is less than 5 pF.

9. The electronic device according to any one of claims 1 to 8, characterized in that: One end of the first radiator away from the second radiator is grounded, and one end of the third radiator away from the second radiator is grounded.

10. The electronic device according to any one of claims 1 to 8, characterized in that: The conductive frame is further provided with a third break, the first radiator is located between the first break and the third break, the feeding point is located at one end of the first radiator facing the third break, and one end of the third radiator away from the second radiator is grounded.

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