CN216491016U

CN216491016U - Microphone signal circuit for long-distance transmission

Info

Publication number: CN216491016U
Application number: CN202122745992.9U
Authority: CN
Inventors: 黄伟泉; 周瑞君
Original assignee: Shenzhen Eacom Communication Co ltd
Current assignee: Shenzhen Eacom Communication Co ltd
Priority date: 2021-11-10
Filing date: 2021-11-10
Publication date: 2022-05-10
Anticipated expiration: 2031-11-10

Abstract

The utility model discloses a microphone signal circuit for long-distance transmission, which comprises a microphone module, an operational amplification module, an A/D conversion module, a noise processing module, a D/A conversion module, a long-distance transmission line and an expansion module, and is characterized in that the microphone module comprises four microphones, the operational amplification module is connected with the microphone module, the A/D conversion module is an 8-channel ADC chip, the noise processing module is a DSP chip, the DSP chip is connected with a control mainboard in a device, the D/A conversion module is an AKM4420 chip, the long-distance transmission line is a customized network cable RJ45, and the expansion module comprises a loudspeaker and a microphone system. The utility model has high circuit integration level, more reliable microphone signal processing, more stable signal transmission process and longer transmission distance. The communication requirements of large conferences and important conferences can be met.

Description

Microphone signal circuit for long-distance transmission

Technical Field

The utility model relates to the technical field of microphone signal circuits for long-distance transmission, in particular to a microphone signal circuit for long-distance transmission.

Background

In the field of conference telephones, the omnidirectional microphone has the problems that the extension unit cannot be connected, or the connecting line between the extension unit and the host computer is too short, or the sound quality of transmitted sound is poor, and the like, and the communication requirements of large conferences and important conferences cannot be met.

Through retrieval, the microphone signal belongs to a weak signal, and is very easily interfered in the long-distance transmission process, so that the conversation quality is influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the defects in the prior art and provides a microphone signal circuit for long-distance transmission.

In order to achieve the purpose, the utility model adopts the following technical scheme:

the utility model provides a long distance transmission's microphone signal circuit, includes microphone module, operation amplification module, AD conversion module, noise processing module, DA conversion module, long distance transmission line and expansion module, the microphone module includes four microphones, operation amplification module links to each other with the microphone module, AD conversion module is 8 way ADC chips, noise processing module is the DSP chip, and the DSP chip links to each other with the inside control mainboard of device, DA conversion module is the AKM4420 chip, long distance transmission line is customization net twine RJ45, the expansion module includes loudspeaker and microphone system.

Furthermore, two sides of the customized network cable RJ45 are respectively connected with an EXT interface of the expansion module and an EXT interface of the microphone.

The utility model has the beneficial effects that:

1. firstly, a microphone picks up audio information, a microphone signal is amplified by an operational amplification module and transmitted to an A/D conversion module, an analog signal of the microphone is converted into a digital signal, the digital signal is subjected to noise reduction and echo elimination by a DSP chip on a noise processing module, the digital signal is converted into an analog signal by a D/A conversion module and transmitted to an expansion unit on a customized network RJ45 with the length of more than 5 meters, the analog signal is transmitted to an expansion unit for information interaction, the scheme utilizes a circuit and a long-distance customized network cable to comprehensively solve the noise interference problem of the long-distance transmission microphone signal, in use, the echo elimination mode of SV15 is that an off-hook key and a microphone mute key are pressed simultaneously for 5 seconds to enter an echo elimination mode, a green light of a key indicator flickers for 3 times and the microphone state indicator is a green light, otherwise, when the green light of the key indicator flickers for 3 times and the microphone state indicator is a red light, the utility model has the advantages that the circuit scheme of the microphone signal for long-distance transmission is high in integration level, the microphone signal processing is more reliable, the signal is more stable in the transmission process, the transmission distance is longer, and the communication requirements of a large conference and an important conference can be met.

Drawings

Fig. 1 is a flowchart of a long-distance microphone signal circuit according to the present embodiment;

fig. 2 is a schematic diagram of external connection of a long-distance microphone signal circuit according to this embodiment.

Detailed Description

The technical solution of the present patent will be described in further detail with reference to the following embodiments.

Reference will now be made in detail to embodiments of the present patent, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present patent and are not to be construed as limiting the present patent.

In the description of this patent, it is to be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for the convenience of describing the patent and for the simplicity of description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the patent.

In the description of this patent, it is noted that unless otherwise specifically stated or limited, the terms "mounted," "connected," and "disposed" are to be construed broadly and can include, for example, fixedly connected, disposed, detachably connected, disposed, or integrally connected and disposed. The specific meaning of the above terms in this patent may be understood by those of ordinary skill in the art as appropriate.

Example 1

Referring to fig. 1-2, a microphone signal circuit for long-distance transmission includes a microphone module, an operational amplifier module, an a/D conversion module, a noise processing module, a D/a conversion module, a long-distance transmission line and an expansion module, wherein the microphone module includes four microphones mainly responsible for environmental sound pickup, collecting the speaking sound of a conference, converting the sound into an electrical signal form and transmitting the electrical signal form to an internal control main board circuit of an omnidirectional microphone, and has a 360-degree full-range sound pickup effect, the operational amplifier module is connected with the microphone module, amplifies the electrical signal transmitted from the microphone to a control board, increases the gain of the electrical signal, the signal of the microphone is a weak signal in the circuit, and is very susceptible to distortion and noise generation caused by other elements and current in the circuit, and the signal amplification of the microphone is largely prevented from being interfered by the internal circuit, the noise processing module has the main functions of reducing or eliminating the noise of the microphone and eliminating the echo of the microphone, and in addition, the SP chip is used as a digital signal processor to convert an analog signal into a digital signal for high-speed real-time processing of a special processor and has the interface functions of high speed, flexibility, programmability and low power consumption, the D/A conversion module is an AKM4420 chip, the long-distance transmission line is a customized network cable RJ45, the customized network cable RJ45 line is more than five meters, and the shielding transmission line can prevent external signal interference, is a comprehensive measure for enhancing the anti-interference capability of the device by matching with a circuit scheme, and the expansion module comprises a loudspeaker and a microphone system, the expansion module has the main function of information communication with the host, the loudspeakers and the microphones of the main unit and the expansion unit are completely synchronous, and the sound pick-up and sound reproduction capabilities of the omnidirectional microphone can be optimized by mutual control.

The working principle is as follows: firstly, a microphone picks up audio information, a microphone signal is amplified by an operational amplification module and transmitted to an A/D conversion module, an analog signal of the microphone is converted into a digital signal, the digital signal is subjected to noise reduction and echo elimination by a DSP chip on a noise processing module, the digital signal is converted into an analog signal by a D/A conversion module and transmitted to an expansion unit on a customized network RJ45 with the length of more than 5 meters, the analog signal is transmitted to an expansion unit for information interaction, the scheme utilizes a circuit and a long-distance customized network cable to comprehensively solve the noise interference problem of the long-distance transmission microphone signal, in use, the echo elimination mode of SV15 is that an off-hook key and a microphone mute key are pressed simultaneously for 5 seconds to enter an echo elimination mode, a green light of a key indicator flickers for 3 times and the microphone state indicator is a green light, otherwise, when the green light of the key indicator flickers for 3 times and the microphone state indicator is a red light, the utility model has the advantages that the circuit scheme of the microphone signal for long-distance transmission is high in integration level, the microphone signal processing is more reliable, the signal is more stable in the transmission process, the transmission distance is longer, and the communication requirements of a large conference and an important conference can be met.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and equivalent alternatives or modifications according to the technical solution of the present invention and the inventive concept thereof should be covered by the scope of the present invention.

Claims

1. The utility model provides a long distance transmission's microphone signal circuit, includes microphone module, operational amplification module, AD conversion module, noise processing module, DA conversion module, long distance transmission line and expansion module, its characterized in that, the microphone module includes four microphones, the operational amplification module links to each other with the microphone module, AD conversion module is 8 way ADC chips, noise processing module is the DSP chip, and the DSP chip links to each other with the inside control mainboard of device, DA conversion module is AKM4420 chip, long distance transmission line is customization net twine RJ45, the expansion module includes loudspeaker and microphone system.

2. The microphone signal circuit for long distance transmission of claim 1, wherein two sides of the customized network cable RJ45 are connected to an EXT interface of the expansion module and an EXT interface of the microphone respectively.