CN208635912U

CN208635912U - A kind of noise detecting circuit of RC weighted

Info

Publication number: CN208635912U
Application number: CN201821415627.3U
Authority: CN
Inventors: 王正飞; 张国俊; 李晓
Original assignee: Chongqing Dangle Technology Co Ltd
Current assignee: Chongqing Dangle Technology Co Ltd
Priority date: 2018-08-30
Filing date: 2018-08-30
Publication date: 2019-03-22
Anticipated expiration: 2028-08-30

Abstract

The utility model discloses a kind of noise detecting circuit of RC weighted, including Noise Acquisition module, signal amplification module and weighted module, by voice signal input signal amplification module after the Noise Acquisition module collected sound signal, the signal amplification module will be transmitted to weighted module after voice signal enhanced processing, voice signal weighted processing after enhanced processing is obtained noise data by the weighted module, and the noise data is output to the receiving port of noise Rx equipment, the weighted module is made of capacitor and resistance.The utility model has the advantages that replacing weighted operation using hardware circuit, make voice signal that can be converted into the sound frequency closer to human ear impression by the circuit of hardware, software without redesigning complicated optimizes it, the acquisition noise of requirement when to reduce to(for) controller, achieve the purpose that accurately to measure noise, its advantage is that greatly reducing the requirement of controller operational performance and the complexity of software.

Description

A kind of noise detecting circuit of RC weighted

Technical field

The utility model relates to noise transducer technical fields, are a kind of noise detecting circuits of RC weighted specifically.

Background technique

It is several that noise testing generally comprises radio reception, piezoelectricity conversion, amplification, A/D sampling, FFT transform, weighted operation, calibration etc. A part, wherein radio reception, piezoelectricity conversion, amplification and A/D sampling belong to hardware circuit part, the works such as FFT transform, weighted and calibration Work is usually completed by software algorithm, and last noise data is obtained by control unit.

Radio reception partial function takes out ambient sound signal similar to the ear of people；Piezoelectricity conversion is to turn voice signal It is changed to the voltage signal or current signal that can carry out processing of circuit；Amplification circuits are that the electric signal after converting carries out Amplification filtering, to carry out subsequent processing；A/D sampling is that the analog signal of amplifying circuit output is converted to digital signal, is sent To control unit operation；FFT transform is that the signal after sampling is transformed into frequency domain by time domain, is convenient for weighted operation；Weighted Operation is to experience the different adjustment for needing to carry out amplitude to the voice signal of different frequency according to the ear of actual persons, so that measurement To sound amplitude more meet the practical impression of people；Calibration is that contrast standard is finely adjusted measurement result, improves its measurement Precision and accuracy；

The advantage and disadvantage of traditional measurement method: measurement result is accurately its biggest advantage, and disadvantage is then due to needing to carry out More complicated FFT transform and weighted algorithm generally require 16 even so the operational capability to control unit is more demanding 32 high-speed controllers are completed, while software algorithm is complex.

Utility model content

For the defect that above-mentioned FFT transform and weighted algorithm can only be completed by software, the utility model devises a kind of RC The noise detecting circuit of weighted replaces weighted operation using hardware circuit, convert voice signal can by the circuit of hardware For the sound frequency experienced closer to human ear, the software without redesigning complicated optimizes it, thus when reducing acquisition noise Requirement for controller achievees the purpose that accurately to measure noise, its advantage is that greatly reducing wanting for controller operational performance The complexity of summation software.

In order to achieve the above objectives, the specific technical solution that the utility model uses is as follows:

A kind of noise detecting circuit of RC weighted, including Noise Acquisition module, signal amplification module and weighted module, it is described By voice signal input signal amplification module after Noise Acquisition module collected sound signal, the signal amplification module believes sound Weighted module is transmitted to after number enhanced processing, the voice signal weighted processing after enhanced processing is obtained noise by the weighted module Data, and the noise data is output to the receiving port of noise Rx equipment, the weighted module is provided with main RC circuit；

The main RC circuit include the second capacitor C2, the output end of one end connection signal amplification module of second capacitor C2, The other end is sequentially connected in series the receiving port of connection noise Rx equipment after first capacitor C1,3rd resistor R3, second resistance R2；

Wherein, the second capacitor C2 is grounded after concatenating the second weighted resistance RC2 with the common end of first capacitor C1, described First capacitor C1 is grounded after concatenating the first weighted resistance RC1 with the common end of 3rd resistor R3, the 3rd resistor R3 and second The common end of resistance R2 is grounded after concatenating the 4th capacitor C4, the public affairs of the receiving port of the second resistance R2 and noise Rx equipment It is grounded after end concatenation third capacitor C3 altogether.

By above-mentioned design, voice signal is acquired and after amplifying, the weighted resume module signal that is formed by main RC circuit Excessively ear-piercing noise is converted the sound that frequency more meets human ear impression by frequency, other ginsengs without changing noise signal It counts, there was only resistance and capacitor in main RC circuit, and form the circuit structure of likeness in form filter circuit, can effectively convert the frequency of noise Rate, then the voice signal by the processing of above-mentioned weighted is just not required to carry out weighted processing with software again, but can directly select warp Noise signal after the weighted resume module is to follow-up processing flow, such as noise plays, noise decibel prompt, reduces control The requirement of device operational performance and the complexity of software.

Further design, the signal amplification module are provided with two-stage amplifying circuit, including first order amplifying circuit and the Second amplifying circuit, the audio signal output terminal of the input terminal connection Noise Acquisition module of the first order amplifying circuit are described Amplified signal output end of the input terminal connection first order amplifying circuit of second level amplifying circuit；

The secondary amplified signal output end of the second level amplifying circuit connects the main RC circuit of the weighted module, described Amplified signal output end of first order amplifying circuit connects the secondary RC circuit of the weighted module, the circuit of the secondary RC circuit Structure and device parameters and the main RC circuit are completely the same, and the two is attempted by the signal amplification module and sets with noise Rx Between standby；

Wherein, the secondary amplified signal output end of the input terminal connection signal amplification module of main RC circuit, main RC circuit The secondary amplification noise Rx port ANOISE1 of output end connection noise Rx equipment；

Amplified signal output end of the input terminal connection signal amplification module of secondary RC circuit, the output end of secondary RC circuit Connect the primary amplification noise Rx port ANOISE2 of noise Rx equipment.

Since the decibel size of noise is indefinite, when noise is larger, there is no need to excessive enhanced processings, and noise is smaller When just need bigger amplification factor, therefore two-stage amplifying circuit is provided in above-mentioned design, biggish noise signal passes through the Level-one amplifying circuit can directly acquire data, and lesser noise signal also needs to carry out two to it by second level amplifying circuit Secondary amplification, and an amplified signal output end of two-stage amplifying circuit and secondary amplified signal output end are connected separately with a RC Circuit, is main RC circuit and secondary RC circuit respectively, and the circuit structure and device parameters of two RC circuits are completely the same, in this way regardless of The amplitude size of noise signal all can make sound that can adapt to by identical frequency processing (i.e. the weighted processing of weighted module) The sensing capability of human ear, the noise signal by once amplifying and the noise signal through secondary amplification while being output to noise Rx Equipment only need to independently select the noise signal for needing which magnification level in subsequent processing, can obtain the noise needed Data, the influence by noise size to testing result are reduced to minimum.

Be further described, first capacitor C1 in the main RC circuit, the second capacitor C2, the 4th capacitor C4 capacitance be The capacitance of 1 μ F, the third capacitor C3 is 0.01 μ F；

The second resistance R2,3rd resistor R3 resistance value be 100 Ω, the first weighted resistance RC1, the second weighted The resistance value of resistance RC2 is 10K Ω.

Weighted processing by above-mentioned design is to be most suitable for the perception of common human ear, and noise signal is treated as most of People will not feel ear-piercing degree, can more be accepted by the public in the application field of noise measuring and alarm.

It is further described, the secondary RC circuit includes the tenth capacitor C10, the tenth one end capacitor C10 connection first Amplified signal output end of grade amplifying circuit, the other end are sequentially connected in series the 9th capacitor C9, the 8th resistance R8, the 7th resistance R7 The primary amplification noise Rx port ANOISE2 of noise Rx equipment is connected afterwards；

Wherein, the tenth capacitor C10 is grounded after concatenating the 4th weighted resistance RC4 with the common end of the 9th capacitor C9, institute It states after the 9th capacitor C9 concatenates third weighted resistance RC3 with the common end of the 8th resistance R8 and is grounded, the 8th resistance R8 and The common end of seven resistance R7 is grounded after concatenating the 13rd capacitor C13, and the 7th resistance R7 is once put with noise Rx equipment The common end of big noise Rx port ANOISE2 is grounded after concatenating the 12nd capacitor C12.

The design of secondary RC circuit and main RC circuit are completely the same, and exporting the noise signal of first order amplifying circuit can also count Power processing after be sent to noise Rx equipment, to script noise signal with regard to it is bigger, without big multiple amplification is carried out to it again Noise measuring situation, can only amplify and once just be directly connected to noise Rx equipment.

Further design, the signal amplification module include two-stage amplification chip U1, and the one of two-stage amplification chip U1 The first differential signal input pin-INA of grade connects Noise Acquisition module after being sequentially connected in series the 9th resistance R9, the 11st capacitor C11 Level-one the second differential signal input pin+INA of second noise signal output end Output+, the two-stage amplification chip U1 is successively The first noise signal output end Output- that Noise Acquisition module is connected after the 6th resistance R6, the 5th capacitor C5 is concatenated, this first The 6th capacitor C6 is serially connected between noise signal output end Output- and the second noise signal output end Output+；

Second level is connected after the amplified signal output end OutA concatenation eleventh resistor R11 of the two-stage amplification chip U1 Second level the first differential signal input pin-INB concatenation first of second differential signal input pin+INB, the two-stage amplification chip U1 It is grounded after resistance R1；

The tenth is serially connected between amplified signal output end OutA and level-one the first differential signal input pin-INA Resistance R10, is serially connected with the 4th between the secondary amplified signal output end OutB and second level the first differential signal input pin-INB It is grounded after resistance R4, the 5th resistance R5 of level-one the second differential signal input pin+INA concatenation, the second difference of second level letter It is grounded after number input pin+INB concatenation twelfth resistor R12；

The positive pole V+ of the two-stage amplification chip U1 connects 5V voltage, power cathode ground connection.

By above-mentioned design, every level-one amplifying circuit all pass through input two signals calculate its difference situation to input signal It amplifying, two input signals of first order amplifying circuit are two output signals of Noise Acquisition module respectively, and second One of input signal of grade amplifying circuit is the output signal of first order amplifying circuit, another input signal is then ground connection Low level, the differential signal of Noise Acquisition module can be through secondary RC circuit weighted input noise after the amplification of first order amplifying circuit Receiving device, the noise signal of first order amplifying circuit amplification also input second level amplifying circuit and carry out secondary amplification, Zhi Houzai Through main RC circuit weighted input noise receiving device, the noise signal of the noise signal once amplified and secondary amplification can be counted Input noise receiving device after power.

Further design, the resistance value of the first resistor R1, the 6th resistance R6, the 9th resistance R9, eleventh resistor R11 Be 1K Ω, the 5th resistance R5, the tenth resistance R10 resistance value be 10K Ω, the 4th resistance R4, twelfth resistor The resistance value of R12 is 470K Ω；

The 5th capacitor C5, the 11st capacitor C11 capacitance be 1 μ F, the capacitance of the 6th capacitor C6 is 270pF。

Further design, the Noise Acquisition module includes microphone chip U2, the model of microphone chip U2 MP23AB01DH, 2 feet are the first noise signal output end Output-, and 3 feet are the second noise signal output end Output+, should Be serially connected between the power end VDD and lower margin GND of microphone chip U2 the 7th capacitor C7, the power end VDD and lower margin GND it Between be also serially connected with the 8th capacitor C8；

The power end VDD connection 3.3V voltage, lower margin GND ground connection.

By above-mentioned design, the module of radio reception is integrated on microphone chip U2, the data of radio reception pass through 2 feet and 3 feet It is output to first order amplifying circuit.

The capacitance of the 7th capacitor C7 is 1 μ F, and the capacitance of the 8th capacitor C8 is 1000pF.

Further design, further includes voltage regulating module, which includes pressure regulation chip U3, the pressure regulation chip U3's Input pin IN connection 5V voltage, output pin OUT then export 3.3V voltage；

It is serially connected with the 15th capacitor C15 between the input pin IN and grounding leg GND of the pressure regulation chip U3, input pin IN The 14th capacitor C14 is also serially connected between grounding leg GND.

By above-mentioned design, 5V voltage only need to be inputted, 3.3V voltage and signal needed for providing for Noise Acquisition module 5V voltage needed for amplification module.

The capacitance of the 14th capacitor C14 is 1000pF, and the capacitance of the 15th capacitor C15 is 10 μ F.

The utility model has the beneficial effects that replacing weighted operation using hardware circuit, make electricity of the voice signal by hardware Road can be converted into the sound frequency closer to human ear impression, and the software without redesigning complicated optimizes it, to reduce The noise of requirement when acquiring to(for) controller, achievees the purpose that accurately to measure noise, its advantage is that greatly reducing controller fortune Calculate the requirement of performance and the complexity of software.

Detailed description of the invention

Fig. 1 is the structural schematic diagram of the utility model；

Fig. 2 is the circuit design drawing of main RC circuit；

Fig. 3 is the structural block diagram of embodiment；

Fig. 4 is the circuit design drawing of embodiment；

Fig. 5 is the circuit design drawing of embodiment voltage regulating module；

Fig. 6 is a kind of three-dimensional structure diagram of circumstance video monitoring case with noise measuring；

Fig. 7 is the internal structure chart of environmental monitoring case；

Fig. 8 is the structure chart of circuit mounting plate；

Fig. 9 is the structure chart of apparatus mounting plate；

Figure 10 is the chart at the bottom of of cabinet；

Figure 11 is the circuit diagram of power-supply device.

Specific embodiment

With reference to the accompanying drawing and specific embodiment is described in further detail the utility model:

As shown in Figure 1, a kind of noise detecting circuit of RC weighted, including Noise Acquisition module 3,2 and of signal amplification module Weighted module 1, by voice signal input signal amplification module 2, the signal after 3 collected sound signal of Noise Acquisition module Amplification module 2 will be transmitted to weighted module 1 after voice signal enhanced processing, the weighted module 1 is by the sound after enhanced processing The processing of signal weighted obtains noise data, and the noise data is output to the receiving port of noise Rx equipment, the weighted Module 1 is provided with main RC circuit 1a.

Main RC circuit 1a as shown in Figure 2 includes the second capacitor C2, and one end connection signal of second capacitor C2 amplifies mould The output end of block 2, the other end connect noise Rx equipment after being sequentially connected in series first capacitor C1,3rd resistor R3, second resistance R2 Receiving port；

Preferably, first capacitor C1 in the main RC circuit 1a, the second capacitor C2, the 4th capacitor C4 capacitance be 1 μ F, The capacitance of the third capacitor C3 is 0.01 μ F；

Preferred embodiment is as shown in figure 3, the signal amplification module 2 is provided with two-stage amplifying circuit, including first Grade amplifying circuit and second level amplifying circuit, the sound of the input terminal connection Noise Acquisition module 3 of the first order amplifying circuit Signal output end, an amplified signal output end of the input terminal connection first order amplifying circuit of the second level amplifying circuit；

The secondary amplified signal output end of the second level amplifying circuit connects the main RC circuit 1a of the weighted module 1, Amplified signal output end of the first order amplifying circuit connects secondary RC circuit 1b, the secondary RC electricity of the weighted module 1 The circuit structure and device parameters of road 1b and the main RC circuit 1a are completely the same, and the two is attempted by the signal amplification module Between 2 and noise Rx equipment；

Wherein, the secondary amplified signal output end of the input terminal connection signal amplification module 2 of main RC circuit 1a, main RC circuit The secondary amplification noise Rx port ANOISE1 of the output end connection noise Rx equipment of 1a；

Amplified signal output end of the input terminal connection signal amplification module 2 of secondary RC circuit 1b, secondary RC circuit 1b's The primary amplification noise Rx port ANOISE2 of output end connection noise Rx equipment.

As shown in figure 4, the secondary RC circuit 1b includes the tenth capacitor C10, described tenth one end capacitor C10 connects the first order Amplified signal output end of amplifying circuit, after the other end is sequentially connected in series the 9th capacitor C9, the 8th resistance R8, the 7th resistance R7 Connect the primary amplification noise Rx port ANOISE2 of noise Rx equipment；

9th capacitor C9 in the secondary RC circuit 1b, the tenth capacitor C10, the 13rd capacitor C13 capacitance be 1 μ F, institute The capacitance for stating the 12nd capacitor C12 is 0.01 μ F；

The 7th resistance R7, the 8th resistance R8 resistance value be 100 Ω, the third weighted resistance RC3, the 4th weighted The resistance value of resistance RC4 is 10K Ω.

Signal amplification module 2 described in the embodiment includes two-stage amplification chip U1, the level-one of two-stage amplification chip U1 First differential signal input pin-INA, which is sequentially connected in series, connects the of Noise Acquisition module 3 after the 9th resistance R9, the 11st capacitor C11 Level-one the second differential signal input pin+INA of two noise signal output end Output+, the two-stage amplification chip U1 successively goes here and there The first noise signal output end Output- that Noise Acquisition module 3 is connected after the 6th resistance R6, the 5th capacitor C5 is met, this first The 6th capacitor C6 is serially connected between noise signal output end Output- and the second noise signal output end Output+；

Preferably, the resistance value of the first resistor R1, the 6th resistance R6, the 9th resistance R9, eleventh resistor R11 are 1K Ω, the 5th resistance R5, the tenth resistance R10 resistance value be 10K Ω, the 4th resistance R4, twelfth resistor R12 Resistance value is 470K Ω；

Preferably the Noise Acquisition module 3 includes microphone chip U2, the model of microphone chip U2 to the present embodiment For MP23AB01DH, 2 feet are the first noise signal output end Output-, and 3 feet are the second noise signal output end Output+, The 7th capacitor C7, the power end VDD and lower margin GND are serially connected between the power end VDD and lower margin GND of microphone chip U2 Between be also serially connected with the 8th capacitor C8；

The power end VDD connection 3.3V voltage, lower margin GND ground connection.

The capacitance of the 7th capacitor C7 is preferably 1 μ F, and the capacitance of the 8th capacitor C8 is preferably 1000pF.

As shown in figure 5, the present embodiment further includes voltage regulating module 4, which includes pressure regulation chip U3, the pressure regulation The input pin IN connection 5V voltage of chip U3, output pin OUT then export 3.3V voltage；

The capacitance of the 14th capacitor C14 is preferably 1000pF, and the capacitance of the 15th capacitor C15 is preferably 10 μ F。

The scene that the present embodiment is preferably applied is that monitoring device is detected in building site, as shown in FIG. 6 a kind of with noise measuring Circumstance video monitoring case, including environmental monitoring case 5, video living transmission system 6, video living transmission system 6 includes video camera 61 and aobvious Display screen 62 is respectively provided on the chamber door 53 of the environmental monitoring case 5 and places window 51 and camera shooting head bore 52, the environmental monitoring It is provided with circuit mounting plate 7 and apparatus mounting plate 8 in case 5, display screen 62 is installed on circuit mounting plate 7,62 face of display screen is put Window 51 is set, is fixed with placement platform 81 on the apparatus mounting plate 8, video camera 61 is placed on the placement platform 81, is imaged Head bore 52 is imaged described in the camera face of machine 61；

As shown in fig. 7, the apparatus mounting plate 8 is equipped with the noise detecting circuit 11 of the utility model, noise measuring electricity The data on road 11 are exported through signal output cable 94.

It is additionally provided with lockhole 531 on the chamber door 53, the lockhole 531 is for installing lock, the side of chamber door 53 and cabinet 54 It is connected by a hinge, the other side passes through lock connection.

It is advantageous in that by above-mentioned design, by the placement window 51 it can be seen that the display screen of video living transmission system 6 62 compare with other environmental monitoring casees, which is to show the ambient video information of region, pass through display screen 62 are broadcast live, and simultaneous camera 61 is also equipped with video output interface, and video output interface can be connected by connecting cable To administrative department, facilitates administrative department to the real time monitoring of environment, realize human-computer interaction.Described in camera acquisition using placement The external environment of environmental monitoring case.Window 51, the circuit mounting plate 7 are placed described in the front end face face of the circuit mounting plate 7 Front end face on display screen 62 is installed, facilitate the personnel outside monitoring box to watch in real time.It is fixed on the apparatus mounting plate 8 The placement platform 81 of video camera 61 is assembled, which is in the inside of the environmental monitoring case 5, with other environmental monitorings Case is compared, so that entire cabinet external structure becomes succinctly, to reduce corrosion of the external environment to video camera 61, the placement platform 81 Head bore 52 is imaged described in the camera face of the video camera 61 of upper placement, and camera is facilitated to shoot real-time pictures.

The signal output cable 94 is by 2mm²Cable be made, the signal output cable 94 be helical form.

2mm²Cable strength it is enough, connection is reliable, and signal output cable 94, which is set as helical form, arbitrarily to be stretched, side Just the sound detection signals of noise detecting circuit 11 are drawn, is connected to the acquisition module of industrial personal computer.

As shown in Figure 10, the environmental monitoring case 5 is rectangle, and the left and right sides of the cabinet 54 of the environmental monitoring case 5 are opened There is shutter 55, downward, the downside of cabinet 54 offers ventilation hole array 56 to the window of the shutter 55.

By above-mentioned design, shutter 55 is that the environmental monitoring case 5 provides ventilation and heat, and internal sensor is dissipated External environment data are also obtained while hot.Downward, window purpose directed downwardly is prevented in rainy day environment to 55 window of shutter Under there is water droplet to enter the environmental monitoring case 5 inside, it is ensured that the normal operation of internal unit.The ventilation hole array 56 is The lower part of the environmental monitoring case 5 provides heat dissipation ventilation, increases ventilation quantity.

The circuit mounting plate 7 is located at the top of the environmental monitoring case 5, which forms vertical Plate 71 has two ventilation holes 72 as shown in figure 8, the vertical plate 71 is fixed on the bottom surface of the cabinet 54 on vertical plate 71, It is provided with route mouth 73 among two ventilation holes 72 of the vertical plate 71 in the left side, is placed between the vertical plate 71 of the left and right sides described The power-supply device 57 of environmental monitoring case 5.

By above-mentioned design, before the display screen 62 of the video living transmission system 6 in the case is mounted on the circuit mounting plate 7 On end face, so that display screen 62 is in environmental monitoring case 5, the service life of display screen 62 can be extended.Placing window 51 can Transparent panel is set；72 purpose of ventilation hole is to increase ventilation quantity, provides rapid cooling, the route mouth for circuit mounting plate 7 73 be the wire inlet/outlet hole of power-supply device 57, and power-supply device 57 is that entire environmental monitoring case 5 is powered.

As shown in figure 11, the power-supply device 57 is provided with AC socket J2, and the zero line of AC socket J2 connects fusing The other end of one end of device F1, one end of the other end connection switch S1 of fuse F1, switch S1 connects IRM60-5 power module Zero line, IRM60-5 power module zero line side connection AC socket J2 zero line side, AC socket J2 ground terminal ground connection； The anode of the positive output end connection electrolytic capacitor E1 of IRM60-5 power module, the cathode of electrolytic capacitor E1 connect IRM60-5 power supply The negative output terminal of module, the negative output terminal ground connection of IRM60-5 power module；The positive output end of IRM60-5 power module exports 5V DC voltage；

The positive output end of IRM60-5 power module is also connected with the input terminal of AMS1117-3.3 power module, AMS1117- The ground terminal of 3.3 power modules is grounded, and the output end of AMS1117-3.3 power module exports 3.3V DC voltage；

The other end of switch S1 is also connected with the zero line of IRM60-12 power module, the zero line side of IRM60-12 power module Connect the zero line side of AC socket J2；The anode of the positive output end connection electrolytic capacitor E2 of IRM60-12 power module, electrolysis electricity Hold the negative output terminal of the cathode connection IRM60-12 power module of E2, the negative output terminal ground connection of IRM60-12 power module； The positive output end of IRM60-12 power module exports 12V DC voltage.

It is arranged by the circuit of above-mentioned power-supply device 57, can is video camera 61, the display screen inside environmental monitoring case 5 62, noise detecting circuit 11 and other equipment provide 5V, 3.3V, 12V DC voltage, and the structure of circuit is simple.

The apparatus mounting plate 8 is located at the lower part of the environmental monitoring case 5, the left and right sides folding of the apparatus mounting plate 8 Bending is at support plate 82, as shown in figure 9, support plate 82 is fixedly connected with the bottom of the cabinet 54, it is also solid on apparatus mounting plate 8 Surely there is lower vertical plate 83, the lamp hole 831 of installation signal lamp, the 831 frontage and airiness hole of lamp hole battle array are provided on the lower vertical plate 83 Noise detecting circuit 11 is arranged in the front end face of column 56, apparatus mounting plate 8.

By above-mentioned design, it is provided with lamp hole 831, facilitates installation signal lamp, signal lamp is used to indicate described The working condition of environmental monitoring case, the lamp hole 831 is close and towards the ventilation hole array 56, in order to pass through the ventilation 56 observation signal indicator light of hole array.The front end face of apparatus mounting plate 8 facilitates installation noise detecting circuit 11.

54 bottom of cabinet is provided with cable-through hole 58, and 58 surrounding of cable-through hole is uniformly distributed that there are four screw holes 59.

By above-mentioned design, cable-through hole 58 facilitates to introduce the cable of environmental monitoring case 5 and draw, for example signal is exported electricity Cable 94 is drawn.The vision signal of video camera 61 is drawn.

Wherein, temperature sensor, humidity sensor, smoke sensor device, air pressure sensing can also be set in environmental monitoring case 5 Device, height above sea level sensor, PM2.5 sensor, the sensor are all set on the front end face of apparatus mounting plate 8；

Industrial personal computer and acquisition module can be set in outside environmental monitoring case 5, and noise detecting circuit 11 exports electricity by signal Cable 94 connects acquisition module, also can be set in the receiving in environmental monitoring case 5, between the vertical plate 71 of 7 two sides of circuit mounting plate Space can also install industrial personal computer and acquisition module other than it can accommodate power-supply device 57.

Industrial personal computer connection interchanger and fiber optical transceiver can be set in outside environmental monitoring case 5, also can be set in In environmental monitoring case 5, interchanger is sent after obtaining the environmental parameter signals that industrial personal computer acquires by fiber optical transceiver connection optical fiber Into server.Accommodation space between the left and right sides support plate 82 of the apparatus mounting plate 8 can be used for accommodating interchanger And fiber optical transceiver.

Signal lamp can be used for power module 57, video camera 61, display screen 62 and other such as industrial personal computers, acquisition The work instruction of module, sensor module.

Claims

1. a kind of noise detecting circuit of RC weighted, including Noise Acquisition module (3), signal amplification module (2) and weighted module (1), by voice signal input signal amplification module (2) after Noise Acquisition module (3) collected sound signal, the signal is put Big module (2) will be transmitted to weighted module (1) after voice signal enhanced processing, and the weighted module (1) will be after enhanced processing The processing of voice signal weighted obtains noise data, and the noise data is output to the receiving port of noise Rx equipment, special Sign is: the weighted module (1) is provided with main RC circuit (1a)；

The main RC circuit (1a) includes the second capacitor C2, the output of one end connection signal amplification module (2) of second capacitor C2 End, the other end are sequentially connected in series the receiving end of connection noise Rx equipment after first capacitor C1,3rd resistor R3, second resistance R2 Mouthful；

Wherein, the second capacitor C2 is grounded after concatenating the second weighted resistance RC2 with the common end of first capacitor C1, and described first Capacitor C1 is grounded after concatenating the first weighted resistance RC1 with the common end of 3rd resistor R3, the 3rd resistor R3 and second resistance The common end of R2 is grounded after concatenating the 4th capacitor C4, the common end of the receiving port of the second resistance R2 and noise Rx equipment It is grounded after concatenation third capacitor C3.

2. a kind of noise detecting circuit of RC weighted according to claim 1, it is characterised in that: the signal amplification module (2) it is provided with two-stage amplifying circuit, including first order amplifying circuit and second level amplifying circuit, the first order amplifying circuit Input terminal connects the audio signal output terminal of Noise Acquisition module (3), the input terminal connection first of the second level amplifying circuit Amplified signal output end of grade amplifying circuit；

The secondary amplified signal output end of the second level amplifying circuit connects the main RC circuit (1a) of the weighted module (1), Amplified signal output end of the first order amplifying circuit connects the secondary RC circuit (1b) of the weighted module (1), the pair The circuit structure and device parameters of RC circuit (1b) and the main RC circuit (1a) are completely the same, and the two is attempted by the signal Between amplification module (2) and noise Rx equipment；

Wherein, the secondary amplified signal output end of the input terminal connection signal amplification module (2) of main RC circuit (1a), main RC circuit The secondary amplification noise Rx port ANOISE1 of the output end connection noise Rx equipment of (1a)；

Amplified signal output end of the input terminal connection signal amplification module (2) of secondary RC circuit (1b), secondary RC circuit (1b) Output end connection noise Rx equipment primary amplification noise Rx port ANOISE2.

3. a kind of noise detecting circuit of RC weighted according to claim 2, it is characterised in that: in the main RC circuit (1a) First capacitor C1, the second capacitor C2, the 4th capacitor C4 capacitance be 1 μ F, the capacitance of the third capacitor C3 is 0.01 μ F；

The second resistance R2,3rd resistor R3 resistance value be 100 Ω, the first weighted resistance RC1, the second weighted resistance The resistance value of RC2 is 10K Ω.

4. a kind of noise detecting circuit of RC weighted according to Claims 2 or 3, it is characterised in that: the secondary RC circuit (1b) includes the tenth capacitor C10, the amplified signal output of the tenth one end capacitor C10 connection first order amplifying circuit End, the other end are sequentially connected in series the primary amplification of connection noise Rx equipment after the 9th capacitor C9, the 8th resistance R8, the 7th resistance R7 Noise Rx port ANOISE2；

Wherein, the tenth capacitor C10 is grounded after concatenating the 4th weighted resistance RC4 with the common end of the 9th capacitor C9, and described Nine capacitor C9 are grounded after concatenating third weighted resistance RC3 with the common end of the 8th resistance R8, the electricity of the 8th resistance R8 and the 7th The common end of resistance R7 is grounded after concatenating the 13rd capacitor C13, and the 7th resistance R7 and the primary amplification of noise Rx equipment are made an uproar The common end of sound reception port ANOISE2 is grounded after concatenating the 12nd capacitor C12.

5. a kind of noise detecting circuit of RC weighted according to Claims 2 or 3, it is characterised in that: the signal amplifies mould Block (2) includes two-stage amplification chip U1, and level-one the first differential signal input pin-INA of two-stage amplification chip U1 is sequentially connected in series The second noise signal output end Output+ of Noise Acquisition module (3) is connected after 9th resistance R9, the 11st capacitor C11, it is described Level-one the second differential signal input pin+INA of two-stage amplification chip U1 is connected after being sequentially connected in series the 6th resistance R6, the 5th capacitor C5 First noise signal output end Output- of Noise Acquisition module (3), the first noise signal output end Output- and second The 6th capacitor C6 is serially connected between noise signal output end Output+；

Second level second is connected after the amplified signal output end OutA concatenation eleventh resistor R11 of the two-stage amplification chip U1 Second level the first differential signal input pin-INB of differential signal input pin+INB, the two-stage amplification chip U1 concatenate first resistor It is grounded after R1；

The tenth resistance is serially connected between amplified signal output end OutA and level-one the first differential signal input pin-INA R10 is serially connected with the 4th resistance between the secondary amplified signal output end OutB and second level the first differential signal input pin-INB R4, level-one the second differential signal input pin+INA are grounded after concatenating the 5th resistance R5, and second differential signal of second level is defeated It is grounded after entering foot+INB concatenation twelfth resistor R12；

6. a kind of noise detecting circuit of RC weighted according to claim 5, it is characterised in that: the first resistor R1, Six resistance R6, the 9th resistance R9, eleventh resistor R11 resistance value be 1K Ω, the 5th resistance R5, the tenth resistance R10 Resistance value is 10K Ω, the 4th resistance R4, twelfth resistor R12 resistance value be 470K Ω；

The 5th capacitor C5, the 11st capacitor C11 capacitance be 1 μ F, the capacitance of the 6th capacitor C6 is 270pF.

7. a kind of noise detecting circuit of RC weighted according to claim 5, it is characterised in that: the Noise Acquisition module It (3) include microphone chip U2, the model MP23AB01DH of microphone chip U2,2 feet are the output of the first noise signal Hold Output-, 3 feet are the second noise signal output end Output+, the power end VDD and lower margin GND of microphone chip U2 it Between be serially connected with the 7th capacitor C7, be also serially connected with the 8th capacitor C8 between the power end VDD and lower margin GND；

The power end VDD connection 3.3V voltage, lower margin GND ground connection.

8. a kind of noise detecting circuit of RC weighted according to claim 7, it is characterised in that: the appearance of the 7th capacitor C7 The capacitance that value is 1 μ F, the 8th capacitor C8 is 1000pF.

9. a kind of noise detecting circuit of RC weighted according to claim 7, it is characterised in that: it further include voltage regulating module (4), The voltage regulating module (4) includes pressure regulation chip U3, and the input pin IN connection 5V voltage of the pressure regulation chip U3, output pin OUT is then Export 3.3V voltage；

Be serially connected with the 15th capacitor C15 between the input pin IN and grounding leg GND of the pressure regulation chip U3, input pin IN with connect The 14th capacitor C14 is also serially connected between lower margin GND.

10. a kind of noise detecting circuit of RC weighted according to claim 9, it is characterised in that: the 14th capacitor C14 Capacitance be 1000pF, the capacitance of the 15th capacitor C15 is 10 μ F.