Antenna gain switching circuit, antenna and wireless audio system

Abstract

The utility model relates to an antenna gain switching circuit for a wireless audio system, an antenna and the wireless audio system, a passive channel and an active gain channel of the antenna gain switching circuit can be alternatively connected, so that the antenna can be connected through the passive channel under the condition that an antenna interface (namely a second interface) is not fed, and the antenna gain switching circuit can be used for switching the antenna. As a passive antenna, under the condition that the antenna interface can provide a feed signal, the antenna is connected through the active gain channel to become an active antenna, so that the problem that the antenna cannot be compatible with active and passive scenes during product use is solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power electronics, and particularly relates to an antenna gain switching circuit for a wireless audio system, an antenna and a wireless audio system. BACKGROUND

[0002] In the process of filming, interviewing and creating, a wireless audio communication system is often needed. A wireless audio communication environment needs to be built in the whole process of filming. A receiving antenna system is an indispensable part in the environment. The antenna has a part of the scene used outdoors, and thus needs to be rainproof. The receiving antenna provides a longer and better communication distance and audio quality for the system in the whole wireless audio system.

[0003] In the prior art, the receiving antenna is used for receiving audio signals from a transmitting antenna in a wireless audio receiving system. The receiving antenna is divided into two forms of passive antenna and active antenna. The passive antenna has no low noise amplifier (LNA), and in the case that the antenna and the receiver are far away from each other, for example, in a concert, the line loss is large, and the receiving antenna system cannot be provided with gain compensation. When the active antenna is used, the receiving antenna needs to be fed through an antenna interface to compensate the gain. However, in the actual use, most receivers cannot feed the external antenna. CONTENT OF THE UTILITY MODEL

[0004] The application aims to provide an antenna gain switching circuit for a wireless audio system, an antenna and a wireless audio system, and aims to solve the problem that the antenna cannot be compatible with active and passive scenes in the related art.

[0005] In a first aspect, an antenna gain switching circuit for a wireless audio system is provided, and the antenna gain switching circuit comprises:

[0006] a first interface configured to connect a passive antenna;

[0007] a second interface configured to connect a receiver of a wireless audio system to output a radio frequency signal to the receiver, or configured to connect a transmitter of the wireless audio system to receive a radio frequency signal output by the transmitter;

[0008] a passive channel connected between the first interface and the second interface, configured to directly transmit a radio frequency signal between the first interface and the second interface;

[0009] An active gain channel is connected between the first interface and the second interface. The passive channel and the active gain channel are selectively turned on. The active gain channel is used to gain the radio frequency signal between the first interface and the second interface based on the feed signal accessed by the second interface.

[0010] In some embodiments, it also includes:

[0011] A power supply circuit, connected to the second interface, is used to output a power supply signal based on the power supply signal;

[0012] A switching circuit is connected to the first interface, the second interface, the passive channel, the passive channel, and the power supply circuit. The switching circuit is used to turn on the passive channel and turn off the active gain channel when the power supply signal is not received.

[0013] A first control circuit is connected to the power supply circuit and the switching circuit. The first control circuit is used to control the switching circuit to disconnect the passive channel and connect the active gain channel based on the power supply signal.

[0014] In some embodiments, the active gain channel includes:

[0015] A gain circuit is connected to the power supply circuit and to the first interface and the second interface through the switching circuit. The gain circuit is used to increase the radio frequency signal between the first interface and the second interface based on the power supply signal.

[0016] In some embodiments, the active gain channel further includes:

[0017] A detection circuit, connected to the gain circuit, is used to detect the gain of the RF signal after gain adjustment and output a detection signal corresponding to the gain.

[0018] The second control circuit is connected to the detection circuit, the power supply circuit and the gain circuit, and is used to adjust the gain of the gain circuit to the radio frequency signal according to the detection signal output adjustment signal.

[0019] In some embodiments, the gain circuit includes:

[0020] A first filtering circuit, the input terminal of which is connected to the first interface and the second interface as the input side, is used to perform a first filtering on the radio frequency signal.

[0021] An amplifier circuit, wherein the input terminal of the amplifier circuit is connected to the output terminal of the first filter circuit, and the output terminal is connected to the detector circuit, and the amplifier circuit is used to preset the gain of the radio frequency signal after the first filter.

[0022] An adjustment circuit is provided, wherein the input terminal of the adjustment circuit is connected to the output terminal of the amplifier circuit, the adjustment terminal of the adjustment circuit is connected to the second control circuit, and the output terminal of the adjustment circuit is connected to the output side of the first interface and the second interface. The adjustment circuit is used to adjust the gain of the radio frequency signal after the preset gain according to the adjustment signal.

[0023] In some embodiments, the gain circuit further includes:

[0024] The second filter circuit is connected to the output of the adjustment circuit and is used to perform a second filter on the gain-adjusted radio frequency signal.

[0025] In some embodiments, a first button is also included, the first button being connected to the first control circuit, and the first button being used to output a first button signal according to user operation;

[0026] The first control circuit is further configured to control the switching circuit to disconnect the passive channel and connect the active gain channel, or connect the passive channel and disconnect the active gain channel, according to the first key signal.

[0027] In some embodiments, a second button is also included, the second button being connected to the second control circuit, and the second button being used to output a second button signal according to user operation;

[0028] The second control circuit is also used to adjust or fix the adjustment signal according to the second key signal.

[0029] In some embodiments, the second control circuit and the first control circuit are integrated into the same control chip.

[0030] In some embodiments, the first control circuit includes a transistor, a first resistor, and a second resistor, and the second control circuit includes a control chip.

[0031] The first end of the first resistor is connected to the output terminal of the power supply circuit, the second end of the first resistor is connected to the first end of the second resistor and the base of the transistor, the second end of the second resistor is connected to the control pin of the control chip, the collector of the transistor is connected to the switching circuit, and the emitter of the transistor is grounded.

[0032] In some embodiments, the switching circuit includes:

[0033] The drive module is connected to the first control circuit and the power supply circuit;

[0034] The first switch module includes a first control part, a first normally closed switch and a second normally closed switch. The first control part is connected to the drive module. The first normally closed switch and the second normally closed switch are connected in series between the first interface and the second interface to form the passive channel.

[0035] The second switch module includes a second control section, a first normally open switch, and a second normally open switch. The second control section is connected to the drive module. The moving contact of the first normally open switch is connected to the first interface, and the moving contact of the second normally open switch is connected to the second interface. The active gain channel is connected between the normally open contact of the first normally open switch and the normally open contact of the second normally open switch.

[0036] In some embodiments, the first control part and the second control part are the same, the first normally closed switch and the first normally open switch share the same moving contact, and the second normally closed switch and the second normally open switch share the same moving contact.

[0037] Secondly, embodiments of this application also provide an antenna, including a passive antenna, a circuit board, and an antenna gain switching circuit as described above.

[0038] Thirdly, embodiments of this application also provide a wireless audio system, including the antenna and receiver as described above, wherein the antenna is connected to the receiver; or including the antenna and transmitter as described above, wherein the antenna is connected to the transmitter.

[0039] The beneficial effects of this application embodiment compared with related technologies are: the passive channel and active gain channel of the antenna gain switching circuit for the wireless audio system can be selectively connected, allowing the antenna to be connected through the passive channel as a passive antenna when there is no power supply to the antenna interface (i.e., the second interface). When the antenna interface can provide a power supply signal, the antenna is connected through the active gain channel and becomes an active antenna, thus solving the problem that the antenna cannot be compatible with active and passive scenarios in the use of the product. Attached Figure Description

[0040] Figure 1 A block diagram of an antenna gain switching circuit for a wireless audio system provided in Embodiment 1 of this application;

[0041] Figure 2 This is a block diagram of an antenna gain switching circuit for a wireless audio system provided in Embodiment 2 of this application;

[0042] Figure 3A block diagram of the active gain channel in the antenna gain switching circuit provided in Embodiment 3 of this application;

[0043] Figure 4 A block diagram of the active gain channel in the antenna gain switching circuit provided in Embodiment 4 of this application;

[0044] Figure 5 This is a block diagram of the active gain channel in the antenna gain switching circuit provided in Embodiment 5 of this application;

[0045] Figure 6 This is a block diagram of the active gain channel in the antenna gain switching circuit provided in Embodiment Six of this application;

[0046] Figure 7 A block diagram of an antenna gain switching circuit for a wireless audio system provided in Embodiment 7 of this application;

[0047] Figure 8 A block diagram of an antenna gain switching circuit for a wireless audio system provided in Embodiment 8 of this application;

[0048] Figure 9 This is a circuit diagram of the switching circuit in the antenna gain switching circuit provided in Embodiment 4 of this application;

[0049] Figure 10 This is a circuit diagram of the switching circuit in the antenna gain switching circuit provided in Embodiment 5 of this application. Detailed Implementation

[0050] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0051] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0052] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0054] Wireless audio communication systems are frequently used in film and television productions, variety shows, movie shooting, concerts, interviews, and creative processes. A wireless audio communication environment needs to be set up throughout the entire shooting process. The receiving antenna is an indispensable component in this environment; some antenna usage scenarios are outdoors, and the antenna needs to be rainproof. In the entire wireless audio system, the receiving antenna provides the system with a longer and better communication distance and audio quality.

[0055] In existing technology, antennas are connected to wireless audio receiving systems to receive audio signals from transmitting antennas. Antennas are divided into two types: passive antennas and active antennas. Passive antennas lack a low-noise amplifier (LNA) sections, resulting in significant line loss when the antenna and receiver are far apart, such as at concerts, making it impossible to provide gain compensation for the receiving system. Active antennas require the receiving system to provide power through the antenna interface to compensate for gain; however, in current practical applications, most receiver systems cannot power external antennas through their antenna ports. Therefore, it is necessary to provide an antenna gain switching circuit for wireless audio systems, enabling the antenna to automatically switch: when there is power at the antenna port, it automatically becomes an active antenna; when the antenna port cannot provide power, the antenna automatically becomes a passive antenna.

[0056] like Figure 1 As shown, one embodiment of this application provides an antenna gain switching circuit 100 for a wireless audio system. The antenna gain switching circuit 100 includes a first interface 110, a second interface 120, a passive channel 130, and an active gain channel 140.

[0057] The first interface 110 is used to connect a passive antenna (hereinafter referred to as antenna) 200; the second interface 120 is used to connect a receiver of a wireless audio system to output radio frequency signals to the receiver, or to connect a transmitter of a wireless audio system to receive radio frequency signals output by the transmitter; the passive channel 130 is connected between the first interface 110 and the second interface 120 and is used to directly transmit radio frequency signals between the first interface 110 and the second interface 120; the active gain channel 140 is connected between the first interface 110 and the second interface 120, and one of the passive channel 130 and the active gain channel 140 is selectively turned on. The active gain channel 140 is used to gain the radio frequency signal between the first interface 110 and the second interface 120 based on the feed signal accessed by the second interface 120.

[0058] In the technical solution of this application, the gain switching circuit 100 of the antenna 200 provides a passive channel 130 and an active gain channel 140 for the passive antenna 200 (hereinafter referred to as antenna 200). When the passive channel 130 is turned on, the antenna 200 connects to the second interface 120 through the passive channel 130 and connects to the receiver or transmitter of the wireless audio system. The antenna 200 will work in a passive state. When the active gain channel 140 is turned on, the antenna 200 connects to the second interface 120 through the active gain channel 140 and connects to the receiver or transmitter of the wireless audio system. The antenna 200 will work in an active gain state, thereby enabling the antenna 200 to adapt to different application scenarios.

[0059] like Figure 2 As shown, in some embodiments, the antenna 200 gain switching circuit 100 further includes a power supply circuit 150, a switching circuit 160, and a first control circuit 170.

[0060] The power supply circuit 150 is connected to the second interface 120 and is used to output a power supply signal based on the power supply signal; the switching circuit 160 is connected to the first interface 110, the second interface 120, the passive channel 130, and the power supply circuit 150. The switching circuit 160 is used to turn on the passive channel 130 and turn off the active gain channel 140 when no power supply signal is received; the first control circuit 170 is connected to the power supply circuit 150 and the switching circuit 160. The first control circuit 170 is used to control the switching circuit 160 to turn off the passive channel 130 and turn on the active gain channel 140 based on the power supply signal.

[0061] The power supply circuit 150 is, for example, a DC-DC circuit / chip or an LDO (low dropout regulator), used to convert the feed signal into a power supply signal output. The switching circuit 160 is, for example, a circuit module composed of electronic switches such as relays or semiconductor switches. The first control circuit 170 is, for example, a circuit module composed of a control chip and / or electronic switches.

[0062] In this embodiment, the passive channel 130 can be turned on and the active gain channel 140 can be selectively turned on by the power supply circuit 150, the switching circuit 160 and the first control circuit 170, thereby controlling the antenna 200 to work in active gain state or passive state.

[0063] like Figure 3 As shown, in some embodiments, the active gain channel 140 includes a gain circuit 141, which is connected to the power supply circuit 150 and to the first interface 110 and the second interface 120 through a switching circuit 160. The gain circuit 141 is used to gain the radio frequency signal between the first interface 110 and the second interface 120 based on the power supply signal.

[0064] like Figure 4 As shown, in some embodiments, the active gain channel 140 further includes a detection circuit 142 and a second control circuit 143.

[0065] The detection circuit 142 is connected to the gain circuit 141 and is used to detect the gain of the RF signal after gain adjustment, and output a detection signal corresponding to the gain. The detection circuit 142 determines the gain of the RF signal by detecting its waveform and / or amplitude and outputs a detection signal corresponding to the gain.

[0066] The second control circuit 143 is connected to the detection circuit 142, the power supply circuit 150, and the gain circuit 141, and is used to adjust the gain of the gain circuit 141 on the radio frequency signal according to the detection signal. The second control circuit 143 operates based on the power supply of the power supply circuit 150, reads the detection signal from the detection circuit 142, compares the detection signal with a preset or input gain adjustment signal, and generates an adjustment signal based on the comparison result to adjust the gain of the gain circuit 141 on the radio frequency signal.

[0067] The second control circuit 143 is, for example, a microprocessor. The detection circuit 142 can be a conventional radio frequency detection circuit 142 or a chip.

[0068] like Figure 5 As shown, in some embodiments, the gain circuit 141 includes a first filter circuit 1411, an amplifier circuit 1412, and an adjustment circuit 1413.

[0069] The input terminal of the first filter circuit 1411 is connected to the input side interface of the first interface 110 and the second interface 120. The first filter circuit 1411 is used to perform a first filter on the radio frequency signal. The input terminal of the amplifier circuit 1412 is connected to the output terminal of the first filter circuit 1411, and the output terminal is connected to the detector circuit 142. The amplifier circuit 1412 is used to preset the gain of the radio frequency signal after the first filter. The input terminal of the adjustment circuit 1413 is connected to the output terminal of the amplifier circuit 1412, the adjustment terminal of the adjustment circuit 1413 is connected to the second control circuit 143, and the output terminal of the adjustment circuit 1413 is connected to the output side interface of the first interface 110 and the second interface 120. The adjustment circuit 1413 is used to adjust the gain of the radio frequency signal after the preset gain according to the adjustment signal.

[0070] In this embodiment, antenna 200 serves as a transmitting antenna. The input terminal of the first filtering circuit 1411 is connected to the second interface 120, which serves as an input-side interface connected to the transmitter of the wireless audio system. The first filtering circuit 1411 is primarily used to filter out high-frequency spurious signals (signals above 1 GHz). The amplifier circuit 1412 is, for example, a low-noise amplifier, primarily amplifying the useful radio frequency signal. The adjustment circuit 1413 is, for example, a digital attenuator, primarily attenuating the radio frequency signal and used to control the gain of the radio frequency signal.

[0071] The detection circuit 142 demodulates the gain of the RF signal into a DC signal (i.e., the detection signal), which is then sent to the ADC port of the second control circuit 143. The digital attenuator internally pre-attenuates the signal by a certain dB value. When the detected RF signal is too strong, the second control circuit 143 adjusts the digital attenuator to regulate or maintain the output power of the output interface (i.e., the first interface 110). When the signal received by the second interface 120 is too weak, the second control circuit 143 adjusts the digital attenuator to cancel the pre-attenuation in dB, thereby regulating or maintaining the output power of the first interface 110.

[0072] like Figure 6 As shown, in some embodiments, the gain circuit 141 includes a first filter circuit 1411, an amplifier circuit 1412, an adjustment circuit 1413, and a second filter circuit 1414.

[0073] The input terminal of the first filter circuit 1411 is connected to the input side interface of the first interface 110 and the second interface 120. The first filter circuit 1411 is used to perform a first filter on the radio frequency signal. The input terminal of the amplifier circuit 1412 is connected to the output terminal of the first filter circuit 1411, and the output terminal is connected to the detector circuit 142. The amplifier circuit 1412 is used to preset the gain of the radio frequency signal after the first filter. The input terminal of the adjustment circuit 1413 is connected to the output terminal of the amplifier circuit 1412, and the adjustment terminal of the adjustment circuit 1413 is connected to the second control circuit 143. The output terminal of the adjustment circuit 1413 is connected to the output side interface of the first interface 110 and the second interface 120. The adjustment circuit 1413 is used to adjust the gain of the radio frequency signal after the preset gain according to the adjustment signal. The second filter circuit 1414 is connected to the output terminal of the adjustment circuit 1413 and is used to perform a second filter on the radio frequency signal after the gain adjustment.

[0074] In this embodiment, antenna 200 serves as a receiving antenna. The input terminal of the first filter circuit 1411 is connected to the first interface 110, which serves as the input-side interface connected to antenna 200. The second interface 120 serves as the output-side interface connected to the receiver of the wireless audio system. The first filter circuit 1411 is primarily used to filter out high-frequency spurious signals (signals above 1 GHz). The amplifier circuit 1412 is, for example, a low-noise amplifier, primarily amplifying the useful radio frequency signal. The adjustment circuit 1413 is, for example, a digital attenuator, primarily attenuating the radio frequency signal and used to control the gain of the radio frequency signal. The second filter circuit 1414 is primarily used to filter out low-frequency spurious signals (signals below 470 MHz).

[0075] The radio frequency signal received by antenna 200 reaches the first filter circuit 1411 and simultaneously the detector circuit 142. The detector circuit 142 demodulates the high-frequency signal into a DC signal, which is then sent to the ADC port of the second control circuit 143. The digital attenuator internally pre-attenuates the signal by a certain dB value. When the detected radio frequency signal is too strong, the second control circuit 143 adjusts the digital attenuator to maintain the output power of the second interface 120. When the signal received by the first interface 110 is too weak, the second control circuit 143 adjusts the digital attenuator to cancel the pre-attenuation in dB, maintaining the output power of the second interface 120.

[0076] like Figure 7As shown, in some embodiments, the antenna gain switching circuit 100 further includes a first button 180, which is connected to the first control circuit 170. The first button 180 is used to output a first button 180 signal according to user operation. The first control circuit 170 is also used to control the switching circuit 160 to disconnect the passive channel 130 and connect the active gain channel 140 according to the first button 180 signal, or to connect the passive channel 130 and disconnect the active gain channel 140.

[0077] This embodiment provides a method for a user to select whether the antenna 200 operates in an active or passive state. For example, when a power signal is received at the second interface 120, the user can operate the first button 180 to select whether the antenna 200 operates in an active or passive state. When no power signal is received at the second interface 120, the user can operate the first button 180 to select whether the antenna 200 operates in a passive state, thus avoiding entering an active mode and becoming inoperable.

[0078] like Figure 8 As shown, in some embodiments, the antenna gain switching circuit 100 further includes a second button 190, which is connected to the second control circuit 143. The second button 190 is used to output a second button 190 signal according to user operation; the second control circuit 143 is also used to adjust or fix the adjustment signal according to the second button 190 signal.

[0079] This embodiment provides a user-operable adjustment or fixed adjustment signal, and the second control circuit 143 controls the adjustment circuit 1413 to adjust the gain of the radio frequency signal according to the adjustment signal.

[0080] In some embodiments, the second control circuit 143 and the first control circuit 170 are integrated into the same control chip. In other embodiments, the second control circuit 143 and the first control circuit 170 may be different control chips and communicate with each other.

[0081] like Figure 9 As shown, in some embodiments, the first control circuit 170 includes a transistor Q1, a first resistor R1 and a second resistor R2, and the second control circuit 143 includes a control chip.

[0082] The first end of the first resistor R1 is connected to the output terminal of the power supply circuit 150. The second end of the first resistor R1 is connected to the first end of the second resistor R2 and the base of the transistor Q1. The second end of the second resistor R2 is connected to the control pin of the control chip. The collector of the transistor Q1 is connected to the switching circuit 160. The emitter of the transistor Q1 is grounded.

[0083] When the power supply circuit 150 has no power supply signal output, the passive channel 130 is turned on and the active gain channel 140 is turned off; when the power supply circuit 150 has a power supply signal output, the control chip after power-on controls the conduction of the transistor Q1 to control the power-on of the switching circuit 160, thereby controlling the passive channel 130 to turn off and the active gain channel 140 to turn on.

[0084] like Figure 10 As shown, in some embodiments, the switching circuit 160 includes a drive module 162, a first switch module 163, and a second switch module 164.

[0085] The drive module 162 is connected to the first control circuit 170 and the power supply circuit 150; the first switch module 163 includes a first control part K1 / K4, a first normally closed switch K2 / K3 and a second normally closed switch K5 / K6. The first control part K1 / K4 of the first switch module 163 is connected to the drive module 162. The first normally closed switch K2 / K3 and the second normally closed switch K5 / K6 are connected in series between the first interface 110 and the second interface 120 to form a passive channel 130; the second switch module 164 includes a second The control section K9 / K12, the first normally open switch K7 / K8, and the second normally open switch K10 / K11 are connected. The second control section K9 / K12 is connected to the drive module 162. The moving contact K7 of the first normally open switch K7 / K8 is connected to the first interface 110. The moving contact K10 of the second normally open switch K10 / K11 is connected to the second interface 120. The active gain channel 140 is connected between the normally open contact K8 of the first normally open switch K7 / K8 and the normally open contact K11 of the second normally open switch K10 / K11.

[0086] For example, the first switch module 163 and the second switch module 164 are relays, and the first control part K1 / K4 and the second control part K9 / K12 are relay coils, respectively. See also... Figure 9 In the previous embodiment, the first control circuit 170 serves as the driving module 162 in this embodiment. When the power supply circuit 150 has no power supply signal output, the relay coil is not energized, and the first normally closed switch K2 / K3 and the second normally closed switch K5 / K6 are connected, the passive channel 130 is connected, the active gain channel 140 is disconnected, and the antenna 200 operates in a passive state. When the power supply circuit 150 has a power supply signal output, the relay coil is energized, and the first normally open switch K7 / K8, the second normally open switch K10 / K11 and the active gain channel 140 are connected, the active gain channel 140 is connected, the passive channel 130 is disconnected, and the antenna 200 operates in an active gain state.

[0087] like Figure 9As shown, in some embodiments, the first switch module 163 and the second switch module 164 share the same control section A1 / A5, the first normally closed switch A2 / A3 and the first normally open switch A3 / A4 share the same moving contact A3, and the second normally closed switch A6 / A7 and the second normally open switch A7 / A8 share the same moving contact A7. That is, the first switch module 163 and the second switch module 164 are integrated into the same relay.

[0088] Secondly, embodiments of this application also provide an antenna 200, including a passive antenna 200, a circuit board, and an antenna gain switching circuit 100 as described in any of the above embodiments. Integrating the passive antenna 200, the circuit board, and the antenna gain switching circuit 100 into a single module facilitates use; furthermore, this antenna 200 can function as either a transmitting antenna 200 or a receiving antenna 200.

[0089] Thirdly, embodiments of this application also provide a wireless audio system, including an antenna 200 and a receiver as described in any of the above embodiments, with the antenna 200 connected to the receiver; or an antenna 200 and a transmitter as described in any of the above embodiments, with the antenna 200 connected to the transmitter.

[0090] The antenna 200 described above can be used in wireless audio systems as a wireless receiving device or as a wireless transmitting device.

[0091] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. An antenna gain switching circuit for a wireless audio system, characterized in that, The antenna gain switching circuit includes: The first interface is used to connect a passive antenna; The second interface is used to connect to the receiver of the wireless audio system to output radio frequency signals to the receiver, or to connect to the transmitter of the wireless audio system to receive radio frequency signals output by the transmitter. A passive channel is connected between the first interface and the second interface for directly transmitting radio frequency signals between the first interface and the second interface; An active gain channel is connected between the first interface and the second interface. The passive channel and the active gain channel are selectively turned on. The active gain channel is used to gain the radio frequency signal between the first interface and the second interface based on the feed signal accessed by the second interface.

2. The antenna gain switching circuit as described in claim 1, characterized in that, Also includes: A power supply circuit, connected to the second interface, is used to output a power supply signal based on the power supply signal; A switching circuit is connected to the first interface, the second interface, the passive channel, the passive channel, and the power supply circuit. The switching circuit is used to turn on the passive channel and turn off the active gain channel when the power supply signal is not received. A first control circuit is connected to the power supply circuit and the switching circuit. The first control circuit is used to control the switching circuit to disconnect the passive channel and connect the active gain channel based on the power supply signal.

3. The antenna gain switching circuit as described in claim 2, characterized in that, The active gain channel includes: A gain circuit is connected to the power supply circuit and to the first interface and the second interface through the switching circuit. The gain circuit is used to increase the radio frequency signal between the first interface and the second interface based on the power supply signal.

4. The antenna gain switching circuit as described in claim 3, characterized in that, The active gain channel also includes: A detection circuit, connected to the gain circuit, is used to detect the gain of the RF signal after gain adjustment and output a detection signal corresponding to the gain. The second control circuit is connected to the detection circuit, the power supply circuit and the gain circuit, and is used to adjust the gain of the gain circuit to the radio frequency signal according to the detection signal output adjustment signal.

5. The antenna gain switching circuit as described in claim 4, characterized in that, The gain circuit includes: A first filtering circuit, the input terminal of which is connected to the first interface and the second interface as the input side, is used to perform a first filtering on the radio frequency signal. An amplifier circuit, wherein the input terminal of the amplifier circuit is connected to the output terminal of the first filter circuit, and the output terminal is connected to the detector circuit, and the amplifier circuit is used to preset the gain of the radio frequency signal after the first filter. An adjustment circuit is provided, wherein the input terminal of the adjustment circuit is connected to the output terminal of the amplifier circuit, the adjustment terminal of the adjustment circuit is connected to the second control circuit, and the output terminal of the adjustment circuit is connected to the output side of the first interface and the second interface. The adjustment circuit is used to adjust the gain of the radio frequency signal after the preset gain according to the adjustment signal.

6. The antenna gain switching circuit as described in claim 5, characterized in that, The gain circuit also includes: The second filter circuit is connected to the output of the adjustment circuit and is used to perform a second filter on the gain-adjusted radio frequency signal.

7. The antenna gain switching circuit as described in claim 2, characterized in that, It also includes a first button, which is connected to the first control circuit and is used to output a first button signal according to user operation. The first control circuit is further configured to control the switching circuit to disconnect the passive channel and connect the active gain channel, or connect the passive channel and disconnect the active gain channel, according to the first key signal.

8. The antenna gain switching circuit as described in claim 4, characterized in that, It also includes a second button, which is connected to the second control circuit and is used to output a second button signal according to user operation; The second control circuit is also used to adjust or fix the adjustment signal according to the second key signal.

9. The antenna gain switching circuit as described in claim 4, characterized in that, The second control circuit and the first control circuit are integrated into the same control chip.

10. The antenna gain switching circuit as described in claim 4, characterized in that, The first control circuit includes a transistor, a first resistor, and a second resistor; the second control circuit includes a control chip. The first end of the first resistor is connected to the output terminal of the power supply circuit, the second end of the first resistor is connected to the first end of the second resistor and the base of the transistor, the second end of the second resistor is connected to the control pin of the control chip, the collector of the transistor is connected to the switching circuit, and the emitter of the transistor is grounded.

11. The antenna gain switching circuit according to any one of claims 2 to 9, characterized in that, The switching circuit includes: The drive module is connected to the first control circuit and the power supply circuit; The first switch module includes a first control part, a first normally closed switch and a second normally closed switch. The first control part is connected to the drive module. The first normally closed switch and the second normally closed switch are connected in series between the first interface and the second interface to form the passive channel. The second switch module includes a second control section, a first normally open switch, and a second normally open switch. The second control section is connected to the drive module. The moving contact of the first normally open switch is connected to the first interface, and the moving contact of the second normally open switch is connected to the second interface. The active gain channel is connected between the normally open contact of the first normally open switch and the normally open contact of the second normally open switch.

12. The antenna gain switching circuit as described in claim 11, characterized in that, The first control section and the second control section are the same. The first normally closed switch and the first normally open switch share the same moving contact, and the second normally closed switch and the second normally open switch share the same moving contact.

13. An antenna, characterized in that, It includes a passive antenna, a circuit board, and an antenna gain switching circuit as described in any one of claims 1 to 12.

14. A wireless audio system, characterized in that, Includes the antenna and receiver as described in claim 13, wherein the antenna is connected to the receiver; or includes the antenna and transmitter as described in claim 13, wherein the antenna is connected to the transmitter.

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