Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with embodiment and accompanying drawing, the present invention is described in more detail.
Core concept of the present invention is: with the original communication information that transmitting terminal need transmit, be modulated to low frequency envelope high frequency analog signals, driving can be sent the audio frequency sound reflector that people's ear can hear and be sent the high frequency sound wave that is loaded with original communication information to receiving terminal; The high frequency sound wave that is loaded with original communication information that the receiver of receiving terminal will receive is converted to low frequency envelope high frequency analog signals earlier, restores original communication information again from low frequency envelope high frequency analog signals, thereby finishes ultrasonic communication.
Wherein, the various interactive informations between original communication information general reference different device, this interactive information comprises order and/or data, for example lteral data, video-audio data or guidance command.Therefore, the sound wave dispensing device can utilize the interactive information that carries in the high frequency sound wave, remote control sound wave receiving system.
The high frequency sound wave that is loaded with original communication information that transmitting terminal produces can be ultrasonic wave or class ultrasonic wave.Following examples all are example with the ultrasonic wave.The principle that employing class ultrasonic wave carries out communication is identical with the principle that the employing ultrasonic wave carries out communication.
Low frequency envelope high frequency analog signals belongs to high frequency carrier, adopts the low frequency envelope to carry original communication information.Fig. 1 is the example schematic of the high-frequency carrier signal of original communication information of the present invention and correspondence thereof.Original communication information among the present invention is generally the binary digit form.Fig. 1 shows when original communication information is " 010101010 ", the waveform of the high frequency carrier that it is corresponding.As seen, high frequency carrier is the high-frequency signal that is loaded with 1,0 digital information, represents " 1 " in the binary system with the high frequency waveforms with low frequency envelope, faces horizontal component between envelope mutually and represents " 0 " in the binary system.This is a kind of form of high frequency carrier, can adopt different high frequency carriers to represent original communication information according to different needs.
High frequency carrier shown in Fig. 1, its low frequency envelope has been selected the hexagon envelope for use.The rule that the low frequency envelope is chosen is: select to change comparatively mild nothing sudden change envelope.Envelope in the low frequency envelope high frequency carrier is the modulation signal that forms high frequency carrier, and such nothing sudden change envelope can reduce the influence of envelope variation to high frequency sound wave as far as possible after being modulated to high frequency carrier and being converted to high frequency sound wave.If modulation signal changes violent, for example in very short time, transfer high potential to or transfer electronegative potential to by high potential by electronegative potential, the high frequency sound wave after the modulation may change violent place at modulation signal and the appreciable noise of people's ear occur.For fear of this kind situation, the present invention can change original communication information into the milder low frequency envelope high frequency carrier of envelope variation.Make the present invention communication function to be integrated in the audio system smooth-goingly, can not produce the sound that people's ear can be heard because of the unexpected turnover of envelope.
Fig. 2 is several high frequency carrier schematic diagrames that optionally have the low frequency envelope of the present invention.As shown in Figure 2, the low frequency envelope can choose that (a) hexagon, (b) are oval, (c) round rectangle and (d) the linear figures of double-paraboloid, and the envelope of these envelopes is smooth, does not have sharp keen variation.All adopt hexagon as the low frequency envelope shape in embodiments of the present invention.
Fig. 3 is the embodiment of the invention one realizes communication based on ultrasonic wave an audio system composition structural representation.As shown in Figure 3, this system comprises dispensing device 100 and receiving system 110.
Wherein, dispensing device 100 comprises information modulating unit 102 and reflector 101.
Information modulating unit 102 is used to receive original communication information, should be modulated to low frequency envelope high frequency analog signals by original communication information, sends to reflector 101.
Reflector 101, the low frequency envelope high frequency analog signals that is used for being received from information modulating unit 102 is converted to audio signal, promptly carries the ultrasonic wave of original communication information, sends to receiving system 110.This reflector 101 adopts the device that generally can send the audio frequency sound that people's ear can hear can finish the conversion of analog signal to ultrasonic signal.When in existing audio system, integrating communication function, just can select for use to have the device that existing Speaker, buzzer etc. in the audio system can send the audio frequency sound that people's ear can hear now, as the reflector of ultrasonic communication.Here said existing audio system is to send the audio system of general sound.Should comprise audio frequency dispensing device that can send general sound and the apparatus for receiving audio that can receive general sound in the existing audio system.
Receiving system 110 comprises receiver 111 and information reverting unit 112.
Receiver 111 is used for the ultrasonic wave that is loaded with original communication information that transmission and reception apparatus 101 sends, and is converted into low frequency envelope high frequency analog signals, and sends to information reverting unit 112.This receiver 111 does not need to adopt special ultrasonic probe, ultrasonic receiver.In general, employing can be converted to the audio frequency sound that people's ear can be heard the device of analog signal.When in existing audio system, integrating communication function, just can select existing microphone in the audio system for use.
Information reverting unit 112 carries out the communication information reduction with the low frequency envelope high frequency analog signals that is received from receiver 111 and handles, and therefrom obtains original communication information.This information reverting unit 112 can adopt analog circuit to realize.
The audio system that realizes communication based on ultrasonic wave from above embodiment one as can be seen, the information modulating unit 102 shown in Fig. 3 is the key components that generate low frequency envelope high frequency analog signals.Information reverting unit 112 is the key components that obtain original communication information from the ultrasonic wave that is loaded with original communication information.Therefore, below information modulating unit 102 and information reverting unit 112 are elaborated.
Information modulating unit 102 can adopt accomplished in many ways, comprises software modulator approach and hardware modulator approach.Wherein adopt the software modulator approach to have low price, realize advantage easily; Adopt the hardware modulator approach to have fireballing advantage.
Fig. 4 is the composition structural representation of first kind of execution mode of information modulating unit among Fig. 3.This execution mode adopts the software modulator approach to realize the generation of low frequency envelope high frequency analog signals.As shown in Figure 4, the information modulating unit comprises that waveform generates control module and D/A converter module.
Wherein, waveform generates control module, is used to receive original communication information, is converted into low frequency envelope high-frequency digital signal, sends to D/A converter module.The control module that generates this waveform can adopt microprocessor to realize, is the software modulator approach therefore.
D/A converter module is used for being converted to low frequency envelope high frequency analog signals with being received from the low frequency envelope high-frequency digital signal of waveform generation control module, drives reflector 101.This D/A converter module can adopt digital-to-analogue conversion (D/A, Digital to Analog) circuit to realize.
Above-mentioned waveform generates control module and specifically comprises memory module, generation module and sending module.
Wherein, memory module is used to store the low frequency envelope high-frequency digital signal of original communication information correspondence; Return the low frequency envelope high-frequency digital signal of original communication information correspondence to generation module.This memory module can be stored the low frequency envelope parameters table of original communication information correspondence, this low frequency envelope parameters souvenir has carried original communication information, low frequency envelope high-frequency digital signal and the corresponding relation of the two, and the digital quantity of forming low frequency envelope high-frequency digital signal is the tabular value of low frequency envelope parameters table.In the embodiment of the invention, when original communication information is formed by 0 and 1, then memory module can only be stored the low frequency envelope parameters table of 0 and 1 correspondence.
Generation module is used to receive original communication information, obtains the low frequency envelope high-frequency digital signal of this original communication information correspondence from memory module, sends to sending module.When obtain from memory module be the low frequency envelope parameters table of original communication information correspondence the time, then this low frequency envelope parameters table is sent to sending module.
Sending module is used to receive the low frequency envelope high-frequency digital signal that generation module sends, and sends to D/A converter module.When be received from generation module be low frequency envelope parameters table the time, this sending module sends to D/A converter module one by one with the tabular value of low frequency envelope parameters table with certain hour at interval.Can also preset the value of writing frequency in this sending module, in order to determine above-mentioned transmission time interval.
Second kind of execution mode of information modulating unit adopts the hardware modulation system.Communication signal with digital form is converted to the corresponding modulating signal earlier.According to predetermined carrier wave, modulation signal is modulated into high frequency carrier again.This high frequency carrier is low frequency envelope high frequency analog signals.Under the hardware modulation system, the information modulating unit specifically comprises modular converter and modulation module.
Modular converter wherein, the original communication information that is used for receiving is converted to modulation signal, sends to modulation module.Transfer process is more flexible, can adopt hardware circuit to realize, also can adopt software to realize, for example earlier the modulation signal storage of original communication information correspondence is stored with the tabular value form, when conversion, obtain the modulation signal of corresponding digital form according to original communication information, after digital-to-analogue conversion, obtain the modulation signal of analog form.
Modulation module is used for according to modulation signal that receives and the definite carrier wave of this modulation module modulation signal being modulated into carrier wave, forms high frequency carrier.The traditional hardware circuit that adopts this modulation module realizes the signal modulation.
Except the execution mode of above two kinds of information modulating units 102, can also adopt the modulator approach of Direct Digital frequency synthesis (DDS).The modulator approach of this DDS is stored in the low frequency envelope high-frequency digital signal of original communication information correspondence in the hardware store circuit.When ultrasonic communication is carried out in transmission, from this hardware store circuit, obtain low frequency envelope high-frequency digital signal, after digital-to-analogue conversion, drive reflector.
Composition to information reverting unit 112 is elaborated below.Fig. 5 is the composition structural representation of information reverting unit among Fig. 3.Fig. 6 is Fig. 5 information reverting cell signal result schematic diagram.Information reverting unit 112 adopts analog circuit to realize.Referring to Fig. 5 and Fig. 6, information reverting unit 112 specifically comprises amplifying circuit, bandwidth-limited circuit, envelope detection circuit and comparator.
Amplifying circuit is used for the low frequency envelope high frequency analog signals S that receives from receiver 111
AM(t) amplitude is amplified A doubly, the low frequency envelope high frequency analog signals A S that obtains amplifying
AM(t), offer bandwidth-limited circuit.
Bandwidth-limited circuit is used for the A S that will receive from amplifying circuit
AM(t), carry out bandpass filtering, the interference signal under the elimination ultrasonic wave beyond the frequency range obtains low frequency envelope high frequency analog signals AS` after the filtering
AM(t), offer envelope detection circuit.
Envelope detection circuit is used for the A S` that will receive from bandwidth-limited circuit
AM(t) carry out envelope detection, with A S`
AM(t) envelope extraction is come out, and obtains low frequency envelope emulates signal f (t), offers comparator.This envelope detection circuit specifically can adopt existing envelope detector to obtain amplitude earlier and be positive high frequency carrier entirely, adopts low pass filter that amplitude is come out for the envelope extraction of positive high frequency carrier entirely then, obtains f (t).
Comparator is used for f (t) is reduced into the square wave F (t) that is loaded with communication information, and this is a process of judging and regenerating, and is also referred to as shaping.F (t) is communication information.When shaping, adopt comparator as shaping circuit, f (t) is compared with the threshold value 0 of comparator, greater than 0 be designated as 1, otherwise be designated as 0, obtain F (t).
In actual applications, envelope detection circuit can also be with A S`
AM(t) negative envelope extraction is come out, and obtains f1 (t), adopts f1 (t) to compare with 0 value then, minusly is designated as 1, otherwise is designated as 0, then also can obtain the F shown in Fig. 6 (t).Therefore, envelope detection circuit and comparator need be used, and its objective is that the communication information that will carry in the low frequency envelope high-frequency signal restores.Threshold value in the comparator also can not be set to zero.
Fig. 7 is the embodiment of the invention one realizes communication based on ultrasonic wave a method flow diagram.As shown in Figure 7, this method may further comprise the steps:
Step 701: information modulation module 102 receives original communication information, should be modulated to low frequency envelope high frequency analog signals by original communication information, drives reflector 101.
In this step, original communication information is modulated to low frequency envelope high frequency analog signals can adopts above-mentioned software modulator approach, hardware modulator approach or DDS method.Wherein, the software modulator approach is converted to low frequency envelope high-frequency digital signal with original communication information earlier, generates low frequency envelope high frequency analog signals through digital-to-analogue conversion.Adopt the hardware modulator approach, earlier original communication information is converted to modulation signal, adopt traditional hardware circuit that this modulation signal is modulated into high frequency carrier again, i.e. low frequency envelope high frequency analog signals.
Step 702: reflector 101 is converted to the ultrasonic wave that carries original communication information with low frequency envelope high frequency analog signals, and sends to receiving system 110.
Step 703: the receiver 111 of receiving system 110 receives and is loaded with the ultrasonic wave of original communication information, and is converted to low frequency envelope high frequency analog signals and sends to information reverting unit 112.
Step 704: signal processing such as the low frequency envelope high frequency analog signals of the 112 pairs of receptions in information reverting unit is amplified, filtering, detection, shaping restore original communication information.
So far, this flow process finishes.
The binary sequence that original communication information generally is made up of binary numeral, dispensing device 100 is converted to hyperacoustic process of carrying original communication information with original communication information, is the process of one by one binary digit of forming original communication information being handled.
The method flow diagram that Fig. 8 is written into a binary digit ultrasonic wave and sends for the present invention.The modulating part of this method adopts above-mentioned software modulator approach.As shown in Figure 8, this method may further comprise the steps:
Step 800: generate in the control module at waveform, set in advance low frequency envelope parameters table and the value of writing frequency.
In this step, in the waveform generation control module of transmitting terminal, low frequency envelope parameters table and the value of writing frequency are set in advance.Low frequency envelope parameters souvenir has carried the corresponding relation of original communication information and low frequency envelope high-frequency digital signal.Among the present invention, binary one and " 0 " corresponding low frequency envelope high-frequency digital signal of forming original communication information have been stored in the low frequency envelope parameters table.
Before determining the value of writing frequency, at first to determine the signal frequency of low frequency envelope high-frequency digital signal.Suppose that the frequency of high voice that people's ear generally can be heard is 15KHZ, then can to select frequency be the class supersonic band of 15KHZ~20KHZ to low frequency envelope high-frequency digital signal, and perhaps frequency is that the supersonic band of 20KHZ~100KHZ gets final product.The present invention determines that the signal frequency of low frequency envelope high-frequency digital signal is 20KHZ.
The value of writing frequency is that waveform generates the frequency that control module writes D/A converter module with the tabular value in the low frequency envelope parameters table one by one and is converted to low frequency envelope high-frequency digital signal.Because the high-frequency digital signal of low frequency envelope is the high frequency waveforms of alternatively up and down, one-period is made up of two crest numerical value of height.Therefore the value of writing frequency is 2 times of low frequency envelope high-frequency digital signal frequency, and promptly among the present invention, the value of writing frequency is 40KHZ.
The tabular value of low frequency envelope parameters table storage is that the computing formula according to low frequency envelope high-frequency digital signal obtains, and computing formula is as follows:
S
AM(t)=[A
0+f(t)]cosω
ct, (1)
Wherein, A
0Be the DC component of stack, f (t) is the function of low frequency envelope, is modulation signal; Cos ω
cT is a carrier signal.So ω
cBe the angular frequency of carrier wave, its value is 2 π Wc.Wc is 20KHZ, is hyperacoustic required frequency.Certainly Wc can also be the arbitrary value of 20KHZ to tens MHZ.T is that waveform generates control module to the time interval of the D/A converter module value of writing, i.e. the integral multiple of the value of writing frequency inverse.Because the value of writing frequency configuration is 2 times Wc, is 40KHZ here.Therefore the computing formula of the high-frequency digital signal of the low frequency envelope among the present invention is deformed into:
S
AM(t)=[A
0+f(t)]cosnπ,n=0,1,2... (2)
Can know cos ω by inference from above formula
cThe value of t for alternately-1 and 1.When f (t) is the hexagon envelope function, S
AM(t) just formed the high-frequency digital signal of hexagon envelope.
This step 800 was carried out before carrying out ultrasonic communication and is once got final product.
Step 801: read in the original communication information binary digit to be sent.
In this step, these binary messages possibility representative voices, image or instruction etc.
Step 802: judge whether the binary digit that reads is " 0 ".If execution in step 803 then, otherwise execution in step 804.
Step 803: write D/A converter module according to the tabular value in the value of the writing frequency that the is provided with low frequency envelope parameters table that " 0 " is corresponding.Execution in step 805.
The method of this step also is trace-point method, can realize with software.Trace-point method is to drive D/A converter module with different range values at a certain time interval according to the actual waveform that will send, that is to say that the time interval of determining with the value of writing frequency delivers to the tabular value in the low frequency envelope parameters table in the D/A converter module, D/A converter module transfers out low frequency envelope high frequency analog signals just as described point.
Step 804: write D/A converter module according to the tabular value in the value of the writing frequency that the is provided with low frequency envelope parameters table that " 1 " is corresponding.Execution in step 805.
Step 805: D/A converter module is converted to low frequency envelope high frequency analog signals with the tabular value that receives, and drives reflector 101.
Step 806: reflector 101 sends out audio signal according to the low frequency envelope high frequency analog signals that drives its vibration.This audio signal has high frequency characteristics and low frequency envelope, is the ultrasonic wave that is loaded with original communication information.
So far, this flow process finishes.
Below the bit in the original communication information is written into ultrasonic wave with regard to having finished, and the flow process that sends.As long as carrying out this flow process, circulation just can realize producing and sending the ultrasonic wave that is loaded with original communication information.
In actual applications, dispensing device 100 can be encoded to original communication information, sends out the ultrasonic wave that is loaded with the original communication information of coding then.To original communication information coding is losing for fear of information material.Coding method can be adopted single-stage nonreturn to zero code, twin-stage nonreturn to zero code, single-stage NRZ, coded systems such as twin-stage NRZ, differential code.Owing to after the communication information of dispensing device coding sends to receiving system, also will be decoded by receiving system, so dispensing device and receiving system appoint that code encoding/decoding mode gets final product.
Adopt ultrasonic transmission to be loaded with the audio system and the method for code communication information for embodiment two explanations below.
In this case, the embodiment of the invention two realizes the audio system composition structure of communication and the audio system composition structural similarity shown in Fig. 3 based on ultrasonic wave.Difference is, information modulating unit 102 has increased the function that original communication information is encoded, the original communication information of coding behind the coding is modulated to coding back low frequency envelope high frequency analog signals, drives reflector, send the ultrasonic wave that is loaded with the original communication information of coding;
Accordingly, the ultrasonic wave that is loaded with the original communication information of coding that the receiver 111 of receiving system 110 will receive is converted to coding back low frequency envelope high frequency analog signals, sends to information reverting unit 112; The information reverting unit 112 of this moment has only restored the original communication information of coding, and the original communication information that needs to encode is decoded.Therefore, receiving system 110 further comprises control unit.The information reverting unit 112 original communication information of will encoding sends to control unit, by control unit this original communication information of encoding is decoded, and obtains original communication information; This control unit can also carry out subsequent operation according to the original communication information that obtains.Control unit can adopt microprocessor to realize.
When information reverting unit 112 adopted analog circuit to realize, then the original communication information of its coding that restores was the low-frequency square-wave form, so decoded after needing control unit that the original communication information of the coding that carries in the low-frequency square-wave is converted to digital quantity again.Give an example, the original communication information of the coding that carries in the low-frequency square-wave is converted to the method that digital quantity specifically can adopt the constant duration sampling, sampled value is that high level then obtains binary digit " 1 ", and sampled value is that low level then obtains binary digit " 0 ".
Describe having the composition structure that has increased encoding function information modulating unit 102 in the present embodiment below.When adopting the software modulation system to realize, information modulating unit 102 can have two kinds of implementations.Below this dual mode is described respectively.
Mode one: the composition structure that adopts the first kind of implementation of information modulating unit shown in Fig. 4.Then the information modulating unit of the embodiment of the invention two comprises that waveform generates control module and D/A converter module.Wherein, waveform generation control module specifically comprises memory module, generation module and sending module.
Wherein, memory module is stored low frequency envelope high-frequency digital signal after the original communication information corresponding codes.This method is comparatively more simple, but its coded system is changeless.
When storage, suppose that original communication information is made up of " 1 " and " 0 ", " 1 " corresponding codes is " 10 ", " 0 " corresponding codes is " 01 ", then need at first to obtain the high frequency waveforms of " 10 " and " 01 ", low frequency envelope high-frequency digital signal after promptly encoding, low frequency envelope high-frequency digital signal behind the coding of " 01 " of the high-frequency digital signal of low frequency envelope and " 0 " and correspondence thereof behind the coding of " 10 " of storage " 1 " at last and correspondence thereof.
When actual storage, this memory module can be stored the low frequency envelope parameters table of original communication information correspondence, this low frequency envelope parameters souvenir has carried low frequency envelope high-frequency digital signal and the corresponding relation of the two behind original communication information, the coding, and the digital quantity of forming coding back low frequency envelope high-frequency digital signal is the tabular value of low frequency envelope parameters table.
Generation module receives original communication information, obtains the high-frequency digital signal of low frequency envelope after this original communication information corresponding codes from memory module, sends to transmitting element.When obtain from memory module be the low frequency envelope parameters table of original communication information correspondence the time, then this low frequency envelope parameters table is sent to sending module.
Sending module, low frequency envelope high-frequency digital signal behind the coding that the reception generation module sends, and send to D/A converter module.When be received from generation module be low frequency envelope parameters table the time, this sending module sends to D/A converter module one by one with the tabular value of low frequency envelope parameters table with certain hour at interval.Can also preset the value of writing frequency in this sending module, in order to determine above-mentioned transmission time interval.
D/A converter module, sending module send to coding back low frequency envelope high-frequency digital signal, after digital-to-analogue conversion, generate low frequency envelope high frequency analog signals, drive reflector 101.
Mode two: adopt the another kind of the embodiment of the invention two information modulating units shown in Fig. 9 to form structure.As shown in Figure 9, this information modulating unit comprises that waveform generates control module and D/A converter module.Wherein waveform generation control module specifically comprises coding module, memory module, generation module and sending module.
Wherein, coding module is used for the original communication information that generation module is sent is encoded, and returns the original communication information of coding to generation module.
Memory module, low frequency envelope high-frequency digital signal after the original communication information corresponding codes of memory encoding.
After supposing coding that coding module carries out original communication information, the original communication information of encoding is made up of " 1 " and " 0 " of binary digit.One section then respectively that binary digit " 0 " is corresponding in advance high frequency waveforms, the back low frequency envelope high-frequency digital signal of promptly encoding, and low frequency envelope high-frequency digital signal stores behind one section coding of binary digit " 1 " correspondence.Low frequency envelope high-frequency digital signal adopts the set of number scale to show behind each section coding.
When actual storage, the low frequency envelope parameters table that this memory module also can the original communication information correspondence of memory encoding, this low frequency envelope parameters souvenir have carried low frequency envelope high-frequency digital signal and the corresponding relation of the two behind encode original communication information, the coding.The digital quantity of forming coding back low frequency envelope high-frequency digital signal is the tabular value of low frequency envelope parameters table.
Generation module receives original communication information, and sends to coding module and encode, then the original communication information of coding that returns of received code module; From memory module, obtain low frequency envelope high-frequency digital signal after this original communication information corresponding codes of encoding again, send to transmitting element.When obtain from memory module be the coding original communication information correspondence low frequency envelope parameters table the time, then this low frequency envelope parameters table is sent to sending module.
Sending module, low frequency envelope high-frequency digital signal behind the coding that the reception generation module sends, and send to D/A converter module.When be received from generation module be low frequency envelope parameters table the time, this sending module sends to D/A converter module one by one with the tabular value of low frequency envelope parameters table with certain hour at interval.Can also preset the value of writing frequency in this sending module, in order to determine above-mentioned transmission time interval.
D/A converter module, sending module send to coding back low frequency envelope high-frequency digital signal, after digital-to-analogue conversion, generate low frequency envelope high frequency analog signals, drive reflector 101.
Information modulating unit when adopting the hardware modulation system to realize is below formed structure and is described.In order to generate coding back low frequency envelope high frequency analog signals, present embodiment adopts the composition structure of second kind of execution mode of information modulating unit among the embodiment one, be with the difference of embodiment one, in the present embodiment, this information modulating unit further comprises the information coding module, and then the information modulating unit under the present embodiment hardware modulation system comprises modular converter, modulation module and information coding module.
Wherein, modular converter receives original communication information, sends to the information coding module; The original communication information of coding that reception information coding module returns, the original communication information of will encoding is converted to modulation signal, sends to modulation module.
Modulation module is used for according to the modulation signal that receives and definite carrier wave modulation signal being modulated into carrier wave, forms high frequency carrier, sends to reflector 101.
The information coding module receives the original communication information that modular converter sends, and after encoding, returns the original communication information of coding to modular converter.
Figure 10 is the embodiment of the invention two realizes communication based on ultrasonic wave a method flow diagram.The modulating part of this method adopts above-mentioned software modulator approach.As shown in figure 10, this method may further comprise the steps:
Step 1001: waveform generates control module and receives original communication information, to original communication information coding, generates the original communication information of coding; The original communication information of should encoding is converted to coding back low frequency envelope high-frequency digital signal, and sends to D/A converter module.
In this step, original communication information is encoded, and low frequency envelope high-frequency digital signal can have dual mode after being converted to coding:
Mode one, according to original communication information, obtain in advance low frequency envelope high-frequency digital signal after this original communication information corresponding codes of storage, just finished coding and changed.
Mode two, earlier original communication information is encoded, obtain low frequency envelope high-frequency digital signal after this original communication information corresponding codes of encoding of storage in advance then, just finished coding and conversion.
This step with forming the coding digital quantity of low frequency envelope high-frequency digital signal afterwards, sends to D/A converter module according to certain hour when low frequency envelope high-frequency digital signal sends to D/A converter module after waveform generates the coding that control module will obtain at interval.
Step 1002: low frequency envelope high-frequency digital signal is converted to coding back low frequency envelope high frequency analog signals behind the coding that D/A converter module will receive, and drives reflector 101.
Step 1003: low frequency envelope high frequency analog signals was converted to the ultrasonic wave that carries the original communication information of coding after reflector 101 will be encoded, and sent to receiving system 110.
Step 1004: the receiver 111 of receiving system 110 receives the ultrasonic wave that is loaded with the original communication information of coding, and low frequency envelope high frequency analog signals sends to information reverting unit 112 after being converted to coding.
Step 1005: behind the coding of the 112 pairs of receptions in information reverting unit the high frequency analog signals of low frequency envelope amplify, signal processing such as filtering, detection, shaping, go back the original communication information of original encoding, offer control unit.
Step 1006: control unit is decoded to the original communication information of coding of reduction, obtains original communication information.Thereby finished the process of ultrasonic communication.
In this step, control unit adopts step 1001 decoding process corresponding with coded system, and the original communication information of encoding is decoded, and has just obtained original communication information.
So far, this flow process finishes.
Lift several preferred embodiments below and realize that based on ultrasonic wave the method and system of communication describes above-mentioned.Each preferred embodiment all adopts the software modulation system to realize the generation of low frequency envelope high-frequency digital signal.
First preferred embodiment
In this preferred embodiment, the original communication information that send is " 10110 ", and the frequency of low frequency envelope is 100HZ, and ultrasonic frequency is 20KHZ, and the value of writing frequency is 40KHZ.Original communication information adopts the single-stage NRZ as coded system.Table 1 is the original communication information of single-stage NRZ and the mapping table of coded message.As shown in table 1, the binary system " 10 " of the corresponding coded message of the binary one of original communication information; " 00 " of the corresponding coded message of the binary zero of original communication information.
Raw information (DATA) |
Coded message |
DATA |
1 |
10 |
DATA 0 |
00 |
Table 1
Figure 11 is loaded with the ultrasonic wave waveform schematic diagram of the original communication information of coding for the present invention's first preferred embodiment.
As shown in figure 11, each envelope comprises that the hexagon high frequency waveforms of 7.5ms and the horizontal part of the 2.5ms that closelys follow thereafter assign to represent coded message " 10 ", promptly original communication information DATA 1, and the horizontal component of 10ms is represented DATA 0.Therefore when low frequency envelope parameters table is set, can in this parameter list, write down low frequency envelope high-frequency digital signal after the original communication information corresponding codes.That is, the horizontal component of the hexagon high frequency waveforms of 7.5ms and the 2.5ms that closelys follow thereafter is recorded as the low frequency envelope high-frequency digital signal of DATA1 correspondence, the horizontal component of 10ms is recorded as low frequency envelope high-frequency digital signal after the DATA0 corresponding codes.In order to save memory space, can not write down the tabular value of DATA0 correspondence, but judge that current communication information is at 0 o'clock, in 10ms, adopt the transmission frequency of 40KHZ constantly to write D/A converter module with 0.
Figure 12 realizes the audio system composition structural representation of communication based on ultrasonic wave for the present invention's first preferred embodiment.Referring to Figure 12, this system comprises two integrated circuit (IC, Integrate Circuit) GPF8 that insult logical (Generalplus) scientific ﹠ technical corporation, is respectively GPF8-A and GPF8-B; Also envelope loud speaker A, microphone B and analog circuit B.GPF8 is a multichannel voice controller, and this IC has 16 micro-control units (MCU, Micro-Control Unit), flash memory (Flash), D/A circuit and microphone (MIC, Microphone) amplifying circuit etc.
In this system, GPF8-A and loud speaker A have formed hyperacoustic dispensing device; GPF8-B, microphone B and analog circuit B have formed the ultrasonic reception device.
Wherein, by generation module and sending module in the realization of the MCU-A among the GPF8-A dispensing device; D/A circuit A among the GPF8-A realizes the D/A converter module in the dispensing device; Flash memory A among the GPF8-A has realized the function of memory module in the dispensing device.The external loud speaker A of the D/A circuit A of this GPF8-A is as the reflector of dispensing device.Because the D/A circuit among the GPF8 has the sample frequency up to 200KHZ, so GPF8-A can be converted to the high-frequency signal with 100HZ low frequency envelope, about 20KHZ that produces ultrasonic wave by loud speaker A and send fully.
In actual applications, if the tabular value of low frequency envelope parameters table is few, then can adopt read-only memory (ROM, Read Only Memory) among the MCU-A to realize the function of memory module in the dispensing device.
Carry the MIC amplifying circuit among the GPF8-B, the external microphone B of this MIC amplifying circuit, receive the ultrasonic wave that is loaded with original communication information that loud speaker A sends together with microphone B, and be converted to analog signal, send to the analog circuit B that is external in MIC amplifying circuit B.MIC amplifying circuit B among the GPF8-B is used for reducing being received from the common noise of the analog signal of microphone B.
Analog circuit B is made up of amplifying circuit, bandwidth-limited circuit, envelope detection circuit and comparator, realizes the information reverting unit in the receiving system, composition structure promptly illustrated in fig. 5.This analog circuit B to the analog signal that is received from MIC amplifying circuit B amplify, bandpass filtering, envelope detection and shaping handle, and obtains low-frequency square-wave signal F (t), sends to the MCU-B of GPF8-B.
MCU-B among the GPF8-B realizes the control unit in the receiving system.If F (t) carrying is the original communication information of coding, then MCU-B decodes to F (t), obtains original communication information.
Figure 13 is the flow chart of the present invention's first preferred embodiment ultrasonic communication method.As shown in figure 13, this method may further comprise the steps:
Step 1301: the value of writing frequency is set in MCU-A, low frequency envelope parameters table is set in flash memory A.
In the present embodiment, it is 40K HZ that the value of writing frequency at first is set, that is to say GPF8-A with time interval of 25us according to the tabular value of the low frequency envelope parameters table that will send out to the D/A circuit A value of writing;
Then, determine the tabular value of low frequency envelope parameters table, will determine number, coded system and the tabular value of tabular value in the low frequency envelope parameters table when determining.
A) number of tabular value in the low frequency envelope parameters table=value of writing frequency/low frequency envelope frequency, the value of writing frequency is 40K HZ in the present embodiment, and the low frequency envelope frequency is 100HZ, then, the cycle of being converted into is 10000us, that is to say to be 10000us so that finish the time that sends a Data1 or Data0.Therefore, need 40KHZ/100HZ=400 tabular value in the low frequency envelope parameters table altogether, add preceding and the most last 0 tabular value of returning, in fact, the number of numerical value is exactly 402 in each parameter list.
B) present embodiment adopts the single-stage NRZ, and the corresponding relation of its original communication information and coded message is as shown in table 1.
C) tabular value in the low frequency envelope parameters table is set, what store in the low frequency envelope parameters table of Data1 correspondence is the high frequency waveforms of hexagon envelope of 7.5ms and the horizontal component of the 2.5ms that closelys follow thereof, can write a series of values clocklike, totally 402, actual tabular value is as follows:
.dw(0) 0
.dw(1) 327
.dw(2) 654
......
(difference is 327)
......
.dw(p) 32046
.dw(p+1) 32373
......
(amounting to 103 32373)
......
..dw(p+103) 32373
......
(difference is-327)
......
.dw(p+q-1) 654
.dw(p+q) 327
.dw(p+q+1) 0
......
(100 0)
......
.dw(p+q+100)0
Wherein .dw (n) is a n tabular value, n=0,1,2...401; P+q+100=401.When these tabular values are stored in the low frequency envelope parameters table, can adopt the decimal system or binary storage.
The computational methods of calculating above-mentioned tabular value are, making the cosn π perseverance in the formula (2) is 1, and then the formula after the distortion is as follows:
S
AM(t)=A
0+f(t), (3)
Wherein, t=25n (us).In the present embodiment, n=0,1,2...401.
Step 1302:MCU-A receives original communication information, obtains the low frequency envelope parameters table of forming original communication information binary digit correspondence one by one from flash memory A; And, adopt the tabular value of low frequency envelope parameters table to drive D/A circuit A with time interval of 25us.The tabular value of a plurality of binary digit correspondences links together, and has just formed low frequency envelope high-frequency digital signal after the original communication information corresponding codes.
In this step, when reading DATA0, the interruption that MCU-A is provided with 40KHZ sends to D/A with 400 0.
When reading DATA1, MCU-A can be provided with the interruption of 40KHZ and go to get above-mentioned tabular value in order, will get negatively when running into even number time to former tabular value, by initial value, flows to D/A circuit A during odd number time.Will arrive the high frequency analog signals of the low frequency envelope of 20KHZ alternatively up and down like this at the output of D/A circuit A.
In actual applications, also can be according to the tabular value of the computational methods low frequency envelope parameters table of formula (2) storage, then when n was even number .dw (n) was a positive number; When n was odd number .dw (n) was a negative.Then in this step, when reading DATA1, MCU-A is provided with the tabular value that the interruption of 40KHZ removes to get in order low frequency envelope parameters table, flows to D/A circuit A and gets final product.Because tabular value has been the positive and negative numerical value that replaces, therefore the output from D/A circuit A just can obtain low frequency envelope high frequency analog signals.
Step 1303: the low frequency envelope high frequency analog signals that adopts D/A circuit A to generate drives loud speaker A, the ultrasonic wave that is loaded with original communication information is sent to the microphone B of receiving system.
Step 1304: microphone B receives the ultrasonic wave that is loaded with original communication information, is converted to low frequency envelope high frequency analog signals, sends to analog circuit B via MIC amplifying circuit B filtering.
Step 1305: analog circuit B to the low frequency envelope high frequency analog signals that receives amplify, bandpass filtering, envelope detection and shaping handle, and finally obtains low-frequency square-wave signal F (t), sends to MCU-B.
In the present embodiment, the low-frequency square-wave that obtains after step 1305 is carried out as shown in figure 14.
Step 1306:MCU-B decodes to the low-frequency square-wave signal that obtains, and obtains original communication information.
In the present embodiment, coding method as shown in table 1, when then decoding, the corresponding DATA1 of " 10 " signal of low-frequency square-wave signal, the corresponding DATA0 of 00 signal then is " 10110 " according to the original communication information that this principle decodes.
Since then, finished ultrasonic communication one time, this flow process finishes.
The ultrasonic communication scheme of this preferred embodiment has good stable, and the maximum magnitude of sensing can reach 1.5 meters, and directivity is good, but sensing angle is greatly in the 45 degree scopes of microphone dead ahead.
Second preferred embodiment
In first preferred embodiment, what dispensing device sent is ultrasonic wave.In the present embodiment, dispensing device both can send general sound, also can send ultrasonic wave.When sending general sound and ultrasonic wave, can adopt the method for transmission simultaneously or alternate transmission.
Figure 15 realizes the audio system composition structural representation of communication based on ultrasonic wave for the present invention's second preferred embodiment.
As shown in figure 15, this system comprises dispensing device 1500 and receiving system 1510.Dispensing device 1500 comprises information modulating unit 1502 and reflector 1503; Receiving system 1510 comprises microphone 1511, information reverting unit 1512, general sound processing unit 1513 and control unit 1514.
Wherein, information modulating unit 1502 receives original communication information, with its coding and be converted to coding back low frequency envelope high frequency analog signals, sends to reflector 1501.
Reflector 1501 receives low frequency envelope high frequency analog signals behind the coding that information modulating unit 1502 sends, and can also receive the analog signal of general sound, is audio signal with these analog signal conversion, sends to receiving system 1510.The analog signal of general sound can be obtained outside dispensing device 1500, also can the module that be specifically designed to the general acoustic information of storage for example be set directly from other module acquisition of dispensing device 1500.Wherein, general sound can be the irrelevant sound of communicating by letter with ultrasonic waves, also can be and the ultrasonic waves relevant voice command of communicating by letter.
Microphone 1511, the hyperacoustic audio signal that is used to receive the audio signal that comprises general sound of reflector 1501 transmissions and/or is loaded with the original communication information of coding, and be converted to analog signal.Send to information reverting unit 1512 and general sound processing unit 1513.
Information reverting unit 1512, be used for to the analog signal that is received from microphone 1511 amplify, bandpass filtering, extract low frequency envelope high frequency analog signals, it is carried out signal processing such as envelope detection and shaping, obtain the original communication information of coding, send to control unit 1514.Since the analog signal that receives has been carried out bandpass filtering, therefore just can be before envelope detection with low-frequency general voice signal filtering.
General sound processing unit 1513 receives the analog signal that microphone 1511 sends, and it is handled, and extracts low frequency partly.Can comprise a low pass filter in this general sound processing unit 1513, the analog signal that receives is carried out low-pass filtering, extract low frequency partly, general sound processing unit can further partly be handled this low frequency.For instance, general acoustic processing module can be provided with a voice identification module (not shown) in addition, comes the phonetic order in the identification audio frequency sound.Perhaps, general acoustic processing module also can be provided with an information coding/compression module and a logging modle in addition, the analog signal of general sound can be recorded in the logging modle after the encoding compression of information coding/compression module.
Control unit 1514 is used for the original communication information of coding that receives self information reduction unit 1512 is decoded, and obtains original communication information.Can also carry out subsequent treatment by original communication information.
In actual applications, also voice identification module, information coding/compression module and the logging modle of general sound processing unit 1513 can be arranged in the control unit 1514,1513 of then general sound processing units are responsible for the analog signal of general sound is extracted from the audio signal that receives, send to control unit 1514 then, the analog signal of general sound is carried out operations such as encoding compression, record by control unit 1514.
As seen, the present invention can successfully be integrated in existing audio devices with ultrasonic communication, when realizing high frequency sound wave and general sound or alternately transmit.Because the frequency range of high frequency sound wave is higher than the frequency range of general sound sound wave, so in the time of the communication function that the audio system of present embodiment can realize with high frequency sound wave, transmit general sound, and the function of can the interference tones system not original general sound of transmission.
The 3rd preferred embodiment
Above embodiment is ultrasonic wave and/or the general voice signal that single-phase transmission is loaded with original communication information.Present embodiment is that example is described with the transmitted in both directions.In the present embodiment, a dispensing device also can be a receiving system simultaneously, and a dispensing device can send ultrasonic wave to more than one receiving system.
In the embodiment one of Fig. 3 of the present invention, be that dispensing device 100 sends the high frequency carrier that is loaded with original communication information to receiving system 110.In order to increase the interaction function between stream oriented device, the present invention also can make each device all possess and send and the function that receives.For this situation, realize the composition structural representation of the audio system of communication based on ultrasonic wave referring to the 3rd preferred embodiment of the present invention shown in Figure 16.This audio system can include two or more audio devices; Figure 16 shows the audio system that comprises two audio devices, with convenient explanation.This audio system comprises audio devices C and audio devices D, and the composition structure of this audio devices C and audio devices D is identical.
With the example that consists of of audio devices C, be introduced below.
Audio devices C comprises reflector C, information modulating unit C, control unit C, information reverting unit C and receiver C.Wherein, reflector C and information modulating unit C produce and send the ultrasonic wave necessary component that is loaded with original communication information.
Wherein, information modulating unit C receives original communication information C, and it is modulated to low frequency envelope high frequency analog signals, drives reflector C, sends out the ultrasonic wave that is loaded with original communication information C.In the present embodiment, information modulating unit C adopts the structure shown in Fig. 4, adopts the software modulation system to generate low frequency envelope high frequency analog signals.
Receiver C and information reverting unit C receive to be loaded with the ultrasonic wave of original communication information, and restore the necessary component of original communication information.Wherein, receiver C receives the ultrasonic wave that is loaded with original communication information D that audio devices D sends, and is converted into low frequency envelope high frequency analog signals, sends to information reverting unit C, restores original communication letter by information reverting unit C, sends to control unit C.If what receiver C received is the ultrasonic wave that is loaded with the original communication information D of coding, then the C original communication information D of coding that will restore in information reverting unit sends to control unit C.
Comprise control unit C among the audio devices C, this control unit C not only can realize the function of control unit in the aforementioned receiving system, the also running of control audio device C, and tunable audio devices C is in the mutual communication of other audio devices.When audio devices C sent ultrasonic wave, this control unit C can produce or receive original communication information C outside installing.Send to information modulating unit C.When audio devices C receives ultrasonic wave, this control unit C can receive the original communication information or the original communication information of encoding of information reverting unit C reduction, after the original communication information of encoding decoded, obtain original communication information, according to original communication information, control audio device C carries out subsequent operation then.
In addition, the modulator approach of information modulating unit C can be identical or different with the modulator approach of information modulating unit D, and the coding method of information modulating unit C also can be identical or different with the coding method of information modulating unit D.
Figure 17 is the composition structural representation of the present invention's the 3rd preferred embodiment based on an example of both-way communication audio system of ultrasonic wave realization.
As shown in figure 17, this both-way communication system comprises audio devices C and audio devices D.The structure of two audio devices is identical.Audio devices C both can be that transmitting terminal also can be a receiving terminal.Audio devices D both can be that receiving terminal also can be a transmitting terminal.
Audio devices C comprises GPF8-C, microphone C, loud speaker C and external circuits C.
Wherein, realize the control unit C shown in Figure 16, and the waveform among the information modulating unit C generates control module by the MCU-C among the GPF8-C; D/A circuit C among the GPF8-C realizes the D/A converter module among the information modulating unit C; Loud speaker C among the GPF8-C realizes reflector C; Microphone C realizes receiver C, and this microphone C is connected on outward among the GPF8-C on the MIC amplifying circuit C, and C receives the ultrasonic wave that is loaded with original communication information C with the MIC amplifying circuit, and is converted to analog signal, sends to the analog circuit C that is external in MIC amplifying circuit C; The original communication information that analog circuit C will reduce or the original communication information of encoding send to the MCU-C among the GPF8-C, realize the function of information reverting unit C.This analog circuit C is made up of amplifying circuit, bandwidth-limited circuit, envelope detection circuit and comparator, can adopt composition structure illustrated in fig. 5.
As seen, the audio devices C that GPF8-C and external circuits thereof are formed has possessed reception and has sent the hyperacoustic function that is loaded with communication information.
Audio devices D comprises GPF8-D, microphone D, loud speaker D and external circuits D.Identical with corresponding part function among the audio devices C with annexation.
As seen, the audio devices D that GPF8-D and external circuits thereof are formed has also possessed reception and transmission and has been loaded with the hyperacoustic function of communication information.
Therefore, adopt audio devices C and audio devices D, send and receive mode can realize dual-machine communication according to the ultrasonic wave of above embodiment.When audio devices C is set is transmitting terminal, sends when being loaded with the ultrasonic wave of original communication information, and audio devices D is a receiving terminal; Vice versa.
Audio devices C can send the ultrasonic wave that is loaded with original communication information to a plurality of audio devices; In like manner, also can receive the ultrasonic wave that is loaded with original communication information that a plurality of audio devices are sent.Thereby realized the ultrasonic communication between the multimachine.
On this system-based, foundation is stablized good communication mechanism and just can be realized the correct two-shipper or the both-way communication of multimachine.When setting up communication mechanism, fixing communication data structure at first will be set, make the ultrasonic wave receiving terminal can resolve the concrete meaning of the original communication information of transmitting terminal transmission, also needing to distinguish is that transmitting terminal sends, and sets up also unusual necessity of correctness that necessary authentication mechanism guarantees transmission information in addition.Based on above requirement to the communication data structure, 16 bits (Bit) the communication data structure shown in the present embodiment employing table 2.
Data bit (Bit) |
FEDCBA98 |
7654 |
3210 |
The meaning of communication data |
The communication information particular content |
Receiving terminal ID |
Transmitting terminal ID |
Table 2
As shown in table 2, in order to determine the receiving terminal and the transmitting terminal of communication data, transmitting terminal ID is arranged on the Bit3~Bit0 of communication information, receiving terminal ID is arranged on the Bit7~Bit4 of original communication information.Transmitting terminal ID and receiving terminal ID are 4 binary digit, for example 0001,0010 etc.The most-significant byte of original communication information is represented the particular content of communication information.Original communication information receiving terminal judges according to receiving terminal ID whether this machine is the correct receiving terminal of communication information.
Figure 18 is the method flow diagram of the two-way ultrasonic communication of the present invention's the 3rd preferred embodiment.As shown in figure 18, this method may further comprise the steps:
Step 1801: transmitting terminal sends original communication information to receiving terminal.
In this step, the original communication information that transmitting terminal sends comprises transmitting terminal ID, receiving terminal ID and original communication information particular content.
Step 1802: receiving terminal returns the original communication information that receives and gives transmitting terminal.
In this step, after receiving terminal receives original communication information, at first judge according to the receiving terminal ID in the original communication information whether this machine is the receiving terminal of this original communication information; If not, then can abandon this original communication information; If just this original communication information is carried out subsequent treatment.
When receiving terminal returns the original communication information of its reception to transmitting terminal, the transmitting terminal ID and the receiving terminal ID of original communication information changed, return to transmitting terminal again.
Step 1803: whether transmitting terminal is the original communication information that self sends by the original communication information of confirming receiving terminal and returning, judge receiving terminal whether correct received original communication information; If then execution in step 1804; Otherwise execution in step 1805.
In this step 1803, transmitting terminal receives original communication information also to be needed to confirm earlier whether this original communication information sends to oneself, if, confirm the original communication information particular content in this original communication information again, whether with identical from the original communication information particular content that sends in the original communication information in step 1801, and if identical would judge receiving terminal correct received original communication information.
In the following steps, an end that receives original communication information all needs to judge whether self is the receiving terminal of this communication information earlier, just explanation no longer one by one.
Step 1804: transmitting terminal sends to receiving terminal confirms correct information 0x0000, and its binary form is 0,000 0,000 0,000 0000.Execution in step 1806 then.
Step 1805: transmitting terminal sends to receiving terminal confirms error message 0xFFFF, and its binary form is 1,111 1,111 1,111 1111.Execution in step 1806 then.
Step 1806: receiving terminal judges whether to receive the confirmation correct information 0x0000; If then execution in step 1807; Otherwise execution in step 1810 and 1811.
Step 1807: receiving terminal returns to transmitting terminal confirms correct information 0x0000, and changes accepting state over to, begins to wait for.
Step 1808: judge whether to wait for that 400ms does not receive data; If then execution in step 1809; Otherwise return execution in step 1802.
Step 1809: the original communication information that receiving terminal receives step 1802 is as this communication information.This communication finishes.
Step 1810: receiving terminal returns the affirmation information of reception to transmitting terminal, enters accepting state again.
In this step, this confirmation may be 0xFFFF, also may be other data message.
Step 1811: transmitting terminal is confirmed this Communications failure, resends communication data.Return execution in step 1802.
For the ease of judging the arrival of communication information, this preferred embodiment increased a start bit before communication information.The communication information that receiving terminal receives as shown in figure 19.Referring to Figure 19, this communication information is the low-frequency square-wave signal that is loaded with original communication information that receiving terminal obtains through signal processing.Start bit is arranged before the communication information, immediately following communication information, only shows low 5 of 16Bit communication information data among Figure 19 after the start bit, its high 11 not shown.When receiving terminal had detected the rising edge arrival, whether high level had kept 5ms to the waveform of detection start bit.Certainly, in actual applications, because the time that the drift high level of analog circuit keeps can be very inaccurate.Therefore when the high level of judging start bit keeps 4~9ms, just can confirm that start bit is stable; Judge that current what receive is the original communication information that ultrasonic wave carried that transmitting terminal sends.At this moment, the MCU opens interrupters of receiving terminal with the frequency of 100KHZ, reads 16 secondary data, be read as low level then this data bit for " 0 ", if high level then this data bit be " 1 "; Read finish after, 16 bit data that read out are the original communication information that this transmitting terminal sends.
In this preferred embodiment,, all be to finish by the MCU in the GPF8 chip to the judgement that receives the communication information correctness to the detection of communication information start bit.Sending hyperacoustic while, transmitting terminal also can send general sound.
Ultrasonic communication scheme of the present invention also can be used for sensing periphery object.Audio devices C shown in Figure 17, it sends hyperacoustic loud speaker C and receives hyperacoustic microphone C is separate, in conjunction with the good reflection characteristic of ultrasonic wave, just can adopt loud speaker C to send ultrasonic wave, adopt the ultrasonic wave of microphone C reception through reflection, and after MIC amplifying circuit C filtering, send to MCU-C, whether receive the object that ultrasonic wave judges whether to sense periphery by the MCU-C basis, can also calculate the distance of the object of periphery that senses according to the ultrasonic wave that receives.
The present invention can be applied to the ultrasonic wave or the hyperacoustic communications field of class.More than each embodiment only ultrasonic communication is described, the hyperacoustic means of communication of class are identical with the method for ultrasonic communication, just ultrasonic wave is different with the class frequency of ultrasonic, therefore when the value of writing frequency is provided with, needs the 2 times of conduct value of writing frequencies of the frequency of employing class supersonic band.
By the above as can be seen, the ultrasonic communication scheme that the embodiment of the invention provided adopts simple method and apparatus to finish ultrasonic communication, and cost is low.But also realized the ultrasonic communication of two-shipper and even multimachine.
In summary, technical scheme of the present invention can utilize general common audio system to realize based on the hyperacoustic communication of ultrasonic wave/class.Compare with existing ultrasonic communication technology, the present invention can reduce the cost of realizing ultrasonic communication, and more convenient universal this ultrasonic communication technology makes masses can enjoy convenience and benefit that this technology is brought.
In fact, in the information-intensive society in modern times, many electronic installations itself have the audio frequency interlock circuit, similarly are audio tweeter/buzzer/microphone and Audio Controller, microprocessor or the like.For example, many electronic installations can be pointed out the state of its running with various musical sounds, voice or buzzer, or the feedback action of controlling as the user; Some electronic toy can be sounded and user's interaction.In addition, acoustic control or voice-operated device are also very common.For example, some light fixture can be started by the sound of clapping one's hands, and the then available voice of some mobile phone, portable computer or electronic toy are controlled.Have in the device of audio frequency interlock circuit in these itself, the present invention just can utilize existing audio frequency interlock circuit further to make these devices can have the function of communication interaction, improve the surcharge of these devices, it is more convenient also to allow the user use.On the other hand, because the cost of audio frequency interlock circuit of the present invention itself is just low, even itself does not have the audio frequency interlock circuit some electronic installation, adopt the technology of the present invention to set up the audio frequency interlock circuit and realize that the cost of communication function is still low than having the technical scheme that realizes ultrasonic communication now, the advantage of sequitur the technology of the present invention.
In sum, more than be preferred embodiment of the present invention only, be not to be used to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.