CN108900217B

CN108900217B - Tuning circuit, radio frequency circuit and electronic equipment

Info

Publication number: CN108900217B
Application number: CN201810759353.8A
Authority: CN
Inventors: 贾玉虎
Original assignee: Oppo Chongqing Intelligent Technology Co Ltd
Current assignee: Oppo Chongqing Intelligent Technology Co Ltd
Priority date: 2018-07-11
Filing date: 2018-07-11
Publication date: 2021-01-08
Anticipated expiration: 2038-07-11
Also published as: CN108900217A

Abstract

The embodiment of the application provides a tuning circuit, a radio frequency circuit and an electronic device, wherein the tuning circuit comprises: the variable capacitor comprises an input end and an output end, wherein the input end of the variable capacitor is used for connecting a signal source, and the output end of the variable capacitor is used for connecting an antenna radiating body; the first switch is connected with the input end and the output end of the variable capacitor; the second switch is connected with the input end of the variable capacitor and grounded; the third switch is connected with the output end of the variable capacitor and grounded; and the fourth switch is connected with the output end of the variable capacitor and grounded. The tuning circuit can tune and output radio frequency signals with different frequencies according to the capacitance value of the variable capacitor and the states of the first switch, the second switch, the third switch and the fourth switch, so that the diversity of communication frequency bands of the electronic equipment can be improved.

Description

Tuning circuit, radio frequency circuit and electronic equipment

Technical Field

The present application relates to the field of communications technologies, and in particular, to a tuning circuit, a radio frequency circuit, and an electronic device.

Background

With the development of communication technology, electronic devices such as smart phones are capable of supporting more and more communication bands. For example, an LTE (Long Term Evolution) communication signal may include a radio frequency signal having a frequency between 700MHz and 2700 MHz.

Radio frequency signals that can be supported by an electronic device can be divided into low frequency signals, intermediate frequency signals, and high frequency signals. The low-frequency signal, the intermediate-frequency signal and the high-frequency signal respectively comprise a plurality of sub-frequency band signals. Each sub-band signal needs to be transmitted to the outside world via an antenna.

Currently, the frequency resources of the various communication markets around the world are different from each other. Communication operators in different regions have different communication spectrum allocations, so that communication demands of radio frequency signals in different frequency bands exist. However, the current electronic devices lack diversity of the communication frequency bands to be tuned, and cannot meet the above requirements.

Disclosure of Invention

The embodiment of the application provides a tuning circuit, a radio frequency circuit and an electronic device, which can improve the diversity of communication frequency bands of the electronic device.

An embodiment of the present application provides a tuning circuit, including:

the variable capacitor comprises an input end and an output end, wherein the input end of the variable capacitor is used for connecting a signal source, and the output end of the variable capacitor is used for connecting an antenna radiating body;

the first switch is connected with the input end and the output end of the variable capacitor;

the second switch is connected with the input end of the variable capacitor and grounded;

the third switch is connected with the output end of the variable capacitor and grounded;

and the fourth switch is connected with the output end of the variable capacitor and grounded.

The embodiment of the application also provides a radio frequency circuit, which comprises a signal source, a tuning circuit and an antenna radiator, wherein the signal source, the tuning circuit and the antenna radiator are sequentially connected;

the signal source is used for generating radio frequency signals;

the tuning circuit is used for tuning the radio frequency signal, and the tuning circuit is the tuning circuit;

the antenna radiator is used for transmitting the tuned radio frequency signal to the outside.

The embodiment of the application further provides an electronic device, which comprises a shell and a radio frequency circuit arranged inside the shell, wherein the radio frequency circuit is the radio frequency circuit.

The tuning circuit provided by the embodiment of the application can tune and output radio frequency signals with different frequencies according to the capacitance value of the variable capacitor and the states of the first switch, the second switch, the third switch and the fourth switch, so that the diversity of communication frequency bands of electronic equipment can be improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings used in the description of the embodiments will be briefly introduced below. It is obvious that the drawings in the following description are only some embodiments of the application, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

Fig. 1 is a first structural schematic diagram of an electronic device according to an embodiment of the present application.

Fig. 2 is a second schematic structural diagram of an electronic device according to an embodiment of the present application.

Fig. 3 is an exploded view of the electronic device shown in fig. 1.

Fig. 4 is a schematic diagram of a first structure of a radio frequency circuit according to an embodiment of the present disclosure.

Fig. 5 is a schematic diagram of a second structure of the rf circuit according to the embodiment of the present disclosure.

Fig. 6 is a schematic diagram of a third structure of a radio frequency circuit according to an embodiment of the present application.

Fig. 7 is a schematic diagram of a fourth structure of a radio frequency circuit according to an embodiment of the present application.

Fig. 8 is a fifth structural schematic diagram of a radio frequency circuit according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, terms such as "first", "second", are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined by terms such as "first," "second," etc., may explicitly or implicitly include one or more of the recited features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

The following disclosure provides many different embodiments or examples for implementing different features of the application. In order to simplify the disclosure of the present application, specific example components and arrangements are described below. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. In addition, examples of various specific processes and materials are provided herein, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.

The embodiment of the application provides electronic equipment. The electronic device may be a smart phone, a tablet computer, or other devices, and may also be a game device, an AR (Augmented Reality) device, an automobile, a data storage device, an audio playing device, a video playing device, a notebook, a desktop computing device, or other devices.

In some embodiments, referring to fig. 1 and 3, the electronic device 100 includes a display screen 11, a middle frame 12, a circuit board 13, a battery 14, and a rear cover 15.

The display screen 11 may be mounted on the middle frame 12 and connected to the rear cover 15 through the middle frame 12 to form a display surface of the electronic device 100. The display screen 11 serves as a front case of the electronic device 100, and forms a housing of the electronic device 100 together with the rear cover 15 for accommodating other electronic elements or functional components of the electronic device 100. Meanwhile, the display screen 11 forms a display surface of the electronic apparatus 100 for displaying information such as images, texts, and the like. The Display screen 11 may be a Liquid Crystal Display (LCD) or an Organic Light-Emitting Diode (OLED) Display screen.

In some embodiments, a glass cover plate may be disposed over the display screen 11. The glass cover plate may cover the display screen 11 to protect the display screen 11 and prevent the display screen 11 from being scratched or damaged by water.

In some embodiments, as shown in FIG. 1, the display screen 11 may include a display area 111 and a non-display area 112. The display area 111 performs a display function of the display screen 11 for displaying information such as images and texts. The non-display area 112 may be used to set up functional elements such as a distance sensor, a receiver, and a touch electrode of a display screen. In some embodiments, the non-display area 112 may include at least one area located above and below the display area 111.

In some embodiments, as shown in FIG. 2, the display screen 11 may be a full-face screen. At this time, the display screen 11 may display information in a full screen, so that the electronic apparatus 100 has a large screen occupation ratio. The display screen 11 includes only the display region 111 and does not include the non-display region, or the area of the non-display region is small. In this case, functional components such as a distance sensor and an ambient light sensor in the electronic device 100 may be hidden under the display screen 11, and the fingerprint recognition module of the electronic device 100 may be disposed on the back of the electronic device 100.

The middle frame 12 may have a thin plate-like or sheet-like structure, or may have a hollow frame structure. The middle frame 12 may be accommodated in a housing formed by the display panel 11 and the rear cover 15. The middle frame 12 is used for providing a supporting function for the electronic components or functional modules in the electronic device 100, so as to mount the electronic components or functional modules in the electronic device together. For example, functional components such as a receiver, a circuit board, and a battery in the electronic apparatus may be mounted on the center frame 12 for fixing. In some embodiments, the material of the middle frame 12 may include metal or plastic.

The circuit board 13 is mounted inside the housing of the electronic device 100. The circuit board 13 may be a main board of the electronic device 100. The circuit board 13 is provided with a grounding point to realize grounding of the circuit board 13. The circuit board 13 has processing circuitry integrated thereon. The processing circuit is used for processing applications and data in the electronic device 100. One, two or more of the functional components such as a motor, a microphone, a speaker, a receiver, an earphone interface, a universal serial bus interface (USB interface), a distance sensor, an ambient light sensor, a gyroscope, etc. may also be integrated on the circuit board 13. Meanwhile, the display screen 11 may be electrically connected to the circuit board 13.

The battery 14 is mounted inside the housing of the electronic device 100. Wherein, the battery 14 can be electrically connected to the circuit board 13 to enable the battery 14 to supply power to the electronic device 100. Wherein, the circuit board 13 may be provided with a power management circuit. The power management circuit is used to distribute the voltage provided by battery 14 to the various electronic components in electronic device 100.

The rear cover 15 is used to form an outer contour of the electronic apparatus 100. The rear cover 15 may be integrally formed. In the forming process of the rear cover 15, structures such as a rear camera hole and a fingerprint identification module mounting hole can be formed on the rear cover 15.

In this embodiment, the electronic device 100 is further provided with a radio frequency circuit. The radio frequency circuitry is disposed inside a housing of the electronic device 100. The radio frequency circuit is used for transmitting radio frequency signals to the outside and receiving radio frequency signals from the outside. For example, the radio frequency circuitry may be used to transmit radio frequency signals to a base station or other electronic device, and to receive radio frequency signals transmitted by a base station or other electronic device. Thus, communication of the electronic device with the base station and other electronic devices can be achieved.

Referring to fig. 4, the radio frequency circuit 20 includes a signal source 21, a tuning circuit 22, and an antenna radiator 23. The signal source 21, the tuning circuit 22 and the antenna radiator 23 are connected in sequence.

Wherein the signal source 21 and the tuning circuit 22 may be arranged on the circuit board 13 of the electronic device 100. The antenna radiator 23 may be provided on the middle frame 12 of the electronic device 100, or may also be provided on the rear cover 15, or an antenna holder may also be provided separately in the electronic device 100, and the antenna radiator 23 may be provided on the antenna holder. Further, the antenna radiator 23 is grounded.

In some embodiments, the number of the antenna radiators 23 may be multiple, and the multiple antenna radiators 23 are spaced apart from each other. For example, one antenna radiator 23 may be disposed at each of the upper right corner, the lower left corner, and the lower right corner of the electronic device 100. Each of the antenna radiators 23 is grounded.

In some embodiments, the middle frame 12 of the electronic device 100 may have a metal extension formed thereon. For example, one or more slits may be cut into the center frame 12, through which elongated metal extensions are formed on the center frame 12. The metal extension formed on the middle frame 12 may serve as the antenna radiator 23.

Wherein the signal source 21 is used for generating a radio frequency signal. For example, the signal source 21 may include a high frequency oscillation circuit. The high frequency oscillation circuit generates a radio frequency signal under the control of the processor of the electronic device 100.

The tuning circuit 22 is configured to tune the radio frequency signal generated by the signal source 21 to form radio frequency signals with different frequencies according to actual requirements.

The antenna radiator 23 is used for transmitting the radio frequency signal tuned by the tuning circuit 22 to the outside. In addition, the antenna radiator 23 may also receive radio frequency signals from the outside, and transmit the radio frequency signals to the processor of the electronic device 100 for processing.

In some embodiments, as shown in fig. 5, tuning circuit 22 includes a variable capacitance 221, a first switch 222, a second switch 223, a third switch 224, and a fourth switch 225.

The capacitance of the variable capacitor 221 can be adjusted according to actual requirements. For example, the capacitance value of the variable capacitor 221 may be adjusted to a capacitance value such as 0.5pF (picofarad), 1.5pF, 3pF, or the like. The variable capacitor 221 includes an input terminal a and an output terminal B. The input end a of the variable capacitor 221 is used for connecting the signal source 21. The output end B of the variable capacitor 221 is used for connecting the antenna radiator 23. Further, the antenna radiator 23 is grounded.

The first switch 222 is connected to the input terminal a and the output terminal B of the variable capacitor 221. That is, the first switch 222 is connected in parallel with the variable capacitor 221. The first switch 222 is used to control the variable capacitor 221 to be short-circuited or switched on, that is, to control the variable capacitor 221 to be operated or not to be operated.

The second switch 223 is connected to the input terminal a of the variable capacitor 221 and grounded. When one end of the second switch 223 is connected to the input end a of the variable capacitor 221, the connection point is located between the input end a of the variable capacitor 221 and the signal source 21. The other end of the second switch 223 is grounded.

The third switch 224 is connected to the output terminal B of the variable capacitor 221 and grounded. When one end of the third switch 224 is connected to the output end B of the variable capacitor 221, the connection point is located between the output end B of the variable capacitor 221 and the antenna radiator 23. The other end of the third switch 224 is connected to ground.

The fourth switch 225 is connected to the output terminal B of the variable capacitor 221 and grounded. When one end of the fourth switch 225 is connected to the output end B of the variable capacitor 221, the connection point is located between the output end B of the variable capacitor 221 and the antenna radiator 23. The other end of the fourth switch 225 is grounded.

In some embodiments, the first switch 222, the second switch 223, the third switch 224, and the fourth switch 225 are all single-pole, single-throw switches.

In some embodiments, the variable capacitor 221 and the first switch 222, the second switch 223, the third switch 224, and the fourth switch 225 may be packaged as an integrated chip.

Accordingly, the tuning circuit 22 can tune and output radio frequency signals with different frequencies according to the capacitance value of the variable capacitor 221 and the states of the first switch 222, the second switch 223, the third switch 224 and the fourth switch 225.

In some embodiments, as shown in fig. 6, the tuning circuit 22 further includes a first tuning element 226, a second tuning element 227, and a third tuning element 228.

Wherein the first tuning element 226 is connected in series between the second switch 223 and the input a of the variable capacitor 221. The connection point between the first tuning element 226 and the input a of the variable capacitance 221 is located between the input a of the variable capacitance 221 and the signal source 21. In some embodiments, the first tuning element 226 may be a first capacitor or a first inductor. The capacitance of the first capacitor or the inductance of the first inductor can be selected according to actual requirements.

The second tuning element 227 is connected in series between the third switch 224 and the output terminal B of the variable capacitor 221. A connection point between the second tuning element 227 and the output end B of the variable capacitor 221 is located between the output end B of the variable capacitor 221 and the antenna radiator 23. In some embodiments, the second tuning element 227 may be a second capacitor or a second inductor. The capacitance of the second capacitor or the inductance of the second inductor can be selected according to actual requirements.

The third tuning element 228 is connected in series between the fourth switch 225 and the output B of the variable capacitor 221. A connection point between the third tuning element 228 and the output terminal B of the variable capacitor 221 is located between the output terminal B of the variable capacitor 221 and the antenna radiator 23. In some embodiments, the third tuning element 228 may be a third capacitor or a third inductor. The capacitance of the third capacitor or the inductance of the third inductor can be selected according to actual requirements.

In the tuning circuit 22, the electronic device may control states of the first switch 222, the second switch 223, the third switch 224, and the fourth switch 225, so as to enable the variable capacitor 221 to operate or not operate, and at the same time, may enable one or more capacitors, one or more inductors, or a combination of capacitors and inductors to be connected in the tuning circuit 22, so as to tune and output radio frequency signals of different frequencies.

In some embodiments, as shown in fig. 7, the tuning circuit 22 also includes a single-pole, multi-throw switch 229. The single-pole-multi-throw switch 229 is connected to the output terminal B of the variable capacitor 221 and grounded. Wherein the single-pole-multiple-throw switch 229 comprises a plurality of inputs and an output. A plurality of input terminals of the single-pole-multi-throw switch 229 are connected to the output terminal B of the variable capacitor 221. The output of the single pole, multiple throw switch 229 is connected to ground. The output of the single-pole-multiple-throw switch 229 may or may not be connected to any of a plurality of inputs.

The input terminals of the single-pole-multi-throw switch 229 and the output terminal B of the variable capacitor 221 are connected to the antenna radiator 23. That is, the antenna radiator 23 is connected between the input terminals of the single pole, multi-throw switch 229 and the output terminal B of the variable capacitor 221.

In some embodiments, as shown in fig. 8, the single-pole-multiple-throw switch 229 includes a first input C, a second input D, a third input E, a fourth input F, and an output G. Wherein the output terminal G is grounded. The output terminal G may be connected to any one of the first input terminal C, the second input terminal D, the third input terminal E, and the fourth input terminal F, or may not be connected to any one of the input terminals.

A fourth tuning element 231 is connected in series between the first input terminal C and the output terminal B of the variable capacitor 221. A fifth tuning element 232 is connected in series between the second input terminal D and the output terminal B of the variable capacitor 221. A sixth tuning element 233 is connected in series between the third input E and the output B of the variable capacitor 221.

When the output G switches on the first input C, the fourth tuning element 231 switches on the circuit. When the output terminal G is connected to the second input terminal D, the fifth tuning element 232 is connected to the circuit. When the output terminal G is connected to the third input terminal E, the sixth tuning element 233 is connected to the circuit. When the output terminal G is connected to the fourth input terminal F, no additional tuning element is connected to the circuit, and at this time, the single-pole multi-throw switch 229 is grounded, that is, the output terminal B of the variable capacitor 221 is grounded through the single-pole multi-throw switch 229.

In some embodiments, the fourth tuning element 231 may be a fourth capacitor or a fourth inductor. The fifth tuning element 232 may be a fifth capacitor or a fifth inductor. The sixth tuning element 233 may be a sixth capacitor or a sixth inductor. And the capacitance or inductance of the fourth capacitor or the fourth inductor, the fifth capacitor or the fifth inductor, the sixth capacitor or the sixth inductor can be selected according to actual requirements.

In some embodiments, as shown in fig. 8, the radio frequency circuitry 20 also includes control circuitry 24. The control circuit 24 is connected to the tuning circuit 22. The control circuit 24 may be configured to control a capacitance value of the variable capacitor 221, and may also be configured to control on or off states of the first switch 222, the second switch 223, the third switch 224, and the fourth switch 225, and may also be configured to control an on state of the single-pole multi-throw switch 229.

Wherein, when the first switch 222, the second switch 223, the third switch 224 and the fourth switch 225 are all turned off, and the output terminal G of the single-pole-multiple-throw switch 229 is turned on the first input terminal C or the second input terminal D or the third input terminal E, the tuning circuit 22 can be used for outputting the radio frequency signal of the first frequency range. At this time, the variable capacitor 221 is in an operating state. The fourth 231 or fifth 232 or sixth 233 tuning element is switched into the circuit.

In some embodiments, the capacitance value of the variable capacitor 221 may be between 0.75pF and 1.5 pF. The first frequency range is 700MHz to 900 MHz.

When the first switch 222 is turned on, the output terminal G of the single-pole-multiple-throw switch 229 is turned on the fourth input terminal F, and the second switch 223 or the third switch 224 or the fourth switch 225 is turned on, the tuning circuit 22 may be configured to output radio frequency signals of a second frequency range. At this time, the variable capacitor 221 is in an inactive state. The first tuning element 226 or the second tuning element 227 or the third tuning element 228 is switched into the circuit.

In some embodiments, the second frequency range is 1710MHz to 2170 MHz.

When the first switch 222, the second switch 223, the third switch 224, the fourth switch 225, and the single-pole-multi-throw switch 229 are all open, the tuning circuit 22 may be configured to output radio frequency signals in a third frequency range. At this time, the variable capacitor 221 is in an operating state. The tuning circuit 22 is grounded via the grounding point of the antenna radiator 23.

In some embodiments, the capacitance value of the variable capacitor 221 may be between 0.75pF and 1.5 pF. The third frequency range is 2300MHz to 2700 MHz.

When the first switch 222, the fourth switch 225, and the single-pole-multi-throw switch 229 are all off, and the second switch 223 and the third switch 224 are all on, the tuning circuit 22 may be configured to output radio frequency signals at a fourth frequency range. At this time, the variable capacitor 221 is in an operating state. The first tuning element 226 and the second tuning element 227 are connected into a circuit.

In some embodiments, the capacitance value of the variable capacitor 221 may be between 2pF and 3 pF. The fourth frequency range is 1428MHz to 1511 MHz.

In this embodiment, the electronic device 100 may control the tuning circuit 22 to output radio frequency signals with different frequencies by controlling the capacitance value of the variable capacitor 221 in the tuning circuit 22 and controlling the states of the first switch 222, the second switch 223, the third switch 224, the fourth switch 225, and the single-pole multi-throw switch 229, so as to improve the diversity of the communication frequency bands of the electronic device.

The tuning circuit, the radio frequency circuit and the electronic device provided by the embodiment of the application are described in detail above. The principles and implementations of the present application are described herein using specific examples, which are presented only to aid in understanding the present application. Meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. A tuning circuit, comprising:

the second switch is connected with the input end of the variable capacitor and grounded to a first grounding point, and the connection point of the second switch and the variable capacitor is positioned between the input end of the variable capacitor and the signal source;

a third switch connected to the output terminal of the variable capacitor and grounded to a second ground point, wherein a connection point of the third switch and the variable capacitor is located between the output terminal of the variable capacitor and the antenna radiator;

a fourth switch connected to the output terminal of the variable capacitor and grounded to a third ground point, a connection point of the fourth switch and the variable capacitor being located between the output terminal of the variable capacitor and the antenna radiator;

the single-pole multi-throw switch comprises a plurality of input ends and an output end, the plurality of input ends of the single-pole multi-throw switch are all connected with the output end of the variable capacitor, the output end of the single-pole multi-throw switch is grounded to a fourth grounding point, and the plurality of input ends of the single-pole multi-throw switch and the output end of the variable capacitor are used for being connected with the antenna radiator;

the tuning circuit outputs radio frequency signals with different frequencies according to the capacitance value of the variable capacitor and different on states of the first switch, the second switch, the third switch, the fourth switch, the single-pole multi-throw switch, the first grounding point, the second grounding point, the third grounding point and the fourth grounding point.

2. The tuning circuit of claim 1, wherein:

a first capacitor or a first inductor is connected in series between the second switch and the input end of the variable capacitor;

a second capacitor or a second inductor is connected in series between the third switch and the output end of the variable capacitor;

and a third capacitor or a third inductor is connected in series between the fourth switch and the output end of the variable capacitor.

3. The tuning circuit according to claim 1, wherein the single-pole-multiple-throw switch comprises a first input terminal, a second input terminal, a third input terminal, and a fourth input terminal, a fourth capacitor or a fourth inductor is connected in series between the first input terminal and the output terminal of the variable capacitor, a fifth capacitor or a fifth inductor is connected in series between the second input terminal and the output terminal of the variable capacitor, and a sixth capacitor or a sixth inductor is connected in series between the third input terminal and the output terminal of the variable capacitor.

4. The tuning circuit of claim 3, wherein when the first switch, the second switch, the third switch, and the fourth switch are all off and the output of the single-pole-multiple-throw switch is on the first input or the second input or the third input, the tuning circuit is operable to output radio frequency signals in a first frequency range.

5. The tuned circuit of claim 3, wherein when the first switch is on, the output of the single-pole, multi-throw switch is on, the fourth input is on, and the second switch or the third switch or the fourth switch is on, the tuned circuit is operable to output radio frequency signals for a second range of frequencies.

6. The tuning circuit of claim 3, wherein the tuning circuit is operable to output radio frequency signals in a third frequency range when the first switch, the second switch, the third switch, the fourth switch, and the single-pole-multi-throw switch are all open.

7. The tuning circuit of claim 3, wherein when the first switch, the fourth switch, and the single-pole-multiple-throw switch are all off and the second switch and the third switch are all on, the tuning circuit is operable to output radio frequency signals for a fourth frequency range.

8. A radio frequency circuit is characterized by comprising a signal source, a tuning circuit and an antenna radiator, wherein the signal source, the tuning circuit and the antenna radiator are sequentially connected;

the signal source is used for generating radio frequency signals;

the tuning circuit is used for tuning the radio frequency signal, and the tuning circuit is the tuning circuit in any one of claims 1 to 7;

9. An electronic device comprising a housing and a radio frequency circuit disposed inside the housing, the radio frequency circuit being the radio frequency circuit of claim 8.