Antenna module and electronic device

Abstract

The present disclosure provides an antenna module and an electronic apparatus that do not deteriorate radiation efficiency even when a plurality of antennas are disposed in a narrow area. An antenna module according to the present disclosure includes a first antenna having a first resonant frequency, a second antenna having a second resonant frequency, and a first band elimination filter connected to the second antenna. The first antenna includes a first feed circuit and a first radiating element connected to the first feed circuit. The second antenna comprises a second feed circuit and a second radiating element connected to the second feed circuit. The first band elimination filter cuts off the first resonant frequency, and the first radiating element and the second radiating element are coupled by means of at least one of an electric field and a magnetic field, whereby a first path passing through the second radiating element from the ground via the first band elimination filter operates as a non-feed antenna having a third resonant frequency.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an antenna module and an electronic device, and relates to an antenna module and an electronic device that do not degrade radiation efficiency even when multiple antennas are arranged in a narrow area. BACKGROUND

[0002] An antenna module provided with multiple antennas to enable the use of a wide frequency band is disclosed in Japanese Patent No. 7176667 (Patent Literature 1). In this antenna module, a series resonance circuit is provided in one of the multiple antennas, and is substantially set to a ground state, whereby the radiation efficiency of the other antenna is maintained high without being disturbed by the one antenna.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent No. 7176667 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] However, in the antenna module disclosed in Japanese Patent No. 7176667 (Patent Literature 1), while it can not be disturbed in a high frequency region, the one antenna can be regarded as GND from the viewpoint of the other antenna, and becomes a state in which electromagnetic waves radiated from the other antenna are absorbed by the one antenna, and thus there is a risk that the radiation efficiency of the other antenna is degraded.

[0008] The present disclosure was made to solve such a problem, and aims to provide an antenna module and an electronic device that do not degrade radiation efficiency even when multiple antennas are arranged in a narrow area.

[0009] SOLUTION TO PROBLEM

[0010] The antenna module according to the present disclosure includes a first antenna having a first resonance frequency, a second antenna having a second resonance frequency, and a first band elimination filter connected to the second antenna. The first antenna includes a first feeding circuit and a first radiating element connected to the first feeding circuit. The second antenna includes a second feeding circuit and a second radiating element connected to the second feeding circuit. The first band elimination filter cuts off the first resonance frequency, and the first radiating element and the second radiating element are coupled by at least one of an electric field and a magnetic field, whereby a first path from the ground via the second radiating element through the first band elimination filter acts as an un-fed antenna having a third resonance frequency.

[0011] The electronic device according to this disclosure includes the antenna module described above and a substrate for mounting the antenna module.

[0012] The effects of the invention

[0013] In the antenna module based on this disclosure, a first band-stop filter cuts off a first resonant frequency, and a first radiating element and a second radiating element are coupled through at least one of an electric field and a magnetic field. Thus, a first path from ground through the first band-stop filter through the second radiating element operates as an unfed antenna with a third resonant frequency, so that even when multiple antennas are configured in a narrow area, the radiation efficiency is not degraded. Attached Figure Description

[0014] Figure 1 This is a diagram showing the structure of the antenna module in Embodiment 1.

[0015] Figure 2A This is a diagram showing the circuit diagram of the band-stop filter in the antenna module of Embodiment 1.

[0016] Figure 2B This is a diagram showing the circuit diagram of the band-stop filter in the modified example.

[0017] Figure 2C This is a diagram showing the circuit diagram of the band-stop filter in the antenna module of another variation.

[0018] Figure 3 This is a diagram illustrating an example of the characteristics of a band-stop filter.

[0019] Figure 4 This is a diagram showing the structure of an antenna module with a reactor installed in the first path.

[0020] Figure 5 This is a graph illustrating an example of the radiation efficiency of the first antenna in Embodiment 1.

[0021] Figure 6 This is a graph illustrating an example of the radiation efficiency of the second antenna in Embodiment 1.

[0022] Figure 7 This is a diagram showing the structure of the electronic device in Embodiment 1.

[0023] Figure 8 This is a diagram showing the structure of the antenna module in a variation of Embodiment 1.

[0024] Figure 9 This is a diagram showing the structure of a modified example of a band-stop filter.

[0025] Figure 10 This is a diagram showing the structure of the antenna module in Embodiment 2. Detailed Implementation

[0026] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings. Furthermore, the same or equivalent parts in the drawings will be labeled with the same reference numerals, and their descriptions will not be repeated. Additionally, the radiation efficiency in this disclosure is used to represent the ratio of the output radiated from the antenna to the power supplied from the feed circuit. That is, the efficiency relative to the power supplied from the feed circuit, including circuit losses and losses due to mismatch, is indicated by a smaller negative value at the top of the graph, signifying a better radiation efficiency.

[0027] [Implementation Method 1]

[0028] Figure 1 This is a diagram illustrating the structure of antenna module 1 in Embodiment 1. Antenna module 1 includes a first antenna 100, a second antenna 200, and a band-stop filter 10 (first band-stop filter) connected to the second antenna 200. The first antenna 100 includes a feed circuit RF1 (first feed circuit) and a first radiating element 101. The second antenna 200 includes a feed circuit RF2 (second feed circuit) and a second radiating element 201.

[0029] Antenna module 1 is, for example, mounted on portable terminals such as mobile phones, smartphones or tablets, communication devices such as smartwatches with communication functions, and personal computers. The first antenna 100 is, for example, a monopole antenna. The second antenna 200 is, for example, a monopole antenna.

[0030] The power supply circuit RF1 supplies a high-frequency signal in the f1 band (first resonant frequency) to the first radiating element 101. The first radiating element 101 can radiate the high-frequency signal in the f1 band supplied by the power supply circuit RF1 as a radio wave into the air. The f1 band is, for example, a band including n77 (3.3 GHz - 4.2 GHz).

[0031] The power supply circuit RF2 supplies a high-frequency signal in the f2 band (second resonant frequency) to the second radiating element 201. The second radiating element 201 can radiate the high-frequency signal in the f2 band supplied by the power supply circuit RF2 as a radio wave into the air. The f2 band is, for example, a band that includes the 5GHz band of WiFi (registered trademark).

[0032] A band-stop filter 10 is connected between the second radiating element 201 and ground. The band-stop filter 10 cuts off or attenuates high-frequency signals in the f1 frequency band. The band-stop filter 10 is configured to allow high-frequency signals in the f2 frequency band to pass through.

[0033] As described below, the first radiating element 101 and the second radiating element 201 are mounted on the same substrate. While the first radiating element 101 and the second radiating element 201 are disposed on the same substrate, they can also be disposed on different substrates as long as they are within the same antenna module 1. By disposing them on the same substrate in this way, the distance between the antennas remains constant, thus ensuring that the coupling state between the first radiating element 101 and the second radiating element 201 remains constant.

[0034] The first radiating element 101 and the second radiating element 201 are coupled by at least one of an electric field and a magnetic field. A band-stop filter 10 is disposed between the second radiating element 201 and ground. Thus, the path from ground through the band-stop filter 10 and through the second radiating element 201 functions as an unfed antenna in the f3 band (third resonant frequency). Furthermore, the f3 band (third resonant frequency) can also be the same communication band as the f1 band (first resonant frequency).

[0035] Figure 2A This is a circuit diagram showing the band-stop filter 10 in the antenna module 1 of Embodiment 1. The band-stop filter 10 includes a first filter circuit connected in series between ground and the second radiating element 201 and resonating therein, and a second filter circuit connected in parallel with the second radiating element 201 and resonating therein. In the second filter circuit, a second capacitor C2 and a second coil L2 are connected in parallel between the second radiating element 201 and the feed circuit RF2. In the first filter circuit, a first capacitor C1 and a first coil L1 are connected in series between one end of the second filter circuit and ground. In the band-stop filter 10, the second filter circuit is connected at a position closer to the feed circuit RF2 than the first filter circuit.

[0036] The band-stop filter 10 is configured to cut off or attenuate the high-frequency signal in the f1 frequency band and allow the high-frequency signal in the f2 frequency band to pass through. Figure 3 This is a diagram illustrating an example of the characteristics of the band-stop filter 10. Figure 3 The horizontal axis represents frequency [GHz], the vertical axis to the right represents reflection loss (S11) [dB], and the vertical axis to the left represents insertion loss (S21) [dB]. The solid line represents reflection loss, and the dashed line represents insertion loss. The band-stop filter 10 has the characteristic that the reflection loss (S11) is high and the insertion loss (S21) is low in the frequency range of 3.3GHz-4.2GHz.

[0037] Antenna module 1 maintains high radiation efficiency of the first antenna 100 by cutting off or attenuating high-frequency signals in the f1 band of the second antenna 200 through a band-stop filter 10 that cuts off or attenuates the high-frequency signals in the f1 band. Furthermore, in antenna module 1, the radiation from ground through the band-stop filter 10 to the second radiating element 201... Figure 2A The first path T1 shown operates as an unfed antenna with a frequency band of f3. In antenna module 1, by operating the first path T1 as an unfed antenna with a frequency band of f3, the electromagnetic waves radiated from the first antenna 100 are not absorbed by the second antenna 200, thus suppressing the degradation of the radiation efficiency of the first antenna 100. By using the band-stop filter 10 in this way, radiation efficiency can be maintained even when the two antennas are arranged close together.

[0038] To enable the first path T1 to operate as an unfed antenna with a frequency band of f3, for example, the first path T1 can resonate at 1 / 4 wavelength of the f3 frequency band. If the first path T1 includes a first filter circuit (first capacitor C1 and first coil L1) but does not resonate at 1 / 4 wavelength of the f3 frequency band, adjustment can also be made by incorporating at least one of the components: a reactor and a capacitor.

[0039] Furthermore, a modified example of the band-stop filter 10 will be described. Figure 2B This is a diagram showing the circuit diagram of the band-stop filter in the modified example. Figure 2B The band-stop filter 10 shown includes: a first filter circuit connected between ground and the second radiating element 201, which is formed by a series resonant circuit and an inductor circuit connected in parallel; and a second filter circuit connected to the second radiating element 201, which resonates in parallel. In the first filter circuit, a first capacitor C1 and a first coil L1 are connected in series between one end of the second filter circuit and ground, forming a series resonant circuit that is connected in parallel with an inductor circuit including a third coil L3.

[0040] Through such Figure 2B By connecting the series resonant circuit and the inductor circuit in parallel, as shown in the first filter circuit, the pass characteristics of each resonant frequency from the first to the third resonant frequency can be better set. In particular, Figure 2B The first filter circuit shown can maintain the transmission characteristics of the third resonant frequency and reduce the signal of the second resonant frequency flowing to ground, thereby improving the radiation efficiency of the second resonant frequency.

[0041] Furthermore, another variation of the band-stop filter 10 will be described. Figure 2C This is a diagram showing the circuit diagram of a band-stop filter in another variation. Figure 2CThe band-stop filter 10 shown includes: a first filter circuit connected between ground and the second radiating element 201, which is formed by a series resonant circuit and a capacitor circuit connected in parallel; and a second filter circuit connected to the second radiating element 201, which resonates in parallel. In the first filter circuit, a first capacitor C1 and a first coil L1 are connected in series between one end of the second filter circuit and ground, forming a series resonant circuit connected in parallel with a capacitor circuit including a third capacitor C3.

[0042] Through such Figure 2C By connecting the series resonant circuit and the capacitor circuit in parallel as shown in the first filter circuit, the pass characteristics of each resonant frequency from the first resonant frequency to the third resonant frequency can be better set.

[0043] Figure 4 This diagram illustrates the structure of an antenna module 1a with an inductor installed in the first path T1. The antenna module 1a includes a coil La to cause the first path T1 of the band-stop filter 10a, located in the first antenna 100a, to resonate at 1 / 4 wavelength of the f3 frequency band. The coil La is positioned between the first filter circuit and the second radiating element 201. The band-stop filter 10a only needs to include at least one of an inductor and a capacitor to cause the first path T1 to resonate at 1 / 4 wavelength of the f3 frequency band.

[0044] Figure 5 This is a diagram illustrating an example of the radiation efficiency of the first antenna 100 in Embodiment 1. Figure 6 This is a graph illustrating an example of the radiation efficiency of the second antenna 200 in Embodiment 1. Figure 5 , 6 In the graph, the horizontal axis represents frequency [GHz], and the vertical axis represents radiative efficiency [dB]. Figure 5 , 6 In the diagram, solid waveforms A and C represent the radiation efficiency of the first antenna 100 and the second antenna 200 in Embodiment 1, while dashed waveforms B and D represent the radiation efficiency of the first antenna 100 and the second antenna 200 without the band-stop filter 10.

[0045] like Figure 5 As shown, in the frequency band n77 (3.3GHz-4.2GHz), which includes the high-frequency signal supplied by the feed circuit RF1, the radiation efficiency of waveform A (solid line) is higher than that of waveform B (dashed line). Therefore, it can be seen that antenna module 1 improves the radiation efficiency of the first antenna 100 by setting the band-stop filter 10.

[0046] In addition, such as Figure 6As shown, in the 5GHz band of the f2 frequency band supplied by the high-frequency signal from the feed circuit RF2, the radiation efficiency of waveform C (solid line) and waveform D (dashed line) are not degraded. On the other hand, it can be seen that the second antenna 200 of antenna module 1 cuts off the band containing n77 (3.3GHz-4.2GHz) by setting the band-stop filter 10.

[0047] Next, an electronic device with antenna module 1 mounted on a substrate will be described. Figure 7 This is a diagram showing the structure of the electronic device 5 in Embodiment 1. Figure 7 The illustrated electronic device 5 is, for example, a portable terminal capable of communication in a frequency band including n77 (3.3GHz-4.2GHz) and a 5GHz frequency band. Therefore, the electronic device 5 includes a first antenna 100 activated in the n77 frequency band and a second antenna 200 activated in the 5GHz frequency band. The electronic device 5 has an antenna module 1 mounted on a substrate 300. Furthermore, the electronic device 5 may be, for example, a portable telephone, a smartphone, or a tablet computer.

[0048] In antenna module 1, a first radiating element 101 and a second radiating element 201 are patterned in a narrow non-grounded region 302 of substrate 300. Feed circuits RF1 and RF2, and a band-stop filter 10 are mounted in the circuit region 301 of substrate 300. The first radiating element 101 is electrically connected to the feed circuit RF1 via wiring not shown. Circuit region 301 is also a grounded region containing a ground layer within the substrate; however, for lower frequency antenna modules, circuit region 301 may also be located in a non-grounded region. The second radiating element 201 is electrically connected to the band-stop filter 10 and the feed circuit RF1 via wiring not shown.

[0049] like Figure 7 As shown, the first radiating element 101 is composed of a linear conductor pattern extending to the left in the figure, and the second radiating element 201 is composed of a linear conductor pattern extending to the left in the figure, located inside the substrate 300 compared to the first radiating element 101. Both the first radiating element 101 and the second radiating element 201 function as monopole antennas. However, the type of antenna is not limited to monopole; it can also be a dipole, inverted-F, or other antennas. Furthermore, the frequency band of the f3 band can be the same as the frequency band of the f1 band, or it can be another frequency band. If the frequency band of the f3 band is the same as the frequency band of the f1 band, the radiation efficiency of the first antenna 100 can be improved. When the frequency band of the f3 band is a different frequency band from the frequency band of the f1 band, adding a resonance in a frequency band different from the frequency band of the f1 band to the first antenna 100 can achieve broadband.

[0050] (Modified Example)

[0051] Band-stop filter 10, as in Figure 2A As explained, the second filter circuit is connected closer to the feed circuit RF2 side than the first filter circuit. However, the band-stop filter is not limited to this, and the first filter circuit can also be connected closer to the feed circuit RF2 side than the second filter circuit. Figure 8 This is a diagram showing the structure of antenna module 1b in a variation of embodiment 1. Furthermore, in Figure 8 In the antenna module 1b shown, for the antenna module 1b, the antenna module 1b is used for the antenna module 1 Figure 2A The antenna module 1 shown has the same structure and is labeled with the same reference numerals, and will not be described in detail again.

[0052] Antenna module 1b includes a first antenna 100, a second antenna 200b, and a band-stop filter 10b (first band-stop filter) connected to the second antenna 200. The first antenna 100 includes a feed circuit RF1 (first feed circuit) and a first radiating element 101. The second antenna 200b includes a feed circuit RF2 (second feed circuit) and a second radiating element 201.

[0053] A band-stop filter 10b is connected between the second radiating element 201 and ground. The band-stop filter 10b cuts off or attenuates high-frequency signals in the f1 frequency band. The band-stop filter 10b is configured to allow high-frequency signals in the f2 frequency band to pass through.

[0054] like Figure 8 As shown, the band-stop filter 10b includes a first filter circuit connected in series between ground and the second radiating element 201 and resonating therein, and a second filter circuit connected in parallel with the second radiating element 201 and resonating therein. In the first filter circuit, a first capacitor C1 and a first coil L1 are connected in series between the second radiating element 201 and ground. In the second filter circuit, a second capacitor C2 and a second coil L2 are connected in parallel between the second radiating element 201 and the feed circuit RF2. The first filter circuit of the band-stop filter 10b is connected at a position closer to the feed circuit RF2 than the second filter circuit.

[0055] In antenna module 1b, the signal flows from ground through band-stop filter 10 and through second radiating element 201. Figure 3 The first path T1a shown operates as an unfed antenna with a frequency band of f3. In antenna module 1, by operating as an unfed antenna with a frequency band of f3 through the first path T1a, the electromagnetic waves radiated from the first antenna 100 are not absorbed by the second antenna 200, thus suppressing the degradation of the radiation efficiency of the first antenna 100.

[0056] Furthermore, in the band-stop filter 10b, the first filter circuit is connected closer to the feed circuit RF2 than the second filter circuit, thus the second filter circuit is included in the first path T1a. In the first path T1a, resonance occurs at 1 / 4 wavelength of the frequency band f3 within the area including the second filter circuit. Even if the first path T1a includes the first filter circuit (first capacitor C1 and first coil L1) and the second filter circuit (second capacitor C2 and second coil L2), but does not resonate at 1 / 4 wavelength of the frequency band f3, adjustment can be made by providing at least one element from the inductor and capacitor.

[0057] Furthermore, it is explained that the circuit structure of a band-stop filter consists of a two-stage filter circuit including a first filter circuit and a second filter circuit, but it can also be composed of a multi-stage filter circuit. Figure 9 This is a diagram showing the structure of a modified example of a band-stop filter. Figure 9 The band-stop filter 10c shown in (a) is a three-stage filter circuit consisting of a third filter circuit that resonates in parallel, added in addition to the first and second filter circuits. In the third filter circuit, the third capacitor C3 and the third coil L3 are connected in parallel with respect to the second radiating element 201.

[0058] Figure 9 The band-stop filter 10d shown in (b) is composed of a three-stage filter circuit, which adds a fourth filter circuit that generates series resonance in addition to the first and second filter circuits. In the fourth filter circuit, the fourth capacitor C4 and the fourth coil L4 are connected in series between the second radiating element 201 and ground. The band-stop filter provided on the second antenna 200 can be any structure that includes at least one of a filter circuit that generates series resonance and a filter circuit that generates parallel resonance, in addition to the first and second filter circuits.

[0059] [Implementation Method 2]

[0060] Figure 10 This is a diagram showing the structure of antenna module 2 in embodiment 2. Furthermore, in Figure 10 In the antenna module 2 shown, for... Figure 2A The antenna module 1 shown has the same structure and is labeled with the same reference numerals, and will not be described in detail again.

[0061] Antenna module 2 includes a first antenna 100a, a second antenna 200, a band-stop filter 10 (first band-stop filter) connected to the second antenna 200, and a band-stop filter 20 (second band-stop filter) connected to the first antenna 100a. The first antenna 100a includes a feed circuit RF1 (first feed circuit) and a first radiating element 101. The second antenna 200 includes a feed circuit RF2 (second feed circuit) and a second radiating element 201.

[0062] A band-stop filter 20 is connected to the first radiating element 101 and is also grounded. The band-stop filter 20 allows high-frequency signals in the f1 frequency band to pass through. The band-stop filter 20 is configured to cut off or attenuate high-frequency signals in the f2 frequency band.

[0063] A band-stop filter 10 is connected between the second radiating element 201 and ground. The band-stop filter 10 cuts off or attenuates high-frequency signals in the f1 frequency band. The band-stop filter 10 is configured to allow high-frequency signals in the f2 frequency band to pass through.

[0064] The band-stop filter 20 includes a fifth filter circuit connected in series between ground and the first radiating element 101 and resonating with each other, and a sixth filter circuit connected in parallel with the first radiating element 101 and resonating with each other. In the fifth filter circuit, capacitor CA and coil LA are connected in series between the first radiating element 101 and ground. In the sixth filter circuit, capacitor CB and coil LB are connected in parallel between the first radiating element 101 and the feed circuit RF1. In the band-stop filter 20, the sixth filter circuit is located on the feed circuit RF1 side, and the fifth filter circuit is located on the first radiating element 101 side.

[0065] In antenna module 2, the first antenna 100a operates as an unfed antenna with a frequency band (fourth resonant frequency) via a second path T2 from ground through a band-stop filter 20 and the first radiating element 101. In antenna module 2, operating as an unfed antenna with a frequency band of f4 via the second path T2 prevents the absorption of electromagnetic waves radiated from the second antenna 200 by the first antenna 100, thus suppressing the degradation of the radiation efficiency of the second antenna 200.

[0066] To enable the second path T2 to operate as an unfed antenna with a frequency band of f4, for example, the second path T2 can resonate at 1 / 4 wavelength of the f4 frequency band. If the second path T2 includes a fifth filter circuit (capacitor CA and coil LA) but does not resonate at 1 / 4 wavelength of the f4 frequency band, this can also be adjusted by incorporating at least one of the components: a reactor and a capacitor.

[0067] The circuit structure of the band-stop filter 20 can also be adopted.Figure 8 The band-stop filter 10b shown Figure 9 The band-stop filter 10c shown in (a) Figure 9 The circuit structure of the band-stop filter 10d is shown in (b). Furthermore, the frequency band of the f4 band can be the same as the frequency band of the f2 band, or it can be another frequency band. When the frequency band of the f4 band is the same as the frequency band of the f2 band, adding the first antenna 100a to the second antenna 200 improves radiation efficiency. When the frequency band of the f4 band is different from the frequency band of the f2 band, adding a resonance to the second antenna 200 in a frequency band different from the frequency band of the f2 band enables broadband operation.

[0068] [Other variations]

[0069] Furthermore, in each embodiment, the case where the antenna device is a monopole antenna has been described, but the antenna device may also be other antennas such as an inverted F-type antenna.

[0070] [Way]

[0071] (1) The antenna module involved in this disclosure has the following features:

[0072] The first antenna has a first resonant frequency;

[0073] A second antenna, having a second resonant frequency; and

[0074] The first band-stop filter is connected to the second antenna.

[0075] The first antenna includes a first feeding circuit and a first radiating element connected to the first feeding circuit.

[0076] The second antenna includes a second feed circuit and a second radiating element connected to the second feed circuit.

[0077] The first band-stop filter cuts off the first resonant frequency.

[0078] The first radiating element and the second radiating element are coupled through at least one of an electric field and a magnetic field, thereby operating as an unfed antenna with a third resonant frequency via a first path from ground through a first band-stop filter through the second radiating element.

[0079] (2) According to the antenna module described in (1), wherein,

[0080] The first path resonates at 1 / 4 wavelength of the third resonant frequency, thus functioning as an unfed antenna with the third resonant frequency.

[0081] (3) The antenna module according to (2), wherein,

[0082] The first path includes at least one of a reactor and a capacitor to achieve resonance at 1 / 4 wavelength of the third resonant frequency.

[0083] (4) The antenna module according to any one of (1) to (3), wherein,

[0084] The third resonant frequency is the same communication frequency band as the first resonant frequency.

[0085] (5) The antenna module according to any one of (1) to (4), wherein,

[0086] The first band-stop filter includes:

[0087] The first filter circuit, connected between ground and the second radiating element, exhibits series resonance; and

[0088] The second filter circuit is connected between the second radiating element and the feed circuit, and it achieves parallel resonance.

[0089] (6) The antenna module according to any one of (1) to (4), wherein,

[0090] The first band-stop filter includes:

[0091] The first filter circuit, connected between ground and the second radiating element, is composed of a series resonant circuit and an inductor circuit connected in parallel; and

[0092] The second filter circuit is connected between the second radiating element and the feed circuit, and it achieves parallel resonance.

[0093] (7) The antenna module according to any one of (1) to (4), wherein,

[0094] The first band-stop filter includes:

[0095] The first filter circuit, connected between ground and the second radiating element, is composed of a series resonant circuit and a capacitor circuit connected in parallel; and

[0096] The second filter circuit is connected between the second radiating element and the feed circuit, and it achieves parallel resonance.

[0097] (8) The antenna module according to any one of (5) to (7), wherein,

[0098] In the first band-stop filter, the second filter circuit is connected at a position closer to the second feed circuit than the first filter circuit.

[0099] (9) The antenna module according to any one of (5) to (7), wherein,

[0100] In the first band-stop filter, the first filter circuit is connected to a position closer to the second feed circuit than the second filter circuit.

[0101] (10) The antenna module according to any one of (5) to (9), wherein,

[0102] The first band-stop filter includes, in addition to the first filter circuit and the second filter circuit, at least one of a filter circuit that exhibits series resonance and a filter circuit that exhibits parallel resonance.

[0103] (11) The antenna module according to any one of (1) to (10), wherein,

[0104] It also features a second band-stop filter, which is connected to the first antenna.

[0105] The second band-stop filter cuts off the fourth resonant frequency.

[0106] (12) The antenna module according to (11), wherein,

[0107] The first radiating element and the second radiating element are coupled through at least one of the electric field and the magnetic field, thereby resonating from the ground through the second path of the first radiating element at 1 / 4 wavelength of the fourth resonant frequency, and thus operating as an unfed antenna with the fourth resonant frequency.

[0108] (13) The antenna module according to (11) or (12), wherein,

[0109] The fourth resonant frequency is the same as the second resonant frequency in the communication frequency band.

[0110] (14) The electronic equipment involved in this disclosure has the following features:

[0111] The antenna module according to any one of (1) to (13); and

[0112] The substrate is used to mount the antenna module.

[0113] The embodiments disclosed herein should be considered illustrative rather than restrictive in all respects. The scope of the invention is shown not by the description of the above embodiments but by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0114] Explanation of reference numerals in the attached figures

[0115] 1, 2: Antenna modules; 10, 20: Band-stop filters; 100, 100a: First antenna; 200, 200a, 200b: Second antenna; 101, 201: Radiating elements; 300: Substrate; RF1, RF2: Feed circuits.

Claims

1. An antenna module, comprising: The first antenna has a first resonant frequency; A second antenna, having a second resonant frequency; and A first band-stop filter is connected to the second antenna. in, The first antenna includes a first feeding circuit and a first radiating element connected to the first feeding circuit. The second antenna includes a second feed circuit and a second radiating element connected to the second feed circuit. The first band-stop filter cuts off the first resonant frequency. The first radiating element and the second radiating element are coupled through at least one of an electric field and a magnetic field, thereby operating as an unfed antenna with a third resonant frequency via a first path from ground through the first band-stop filter through the second radiating element.

2. The antenna module according to claim 1, wherein, The first path resonates at 1 / 4 wavelength of the third resonant frequency to function as an unfed antenna with the third resonant frequency.

3. The antenna module according to claim 2, wherein, The first path includes at least one of a reactor and a capacitor to achieve resonance at 1 / 4 wavelength of the third resonant frequency.

4. The antenna module according to any one of claims 1 to 3, wherein, The third resonant frequency is the same communication frequency band as the first resonant frequency.

5. The antenna module according to any one of claims 1 to 4, wherein, The first band-stop filter includes: A first filter circuit, connected between the ground and the second radiating element, exhibits series resonance; and The second filter circuit is connected between the second radiating element and the second feed circuit, and it resonates in parallel.

6. The antenna module according to any one of claims 1 to 4, wherein, The first band-stop filter includes: The first filter circuit, connected between the ground and the second radiating element, is composed of a series resonant circuit and an inductor circuit connected in parallel; and The second filter circuit is connected between the second radiating element and the second feed circuit, and it resonates in parallel.

7. The antenna module according to any one of claims 1 to 4, wherein, The first band-stop filter includes: The first filter circuit, connected between the ground and the second radiating element, is composed of a series resonant circuit and a capacitor circuit connected in parallel; and The second filter circuit is connected between the second radiating element and the second feed circuit, and it resonates in parallel.

8. The antenna module according to any one of claims 5 to 7, wherein, In the first band-stop filter, the second filter circuit is connected at a position closer to the second feed circuit than the first filter circuit.

9. The antenna module according to any one of claims 5 to 7, wherein, In the first band-stop filter, the first filter circuit is connected at a position closer to the second feed circuit than the second filter circuit.

10. The antenna module according to any one of claims 5 to 9, wherein, In addition to the first filter circuit and the second filter circuit, the first band-stop filter also includes at least one of a filter circuit that exhibits series resonance and a filter circuit that exhibits parallel resonance.

11. The antenna module according to any one of claims 1 to 10, wherein, It also includes a second band-stop filter, which is connected to the first antenna. The second band-stop filter cuts off the fourth resonant frequency.

12. The antenna module according to claim 11, wherein, The first radiating element and the second radiating element are coupled through at least one of an electric field and a magnetic field, thereby resonating from ground via the second band-stop filter through the second path of the first radiating element at 1 / 4 wavelength of the fourth resonant frequency, and thus operating as an unfed antenna having the fourth resonant frequency.

13. The antenna module according to claim 11 or 12, wherein, The fourth resonant frequency is the same communication frequency band as the second resonant frequency.

14. An electronic device comprising: The antenna module according to any one of claims 1 to 13; and A substrate for mounting the antenna module.

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