CN115190397A - Stereo double-track audio processor for broadcast television transmitting station - Google Patents
Stereo double-track audio processor for broadcast television transmitting station Download PDFInfo
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- CN115190397A CN115190397A CN202210799627.2A CN202210799627A CN115190397A CN 115190397 A CN115190397 A CN 115190397A CN 202210799627 A CN202210799627 A CN 202210799627A CN 115190397 A CN115190397 A CN 115190397A
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- H04R5/00—Stereophonic arrangements
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Abstract
The invention discloses a stereo two-channel audio processor for a broadcast television transmitting station, and relates to the field of audio processing equipment. The invention comprises an audio signal analog input circuit, a digital input circuit, a DSP digital signal processing circuit, an analog output circuit, a digital output circuit and a central control unit CPU; the audio signal analog input circuit is connected with the analog output in sequence through the analog input gain adjusting circuit, the A/D analog-to-digital conversion circuit, the DSP digital signal processing unit, the D/A digital-to-analog conversion circuit and the analog output circuit; the digital audio input circuit is connected with the digital input circuit in sequence through the digital audio decoding circuit, the DSP digital signal processing unit and the digital input circuit. The invention processes the analog audio or digital audio signal by adopting the audio processing chip taking the DSP as the core, and is compatible with the amplitude modulation audio signal and the frequency modulation audio signal; the invention can remove the background noise of the audio signal by adopting the professional filter, and has important effect on improving the quality of the broadcasting signal, the audio signal-to-noise ratio and the audio loudness.
Description
Technical Field
The invention belongs to the field of audio processing equipment, and particularly relates to a stereo dual-channel audio processor for a broadcast television transmitting station, which can be compatible with various signal formats and well overcome the defects of the audio processor in the original market.
Background
With the development of the broadcast television industry, the program sources of radio stations and television stations are increasingly abundant, the manufacturing means and carriers of the program sources tend to be diversified, after the audios of different program sources are broadcast, a user can have the phenomenon of large and small sound during listening, even the overload protection of a transmitter can be caused, and the broadcasting quality is seriously influenced due to the fact that the amplitude of other audio signals is small and background noise exists.
The original control of the broadcast television station transmitting department to the audio signal sent is that the on-duty person of the broadcasting computer lab adjusts with the manual attenuator, there are very big randomness, postponement, can't guarantee better tone quality, especially it is obvious when the program broadcasting switches over, there is no good solution to the noise problem either, some audio processors of manufacturers use the mode of the amplitude limiter to compress the too big signal level afterwards, but the reaction rate is slow, and still can't solve the small signal and signal background noise problem.
The present document addresses the deficiencies of the prior art:
1. the original control of the broadcast television station transmitting department to the sent audio signal is that the on-duty person of the broadcast computer room adjusts by a manual attenuator, which has great randomness and lagged property, can not ensure better tone quality, especially when the program broadcast is switched.
2. Some manufacturers produce audio processors that solve some of the problems, but do not solve the drawbacks at all. If the large signal is compressed by using a limiter, the method has slow response speed, and the problem of small signal and signal background noise still cannot be solved.
A multifunctional audio processor specially designed for a broadcast television transmitting station is designed, is compatible with various signal formats, and can well overcome the defects of the audio processor in the original market.
Disclosure of Invention
The invention aims to provide a stereo dual-channel audio processor for a broadcast television transmitting station, which can process an analog audio or digital audio (AES/EBU) signal by adopting a professional audio processing chip and taking a DSP as a core to process an audio signal, is compatible with an amplitude modulation audio signal and a frequency modulation audio signal, removes bottom noise by using a professional filter, can save a distributor by outputting one in two after signal processing, and solves the problems of poor processing effect and influence on broadcasting quality of the conventional audio processor for the broadcast television station.
In order to solve the technical problems, the invention is realized by the following technical scheme:
the invention relates to a stereo double-track audio processor for a broadcast television transmitting station, which comprises an audio signal analog input circuit, a digital input circuit, a DSP digital signal processing circuit, an analog output circuit, a digital output circuit and a central control unit (CPU); the audio signal analog input circuit is connected with the analog output in sequence through an analog input gain adjusting circuit, an A/D (analog-to-digital) conversion circuit, a DSP (digital signal processor) digital signal processing unit, a D/A (digital-to-analog) conversion circuit and an analog output; the digital audio input circuit is connected with the digital input circuit in sequence through the digital audio decoding circuit, the DSP digital signal processing unit and the digital input circuit; the central control unit CPU is also connected with a reset circuit and a power supply circuit; and the central control unit CPU is respectively in bidirectional connection with the RJ45 network communication interface, the panel control and display circuit and the memory circuit.
As a preferred technical solution, the audio signal analog input circuit uses NE5532. Transforming the balanced signal into an unbalanced signal; the analog input gain adjusting circuit realizes the size adjustment of input gain by using AD7524 and 74HC 595; the A/D analog-to-digital conversion circuit performs A/D conversion on a signal sent from the front end; the digital input circuit is changed into an unbalanced signal by UA9637 after completing digital signal reception; the digital audio decoding circuit uses AK4113 to decode the signal sent from the front end, and the decoded digital signal I2S and the I2S of A/D conversion are both sent to the DSP digital signal processing platform for processing.
As a preferred technical scheme, the digital signal enters a DSP digital signal processing platform for processing, and the processed digital signal is divided into four paths and sent to a later stage for processing; of the four paths, two paths are used for analog output, and the other two paths are used for digital signal output.
As a preferred technical scheme, the digital signals pass through a D/A digital-to-analog conversion circuit, digital-to-analog conversion is completed by AD1938 and then the digital-to-analog conversion is sent to an analog output circuit, conversion from unbalanced to balanced signals is completed by NE5532, two paths of digital signals are directly sent to a digital output circuit, digital signal sending is achieved by a chip DIT4192, a central control circuit controls output gain, a storage circuit is formed by MB85RS64, set various parameters are stored, the parameters are called when the computer is started next time and kept in a last set state, and a reset circuit adopts MAX811S to provide power-on automatic reset and manual reset.
As a preferred technical solution, the power supply circuit is implemented by using a switching power supply; the switching power supply inputs +12V, -12V and +5V voltage to each circuit.
As a preferred technical solution, the central control unit CPU employs an STM32F407VGT6 chip; the panel control and display circuit adopts an OLED screen.
As a preferred technical scheme, when the audio processor is started, the central control unit CPU sends control and configuration commands to each part of the circuit, and the DSP digital signal processing platform performs audio processing work according to the set parameters after receiving the commands; the panel control and display circuit displays the current working state of the audio processor, and the input and output LED bars display the audio level of real-time input and output.
As a preferred technical solution, the RJ45 network communication interface is connected to a computer, and is used to remotely set, control and display the audio processor.
The invention has the following beneficial effects:
(1) The invention adopts the audio processing chip taking DSP as the core to process the audio signals, can realize the processing of analog audio or digital audio (AES/EBU) signals, is compatible with amplitude modulation audio signals and frequency modulation audio signals, uses a filter to remove bottom noise, can save a distributor by outputting one by two after the signal processing, removes the background noise of the audio signals, and improves the quality of the broadcasting signals, the audio signal-to-noise ratio and the audio loudness;
(2) The invention can solve the problem of large audio program level difference caused by recording, exchanging, different program contents and using different audio devices by compressing the dynamic range of the program signal.
(3) The invention filters the signal bottom noise through the filter, improves the audio signal-to-noise ratio and the audio loudness, improves the program quality, improves the average modulation degree and enlarges the coverage range.
Of course, it is not necessary for any product in which the invention is practiced to achieve all of the above-described advantages at the same time.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic diagram of a stereo two-channel audio processor for a broadcast television transmitting station according to the present invention;
FIG. 2 is a schematic diagram of a front side of an audio processor;
fig. 3 is a schematic diagram of the back side of an audio processor.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the present invention is a stereo two-channel audio processor for a broadcast television transmitting station, including an audio signal analog input circuit, a digital input circuit, a DSP digital signal processing circuit, an analog output circuit, a digital output circuit, and a central control unit CPU; the audio signal analog input circuit is connected with the analog output in sequence through the analog input gain adjusting circuit, the A/D analog-to-digital conversion circuit, the DSP digital signal processing unit, the D/A digital-to-analog conversion circuit and the analog output; the digital audio input circuit is connected with the digital input circuit in sequence through the digital audio decoding circuit, the DSP digital signal processing unit and the digital input circuit; the central control unit CPU is also connected with a reset circuit and a power supply circuit; the central control unit CPU is respectively connected with the RJ45 network communication interface, the panel control and display circuit and the memory circuit in two directions.
The audio signal analog input circuit uses NE5532. Transforming the balanced signal into an unbalanced signal; the analog input gain adjusting circuit realizes the size adjustment of the input gain by using AD7524 and 74HC 595; the A/D conversion circuit performs A/D conversion on the signal sent from the front end; the digital input circuit is changed into an unbalanced signal by UA9637 after completing digital signal reception; the digital audio decoding circuit uses AK4113 to decode the signal from the front end, and both the decoded digital signal I2S and the A/D converted I2S are sent to the DSP digital signal processing platform for processing.
The digital signal enters a DSP digital signal processing platform for processing, and the processed digital signal is divided into four paths and sent to a later stage for processing; of the four paths, two paths are used as analog output, and the other two paths are used as digital signal output.
Digital signals pass through a D/A digital-to-analog conversion circuit, digital-to-analog conversion is completed by AD1938 and then are sent to an analog output circuit, conversion from unbalanced signals to balanced signals is completed by NE5532, two paths of digital signals are directly sent to the digital output circuit, digital signal sending is achieved by a chip DIT4192, a central control circuit controls output gain, a storage circuit is formed by MB85RS64, set various parameters are stored, calling parameters are kept in a set state when the computer is started next time, and a reset circuit adopts MAX811S to provide power-on automatic reset and manual reset.
The power supply circuit is completed by using a switching power supply; the switching power supply inputs +12V, -12V and +5V voltage to each circuit.
The central control unit CPU adopts an STM32F407VGT6 chip; the panel control and display circuit adopts an OLED screen.
When the audio processor is started, the central control unit CPU sends control and configuration commands to all circuits, and the DSP digital signal processing platform carries out audio processing work according to set parameters after receiving the commands; the panel control and display circuit displays the current working state of the audio processor, and the input and output LED bars display the audio level of real-time input and output.
And the RJ45 network communication interface is connected with a computer and used for realizing remote setting, control and display of the audio processor.
Example one
An analog input circuit of the stereo two-channel audio processor converts a balanced signal into an unbalanced signal by using NE5532, an analog gain control circuit realizes the adjustment of input gain by using AD7524 and 74HC595, an analog-to-digital circuit carries out A/D conversion on a signal sent from a front end by using AD1938, a digital input circuit finishes digital signal reception by using UA9637 and converts the digital signal into the unbalanced signal, a digital decoding circuit decodes the signal sent from the front end by using AK4113, and the decoded digital signal I2S and the I2S of the A/D conversion are both sent to a digital signal processing platform DSP for processing.
The DSP downloads various designed functional modules into the DSP by using a new algorithm, and the DSP completes the following functions according to the functions of the modules: 1. the device comprises a background noise removing module 2, a dynamic peak amplitude limiting module 3, an automatic gain control module 4, a multi-section equalization compression processing module 5 and a loudness control module.
After the digital signals enter the DSP processing platform, each functional module finishes respective work according to preset task parameters, and the processed digital signals are divided into four paths to be sent to a post-stage for processing. The two paths are used for analog output and the two paths are used for digital signal output, digital signals are subjected to digital-to-analog conversion by an AD1938 through a digital-to-analog conversion circuit D/A and then are sent to an analog output circuit, the digital signals are converted and output from unbalanced signals to balanced signals by an NE5532, the two paths of digital signals are directly sent to a digital output circuit, digital signal sending is achieved by a chip DIT4192, a central control circuit controls the output gain, a storage circuit is formed by MB85RS64, set various parameters are stored, the calling parameters are kept in the last set state when the computer is started next time, a reset circuit is achieved by MAX811, and power-on automatic reset and manual reset are provided. The power supply circuit is completed by using a switching power supply, the switching power supply outputs +12V, -12V and +5V voltages to each part of circuits, a Central Processing Unit (CPU) adopts an STM32F407VGT6 chip, a key and a display circuit display screen use an OLED (organic light emitting diode) screen, a light bar uses an LED block, the central processing unit sends control and configuration commands to each part of circuits when the LED lamp is started, a Digital Signal Processor (DSP) performs audio processing work after receiving the commands and pressing set parameters, the CPU drives the display screen to display the current working state of the audio processor, and an input/output LED bar displays the real-time input/output audio level. The RJ network interface can be connected with a computer, and can realize remote setting, control and display of the audio processor.
It should be noted that, in the above system embodiment, each included unit is only divided according to functional logic, but is not limited to the above division as long as the corresponding function can be implemented; in addition, specific names of the functional units are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present invention.
In addition, it is understood by those skilled in the art that all or part of the steps in the method for implementing the embodiments described above may be implemented by a program instructing associated hardware, and the corresponding program may be stored in a computer-readable storage medium.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.
Claims (8)
1. A kind of stereo double track audio processor used for radio and television launching pad, including audio signal analog input circuit, digital input circuit, DSP digital signal processing circuit, analog output circuit, digital output circuit and central control unit CPU, characterized by that;
the audio signal analog input circuit is connected with the analog output in sequence through an analog input gain adjusting circuit, an A/D (analog-to-digital) conversion circuit, a DSP (digital signal processor) digital signal processing unit, a D/A (digital-to-analog) conversion circuit and an analog output;
the digital audio input circuit is connected with the digital input circuit in sequence through the digital audio decoding circuit, the DSP digital signal processing unit and the digital input circuit;
the central control unit CPU is also connected with a reset circuit and a power supply circuit; and the central control unit CPU is respectively in bidirectional connection with the RJ45 network communication interface, the panel control and display circuit and the memory circuit.
2. A stereo two-channel audio processor for a broadcast television transmitting station as defined in claim 1, wherein the audio signal analog input circuit uses NE5532. Transforming the balanced signal into an unbalanced signal; the analog input gain adjusting circuit realizes the size adjustment of the input gain by using AD7524 and 74HC 595; the A/D conversion circuit performs A/D conversion on a signal sent from the front end; the digital input circuit is changed into an unbalanced signal by UA9637 after completing digital signal reception; the digital audio decoding circuit uses AK4113 to decode the signal sent from the front end, and the decoded digital signal I2S and the I2S of A/D conversion are both sent to the DSP digital signal processing platform for processing.
3. A stereo binaural audio processor for a broadcast television transmitter as claimed in claim 2, wherein the digital signal is processed by a DSP digital signal processing stage, and the processed digital signal is divided into four paths for further processing; of the four paths, two paths are used for analog output, and the other two paths are used for digital signal output.
4. A stereo two-channel audio processor for radio and television transmitter as claimed in claim 3, wherein the digital signals are passed through D/A converter circuit, D/A converted by AD1938 and then sent to analog output circuit, NE5532 converted from unbalanced to balanced signals and sent directly to digital output circuit, and then sent to chip DIT4192 for digital signal transmission, the central control circuit controls the output gain, the storage circuit is made up of MB85RS64, the storage circuit stores various parameters that are set, the parameters that are called when the transmitter is turned on next time are kept in the last set state, and the reset circuit employs MAX811S to provide power-on automatic reset and manual reset.
5. A stereo two-channel audio processor for a broadcast television transmitting station as defined in claim 1, wherein the power supply circuit is implemented using a switching power supply; the switching power supply inputs +12V, -12V and +5V voltage to each circuit.
6. A stereo binaural audio processor for a broadcast television transmitting station according to claim 1, characterized in that the central control unit CPU employs an STM32F407VGT6 chip; the panel control and display circuit adopts an OLED screen.
7. A stereo two-channel audio processor for broadcast TV transmitter as claimed in claim 6, wherein when the audio processor is powered on, the CPU sends control and configuration commands to the circuits of each part, and the DSP digital signal processing platform performs audio processing after receiving the commands according to the set parameters; the panel control and display circuit displays the current working state of the audio processor, and the input and output LED bars display the audio level of real-time input and output.
8. A stereo two-channel audio processor for a broadcast television transmitting station as defined in claim 1 wherein the RJ45 network communications interface is connected to a computer for remote setup, control and display of the audio processor.
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| CN202210799627.2A CN115190397A (en) | 2022-07-06 | 2022-07-06 | Stereo double-track audio processor for broadcast television transmitting station |
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| CN202210799627.2A CN115190397A (en) | 2022-07-06 | 2022-07-06 | Stereo double-track audio processor for broadcast television transmitting station |
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2022
- 2022-07-06 CN CN202210799627.2A patent/CN115190397A/en active Pending
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| US20090105858A1 (en) * | 2006-02-07 | 2009-04-23 | Anthony Bonglovi | System and method for digital signal processing |
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