Antenna and electronic equipment

Abstract

The invention provides an antenna and electronic equipment, and the antenna comprises a radiation branch, the first end of the radiation branch is grounded, the second end is a free end, the radiation branch comprises a feeding point and a matching point, the matching point is located between the feeding point and the first end, the matching point is connected with a grounded oscillation circuit, and the feeding point is connected with a feeding circuit. And the feed circuit excites the radiation branch knot to generate resonance in low-frequency and medium-high-frequency bands. According to the embodiment of the invention, the grounded oscillation circuit can excite a plurality of resonance modes of the antenna, thereby widening the bandwidth of the antenna, enabling the antenna to cover low-frequency and medium-high-frequency bands at the same time, reducing the size of the antenna, not needing a tuning switch for frequency band switching, and reducing the cost and design difficulty.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of wireless radio frequency, in particular to an antenna and an electronic device. BACKGROUND

[0002] With the continuous development of wireless communication technology, the frequency bands required to be supported by mobile terminals are increasing, and the number of antennas is also increasing. How to realize the antenna layout design of multi-band fusion in limited device space has always been a design difficulty of mobile terminal antenna systems. SUMMARY

[0003] To realize the design of a low-cost and small-size multi-band fusion antenna, the embodiments of the present disclosure provide an antenna and an electronic device with the antenna.

[0004] In a first aspect, the embodiments of the present disclosure provide an antenna, comprising a radiation branch formed by a frame of an electronic device, a first end of the radiation branch being grounded, and a second end being a free end;

[0005] The radiation branch comprises a feeding point and a matching point, the matching point being located between the feeding point and the first end, the matching point being connected to an oscillation circuit, and the oscillation circuit being grounded; the feeding point is connected to a feeding circuit, the feeding circuit excites the radiation branch to generate a first resonance, and the first resonance comprises a low-frequency band and a medium-high-frequency band.

[0006] In some embodiments, the radiation branch is in an L-shaped structure, and the matching point is close to a bending position of the L-shaped structure.

[0007] In some embodiments, the feeding circuit comprises a first main branch, a first branch and a second branch, the first main branch has a first inductor, a first capacitor, a second inductor and a first feed source connected in series in sequence;

[0008] The first branch comprises a second capacitor and a third inductor, one end of the second capacitor is connected between the first inductor and the first capacitor, the other end of the second capacitor is connected to the third inductor, and the third inductor is grounded;

[0009] The second branch comprises a third capacitor, one end of the third capacitor is connected between the second inductor and the first feed source, and the other end of the third capacitor is grounded.

[0010] In some embodiments, a tuning switch circuit is further included, the tuning switch circuit is connected between the feeding circuit and the feeding point, and the tuning switch circuit is configured to adjust the resonance frequency of the first resonance by switching different tuning branches.

[0011] In some embodiments, the feeding circuit includes a second main branch and a third branch, and the fourth capacitor, the fifth capacitor and the second feeding source are connected in series on the second main branch.

[0012] The third branch includes a fourth inductor and a sixth capacitor, one end of the fourth inductor is connected between the fourth capacitor and the feeding point, and the other end of the fourth inductor is connected to one end of the sixth capacitor, and the other end of the sixth capacitor is grounded.

[0013] In some embodiments, the tuning switch circuit includes a first tuning branch, a second tuning branch, a third tuning branch and a fourth tuning branch connected in parallel, one end of the first tuning branch, the second tuning branch, the third tuning branch and the fourth tuning branch is connected to a first node between the fourth capacitor and the fifth capacitor.

[0014] The other end of the first tuning branch is connected between the fifth capacitor and the second feeding source, the second tuning branch includes a fifth inductor, the third tuning branch includes a sixth inductor, and the fourth tuning branch includes a seventh inductor, wherein one end of the fifth inductor, the sixth inductor and the seventh inductor is connected to the first node through a on-off switch, and the other end is grounded.

[0015] In some embodiments, the oscillation circuit includes a parallel LC oscillation circuit or a series LC oscillation circuit.

[0016] In a second aspect, the present disclosure provides an electronic device including the antenna as described in any of the above embodiments.

[0017] In some embodiments, the frame of the electronic device is a rectangular structure, and the radiating branch of the antenna is arranged at a bottom corner of the rectangular structure.

[0018] In some embodiments, the electronic device further includes a bearing part made of metal, which is arranged inside the rectangular structure of the frame, and the bearing part forms a floor of the antenna system.

[0019] In some embodiments, the radiating branch is in an L-shaped structure, the first end of the radiating branch is connected to the bearing part through a rigid structure and grounded, and the second end of the radiating branch is formed as a free end by opening a gap in the frame.

[0020] The antenna of the embodiment of the present disclosure comprises a radiation branch, the first end of the radiation branch is grounded, the second end is a free end, the radiation branch comprises a feeding point and a matching point, the matching point is located between the feeding point and the first end, the matching point is connected to an oscillation circuit grounded, and the feeding point is connected to a feeding circuit, the feeding circuit excites the radiation branch to generate resonance in a low frequency and a medium-high frequency band. In the embodiment of the present disclosure, the oscillation circuit grounded can excite multiple resonance modes of the antenna, thereby widening the bandwidth of the antenna, so that the antenna can cover the low frequency and the medium-high frequency band at the same time, reducing the size of the antenna, and without setting a tuning switch for frequency switching, reducing the cost and design difficulty. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art without creative labor.

[0022] Figure 1 is a schematic diagram of an antenna structure in the related art.

[0023] Figure 2 is a schematic diagram of the structure of an electronic device in some embodiments of the present disclosure.

[0024] Figure 3 is a schematic diagram of the structure of an antenna in some embodiments of the present disclosure.

[0025] Figures 4a to 4c is a current distribution diagram of an antenna in some embodiments of the present disclosure.

[0026] Figure 5 is a schematic diagram of the position of a matching point of an antenna in some embodiments of the present disclosure.

[0027] Figure 6 is a circuit diagram of an oscillation circuit in some embodiments of the present disclosure.

[0028] Figure 7 is a circuit diagram of a feeding circuit in some embodiments of the present disclosure.

[0029] Figure 8 is a schematic diagram of the structure of an antenna in some other embodiments of the present disclosure.

[0030] Figure 9 is a circuit diagram of a feeding circuit and a tuning switch circuit in some embodiments of the present disclosure.

[0031] Figure 10 is a performance curve diagram of an antenna in some embodiments of the present disclosure. DETAILED DESCRIPTION

[0032] The technical solutions of the present disclosure will be described clearly and completely in combination with the drawings. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present disclosure. In addition, the technical features involved in different embodiments of the present disclosure described below can be combined with each other as long as they do not conflict with each other.

[0033] Nowadays, with the development of wireless communication technology, more and more wireless communication antennas are included in electronic devices, such as GPS (Global Positioning System) antennas for realizing satellite positioning, WiFi (wireless fidelity) antennas for realizing wireless local area networks, 4G LTE (Long Term Evolution) antennas and 5G antennas for realizing cellular networks, BT (bluetooth) antennas for realizing Bluetooth connection, and the like. In addition, some electronic devices also include UWB (Ultra Wide Band) antennas, NFC (Near Field Communication) antennas, and the like.

[0034] As can be seen, there are many antennas included in electronic devices, but currently electronic devices are gradually developing towards integration and thinness, and the device space is very compact, which brings challenges to antenna design.

[0035] Taking a smart phone as an example, in order to realize full-band communication with a base station, the phone antenna needs to integrate more and more frequency bands, such as LB low frequency, MB medium frequency, and HB high frequency band, to realize full-band coverage. However, the internal space of the phone is limited, so it is often necessary to do carrier aggregation (CA), that is, to integrate different frequency band signals in the same antenna and use a tuner to switch frequency bands.

[0036] Currently, the antenna of the phone is mainly a frame antenna, that is, the metal frame of the phone is used as a radiator to transmit and receive signals, and a break is opened in the metal frame to realize the separation of different antenna radiators. Taking a low frequency (LB) and medium-high frequency (MHB) integrated antenna as an example, Figure 1 shows an antenna design scheme in the related art.

[0037] Figure 1 only shows the local structure of the bottom of the phone, see Figure 1As shown, the antenna in the related art utilizes a break in the bottom metal frame of the mobile phone as a radiation branch, and then forms an IFA (Inverted-F Antenna) antenna by feeding the radiation branch. Further, in order to broaden the frequency band of the IFA antenna, a tuner needs to be added at the corner of the antenna. The tuner changes the impedance of the antenna system by switching different matching circuits, thereby adjusting the resonant frequency and realizing multi-band switching.

[0038] In the related art, a break in the bottom metal frame of the mobile phone is utilized as a radiation branch, and then an IFA (Inverted-F Antenna) antenna is formed by feeding the radiation branch. Further, in order to broaden the frequency band of the IFA antenna, a tuner needs to be added at the corner of the antenna. The tuner changes the impedance of the antenna system by switching different matching circuits, thereby adjusting the resonant frequency and realizing multi-band switching. Figure 1 The antenna scheme shown can also realize the fusion of low frequency LB and medium-high frequency MHB, but this scheme needs to add a tuner for tuning, needs to design a corresponding circuit layout for the tuner, undoubtedly increasing the design difficulty and cost, and the antenna bandwidth is narrow.

[0039] Based on this, the present disclosure provides an antenna and an electronic device with the antenna, aiming to realize a low-frequency and medium-high-frequency fusion antenna with small size at a lower cost.

[0040] In the present disclosure, the electronic device can be any device type suitable for implementation. It can be understood that in the antenna system of the present disclosure, the antenna radiator is mainly realized by the frame of the electronic device. Therefore, the electronic device can be any device with a metal frame, such as a smartphone, a tablet computer, a wearable device, etc., which is not limited by the present disclosure.

[0041] In some embodiments, the electronic device is taken as a smartphone, for example Figure 2 The structure of the smartphone in some embodiments of the present disclosure is shown. The smartphone includes a frame 100, a screen assembly 200, and a back plate 300. The frame 100 is the main support structure of the smartphone, which is generally made of metal. Various electrical and structural elements of the smartphone can be arranged on the frame 100. For example, one side of the frame 100 is used to mount the screen assembly 200 to form the front of the smartphone, and the other side of the frame 100 is used to mount the back plate 300 to form the back of the smartphone.

[0042] The frame 100 includes a bearing part 120 and a frame 110 formed around the edge of the bearing part 120. After the screen assembly 200 and the back plate 300 are encapsulated, the frame 110 can serve as the appearance side frame of the smartphone. The frame 100 can generally be made of metal such as aluminum alloy or stainless steel, so that the frame 110 can serve as the metal radiator of the antenna system of the smartphone. By opening a break in the frame 110 and connecting the corresponding radio frequency circuit, signal communication of various frequency bands of the smartphone can be realized. The bearing part 120 can serve as the ground plate (GND) of the antenna system. The ground plate is a zero potential element of the electrical system, and the antenna radiator is connected to the ground plate to realize grounding in the antenna system.

[0043] Of course, other various electrical structures can also be included in the smart phone, and the present disclosure Figure 2 For example, a circuit board, various sensors, a battery, and the like are generally provided between the bearing portion 120 of the frame 100 and the back plate 300, which can be understood by those skilled in the art, and thus will not be described in detail.

[0044] First, for the convenience of understanding and description, the following describes the frequency bands included in the low band (LB), the middle-high band (MHB), and the high band (HB) in the field of antennas.

[0045] The frequency range of the low band (LB) is about 700MHz-960MHz, which mainly includes B5, B8, B12, B17, B20, B28 of the LTE (Long Term Evolution) standard, GSM850, GSM900 of the GSM (Global System for Mobile Communications) standard, CDMA0, WCDMA5, WCDMA8 of the CDMA (Code Division Multiple Access) standard, and N28 of the 5G standard.

[0046] The frequency range of the middle-high band (MHB) is about 1710MHz-2690MHz, which mainly includes B1, B3, B4, B7, B34, B38, B39, B40, B41 of the LTE standard, GSM1800, GSM1900 of the GSM standard, WCDMA1, WCDMA2, WCDMA3, WCDMA4 of the CDMA standard, and N1, N3, N7, N38, N41 of the 5G standard.

[0047] The high band (HB) mainly includes N77 (frequency range 3.3GHz-4.2GHz), N78 (frequency range 3.3GHz-3.8GHz), and N79 (frequency range 4.8GHz-4.9GHz) of the 5G standard.

[0048] Second, for the convenience of understanding and description, the following explains some nouns and technical terms appearing in the embodiments of the present disclosure.

[0049] Radiating element / radiating branch: is a device in the antenna for receiving and transmitting electromagnetic wave radiation, and the radiating element / radiating branch is made of metal. In different antenna types and antenna systems, the shape and size of the radiating element / radiating branch are also different. In some cases, the "antenna" in the narrow sense is the radiating element / radiating branch, that is, the radiating element / radiating branch can be directly referred to as the antenna. In the broad sense, the radiating element / radiating branch represents the part of the antenna for receiving and transmitting electromagnetic waves. In addition to the radiating element / radiating branch, the antenna often also includes electrical parts such as feed circuit and matching circuit.

[0050] Feed circuit: is the combination of all circuits for receiving and transmitting radio frequency signals. The feed circuit can include a transceiver and a radio frequency front-end circuit, and in some embodiments, the feed circuit can be a radio frequency chip.

[0051] Feed point: refers to the position on the radiating element / radiating branch that is electrically connected to the feed circuit. In some scenarios, the feed point on the radiating element / radiating branch is also referred to as the "upper frame point", which can be understood as the connection position of the feed circuit and the metal frame.

[0052] Tuning switch circuit: is a circuit for adjusting the radiation characteristics of the antenna. In some embodiments, the tuning switch circuit can be arranged between the feed circuit and the radiating element / radiating branch. In other embodiments, the tuning switch circuit can be arranged between the radiating element / radiating branch and the ground plane. The tuning switch circuit generally includes multiple tuning branches, and can switch between the multiple tuning branches. Each tuning branch is provided with a tuning device, which can be a switch, a capacitor, an inductor, etc.

[0053] Tuning point: refers to the position on the radiating element / radiating branch that is electrically connected to the tuning switch circuit. It can be understood that in the case where the tuning switch circuit is arranged between the feed circuit and the radiating element / radiating branch, the tuning point and the feed point represent the same position.

[0054] Resonance: refers to the resonance frequency generated by the antenna. The resonance frequency can have a frequency range, that is, the frequency range at which the current resonates on the radiating element / radiating branch. The frequency corresponding to the strongest resonance point is the center point of the resonance frequency, also known as the center frequency point. It can be understood that the first resonance in the embodiments of the present disclosure is the radio frequency band generated by the antenna.

[0055] Figure 3 The structure of the antenna in some embodiments of the present disclosure is shown, and the structure and principle of the antenna of the present disclosure are described below. Figure 3 The structure and principle of the antenna of the present disclosure are described.

[0056] Figure 3Only the partial structure of the bottom of the electronic device is shown, and other parts are not shown, but those skilled in the art can understand and fully implement them with reference to the related art without any doubt, and the present disclosure will not be described again.

[0057] In Figure 3 In an example, the gray part is the floor (GND) of the electronic device, and the white strip structure is the metal frame 110 of the electronic device. Figure 2 As shown, the floor can be formed by the bearing part 120 of the electronic device frame 100, and the white strip structure is the metal frame 110 of the electronic device.

[0058] Referring to Figure 3 In the embodiment of the present disclosure, the antenna includes a radiation branch 410, which is formed by opening a slit in the frame 110 of the electronic device. The radiation branch 410 is a strip structure, and its two ends are defined as a first end and a second end, respectively. Figure 3 As shown, the first end a of the radiation branch 410 is rigidly connected to the floor, that is, the radiation branch 410 is grounded at the first end a position, and the second end b of the radiation branch 410 is formed as a free end by opening a slit in the metal frame 110, that is, the second end b is not connected to other structures. Therefore, the effective length of the radiation branch 410 of the antenna is the length between the first end a and the second end b.

[0059] In the embodiment of the present disclosure, the antenna includes a feed circuit K1, and the electrical connection point of the feed circuit K1 on the radiation branch 410 is a feed point s. It can be understood that the first radiation branch 410 grounded at one end and the feed circuit K1 can form an IFA antenna, and the resonance mode of the IFA antenna is 1 / 4 wavelength mode, that is, the effective electrical length of the radiation branch of the IFA antenna is 1 / 4 of the wavelength corresponding to the resonance frequency of the antenna.

[0060] Continuing to refer to Figure 3 , the antenna system further includes an oscillation circuit LC, and the electrical connection point of the oscillation circuit LC on the radiation branch 410 is a matching point t. In the embodiment of the present disclosure, the matching point t is located between the feed point s and the first end a, for example Figure 3 In an example, the feed point s is arranged close to the second end b of the radiation branch 410, and the matching point t is arranged close to the corner position of the radiation branch 410.

[0061] In the embodiment of the present disclosure, the oscillation circuit LC is grounded (GND) at the end, and the function of the oscillation circuit LC is to realize the coexistence of multiple resonance modes through the filtering characteristics of the oscillation circuit, thereby realizing the fusion of low-frequency resonance and high-frequency resonance.

[0062] In the embodiment of the present disclosure, the feeding circuit K1 excites the radiating branch to generate a first resonance, and due to the effect of the oscillation circuit LC, multiple resonance modes of the antenna can be generated, thereby widening the frequency band of the antenna, so that the first resonance can cover the low frequency (LB) and medium-high frequency (MHB) bands.

[0063] Figures 4a to 4c The current schematic diagram of the antenna in the embodiment of the present disclosure in three different resonance modes is shown, in which the black arrows represent the current direction on the radiating branch 410, and the length of the arrow represents the current density. The longer the arrow length, the greater the current density at the position, and vice versa.

[0064] Figure 4a For the current distribution of the low frequency LB resonance mode of the antenna, according to the characteristics of the oscillation circuit, it can be understood that the oscillation circuit LC is equivalent to an open circuit in the low frequency mode, so that for the low frequency band, it is equivalent to an IFA antenna formed by using all the radiating branches between the first end a and the second end b, that is, the effective electrical length of the radiating branch 410 is 1 / 4 of the wavelength corresponding to the low frequency LB band.

[0065] Figure 4b And Figure 4c For the current distribution of the medium-high frequency MHB resonance mode of the antenna, according to the characteristics of the oscillation circuit, it can be understood that the oscillation circuit LC is equivalent to a short circuit in the medium-high frequency mode. First, referring to FIG. 4, for part of the medium-high frequency band, at this time the radiating branch 410 is grounded through the oscillation circuit LC at the position of the matching point t, which is the current zero point, thereby forming a loop current mode from the feeding point s to the matching point t and from the first end a to the matching point t, that is, the antenna is equivalent to a loop antenna in this resonance mode. Then, referring to FIG. 5, for another part of the medium-high frequency band, at this time the radiating branch 410 is equivalent to being grounded at the position of the matching point t, so in this resonance mode, the effective electrical length of the radiating branch is equivalent to the branch length between the matching point t and the second end b, and at this time the resonance mode is a quarter wavelength mode between the matching point t and the second end b. Figure 4b Figure 4c

[0066] According to the above, it can be seen that in the embodiment of the present disclosure, the oscillation circuit grounded can excite multiple resonance modes of the antenna, thereby widening the frequency band of the antenna, so that the antenna can cover the low frequency (LB) band and the medium-high frequency (MHB) band at the same time. For example, in one example, the antenna in the embodiment of the present disclosure can cover the low frequency band B20, B28, etc. on the basis of covering the medium-high frequency band B40, B41, etc.

[0067] ​​In addition, in the embodiments of the present disclosure, the tuning switch is not required to switch the frequency bands, that is, the corresponding circuit layout is not required to be designed for the antenna switch, and only a simple grounding oscillation circuit is required to realize the low-frequency and medium-high-frequency integrated antenna, and the matching point of the oscillation circuit can directly reuse the tuning point in the related technical solutions, without the need to additionally set the upper frame point, thereby reducing the cost and design difficulty.

[0068] In some embodiments, referring to Figure 3 In the antenna of the example of the present disclosure, the radiation branch 410 can be an L-shaped structure, and the L-shaped structure can make full use of the side frame of the electronic device to meet the length of the radiation branch of the low-frequency antenna.

[0069] In some embodiments of the present disclosure, the matching point of the oscillation circuit LC connected to the radiation branch 410 can be arranged close to the bending part of the L-shaped structure. For example Figure 5 In the example, the matching point can be arranged at the positions t1, t2, and t3, and of course, Figure 5 Only as an example of the present disclosure, the matching point can also be located at other positions close to the bending part, and the present disclosure will not be repeated here.

[0070] In some embodiments, the oscillation circuit LC can be a series oscillation circuit or a parallel oscillation circuit. For example Figure 6 As shown in Figure 6 The left side in the middle is a series LC oscillation circuit, Figure 6 The right side in the middle is a parallel LC oscillation circuit, and the series or parallel oscillation circuit can be used in the embodiments of the present disclosure.

[0071] It is worth noting that in the case of using a parallel LC oscillation circuit, the LC oscillation circuit will introduce resonance at low frequencies, affecting the low-frequency efficiency, and therefore the values of the capacitance C and the inductance L need to follow that the self-resonance is not in the low-frequency range of the antenna radiation. In the case of using a series LC oscillation circuit, the low-frequency efficiency can be improved, but the efficiency dip formed by the loop resonance mode of the LC back to the feed point is close to 3 GHz, which will cause the medium-high-frequency B41 band efficiency to be low, so the values of the capacitance C and the inductance L need to follow that the self-resonance is higher than 3 GHz.

[0072] Figure 7 The feeding circuit structure of the antenna in the embodiments of the present disclosure is shown in Figure 3 Figure 7 ​As shown, the feeding circuit includes a first main branch, a first branch and a second branch. The first main branch is a main circuit between the feeding point s and the first feeding source K1, which includes a first inductor L1, a first capacitor C1 and a second inductor L2 connected in series. The first branch includes a second capacitor C2 and a third inductor L3, one end of the second capacitor C2 is connected between the first inductor L1 and the first capacitor C1, the other end is connected to one end of the third inductor L3, and the other end of the third inductor L3 is grounded. The second branch includes a third capacitor C3, one end of the third capacitor C3 is connected between the second inductor L2 and the first feeding source K1, and the other end is grounded.

[0073] It should be noted that, for Figure 7 the values of each capacitor and inductor in the above embodiment, those skilled in the art can obtain them by debugging according to specific scene requirements. In an exemplary embodiment of the present disclosure, the first inductor L1 has a value of 2.5nH, the second inductor L2 has a value of 5nH, the third inductor L3 has a value of 28nH, the first capacitor C1 has a value of 0.8pF, the second capacitor C2 has a value of 0.4pF, and the third capacitor C3 has a value of 1pF.

[0074] It can be understood that in the above embodiment, the antenna system can be compatible with low frequency LB frequency band and medium-high frequency band without tuning switch, for example, the fusion of low frequency bands such as B20, B28 and medium-high frequency bands such as B40, B41 can be realized.

[0075] In other embodiments, in order to further widen the antenna bandwidth, so that it can be compatible with more frequency bands, a tuning switch tuner can be added at the antenna feeding position, and by switching the frequency band through the tuning switch, the fusion of more frequency bands can be realized, which will be described below in combination with Figure 8 .

[0076] Referring to Figure 8 , in the example of the present disclosure, the difference from the foregoing embodiment is that a tuning switch circuit tuner is arranged between the feeding circuit K and the feeding point s, the tuning switch circuit includes a plurality of tuning branches, and a tuning device is arranged on each tuning branch. By switching different tuning branches, different impedances matched by the antenna can be realized, so as to further widen the antenna bandwidth and enable it to cover more low frequency or medium-high frequency bands.

[0077] Figure 9 The circuit structure diagram of the antenna feeding circuit K and the tuning switch circuit tuner is shown in Figure 8 , which will be described below in combination with Figure 9 .

[0078] As Figure 9As shown, in the present example, the feeding circuit K includes a second main branch and a third branch. The second main branch is a main circuit between the feeding point s and the second feeding source K2, which includes the fourth capacitor C4 and the fifth capacitor C5 connected in series. The third branch includes the fourth inductor L4 and the sixth capacitor C6, one end of the fourth inductor L4 is connected between the fourth capacitor C4 and the feeding point s, the other end is connected to one end of the sixth capacitor C6, and the other end of the sixth capacitor C6 is grounded.

[0079] In the example of the present disclosure, the tuning switch circuit includes four tuning branches, namely the first tuning branch ①, the second tuning branch ②, the third tuning branch ③ and the fourth tuning branch ④ as shown in the figure. In the present example, one end of the first tuning branch, the second tuning branch, the third tuning branch and the fourth tuning branch is connected to the first node P between the fourth capacitor C4 and the fifth capacitor C5.

[0080] One end of the first tuning branch is connected to the first node P, and the other end is connected to the fifth capacitor C5 and the second feeding source through the on-off switch, so that in the case that the first tuning branch is turned on, it is equivalent to short-circuiting the fifth capacitor C5. The second tuning branch includes the fifth inductor L5, one end of the fifth inductor L5 is connected to the first node P through the on-off switch, and the other end is grounded. The third tuning branch includes the sixth inductor L6, one end of the sixth inductor L6 is connected to the first node P through the on-off switch, and the other end is grounded. The fourth tuning branch includes the seventh inductor L7, one end of the seventh inductor L7 is connected to the first node P through the on-off switch, and the other end is grounded.

[0081] In the embodiment of the present disclosure, the on-off of each tuning branch of the tuning switch circuit can be controlled by the on-off switch. When it is needed to switch to a certain tuning branch, only the on-off switch of the tuning branch needs to be closed, and the on-off switches of other tuning branches need to be opened.

[0082] It is worth noting that, for Figure 9 The values of each capacitor and inductor in the above-mentioned example can be adjusted according to the specific scene requirements by those skilled in the art. In an exemplary embodiment of the present disclosure, the fourth capacitor C4 has a value of 2.5 pF, the fifth capacitor C5 has a value of 1 pF, the sixth capacitor C6 has a value of 0.6 pF, the fourth inductor L4 has a value of 30 nH, the fifth inductor L5 has a value of 2.9 nH, the sixth inductor L6 has a value of 1.9 nH, and the seventh inductor L7 has a value of 4.5 nH.

[0083] As can be seen from the above, in the embodiment of the present disclosure, different tuning branches are switched by using the tuning switch circuit, which can realize matching different impedances of the antenna, thereby further widening the bandwidth of the antenna and enabling it to cover more low-frequency or medium-high frequency bands.

[0084] In some embodiments, the present disclosure provides an electronic device, which can be any of the aforementioned device types, and will not be repeated here. The electronic device of the present disclosure includes the antenna of any of the aforementioned embodiments, for example, the electronic device is a smart phone, and the antenna is combined with Figure 2 As shown in FIG. 10, in the antenna of the embodiment of the present disclosure, the radiating stub 410 can be implemented by the metal frame 110 of the electronic device.

[0085] As shown in FIG. 11, the radiating stub 410 can be arranged at the bottom of the phone and located at the corner of the bottom, so that the side frame can be fully utilized, and the design difficulty of the low-frequency antenna is reduced. Figure 3 As shown in FIG. 11, the radiating stub 410 can be arranged at the bottom of the phone and located at the corner of the bottom, so that the side frame can be fully utilized, and the design difficulty of the low-frequency antenna is reduced.

[0086] Figure 10 FIG. 12 shows a performance curve comparison diagram of the antenna of the embodiment of the present disclosure compared with the conventional IFA antenna, in which the red line is the performance curve of the antenna of the embodiment of the present disclosure, and the green line is the performance curve of the conventional IFA antenna. Through Figure 10 As can be seen from the comparison, the antenna of the embodiment of the present disclosure effectively improves the performance of the low-frequency band while ensuring that the performance of the medium and high-frequency bands is almost unchanged, which proves that the antenna of the embodiment of the present disclosure can effectively compatible with the low-frequency band and the medium and high-frequency band.

[0087] As can be seen from the above, in the embodiment of the present disclosure, the grounded oscillation circuit can excite multiple resonance modes of the antenna, thereby widening the bandwidth of the antenna, so that the antenna can cover the low-frequency and medium and high-frequency bands at the same time, and the size of the antenna is reduced. In addition, the multi-band fusion antenna can be implemented without setting the tuning switch, thereby reducing the cost and design difficulty. Moreover, in the case of adding the tuning switch, different tuning branches can be switched by the tuning switch circuit, so that the antenna can be matched with different impedances, thereby further widening the bandwidth of the antenna and enabling it to cover more low-frequency or medium and high-frequency bands.

[0088] Obviously, the above embodiments are only examples for the purpose of clear illustration, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and impossible to exhaust all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present disclosure.

Claims

1. An antenna, characterized in that, Includes a radiating branch formed by the frame of the electronic device, wherein a first end of the radiating branch is grounded and a second end is a free end; The radiating stub includes a feed point and a matching point. The matching point is located between the feed point and the first end. The matching point is connected to an oscillation circuit, which is grounded. The feed point is connected to a feed circuit, which excites the radiating stub to generate a first resonance. The first resonance includes a low-frequency band and a mid-to-high-frequency band.

2. The antenna according to claim 1, characterized in that, The radial branch has an L-shaped structure, and the matching point is located near the bend of the L-shaped structure.

3. The antenna according to claim 1, characterized in that, The power supply circuit includes a first main circuit, a first branch circuit, and a second branch circuit. The first main circuit is connected in series with a first inductor, a first capacitor, a second inductor, and a first feed source. The first branch includes a second capacitor and a third inductor. One end of the second capacitor is connected between the first inductor and the first capacitor, and the other end is connected to the third inductor. The third inductor is grounded. The second branch includes a third capacitor, one end of which is connected between the second inductor and the first feed source, and the other end is grounded.

4. The antenna according to claim 1, characterized in that, It also includes a tuning switch circuit connected between the power supply circuit and the power supply point, the tuning switch circuit being configured to adjust the resonant frequency of the first resonance by switching different tuning branches.

5. The antenna according to claim 4, characterized in that, The power supply circuit includes a second main circuit and a third branch circuit. A fourth capacitor, a fifth capacitor, and a second feed source are connected in series on the second main circuit. The third branch includes a fourth inductor and a sixth capacitor. One end of the fourth inductor is connected between the fourth capacitor and the feed point, and the other end is connected to one end of the sixth capacitor. The other end of the sixth capacitor is grounded.

6. The antenna according to claim 5, characterized in that, The tuning switch circuit includes a first tuning branch, a second tuning branch, a third tuning branch, and a fourth tuning branch connected in parallel. One end of each of the first tuning branch, the second tuning branch, the third tuning branch, and the fourth tuning branch is connected to a first node between the fourth capacitor and the fifth capacitor. The other end of the first tuning branch is connected between the fifth capacitor and the second feed source; the second tuning branch includes a fifth inductor, the third tuning branch includes a sixth inductor, and the fourth tuning branch includes a seventh inductor, wherein one end of the fifth inductor, the sixth inductor, and the seventh inductor is connected to the first node through an on / off switch, and the other end is grounded.

7. The antenna according to any one of claims 1 to 6, characterized in that, The oscillation circuit includes a parallel LC oscillation circuit or a series LC oscillation circuit.

8. An electronic device, characterized in that, Including the antenna according to any one of claims 1 to 7.

9. The electronic device according to claim 8, characterized in that, The frame of the electronic device is a rectangular structure, and the radiating stub of the antenna is located at the bottom corner of the rectangular structure.

10. The electronic device according to claim 9, characterized in that, It also includes a metal support portion, which is located inside the rectangular structure of the frame and forms the floor of the antenna system; The radial branch has an L-shaped structure. The first end of the radial branch is connected to the bearing part and grounded through a rigid structure, and the second end is formed as a free end by opening a slit in the frame.

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