CN107295444A - Wireless audio transmission system based on ZigBee - Google Patents
Wireless audio transmission system based on ZigBee Download PDFInfo
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- CN107295444A CN107295444A CN201710579625.1A CN201710579625A CN107295444A CN 107295444 A CN107295444 A CN 107295444A CN 201710579625 A CN201710579625 A CN 201710579625A CN 107295444 A CN107295444 A CN 107295444A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2420/00—Details of connection covered by H04R, not provided for in its groups
- H04R2420/03—Connection circuits to selectively connect loudspeakers or headphones to amplifiers
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- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
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Abstract
The invention discloses a kind of wireless audio transmission system based on ZigBee, including audio collection unit, for gathering voice data；Audio transmission unit, using CC2530 chips, audio collection unit is collected voice data and carries out analog-to-digital conversion by the 8051CPU for being carried by CC2530, convert analog signals into the data signal that machine can be recognized, the voice data collected is carried out after coding compression by software section, data are wirelessly sent to audio playing unit audio playing unit using CC2530 wireless transceiver, for receiving the data come by CC2530 transmitter wireless transmissions, and carried out by filter circuit after denoising, it is connected to after being amplified again by amplifying circuit on loudspeaker, realize the broadcasting of audio；Power supply unit, for providing voltage output to audio collection, transmission and playing module, it is ensured that the voltage supply for having stabilization of each module.
Description
Technical field
The present invention relates to field of video transmission, and in particular to a kind of wireless audio transmission system based on ZigBee.
Background technology
Wireless multimedia sensor is quite extensive in current use, can be big by wireless multimedia sensor
It is big to save human resources.Wireless multimedia sensor utilizes the sound in surrounding environment where the various sensors measurement built in node
Sound, image, infrared, radar and seismic signal, so that data and signal required for obtaining us.On communication mode, to the greatest extent
Pipe can be communicated using various ways, but the short-distance wireless communication technology of generally low-power low-power consumption is considered as optimum
The realization of sensor network, for clarity, generally we are referred to as wireless sensor network.Wireless sensor network compared to
Traditional wireless network has completely different purpose of design, in the range of wireless sensor network, except small part node is needed
Move outer, most of nodes are all static.Because they are often in the exceedingly odious environment that people can not approach, have
Even operate in danger environment in, the energy can not timely substitute, therefore, extend network node life cycle strategy
Key issue of the design effectively into wireless sensor network.User proposes completely to wireless sensor network and traditional sensors
Different technical requirements, traditional sensor is using data as core, and wireless multimedia sensor is then to transmit data as target.
In the sensor network for having a large amount of network nodes, the distance between two nodes close to each other are very near, use
Multi-hop communication pattern largely reduces power consumption, while the disguise of communication also increased, usual long range channel radio
Letter is subject to the upset of outside noise, can be obtained by and solves well using multi-hop communication this problem.Just because of existing
Real requirement and the presence of various restraining factors, are also asked to study the development of sensor network and having researched and proposed newly technical
Topic.So development of wireless senser for many years is made a general survey of, is addressed the problem of more and more and technology is also continuous
Renewal and breakthrough.It true can only carry out obtaining the wireless biography of simple data in simple data collection and processing monitoring task
Sensor network system is general character in the market, with seldom information data content, poor flexibility, and not extensive
Application prospect, therefore, the wireless multimedia sensor arisen at the historic moment will replace conventional unifunctional wireless senser, this
The sensor node that sensor has a variety of perceptible medium types is constituted.Share out the work and help one another to handle using resource mutually between node and appoint
Business, has different treating method and perception for different media.
The content of the invention
To solve the above problems, the invention provides a kind of wireless audio transmission system based on ZigBee.
To achieve the above object, the technical scheme taken of the present invention is：
Wireless audio transmission system based on ZigBee, including
Audio collection unit, using the audio sensor being made up of microphone, audio collection circuit, for gathering audio number
According to；
Audio transmission unit, using CC2530 chips, for the 8051CPU that is carried by CC2530 by audio collection unit
Collected voice data carries out analog-to-digital conversion, the data signal that machine can be recognized is converted analog signals into, by software portion
Divide and the voice data collected is carried out after coding compression, data are wirelessly sent to audio using CC2530 wireless transceiver
Broadcast unit；
Audio playing unit, for receiving the data come by CC2530 transmitter wireless transmissions, and passes through filtered electrical
Road carries out after denoising, then is connected on loudspeaker after being amplified by amplifying circuit, realizes the broadcasting of audio；
Power supply unit, for providing voltage output to audio collection, transmission and playing module, it is ensured that each module
There is stable voltage supply.
Preferably, the audio playing unit selects 0.8 Ω power 0.5W loudspeaker.
Preferably, the audio collection circuit is made up of MIC microphones, resistance, electric capacity, amplifier, and audio is from MIC Mikes
Wind is inputted, and carries out current limliting by 10K R1, VCC is powered using extraneous 4-8V dc sources.C1 uses the conduct of electric capacity 104
Coupled capacitor, the high and low frequency signal in front stage circuits is separated, filter out the high frequency in input signal by shunt capacitance C3
Noise, by C4 electric capacity 10uF control to 200 times of voltage amplification, is used using electric capacity 220uF C6 as output coupling, cut-off
The direct current signal of DC voltage and coupling audio, the electric capacity C7 power supply sources filtering from 470uF is used, and removes power pin
Noise, stable IC power supply, the output of electric capacity C8 stabilized power sources；Signal is carried out to voltage in circuit from LM386 power amplifiers
Amplification, can change multiplication factor, from twin voltage comparator integrated circuit, pin 2 and pin 3 are defeated by the size for changing C4
Enter analog signal, pin 1 then exports binary data signal, and audio signal will be output to after amplification and filtering process
CC2530 I/O mouths.
Preferably, the audio transmission unit includes CC2530 chips, module interface base and reset circuit, described
CC2530 chips carry 8051CPU processors and RF transceiver, and each interface of module interface base is all connected to accordingly
Each pin of CC2530 modules, so as to allow supply voltage, sensor signal and reset signal to enter correct CC2530 cores
In piece pin, complete to CC2530 chip power supplies, signal acquisition and reset operation；The low level that reset circuit is produced is input to
A CC2530 reset pin, performs a series of hardware initialization operation, including：CC2530 chips are 21 I/O pins
All it is configured to input pull-up；CPU program pointers 0x0000 address assignments to CC2530, program is since 0x0000 addresses
Perform；All peripheral hardware initialization of register of CC2530 chips are reset values, and after completing to reset, CC2530 chips restart
Operation.
Preferably, CC2530 antenna uses the flagpole antenna of 2db SMA interfaces.
Preferably, the power supply unit is powered using battery or dc source is powered.
The invention has the advantages that：
1st, the wireless audio transmission system of the invention based on ZigBee, can solve traditional wire mode and carry out data perception band
The problems such as high cost come, low preparation rate, with wireless self-networking, low cost, installation and deployment are flexible, anti-interference, scalability
By force, the high advantage of reliability.
2nd, the wireless audio transmission system of the invention based on ZigBee can promote the use of stock control, product quality prison
Control, Industry Control, earthquake territory monitoring and the multiple fields such as coal mine underground monitoring, positioning and cell security protection, further lifting prison
Survey monitoring field intellectuality, the level of IT application.
Brief description of the drawings
Fig. 1 is the structural representation of the embodiment of the present invention.
Fig. 2 is audio collection schematic diagram.
Fig. 3 is CC2530 communication module structured flowcharts.
Fig. 4 is CC2530 chip circuit figures.
Fig. 5 is module interface schematic diagram.
Fig. 6 is reset circuit figure.
Fig. 7 is audio playing principles figure.
Fig. 8 is power module schematic diagram
Fig. 9 is voltage conversion schematic diagram.
Embodiment
In order that objects and advantages of the present invention are more clearly understood, the present invention is carried out with reference to embodiments further
Describe in detail.It should be appreciated that the specific embodiments described herein are merely illustrative of the present invention, it is not used to limit this hair
It is bright.
As shown in figure 1, the embodiments of the invention provide a kind of wireless audio transmission system based on ZigBee, including
Audio collection unit, using the audio sensor being made up of microphone, audio collection circuit, for gathering audio number
According to；
Audio transmission unit, using CC2530 chips, for the 8051CPU that is carried by CC2530 by audio collection unit
Collected voice data carries out analog-to-digital conversion, the data signal that machine can be recognized is converted analog signals into, by software portion
Divide and the voice data collected is carried out after coding compression, data are wirelessly sent to audio using CC2530 wireless transceiver
Broadcast unit；
Audio playing unit, for receiving the data come by CC2530 transmitter wireless transmissions, and passes through filtered electrical
Road carries out after denoising, then is connected on loudspeaker after being amplified by amplifying circuit, realizes the broadcasting of audio；
Power supply unit, for providing voltage output to audio collection, transmission and playing module, it is ensured that each module
There is stable voltage supply.
The audio collection circuit is made up of microphone, resistance, electric capacity, amplifier, and VCC uses external world's 4-8V dc sources
It is powered；Audio carries out current limliting by 10K R1, coupled capacitor is used as by electric capacity 104C1, lead to from MIC microphone inputs
Cross shunt capacitance C3 and filter out noise, the high and low frequency signal in front stage circuits is separated, the high frequency filtered out in input signal is made an uproar
Sound；By C4 electric capacity 10uF control to 200 times of voltage amplification, by electric capacity 220uF C6 output couplings, separate DC voltage
And the direct current signal of coupling audio, power filter is carried out by 470uF electric capacity C7, removes the noise of power pin, stable
IC power supply, the output of electric capacity C8 stabilized power sources；Signal amplification is carried out to the voltage in circuit from LM386 power amplifiers,
LM386 is that LM386 can be adjusted gain and the power consumption of itself is very low for audio frequency process special power amplifier,
Multiplication factor is changed by the size for changing C4；LM393 devices i.e. twin voltage comparator integrated circuit has been selected, mould is may be used as
Intend circuit and the interface of digital circuit, pin 2 and the input analog signal of pin 3, pin 1 then exports binary data signal,
The analog-digital converter of one can be considered as.Audio signal is by the I/O mouths for amplifying with CC2530 being output to after filtering process, sound
Frequency Acquisition Circuit figure is as shown in Figure 2.
Audio transmission circuit is designed
CC2530 carries 8051CPU processors and RF transceiver.Wireless transport hardware it is main by wireless radio frequency circuit and
Antenna is constituted, and Fig. 3 is the structure chart of CC2530 modules, and Fig. 4 show CC2530 chip circuit figures.
The design of processing circuit module also includes its module interface base and reset circuit.Module interface schematic diagram such as Fig. 5
Shown, its effect is that CC2530 modules can be connected with backplane circuit to use.Each interface of interface pedestal all connects accordingly
Then each pin of CC2530 modules, correct so as to allow supply voltage, sensor signal and reset signal to enter
In CC2530 chip pins, complete to CC2530 chip power supplies, signal acquisition and reset the functions such as operation.
Button resets, and presses S3 keys, reset circuit will produce a low level.The low level input that reset circuit is produced
To a CC2530 reset pin, a series of hardware initialization operation is performed.Resetting operation includes：CC2530 chips are 21
Individual I/O pins are all configured to input pull-up；CPU program pointers 0x0000 address assignments to CC2530, program from
0x0000 addresses start to perform；All peripheral hardware initialization of register of CC2530 chips are reset values.After completing to reset,
CC2530 chips restart operation.Reset circuit is as shown in Figure 6.
Audio playing circuit is designed
The voice data that audio playing circuit will be obtained from CC2530 modules, and then data are carried out after a series of processing
Clearly audio will be obtained to play out.Our department's parallel circuit is amplified to the audio of input, and also there is device in circuit
Caused noise, if not handling noise, the sound that input microphone is sent will be by noise takeover, so will
Necessary filtering process is carried out to signal.Audio playing circuit schematic diagram is as shown in Figure 7.
Audio playing circuit is designed, and power amplification is carried out to signal from LM386, and the voltage ratio of LM386 work is relatively low, 4V
Direct power supply can just meet its work, it is possible to and audio collection circuit and audio playing circuit one power supply mould of work
Block, it is not necessary to redesign new power module.The gain of LM386 built-in voltages be 20, but also beat less than amplification multiple will
Ask, it is necessary to which external 10uF electric capacity makes voltage gain reach 200, electric capacity C4 size decision-making circuit between 1 pin and 8 pin
Multiplication factor.From the electric current output in 10K slide rheostat regulation circuit, by adjusting the resistance of slide rheostat,
The size of volume can be adjusted.The electric capacity C1 being connected with 7 pin is used as shunt capacitance, due to being mixed with high frequency and low in the signal of input
Frequency composition, C1 effect is exactly to filter out high-frequency components, it is ensured that low frequency signal is exported, and removes high-frequency noise.C2 capacitance sizes are selected
250uF, for blocking and coupling, powers, its pin of output end 5 can have DC voltage because LM386 is single supply for it, if
DC voltage exists speaker damage for a long time, because preventing passing through for DC voltage from 250uF C2, C2 can be with coupling
The AC signal in circuit is closed, electric capacity C2 constitutes single order high-pass filter with loudspeaker, input signal is filtered, can
To reduce noise.
LM386 power amplifiers are all used in audio collection and playing circuit, LM386 power amplifier effect is to processing audio
Amplification effect is very good, is a kind of integrated circuit dedicated for audio frequency power amplifier.There is three-stage amplifier inside the amplifier,
So the good results are evident for amplification.The amplifier has eight pins, and pin 2 and 3 is respectively anti-phase and in-phase input end, with drawing
Pin 5 is exported to signal, the electric capacity of the indirect control multiplication factor of octal and a pin, if a not external electric capacity
Words, the voltage gain of circuit only has 20, and four pin are used to be grounded, and six pin are used to be connected to its power supply with 5V power supply, and pin 7 is grounded
Necessary additional 0.1uF shunt capacitance, can effectively suppress noise before.LM386 can also be powered with battery, power dissipation ratio
It is relatively low.
LM393 devices are used in audio collection circuit, LM393 is the twin voltage comparator integrated circuit of specialty.LM393
Built-in two comparators are used for the comparison of two ends input voltage, the two ends input analog signal of each comparator, to this two sections
Voltage is compared, and high level is output as in the case that the voltage of in-phase end is high, if anti-phase terminal voltage is then output as when high
Low level, LM393 can be used as analog circuit and the interface of digital circuit.LM393 pin 1, pin 2 and pin 3 is respectively one
Output end, inverting input and the normal phase input end of individual comparator.Pin 4 and pin 8 are respectively used to be grounded and connect electricity, its excess-three
Individual pin is as separately with the input and output side of individual comparator.LM393 can be removed or be reduced the shake in circuit using hysteresis
Swing, these concussions are it is usually because output end has parasitic capacitance to input, and these parasitic capacitances cause concussion, and this shake
It is also to eliminate to swing i.e. around power supply using filter capacitor.
Power supply unit is designed
The power supply unit is powered using battery or dc source is powered, as shown in Figure 8.6V voltage passes through 4
Section 1.5V battery is realized by battery pack, but CC2530 needs 3.3V voltage, so the design is used
AMS1117 come carry out magnitude of voltage 6 arrive 3.3V conversion.There is direct current supply mode in addition, dc source, which is powered, directly exports 5V
Voltage, is then converted directly into 3.3V voltages by AMS1117 chips by 5V voltages.It can select what power supply was selected by switch
Mode.When testing out of doors battery must be used to power could ensure the normal operation of node.
As shown in figure 9, the function of AMS1117 conversion circuit modules is to realize that the 6V voltages for providing battery pack pass through
AMS1117 fixed voltage output function obtains 3.3V voltage, with this 3.3V voltage gives CC2530 chip power supplies.
There are special USB interface and DC interfaces to be used to power on the base of CC2530 modules, while base can also be to adopt
Collector and playing circuit are powered, and from left to right three buttons of base lower left are that S1 and S2 can manual networking, S3 use respectively
In circuit reset.It is row's indicator lamp above button, first three is networking indicator lamp, RX and TX are serial ports transmitting-receiving indicator lamps,
PWR is power supply indicator.
Described above is only the preferred embodiment of the present invention, it is noted that for the ordinary skill people of the art
For member, under the premise without departing from the principles of the invention, some improvements and modifications can also be made, these improvements and modifications also should
It is considered as protection scope of the present invention.
Claims (6)
1. the wireless audio transmission system based on ZigBee, it is characterised in that including
Audio collection unit, using the audio sensor being made up of microphone, audio collection circuit, for gathering voice data；
Audio transmission unit, using CC2530 chips, the 8051CPU for being carried by CC2530 is adopted audio collection unit
Collect voice data and carry out analog-to-digital conversion, the data signal that machine can be recognized is converted analog signals into, by software section pair
The voice data collected is carried out after coding compression, and data are wirelessly sent into audio using CC2530 wireless transceiver plays
Unit；
Audio playing unit, for receiving the data come by CC2530 transmitter wireless transmissions, and is entered by filter circuit
It is connected to after row denoising, then after being amplified by amplifying circuit on loudspeaker, realizes the broadcasting of audio；
Power supply unit, for providing voltage output to audio collection, transmission and playing module, it is ensured that having for each module is steady
Fixed voltage supply.
2. the wireless audio transmission system as claimed in claim 1 based on ZigBee, it is characterised in that the audio is played single
Member selects 0.8 Ω power 0.5W loudspeaker.
3. the wireless audio transmission system as claimed in claim 1 based on ZigBee, it is characterised in that the audio collection electricity
It route MIC microphones, resistance, electric capacity, amplifier to constitute, audio carries out current limliting from MIC microphone inputs by 10K R1,
VCC is powered using extraneous 4-8V dc sources.C1 uses electric capacity 104 as coupled capacitor, by shunt capacitance C3 by before
High and low frequency signal in level circuit is separated, and is filtered out the high-frequency noise in input signal, is passed through C4 electric capacity 10uF control pair
200 times of voltage amplification, is used using electric capacity 220uF C6 as output coupling, separates the direct current of DC voltage and coupling audio
Signal, the electric capacity C7 power supply sources filtering from 470uF is used, and removes the noise of power pin, and stable IC power supply, electric capacity C8 is steady
Determine power supply output；Signal amplification is carried out to voltage in circuit from LM386 power amplifiers, can be changed by the size for changing C4
Become multiplication factor, from twin voltage comparator integrated circuit, pin 2 and the input analog signal of pin 3, pin 1 then export two and entered
The data signal of system, audio signal will be output to CC2530 I/O mouths after amplification and filtering process.
4. the wireless audio transmission system as claimed in claim 1 based on ZigBee, it is characterised in that the audio transmission list
Member includes CC2530 chips, module interface base and reset circuit, and the CC2530 chips carry 8051CPU processors and radio frequency
Transceiver, each interface of module interface base is all connected to CC2530 modules each pins accordingly, so as to allow power supply
Voltage, sensor signal and reset signal enter in correct CC2530 chip pins, complete to CC2530 chip power supplies, signal
Collection and reset operation；The low level that reset circuit is produced is input to a CC2530 reset pin, performs a series of hard
Part initialization operation, including：21 I/O pins are all configured to input pull-up by CC2530 chips；0x0000 address assignments
To CC2530 CPU program pointers, program is performed since 0x0000 addresses；All peripheral hardware registers of CC2530 chips are initial
Reset values are turned to, after completing to reset, CC2530 chips restart operation.
5. the wireless audio transmission system as claimed in claim 1 based on ZigBee, it is characterised in that CC2530 antenna is adopted
With the flagpole antenna of 2db SMA interfaces.
6. the wireless audio transmission system as claimed in claim 1 based on ZigBee, it is characterised in that the power supply supply is single
Member is powered using battery or dc source is powered.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201710579625.1A CN107295444A (en) | 2017-07-13 | 2017-07-13 | Wireless audio transmission system based on ZigBee |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201710579625.1A CN107295444A (en) | 2017-07-13 | 2017-07-13 | Wireless audio transmission system based on ZigBee |
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| CN107295444A true CN107295444A (en) | 2017-10-24 |
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| CN201710579625.1A Pending CN107295444A (en) | 2017-07-13 | 2017-07-13 | Wireless audio transmission system based on ZigBee |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115508649A (en) * | 2022-10-12 | 2022-12-23 | 广东浩博特科技股份有限公司 | Darkroom acousto-optic test system |
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| CN201789596U (en) * | 2010-09-08 | 2011-04-06 | 山东科技大学 | Wireless audio transmission system |
| CN103313435A (en) * | 2012-03-08 | 2013-09-18 | 上海阅维信息科技有限公司 | Wireless audio system of multipath voice centralized transmission |
| CN103763736A (en) * | 2014-01-15 | 2014-04-30 | 中煤矿山建设集团有限责任公司 | Wireless real-time high-quality voice transmission device and method based on ZigBee technology |
| CN105208680A (en) * | 2014-06-10 | 2015-12-30 | 王中生 | Method for audio data transmission based on short-range wireless sensing network |
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2017
- 2017-07-13 CN CN201710579625.1A patent/CN107295444A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201789596U (en) * | 2010-09-08 | 2011-04-06 | 山东科技大学 | Wireless audio transmission system |
| CN103313435A (en) * | 2012-03-08 | 2013-09-18 | 上海阅维信息科技有限公司 | Wireless audio system of multipath voice centralized transmission |
| CN103763736A (en) * | 2014-01-15 | 2014-04-30 | 中煤矿山建设集团有限责任公司 | Wireless real-time high-quality voice transmission device and method based on ZigBee technology |
| CN105208680A (en) * | 2014-06-10 | 2015-12-30 | 王中生 | Method for audio data transmission based on short-range wireless sensing network |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115508649A (en) * | 2022-10-12 | 2022-12-23 | 广东浩博特科技股份有限公司 | Darkroom acousto-optic test system |
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Application publication date: 20171024 |
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