Signal processing circuit, vehicle-mounted voice system and vehicle

Abstract

The utility model provides a signal processing circuit, a vehicle-mounted display screen and a vehicle. The signal processing circuit is applied to a vehicle-mounted voice system. The signal processing circuit comprises a first adjusting module and a second adjusting module; the first adjusting module is respectively connected with the pickup circuit, the host and the Internet of Vehicles box, and the first adjusting module is used for accessing an audio signal and increasing the voltage and amplitude of the audio signal; the second adjusting module is connected with the first adjusting module and the vehicle networking box, and the second adjusting module is used for accessing the increased audio signal, reducing the voltage and the amplitude of the audio signal, and outputting the voltage and the amplitude of the audio signal to the vehicle networking box. The signal processing circuit can convert low-voltage audio signals into high-voltage audio signals through the first adjusting module, so that the signal-to-noise ratio and the anti-interference capability of the audio signals are improved, the loss of the audio signals in long-distance transmission is reduced, meanwhile, the audio signals can be attenuated through the second adjusting module, and the transmission efficiency of the audio signals is improved. Therefore, the pickup reliability of the vehicle-mounted voice system is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of vehicles, and more specifically, to a signal processing circuit, an in-vehicle voice system, and a vehicle. Background Art

[0002] With the rapid development of intelligent vehicles, in-vehicle voice systems have become increasingly advanced. Currently, an in-vehicle voice system generally consists of a sound pickup circuit, a Telematics control Box (T-BOX), and a Head Unit System (HUT). The sound pickup circuit collects audio signals inside the vehicle and transmits them to the T-BOX via the HUT. The T-BOX processes these audio signals and sends them to the cloud to complete the voice interaction function.

[0003] However, the installation positions of the T-BOX and the HUT in the vehicle are relatively far apart. The audio signals collected by the sound pickup circuit may suffer signal loss during long-distance transmission, resulting in problems such as low signal transmission reliability and quality, and further affecting the sound pickup reliability of the in-vehicle voice system. Summary of the Utility Model

[0004] The present application provides a signal processing circuit, an in-vehicle voice system, and a vehicle, aiming to solve the problem that audio signals may suffer signal loss during long-distance transmission, resulting in low signal transmission reliability and quality, and further affecting the sound pickup reliability.

[0005] In a first aspect, a signal processing circuit is provided, which is applied to an in-vehicle voice system. The in-vehicle voice system includes a sound pickup circuit, a host, and a Telematics control box. The sound pickup circuit is used to collect audio signals. The signal processing circuit includes a first adjustment module and a second adjustment module. The first adjustment module is respectively connected to the sound pickup circuit, the host, and the Telematics control box. The first adjustment module is used to access the audio signals and increase the voltage and amplitude of the audio signals. The second adjustment module is respectively connected to the first adjustment module and the Telematics control box. The second adjustment module is used to access the increased audio signals and reduce the voltage and amplitude of the audio signals and output them to the Telematics control box.

[0006] In the above technical solution, the signal processing circuit can correspondingly increase the voltage of the audio signal through the first adjustment module, so as to convert the low-voltage audio signal into a high-voltage audio signal, improve the signal-to-noise ratio and anti-interference ability of the audio signal, and the loss of the high-voltage audio signal during long-distance transmission is relatively low, so as to ensure the intensity of the audio signal, thereby improving the reliability and accuracy of the audio signal received by the vehicle networking box. At the same time, the first adjustment module can also increase the amplitude of the audio signal to improve the quality and signal intensity of the audio signal. When the amplitude of the audio signal is large, the signal-to-noise ratio of the audio signal can be further improved. In this way, the low-voltage audio signal is converted into a high-voltage audio signal through the first adjustment module, reducing the signal loss of the audio signal during long-distance transmission, improving the signal-to-noise ratio, anti-interference ability and signal quality of the audio signal, thereby ensuring the transmission reliability and accuracy of the audio signal, so as to ensure the reliability of sound pickup. Then, the second adjustment module in the vehicle networking box reduces the voltage and amplitude of the audio signal output by the first adjustment module and outputs it to the control chip in the vehicle networking box, so as to avoid the problem that the voltage fluctuation caused by the loss of the host power supply exceeds the tolerance range of the control chip in the vehicle networking box, resulting in overloading or damage of the control chip in the vehicle networking box, and further ensuring the sound pickup reliability of the in-vehicle voice system.

[0007] In combination with the first aspect, in some possible implementation manners, the first adjustment module includes a bias unit. The first end of the bias unit is connected to the host and the vehicle networking box, and the second end of the bias unit is connected to the sound pickup circuit for accessing the audio signal. Among them, the host and the vehicle networking box are used to provide a bias voltage to the audio signal through the bias unit.

[0008] In the above technical solution, the host and the vehicle networking box providing a bias voltage to the audio signal through the bias unit can increase the voltage and amplitude of the audio signal, so as to reduce the signal loss of the audio signal during long-distance transmission, improve the signal-to-noise ratio and anti-interference ability of the audio signal, thereby ensuring the transmission reliability and accuracy of the audio signal, so as to ensure the reliability of sound pickup.

[0009] In combination with the first aspect and the above implementation manners, in some possible implementation manners, the bias unit includes a first resistor, a second resistor, a third resistor and a fourth resistor; one end of the first resistor and one end of the second resistor are connected to the first end of the sound pickup circuit, the other end of the first resistor and the other end of the second resistor are connected to the host and the vehicle networking box, one end of the third resistor and one end of the fourth resistor are connected to the second end of the sound pickup circuit, and the other end of the third resistor and the other end of the fourth resistor are grounded.

[0010] In the above technical solution, the host and the vehicle networking box in the present application are simultaneously connected to the other ends of the first resistor and the second resistor, so that the host and the vehicle networking box provide a bias voltage for the audio signal to achieve dual power supply, which can avoid the problem that the audio signal is interfered and generates noise when the power supply of the host is accidentally lost, so as to ensure the reliability of the audio signal, and further ensure the sound pickup reliability and stability of the vehicle-mounted voice system.

[0011] Combined with the first aspect and the above implementation manner, in some possible implementation manners, the first adjustment module further includes a filtering unit and a connector unit; the first end of the filtering unit is connected to the third end of the biasing unit, and the second end of the filtering unit is connected to the fourth end of the biasing unit; the first end of the connector unit is connected to the third end of the filtering unit, the second end of the connector unit is connected to the fourth end of the filtering unit, the third end of the connector unit is connected to the first end of the second adjustment module, and the fourth end of the connector unit is connected to the second end of the second adjustment module.

[0012] In the above technical solution, the filtering unit can isolate the DC bias in the audio signal and then output it to the connector unit, so as to avoid the problem that the DC bias may cause the audio signal received by the connector unit to be distorted, and further affect the normal operation of the subsequent circuit. In severe cases, it may even damage the sensitive components in the subsequent circuit. Then, the connector unit transmits the audio signal to the second adjustment module to improve the effective transmission between the first adjustment module and the second adjustment module, thereby ensuring the working reliability of the first adjustment module and the transmission reliability of the audio signal.

[0013] Combined with the first aspect and the above implementation manner, in some possible implementation manners, the filtering unit includes a first inductor, a second inductor, a first capacitor, a second capacitor, a third capacitor, and a fourth capacitor; one end of the first inductor is connected to the first plate of the first capacitor and the third end of the biasing unit, the other end of the first inductor is connected to the first plate of the second capacitor and the first end of the connector unit, one end of the second inductor is connected to the first plate of the third capacitor and the fourth end of the biasing unit, the other end of the second inductor is connected to the first plate of the fourth capacitor and the second end of the connector unit, and the second plates of the first capacitor, the second capacitor, the third capacitor, and the fourth capacitor are respectively grounded.

[0014] Combined with the first aspect and the above implementation manner, in some possible implementation manners, the vehicle networking box includes a control chip; the second adjustment module includes a voltage regulation unit, and the voltage regulation unit is respectively connected to the first adjustment module and the control chip. The voltage regulation unit is used to access the increased audio signal and reduce the voltage and amplitude of the audio signal and output it to the control chip.

[0015] In the above technical solution, the voltage regulating unit can access the increased audio signal, reduce the voltage and amplitude of the audio signal, and output it to the control chip, so that the voltage and amplitude of the audio signal match the operating voltage of the control chip, avoiding the problem that the voltage fluctuation caused by the loss of the host power supply exceeds the tolerance range of the control chip, resulting in the overload or damage of the control chip, and further ensuring the voice pickup reliability of the vehicle-mounted voice system.

[0016] Combined with the first aspect and the above implementation manners, in some possible implementation manners, the voltage regulating unit includes a fifth resistor and a sixth resistor; one end of the fifth resistor and one end of the sixth resistor are connected to the first end of the first adjustment module and the first end of the control chip, and the other end of the fifth resistor and the other end of the sixth resistor are grounded.

[0017] In the above technical solution, the voltage regulating unit can release the voltage of the audio signal to the ground through the fifth resistor and the sixth resistor, so as to reduce the voltage and amplitude of the audio signal transmitted by the first adjustment module, make the adjusted audio signal match the operating voltage of the control chip, avoid the problem that the voltage fluctuation caused by the loss of the host power supply exceeds the tolerance range of the control chip, resulting in the overload or damage of the control chip, and further ensure the voice pickup reliability of the vehicle-mounted voice system.

[0018] Combined with the first aspect and the above implementation manners, in some possible implementation manners, the voltage regulating unit includes a seventh resistor, one end of the seventh resistor is connected to the first end of the first adjustment module and the first end of the control chip, and the other end of the seventh resistor is connected to the second end of the first adjustment module and the second end of the control chip.

[0019] In the above technical solution, the voltage regulating unit can release the voltage of the audio signal to the first end and the second end of the control chip through the seventh resistor, so as to reduce the voltage and amplitude of the audio signal transmitted by the first adjustment module, make the adjusted audio signal match the operating voltage of the control chip, avoid the problem that the voltage fluctuation caused by the loss of the host power supply exceeds the tolerance range of the control chip, resulting in the overload or damage of the control chip, and further ensure the voice pickup reliability of the vehicle-mounted voice system.

[0020] In a second aspect, the present application provides a vehicle-mounted voice system, including a voice pickup circuit, a host, a vehicle networking box, and the signal processing circuit according to any optional manner of the first aspect.

[0021] In a third aspect, the present application provides a vehicle, including a vehicle body and the vehicle-mounted voice system according to the second aspect, and the vehicle-mounted voice system is mounted on the vehicle body. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic diagram of the module structure of a vehicle-mounted voice system provided by an embodiment of the present application;

[0023] Figure 2 It is a schematic diagram of the module structure of another vehicle-mounted voice system provided by an embodiment of the present application;

[0024] Figure 3 It is a schematic diagram of the module structure of yet another vehicle-mounted voice system provided by an embodiment of the present application;

[0025] Figure 4 It is a schematic diagram of the circuit structure of a vehicle-mounted voice system provided by an embodiment of the present application;

[0026] Figure 5 It is a schematic diagram of the circuit structure of a sound pickup circuit provided by the related art;

[0027] Figure 6 It is a schematic diagram of the circuit structure of another vehicle-mounted voice system provided by an embodiment of the present application;

[0028] Figure 7 It is a schematic diagram of the circuit structure of yet another vehicle-mounted voice system provided by an embodiment of the present application;

[0029] Figure 8 It is a schematic diagram of the circuit structure of still another vehicle-mounted voice system provided by an embodiment of the present application;

[0030] Figure 9 It is a schematic diagram of the module structure of still another vehicle-mounted voice system provided by an embodiment of the present application;

[0031] Figure 10 It is a schematic diagram of the circuit structure of still another vehicle-mounted voice system provided by an embodiment of the present application;

[0032] Figure 11 It is a schematic diagram of the circuit structure of still another vehicle-mounted voice system provided by an embodiment of the present application;

[0033] Figure 12 It is a schematic diagram of the circuit structure of still another vehicle-mounted voice system provided by an embodiment of the present application.

[0034] Among them, the reference numerals in the figure:

[0035] 1', sound pickup circuit; 11', sound pickup microphone; 1, sound pickup circuit; 2, host; 3, vehicle networking box; 4, signal processing circuit; 41, first adjustment module; 411, bias unit; 412, filtering unit; 413, connector unit; 42, second adjustment module; 421, voltage regulation unit;

[0036] R1, the first resistor; R2, the second resistor; R3, the third resistor; R4, the fourth resistor; R5, the fifth resistor; R6, the sixth resistor; R7, the seventh resistor; R8, the eighth resistor; R9, the ninth resistor; R10, the tenth resistor; R11, the eleventh resistor; MIC+, the first audio signal; MIC-, the second audio signal; L1, the first inductor; L2, the second inductor; C1, the first capacitor; C2, the second capacitor; C3, the third capacitor; C4, the fourth capacitor; C5, the fifth capacitor; C6, the sixth capacitor; D, the diode. Detailed implementation manners

[0037] The technical solutions in the present application will be clearly and elaborately described below in conjunction with the accompanying drawings. Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B: "and / or" in the text is only a description of the association relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality of" means two or more than two.

[0038] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0039] With the continuous development of intelligent vehicles, the functions that a vehicle can achieve (i.e., the systems integrated in the vehicle) are also increasing. For example, an in-vehicle voice system for voice interaction, an Antilock Brake System (ABS) for functions such as emergency stops when the vehicle is in an emergency state, a Parking Deceleration Control (CDP) for deceleration, and so on are integrated in the vehicle. Among them, the in-vehicle voice system usually consists of a pickup circuit, an HUT, and a T-BOX. The HUT is connected to the T-BOX through in-vehicle Ethernet. The pickup circuit collects the audio signals inside the vehicle and transmits the collected audio signals to the T-BOX via the HUT. The T-BOX then processes these audio signals and sends them to the cloud to complete the voice interaction function.

[0040] To save the manufacturing cost of vehicles, in some vehicles, the T-BOX and the HUT share the same sound pickup circuit. In testing or debugging scenarios, the audio signals collected by the sound pickup circuit will be used by the HUT and not sent to the T-BOX. When the T-BOX uses the sound pickup circuit, the audio signals collected by the sound pickup circuit will be transmitted to the T-BOX via the HUT, that is, at this time, the HUT only plays the role of relaying signals and will not process the audio signals. However, the installation positions of the T-BOX and the HUT in the vehicle are relatively far apart. The microphone (MIC) in the sound pickup circuit usually works in a low-voltage environment, that is, the microphone is usually designed to capture sound signals and convert them into weak audio signals (i.e., electrical signals). These audio signals are usually in the millivolt (mV) range and belong to the low-voltage category, resulting in possible signal loss during long-distance transmission of the audio signals, leading to problems of low signal transmission reliability and quality, and further affecting the sound pickup reliability of the in-vehicle voice system.

[0041] Therefore, the present application provides a signal processing circuit, an in-vehicle voice system, and a vehicle. The signal processing circuit can convert low-voltage audio signals into high voltage through a first adjustment module to improve the signal-to-noise ratio and anti-interference ability of the audio signals, thereby reducing the loss of audio signals during long-distance transmission. At the same time, it can also attenuate the audio signals through a second adjustment module to ensure the sound pickup reliability of the in-vehicle voice system.

[0042] The following will provide an exemplary introduction to the signal processing circuit, the in-vehicle voice system, and the vehicle provided by the present application with reference to the accompanying drawings. Here, it is worth noting that the in-vehicle voice system provided by the present application can be applied to various intelligent vehicles, and the present application does not make specific limitations in this regard.

[0043] An embodiment of the present application provides a vehicle, which includes a vehicle body and an in-vehicle voice system. The in-vehicle voice system is mounted on the vehicle body and is used to extract audio signals inside the vehicle body and enable the vehicle to implement a voice interaction function based on the audio signals. The voice interaction function here can include telephone communication, voice navigation, and music multimedia interaction, etc. The vehicle may also include a CDP, an ABS, etc. The specific systems inside the vehicle can be set according to actual needs, and the present application does not make specific limitations in this regard.

[0044] Among them, in order to enable the in-vehicle voice system to extract and process the audio signals inside the vehicle body so that the vehicle can implement a voice interaction function based on the audio signals, in one example, such as Figure 1As shown, the in-vehicle voice system provided by the present application may include a sound pickup circuit 1, a host 2, and a vehicle networking box 3. When the in-vehicle voice system operates, the sound pickup circuit 1 collects audio signals inside the vehicle, and transmits the collected audio signals to the vehicle networking box 3 via the host 2. The vehicle networking box 3 then processes these audio signals and sends them to the cloud to complete the voice interaction function.

[0045] The installation positions of the host 2 and the vehicle networking box 3 in the vehicle are far apart, and based on different vehicle models, the sound pickup circuit 1 is also correspondingly arranged at different positions. In order to improve the transmission reliability of the audio signal, in one example, the in-vehicle voice system may further include a signal processing circuit. The signal processing circuit is respectively connected to the sound pickup circuit 1, the host 2, and the vehicle networking box 3. The signal processing circuit can improve the quality and transmission reliability of the audio signal, thereby ensuring the sound pickup reliability of the in-vehicle voice system to improve the user experience effect. In one example, as Figure 2 shown, the signal processing circuit 4 may include a first adjustment module 41 and a second adjustment module 42. The first adjustment module 41 is respectively connected to the sound pickup circuit 1, the host 2, and the vehicle networking box 3. The second adjustment module 42 is respectively connected to the first adjustment module 41 and the vehicle networking box 3.

[0046] Among them, the first adjustment module 41 is used to access the audio signal of the sound pickup circuit 1 and correspondingly increase the voltage of the audio signal to convert the low-voltage audio signal into a high-voltage audio signal, so as to improve the signal-to-noise ratio and anti-interference ability of the audio signal, and the loss of the high-voltage audio signal during long-distance transmission is relatively low to ensure the intensity of the audio signal, thereby improving the reliability and accuracy of the audio signal received by the vehicle networking box 3. At the same time, the first adjustment module 41 can also increase the amplitude of the audio signal to improve the quality and signal intensity of the audio signal. When the amplitude of the audio signal is large, the signal-to-noise ratio of the audio signal can be further improved. In this way, the first adjustment module 41 converts the low-voltage audio signal into a high-voltage audio signal, reducing the signal loss of the audio signal during long-distance transmission, improving the signal-to-noise ratio, anti-interference ability, and signal quality of the audio signal, thereby ensuring the transmission reliability and accuracy of the audio signal to ensure the sound pickup reliability.

[0047] In one example, the first adjustment module 41 can increase the voltage and amplitude of the audio signal by increasing the bias voltage. Exemplarily, as Figure 3As shown, the first adjustment module 41 may include a bias unit 411. One end of the bias unit 411 is connected to the host 2 and the vehicle networking box 3, and the other end of the bias unit 411 is connected to the sound pickup circuit 1 for accessing an audio signal. In this example, the host 2 and the vehicle networking box 3 may provide a bias voltage to the audio signal via the bias unit 411. Here, it is worth noting that the audio signal output by the sound pickup circuit 1 includes a first audio signal MIC+ and a second audio signal MIC-, that is, the sound pickup circuit 1 has two output terminals. One output terminal is a signal terminal for outputting the first audio signal MIC+, and the other is a ground terminal for outputting the second audio signal MIC-. The host 2 and the vehicle networking box 3 may provide a bias voltage to the first audio signal MIC+ and the second audio signal MIC- via the bias unit 411. In this way, by setting the bias unit 411, the voltage and amplitude of the first audio signal MIC+ and the second audio signal MIC- can be increased to reduce the signal loss of the first audio signal MIC+ and the second audio signal MIC- during long-distance transmission, improve the signal-to-noise ratio and anti-interference ability of the first audio signal MIC+ and the second audio signal MIC-, thereby ensuring the transmission reliability and accuracy of the first audio signal MIC+ and the second audio signal MIC- to ensure the problem of sound pickup reliability.

[0048] In one example, as Figure 4 shown, the bias unit 411 includes a first resistor R1, a second resistor R2, a third resistor R3, and a fourth resistor R4. One end of the first resistor R1 and one end of the second resistor R2 are connected to the first end of the sound pickup circuit 1, the other end of the first resistor R1 and the other end of the second resistor R2 are connected to the host 2 and the vehicle networking box 3, one end of the third resistor R3 and one end of the fourth resistor R4 are connected to the second end of the sound pickup circuit 1, and the other end of the third resistor R3 and the other end of the fourth resistor R4 are grounded.

[0049] Here, it is worth noting that, as Figure 5As shown, the sound pickup circuit 1' in the related art includes a sound pickup microphone 11', an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11. One end of the sound pickup microphone 11' is respectively connected to one end of the eighth resistor R8 and one end of the ninth resistor R9, that is, one end of the eighth resistor R8 and one end of the ninth resistor R9 are connected to the first audio signal MIC+. The other end of the eighth resistor R8 is connected to the vehicle networking box 3, and the other end of the ninth resistor R9 is connected to the host 2. The other end of the sound pickup microphone 11' is respectively connected to one end of the tenth resistor R10 and one end of the eleventh resistor R11, that is, one end of the tenth resistor R10 and one end of the eleventh resistor R11 are connected to the second audio signal MIC-. The other end of the tenth resistor R10 and the other end of the eleventh resistor R11 are respectively grounded. In this example, the vehicle networking box 3 and the host 2 respectively process the first audio signal MIC+ through the eighth resistor R8 and the ninth resistor R9. However, when the power supply of the host 2 is accidentally lost, the ninth resistor R9 will be equivalently disconnected, resulting in the matching resistor on the side of the first audio signal MIC+ changing from the parallel connection of the 680 Ω (ohm) provided by the eighth resistor R8 and the ninth resistor R9 to a single 680 Ω provided by the eighth resistor R8, causing the audio signal to be interfered, resulting in problems such as abnormal sound and noise, and further affecting the working stability of the sound pickup circuit 1'.

[0050] Therefore, the present application can realize dual power supply for the sound pickup circuit 1 by the host 2 and the vehicle networking box 3, that is, the host 2 and the vehicle networking box 3 in the present application are simultaneously connected to the other end of the first resistor R1 and the other end of the second resistor R2, so that the host 2 and the vehicle networking box 3 provide a bias voltage for the audio signal to achieve dual power supply. Among them, the bias voltage at the host 2 end always exists, and the bias voltage at the vehicle networking box 3 end only exists when the vehicle makes an emergency call. Specifically, when the power supply of the host 2 is normal and the emergency call function is started at the same time, the bias voltage of the audio signal is provided by the host 2 and the vehicle networking box 3 at the same time. When the power supply of the host 2 is accidentally lost, the vehicle networking box 3 can use the internal backup battery so that the vehicle can start the emergency call function. In this way, by dual power supply for the sound pickup circuit 1 by the host 2 and the vehicle networking box 3, it is possible to avoid the audio signal being interfered when the power supply of the host 2 is accidentally lost, resulting in problems such as abnormal sound and noise, to ensure the reliability of the audio signal, and further ensure the sound pickup reliability and stability of the in-vehicle voice system.

[0051] Under this example, the resistance values of the first resistor R1 and the second resistor R2 can be set to 680 Ω. The host 2 and the vehicle networking box 3 can increase the voltage and amplitude of the first audio signal MIC+ and the second audio signal MIC- through the first resistor R1 and the second resistor R2. Exemplarily, the host 2 and the vehicle networking box 3 simultaneously provide a relatively high bias voltage, such as a bias voltage of 8V±10%, to the first audio signal MIC+ and the second audio signal MIC- through the bias unit 411, so as to increase the DC bias voltage of the first audio signal MIC+ to 6V, and at the same time set the amplitude of the first audio signal MIC+ to ±2V, that is, the first adjustment module 41 can increase the first audio signal MIC+ to 8V, so as to convert the low-voltage first audio signal MIC+ into a high-voltage audio signal, thereby improving the signal-to-noise ratio and anti-interference ability of the first audio signal MIC+, and the loss of the high-voltage audio signal during long-distance transmission is relatively low, so as to ensure the intensity of the audio signal, thereby improving the reliability and accuracy of the audio signal received by the vehicle networking box 3. Increase the DC bias voltage of the second audio signal MIC- to 2V, and at the same time set the amplitude of the second audio signal MIC- to ±2V, so as to improve the signal-to-noise ratio and anti-interference ability of the second audio signal MIC-, thereby ensuring the transmission reliability and accuracy of the first audio signal MIC+ and the second audio signal MIC-, so as to ensure the reliability of sound pickup.

[0052] To avoid the reverse injection of the bias voltage and thus damage the hardware circuits in the host 2 and the vehicle networking box 3. Optionally, as Figure 6 shown, the first adjustment module 41 may further include a diode D. The positive electrode of the diode D is connected to the other end of the first resistor R1 and the other end of the second resistor R2, and the negative electrode of the diode D is connected to the host 2 and the vehicle networking box 3, avoiding the problem that the reverse injection of the bias voltage damages the hardware circuits in the host 2 and the vehicle networking box 3, so as to ensure the power supply stability of the host 2 and the vehicle networking box 3.

[0053] In one example, as Figure 7 shown, the first adjustment module 41 may further include a filtering unit 412 and a connector unit 413. The first end of the filtering unit 412 is connected to the third end of the bias unit 411, the second end of the filtering unit 412 is connected to the fourth end of the bias unit 411, the first end of the connector unit 413 is connected to the third end of the filtering unit 412, the second end of the connector unit 413 is connected to the fourth end of the filtering unit 412, the third end of the connector unit 413 is connected to the first end of the second adjustment module 42, and the fourth end of the connector unit 413 is connected to the second end of the second adjustment module 42.

[0054] In this example, the audio signal output by the biasing unit 411 will be transmitted to the second adjustment module 42 via the filtering unit 412 and the connector unit 413. Since the connector unit 413 can usually only process AC signals and is sensitive to DC signals, the DC signal in the audio signal may cause the connector unit 413 to be overloaded or damaged. Therefore, the filtering unit 412 can isolate the DC bias in the audio signal and then output it to the connector unit 413 to avoid the problem that the DC bias may cause the distortion of the audio signal received by the connector unit 413, which in turn affects the normal operation of the subsequent circuit. In severe cases, it may even damage the sensitive components in the subsequent circuit. Then, the connector unit 413 transmits the audio signal to the second adjustment module 42 to improve the effective transmission between the first adjustment module 41 and the second adjustment module 42, thereby ensuring the working reliability of the first adjustment module 41 and the transmission reliability of the audio signal.

[0055] Here, it can be understood that the audio signal usually includes a first audio signal MIC+ and a second audio signal MIC-. Therefore, the filtering unit 412 can filter out the DC biases of both the first audio signal MIC+ and the second audio signal MIC- and then transmit them to the connector unit 413.

[0056] Optionally, as Figure 8 shown, the filtering unit 412 may include a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a third capacitor C3, and a fourth capacitor C4. One end of the first inductor L1 is connected to the first plate of the first capacitor C1 and the third terminal of the biasing unit 411. The other end of the first inductor L1 is connected to the first plate of the second capacitor C2 and the first terminal of the connector unit 413. One end of the second inductor L2 is connected to the first plate of the third capacitor C3 and the fourth terminal of the biasing unit 411. The other end of the second inductor L2 is connected to the first plate of the fourth capacitor C4 and the second terminal of the connector unit 413. The second plates of the first capacitor C1, the second capacitor C2, the third capacitor C3, and the fourth capacitor C4 are respectively grounded. In this example, the first inductor L1 is used to isolate the DC bias in the first audio signal MIC+ and then output it to the first terminal of the connector unit 413, and the second inductor L2 is used to isolate the DC bias in the second audio signal MIC- and then output it to the second terminal of the connector unit 413 to ensure the transmission reliability of the audio signal.

[0057] Optionally, the connector unit 413 can be a board-to-board connector. By using a board-to-board connector, the effective transmission of the audio signal between the first adjustment module 41 and the second adjustment module 42 can be ensured. The connector unit 413 can also use other types of board-to-board connectors or circuits. In this regard, the present application does not make specific limitations.

[0058] In summary, the audio signal processed by the bias unit 411, the filtering unit 412, and the connector unit 413 in the first adjustment module 41 is a high-voltage signal, which reduces the loss of the audio signal during long-distance transmission, thereby ensuring the intensity of the audio signal and improving the reliability and accuracy of the audio signal received by the vehicle networking box 3. The vehicle networking box 3 generally includes a control chip 31, and the operating voltage of the control chip 31 is usually a low voltage, while the audio signal output by the first adjustment module 41 is a high-voltage signal. To avoid the problem that the voltage fluctuation caused by the power loss of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31, the second adjustment module 42 provided in this application can access the increased audio signal and reduce the voltage and amplitude of the audio signal and output it to the control chip 31 of the vehicle networking box 3, so as to avoid the problem that the voltage fluctuation caused by the power loss of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31. Here, it is worth noting that the second adjustment module 42 transmits the audio signal inside the vehicle networking box 3.

[0059] In one example, as Figure 9 shown, the second adjustment module 42 may include a voltage regulation unit 421. The voltage regulation unit 421 is respectively connected to the first adjustment module 42 and the control chip 31. The voltage regulation unit 421 is used to access the increased audio signal, and then attenuate and reduce the voltage and amplitude of the audio signal and output it to the control chip 31, so that the voltage and amplitude of the audio signal match the operating voltage of the control chip 31, to avoid the problem that the voltage fluctuation caused by the power loss of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31, and further ensure the pickup reliability of the in-vehicle voice system.

[0060] The voltage regulation unit 421 provided in this application can reduce the voltage and amplitude of the audio signal by means of differential-mode attenuation or common-mode attenuation. In one example, the voltage regulation unit 421 can reduce the voltage and amplitude of the audio signal by means of differential-mode attenuation. As Figure 10 shown, the voltage regulation unit 421 may include a fifth resistor R5 and a sixth resistor R6. One end of the fifth resistor R5 and one end of the sixth resistor R6 are connected to the first end of the first adjustment module 41 (i.e., the third end of the connector unit 413) and the first end of the control chip 31, and the other end of the fifth resistor R5 and the other end of the sixth resistor R6 are grounded. In this example, the voltage regulation unit 421 can release the voltage of the audio signal to the ground through the fifth resistor R5 and the sixth resistor R6, so as to reduce the voltage and amplitude of the audio signal transmitted by the first adjustment module 41, make the adjusted audio signal match the operating voltage of the control chip 31, avoid the problem that the voltage fluctuation caused by the power loss of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31, and further ensure the pickup reliability of the in-vehicle voice system.

[0061] Exemplarily, assume that the control chip 31 in the vehicle networking box 3 uses a codec (Coder-Decoder, CODEC) chip, and the operating voltage of the CODEC chip is 3.3V. Then, the fifth resistor R5 and the sixth resistor R6 can attenuate the audio signal, and the attenuation ratio can be 1 / 3, so that the fifth resistor R5 and the sixth resistor R6 can reduce the voltage of the audio signal to 1.65V and reduce the amplitude of the audio signal to ±0.66V, so that the reduced audio signal can match the operating voltage of the control chip 31, so as to avoid the problem that the voltage fluctuation caused by the loss of power supply of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31, and further ensure the sound pickup reliability of the vehicle-mounted voice system.

[0062] Here, it is worth noting that the attenuation ratio of the voltage regulating unit 421 can be set according to the model and operating voltage of the control chip 31, that is, the resistance values of the fifth resistor R5 and the sixth resistor R6 are correspondingly changed to correspondingly adjust the attenuation ratio, so as to be adapted to different models of the control chip 31. In this regard, the present application does not make specific limitations.

[0063] In one example, exemplarily, the voltage regulating unit 421 can reduce the voltage and amplitude of the audio signal by means of common-mode attenuation, such as Figure 11 As shown, the voltage regulating unit 421 can include a seventh resistor R7. One end of the seventh resistor R7 is connected to the first end of the first adjustment module 41 and the first end of the control chip 31, and the other end of the seventh resistor R7 is connected to the second end of the first adjustment module 41 (i.e., the fourth end of the connector unit 413) and the second end of the control chip 31. In this example, the voltage regulating unit 421 can release the voltage of the audio signal to the first end and the second end of the control chip 31 through the seventh resistor R7, so as to reduce the voltage and amplitude of the audio signal transmitted by the first adjustment module 41, so that the adjusted audio signal matches the operating voltage of the control chip 31, so as to avoid the problem that the voltage fluctuation caused by the loss of power supply of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31, and further ensure the sound pickup reliability of the vehicle-mounted voice system.

[0064] Here, it is worth noting that the attenuation ratio of the voltage regulating unit 421 can be set according to the model and operating voltage of the control chip 31, that is, the resistance value of the seventh resistor R7 is correspondingly changed to correspondingly adjust the attenuation ratio, so as to be adapted to different models of the control chip 31. In this regard, the present application does not make specific limitations.

[0065] In one example, in order to enable the voltage regulating unit 421 to achieve differential-mode attenuation or common-mode attenuation based on different control chips 31, such as Figure 12As shown, the voltage regulation unit 421 may include a fifth resistor R5, a sixth resistor R6, and a seventh resistor R7. When it is necessary to reduce the voltage and amplitude of the audio signal in a differential-mode attenuation manner, the seventh resistor R7 is not soldered, and the fifth resistor R5 and the sixth resistor R6 are soldered to achieve differential-mode attenuation. When it is necessary to reduce the voltage and amplitude of the audio signal in a common-mode attenuation manner, the seventh resistor R7 is soldered, and the fifth resistor R5 and the sixth resistor R6 are not soldered to achieve common-mode attenuation.

[0066] Since the first end and the second end of the control chip 31 have built-in DC biases, the audio signal output by the voltage regulation unit 421 also needs to filter out the DC biases. In one example, as Figure 12 shown, the second adjustment module 42 may further include a fifth capacitor C5 and a sixth capacitor C6. One end of the fifth resistor R5, one end of the sixth resistor R6, and one end of the seventh resistor R7 are connected to the first plate of the fifth capacitor C5. The second plate of the fifth capacitor C5 is connected to the first end of the control chip 31. The other end of the seventh resistor R7 is connected to the first plate of the sixth capacitor C6. The second plate of the sixth capacitor C6 is connected to the second end of the control chip 31. In this example, the fifth capacitor C5 and the sixth capacitor C6 can filter out the DC biases in the first audio signal MIC+ and the second audio signal MIC− to avoid the problem that the DC biases may damage the control chip 31, so as to ensure the working reliability of the second adjustment module 42 and the transmission reliability of the audio signal.

[0067] Optionally, when the control chip 31 in the vehicle networking box 3 uses a CODEC chip, there is an automatic gain algorithm inside the CODEC chip, which can appropriately amplify the amplitude of the audio signal, avoiding the problem that the output volume of the vehicle-mounted voice system is affected after the voltage regulation unit 421 attenuates the audio signal, thereby ensuring the reliability of the output volume of the vehicle-mounted voice system.

[0068] In summary, the signal processing circuit provided by the present application can correspondingly increase the voltage of the audio signal through the first adjustment module 41 to convert the low-voltage audio signal into a high-voltage audio signal, so as to improve the signal-to-noise ratio and anti-interference ability of the audio signal. Moreover, the loss of the high-voltage audio signal during long-distance transmission is relatively low, which can ensure the intensity of the audio signal, thereby improving the reliability and accuracy of the audio signal received by the vehicle networking box 3. At the same time, the first adjustment module 41 can also increase the amplitude of the audio signal to improve the quality and signal intensity of the audio signal. When the amplitude of the audio signal is relatively large, the signal-to-noise ratio of the audio signal can be further improved. In this way, by converting the low-voltage audio signal into a high-voltage audio signal through the first adjustment module 41, the signal loss of the audio signal during long-distance transmission is reduced, and the signal-to-noise ratio, anti-interference ability, and signal quality of the audio signal are improved, thereby ensuring the transmission reliability and accuracy of the audio signal and ensuring the reliability of sound pickup. Then, the second adjustment module 42 in the vehicle networking box 3 attenuates and reduces the voltage and amplitude of the audio signal output by the first adjustment module 41 and outputs it to the control chip 31 of the vehicle networking box 3 to avoid the problem that the voltage fluctuation caused by the loss of power supply of the host 2 exceeds the tolerance range of the control chip 31, resulting in the overload or damage of the control chip 31, and further ensuring the reliability of sound pickup of the in-vehicle voice system.

[0069] Through the description of the above embodiments, those skilled in the art can understand that for the convenience and simplicity of description, only the above division of each functional module is used as an example. In actual applications, the above functions can be allocated to different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above.

[0070] In the embodiments provided by the present application, it should be understood that the disclosed device and method can be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces, and the indirect coupling or communication connection of the device or unit may be in an electrical, mechanical or other form.

[0071] The above content is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present application, and all should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A signal processing circuit, characterized in that: Applied to an in-vehicle voice system, the in-vehicle voice system includes a pickup circuit, a host and an Internet of Vehicles box, the pickup circuit is used to collect audio signals; the signal processing circuit includes: a first regulating module, connected to the pickup circuit, the host and the car networking box respectively, and used for receiving the audio signal and increasing the voltage and amplitude of the audio signal; and The second regulating module is connected to the first regulating module and the Internet of Vehicles box respectively, and the second regulating module is used to receive the amplified audio signal and reduce the voltage and amplitude of the audio signal to output to the Internet of Vehicles box.

2. The signal processing circuit according to claim 1, characterized in that: The first adjustment module includes: A bias unit, wherein a first end of the bias unit is connected to the host and the IoV box, and a second end of the bias unit is connected to the pickup circuit for receiving the audio signal; Wherein, the host and the Internet of Vehicles box are used to provide a bias voltage to the audio signal via the bias unit.

3. The signal processing circuit according to claim 2, characterized in that: The bias unit includes a first resistor, a second resistor, a third resistor and a fourth resistor; One end of the first resistor and one end of the second resistor are connected to the first end of the pickup circuit, the other end of the first resistor and the other end of the second resistor are connected to the host and the Internet of Vehicles box, one end of the third resistor and one end of the fourth resistor are connected to the second end of the pickup circuit, and the other end of the third resistor and the other end of the fourth resistor are grounded.

4. The signal processing circuit according to claim 2, characterized in that: The first adjustment module also includes: a filter unit, wherein a first end of the filter unit is connected to a third end of the bias unit, and a second end of the filter unit is connected to a fourth end of the bias unit; and A connector unit, wherein the first end of the connector unit is connected to the third end of the filter unit, the second end of the connector unit is connected to the fourth end of the filter unit, the third end of the connector unit is connected to the first end of the second regulating module, and the fourth end of the connector unit is connected to the second end of the second regulating module.

5. The signal processing circuit according to claim 4, characterized in that: The filtering unit includes a first inductor, a second inductor, a first capacitor, a second capacitor, a third capacitor and a fourth capacitor; One end of the first inductor is connected to the first plate of the first capacitor and the third end of the bias unit, the other end of the first inductor is connected to the first plate of the second capacitor and the first end of the connector unit, one end of the second inductor is connected to the first plate of the third capacitor and the fourth end of the bias unit, the other end of the second inductor is connected to the first plate of the fourth capacitor and the second end of the connector unit, and the second plate of the first capacitor, the second plate of the second capacitor, the second plate of the third capacitor and the second plate of the fourth capacitor are grounded respectively.

6. The signal processing circuit according to any one of claims 1 to 5, characterized in that: The Internet of Vehicles box includes a control chip; the second adjustment module includes: A voltage regulating unit, the voltage regulating unit is connected to the first regulating module and the control chip respectively, and the voltage regulating unit is used to receive the amplified audio signal and reduce the voltage and amplitude of the audio signal to output to the control chip.

7. The signal processing circuit according to claim 6, characterized in that: The voltage regulating unit includes a fifth resistor and a sixth resistor; One end of the fifth resistor and one end of the sixth resistor are connected to the first end of the first regulating module and the first end of the control chip, and the other end of the fifth resistor and the other end of the sixth resistor are grounded.

8. The signal processing circuit according to claim 6, characterized in that: The voltage regulating unit comprises: A seventh resistor, one end of the seventh resistor is connected to the first end of the first regulating module and the first end of the control chip, and the other end of the seventh resistor is connected to the second end of the first regulating module and the second end of the control chip.

9. A vehicle-mounted voice system, characterized in that: It comprises a sound pickup circuit, a host, a car networking box and a signal processing circuit as described in any one of claims 1 to 8.

10. A vehicle, characterized in that: It comprises a vehicle body and the in-vehicle voice system as claimed in claim 9, wherein the in-vehicle voice system is mounted on the vehicle body.

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