CN102176778A - Control method of wireless microphone system - Google Patents
Control method of wireless microphone system Download PDFInfo
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- CN102176778A CN102176778A CN2010106001141A CN201010600114A CN102176778A CN 102176778 A CN102176778 A CN 102176778A CN 2010106001141 A CN2010106001141 A CN 2010106001141A CN 201010600114 A CN201010600114 A CN 201010600114A CN 102176778 A CN102176778 A CN 102176778A
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention discloses a control method of a wireless microphone system, and the method is applied to a wireless microphone system which comprises a voice sending device and a voice receiving device. The method comprises: the voice sending device sends channel request frames to the voice receiving device in all channels within the working frequency range; the voice receiving device replies to the channel response frames after receiving the channel request frames; then the voice sending device sends an address binding frame to the voice receiving device; the voice receiving device replies a binding determination frame, thereby realizing the binding of the voice sending device and the voice receiving device; and finally, the voice sending device and the voice receiving device carry out voice signal transmission with each other. According to the invention, the voice sending device can be used for coordinating with one or more voice receiving devices without one-to-one correspondence, therefore, the voice sending device can be possessed and carried about by the individual, is more convenient and much cleaner to use and safer; and the microphone can be maintained conveniently.
Description
Technical field
The present invention relates to a kind of control method of wireless microphone system.
Background technology
At present, people need be applied to wireless microphone in a lot of occasions of productive life, for example, teacher at school the time and the performer when performance, all need to use wireless microphone.Wireless microphone comprises discrete microphone microphone (voice dispensing device) and microphone receiver (pronunciation receiver).Existing microphone microphone all needs and the binding of the microphone receiver fixed, microphone receiver can only with the microphone microphone cooperating of its pairing.Therefore, each teacher before class needs microphone receiver and microphone microphone are borrowed to the classroom, and the microphone microphone is used jointly by numerous teachers, is unfavorable for the healthy of teacher, also is unfavorable for the maintenance of microphone microphone.Teachers wish to have the microphone microphone that the individual has alone very much, the each microphone microphone that only need carry on class separately, the microphone receiver fixed placement is used more convenient, much cleaner in the classroom like this, and more help the maintenance of microphone, prolong the useful life of microphone.
In addition, for example when opening conference, need a plurality of microphone receivers and come voice emplifying.Present case is, needs system of structure that each microphone receiver is all coupled together, and amplifies together then, and such scene has a lot of in disorder long electric wires.
Summary of the invention
The present invention seeks to: at the deficiencies in the prior art, and present demand to individual dedicated voice dispensing device, a kind of control method that comprises the wireless microphone system of voice dispensing device and pronunciation receiver is provided, can be embodied as each user and distribute a voice dispensing device, and do not need demand with the corresponding one by one use of pronunciation receiver, make voice dispensing device can and any one or a plurality of pronunciation receiver cooperating, and voice signal is encrypted, the voice dispensing device can the individual be had alone, carry, use more convenient, much cleaner, safer, and help the maintenance of microphone.
Technical scheme of the present invention is: a kind of control method of wireless microphone system is applied to comprise comprise the steps: the wireless microphone system of voice dispensing device and pronunciation receiver
Step 1: described voice dispensing device on all channels of working frequency range to pronunciation receiver channel request frame;
Step 2: after described pronunciation receiver receives the channel request frame, reply channel and reply frame;
Step 3: described voice dispensing device sends the address binding frame to pronunciation receiver after receiving that channel is replied frame;
Step 4: after pronunciation receiver is received the address binding frame, reply the binding acknowledgement frame, described voice dispensing device and pronunciation receiver realize binding;
Step 5: carry out the voice signal transmission between described voice dispensing device and the pronunciation receiver.
Further, the control method of described wireless microphone system also comprises the steps:
Step 21: the voice dispensing device receives the channel switching command, sends the switching channels claim frame;
Step 22: pronunciation receiver is received the switching channels request, and all channels in the working frequency range are carried out energy measuring, calculates idle channel as optimum channel, sends the optimum channel request to the voice dispensing device, and switches to optimum channel;
Step 23: the voice dispensing device switches to optimum channel after receiving the optimum channel request, and feeds back a channel and reply frame.
Further, the control method of described wireless microphone system also comprise the steps: described voice dispensing device with a plurality of not when the pronunciation receiver of same channel is communicated by letter, the voice dispensing device detects the signal strength signal intensity of the channel answer frame of pronunciation receiver transmission, replys frame to the pronunciation receiver transmitting channel that signal strength signal intensity is the strongest.
Further, in voice dispensing device and pronunciation receiver, be provided with an identical key array, the control method of described wireless microphone system gets in the step 5 and also comprises: in the voice dispensing device, a key in voice signal and the key array carries out XOR and realizes the voice signal encryption, voice signal after transmission is encrypted then, pronunciation receiver is carried out the deciphering of XOR realization voice signal with encrypted speech signal and this key that receives.
Further, the production method of random key is as follows in the control method of described wireless microphone system: generate a binary number at random as seed by the time, get back 8, and correspond in 128 keys of key array one.
Further, the control method of described wireless microphone system comprises the steps: that also the voice dispensing device detects the size of voice signal, during greater than the sound thresholding, voice signal is radioed to pronunciation receiver at voice signal.
Further, the control method of described wireless microphone system comprises the steps: that also the voice dispensing device after receiving mute command, enters resting state, after receiving mute command once more, and the state of resuming work.
Further, in the control method of described wireless microphone system, under binding state, pronunciation receiver does not receive the channel request of other voice dispensing devices, within a certain period of time, if pronunciation receiver is not received any Frame, then enter and take off binding state, can receive the channel request of other voice dispensing devices, realize binding with other voice dispensing devices.
Advantage of the present invention is:
1. after having adopted control method of the present invention, the voice dispensing device can break away from the constraint of fixing a pronunciation receiver, voice dispensing device can and any one or a plurality of pronunciation receiver cooperating, therefore, people can have the voice dispensing device alone, carry, and need only and the wireless binding of pronunciation receiver during use, use more conveniently, much cleaner, and more help the maintenance of microphone.
2. after having adopted control method of the present invention, in the occasion that a plurality of pronunciation receiver of needs amplify, only need a voice dispensing device and each pronunciation receiver to carry out wireless binding one by one, need not between the pronunciation receiver to connect with line, make the scene more succinct, do not have complicated in disorder wiring.
3. adopt control method of the present invention, carried out in the process of voice transfer voice signal is encrypted because key produces as seed at random by the time, at every turn to the key of voice encryption all changing, increased the fail safe of wireless transmission.
4. adopt control method of the present invention, make microphone have voice open function and mute function, can reduce the power consumption of voice dispensing device, more energy-conserving and environment-protective, service time is longer.
Description of drawings
Below in conjunction with drawings and Examples the present invention is further described:
Fig. 1 is the voice collecting amplifier section schematic diagram of voice dispensing device of the present invention;
Fig. 2 is the voice signal analog-to-digital conversion circuit diagram of voice dispensing device of the present invention;
Fig. 3 is the schematic diagram to the sign indicating number binding procedure of wireless microphone system of the present invention;
Fig. 4 is the schematic diagram of the channel switching process of wireless microphone system of the present invention.
Fig. 5 is the groundwork flow chart of voice dispensing device of the present invention;
Fig. 6 is the groundwork flow chart of pronunciation receiver of the present invention.
Embodiment
Embodiment: a wireless microphone system comprises a voice dispensing device and at least one pronunciation receiver, is operated in 2.4GHz (ZigBee frequency range).The voice dispensing device to voice signal gather, preposition amplification and wireless transmission.Pronunciation receiver links to each other with power amplifier by the audio interface of 3.5mm, realizes recovery and amplification to voice signal.Pronunciation receiver is provided with the switch of selecting working channel, can select one arbitrarily in channel 0～channel 15.Adopt wireless microphone system of the present invention, a voice dispensing device is communicated by letter on same channel bands with a plurality of pronunciation receiver.
The control method of wireless microphone system such as Fig. 3-shown in Figure 6, comprise the steps:
Step 1: the voice dispensing device on all channels of working frequency range to pronunciation receiver channel request frame.Frame format such as table 1.
Table 1
In the table 1, panID is a network number; Load is the data that need transmission; MacDestAddr is MAC (Media Access Control) layer destination address, the address of the destination node of this mac frame; MacSrcAddr is a MAC layer source address, sends the node address of this mac frame; Framecontrol is the frame control word; Sequence is a number of frames, and scope is 1～65535, and this sequence number is write by the source address node of load; DestAddr is the load destination address; SrcAddr is the load source address.Wherein the frame control word format is as shown in table 2:
Table 2
| bit15～bit9 | bit?8～bit?5 | bit?4～bit?0 |
| Keep | type | radius |
The type of Type representative frame wherein, the type=2 Frame; The type=3 data are replied frame; Type=4 switching channels claim frame; The type=5 command frame; Type=6 channel request frame; The type=7 channel is replied frame; Type=10 address binding frame; Type=11 binding acknowledgement frame.
For the channel request frame, Load comprises channel number.
For Frame, Load comprises temporal information.
Step 2: after described pronunciation receiver received the channel request frame, feedback channel was replied frame.Channel is replied the identical of the frame format of frame and channel request frame, and just type is 7 in the frame control word.
Step 3: described voice dispensing device is received channel answer frame, at this moment the voice dispensing device has just been determined the channel at pronunciation receiver place, send the address binding frame to pronunciation receiver, the frame format of address binding frame is identical with the channel request frame, and just type is 10 in the frame control word.
Step 4: after pronunciation receiver is received the address binding frame, reply the binding acknowledgement frame, described voice dispensing device and pronunciation receiver realize binding.
Step 5: carry out the voice signal transmission between described voice dispensing device and the pronunciation receiver, the voice dispensing device sends Frame.After pronunciation receiver receives speech data frame, the audio frequency that processing obtains is exported with pulse width modulation (PWM) by the I/O mouth.The waveform of output restores primary signal after through a low pass filter.
Wherein, step 1～step 4 we be referred to as to sign indicating number and the binding step.In use, open the mains switch of the voice dispensing device of wireless microphone system, just can realize automatically to sign indicating number and binding with receiving system.After the binding, pronunciation receiver A receives only the voice signal of voice dispensing device a, and do not receive other voice dispensing devices to sign indicating number and voice signal.Have only after this voice dispensing device a does not send voice signal 2 minutes, be considered as taking off binding state, just receive other voice dispensing devices and receiving system A and carry out sign indicating number and binding.And voice dispensing device a do not send after the voice signal 2 minutes, sends voice signal again, then need not sign indicating number, directly can communicate by letter.The voice dispensing device is provided with the sign indicating number key, when the user presses this button, begins sign indicating number and binding step from step 1 again.
If a plurality of pronunciation receiver that are operated in same channel are arranged, then voice dispensing device and each pronunciation receiver directly all carry out step 1 to step 5 to sign indicating number, binding and communication process.If a plurality of pronunciation receiver are not at same channel, then the voice dispensing device detects the signal strength signal intensity of the channel answer frame of pronunciation receiver transmission, replys frame to the pronunciation receiver transmitting channel that signal strength signal intensity is the strongest, realizes the binding with this pronunciation receiver.
The circuit theory diagrams of voice dispensing device such as Fig. 1～shown in Figure 2.The voice collecting amplifier section is seen Fig. 1, and the voice signal of the microphone microphone being imported by pull-up resistor R3 changes into the signal of telecommunication, and inputs to the voice signal amplifying circuit.The voice signal amplifying circuit comprises the MC33204 operational amplifier, after voice signal is carried out 2 grades of amplifications, give the voice signal analog-to-digital conversion circuit of back, the direct current biasing of input signal is provided by power supply, and the AC signal of input signal is to be obtained after straight-through the friendship through a big electric capacity by the voice collecting end.After 2 grades of amplifications, can make the faint signal of telecommunication amplify more than 90 times.Voice signal analog-to-digital conversion circuit sees that Fig. 2 is finished by the AD module of master chip MC13213 inside.According to the speech sample theorem, will need carry out the sampling of 8KHz to voice signal.This time that just needs to produce a 8KHz interrupts, and the voice signal after amplifying is sampled, quantized, and its quantified precision is 8, has so just produced 8 pulse code modulation (pcm).In order to reduce power consumption, the present invention asks difference average to the value of each AD conversion, when difference mean value during greater than threshold value, just voice signal is handled and sent part and send data.Otherwise this signal thinks that faint environmental noise will not send.The implementation of Here it is language open function.Voice signal is handled to send partly and is mainly finished by master chip MC13213.
When the user finds that the Channel Transmission effect of voice transfer is bad, can switch on other channels, control method of the present invention can be selected an optimum channel automatically, to guarantee the transport communication quality.The switching channels function is only used under a voice dispensing device and a pronunciation receiver binding state.Specifically as shown in Figure 5, comprise the steps: that the user presses the switching channels key on the voice dispensing device, the voice dispensing device receives the channel switching command, sends the switching channels claim frame.Pronunciation receiver is received the switching channels request, all channels in the working frequency range (channel 0～channel 15) are carried out energy measuring, be specially is the CCA value of all channel energy to be carried out 128 samplings ask average, calculate idle channel as optimum channel, and to the request of voice dispensing device transmission optimum channel, and after sending the optimum channel request, switch to optimum channel immediately.The voice dispensing device switches to optimum channel after receiving the optimum channel request, and feeds back a channel and reply frame to pronunciation receiver.
Because the voice dispensing device of this wireless microphone system and pronunciation receiver are not to fix matching usedly one by one, therefore more need to consider the safety issue of wireless transmission in the voice transfer process of step 5.Adopt wireless microphone system of the present invention to have the voice transfer encryption function, specific practice is: a cipher key number group that contains 128 keys is arranged on respectively in voice dispensing device and the pronunciation receiver, in the voice dispensing device, generate a binary number at random as seed by the time, get back 8, and correspond in 128 keys of key array one, for example, if generate binary number 11111111, then correspond to the 128th key in the key array.Then voice signal and this random key that obtains are carried out XOR, the realization voice signal is encrypted, voice signal data frame after transmission is encrypted then, pronunciation receiver receives the Frame that contains the encrypted speech signal, extracting time information, and same operate time generates binary number as seed, and correspond to this random key in the key array, then encrypted speech signal and key are carried out XOR, realize the voice signal deciphering, and the output of the voice signal audio frequency after will deciphering.Voice signal to each wireless transmission is encrypted, its key produces at random during each the transmission, promptly each key to voice encryption changes, even the result of same data after different time is encrypted also is different, even therefore the cracker has known the key array or has produced number at random and can't crack speech data, thereby has increased the fail safe of wireless transmission greatly.
In addition, wireless microphone system can have mute function, when the user does not need to send voice signal, presses the quiet key on the voice dispensing device, and the voice dispensing device enters resting state after receiving mute command, farthest save power consumption.When pressing quiet key once more, after the voice dispensing device is received mute command once more, the state of resuming work.Switching channels key, quiet key and the sign indicating number key is connected on the chip MC13213 by a resistance respectively.
The above only is the preferred embodiments of the present invention, can not limit scope of the invention process with this, and all simple conversion of doing according to claim of the present invention and description all should still belong to the protection range that the present invention covers.
Claims (8)
1. the control method of a wireless microphone system is applied to comprise it is characterized in that the wireless microphone system of voice dispensing device and pronunciation receiver comprising the steps:
Step 1: described voice dispensing device on all channels of working frequency range to pronunciation receiver channel request frame;
Step 2: after described pronunciation receiver receives the channel request frame, reply channel and reply frame;
Step 3: described voice dispensing device sends the address binding frame to pronunciation receiver after receiving that channel is replied frame;
Step 4: after pronunciation receiver is received the address binding frame, reply the binding acknowledgement frame, described voice dispensing device and pronunciation receiver realize binding;
Step 5: carry out the voice signal transmission between described voice dispensing device and the pronunciation receiver.
2. according to the control method of a kind of wireless microphone system described in the claim 1, it is characterized in that also comprising the steps:
Step 21: the voice dispensing device receives the channel switching command, sends the switching channels claim frame;
Step 22: pronunciation receiver is received the switching channels request, and all channels in the working frequency range are carried out energy measuring, calculates idle channel as optimum channel, sends the optimum channel request to the voice dispensing device, and switches to optimum channel;
Step 23: the voice dispensing device switches to optimum channel after receiving the optimum channel request, and feeds back a channel and reply frame.
3. according to the control method of a kind of wireless microphone system described in the claim 1, it is characterized in that comprising the steps: described voice dispensing device with a plurality of not when the pronunciation receiver of same channel is communicated by letter, the voice dispensing device detects the signal strength signal intensity of the channel answer frame of pronunciation receiver transmission, replys frame to the pronunciation receiver transmitting channel that signal strength signal intensity is the strongest.
4. according to the control method of a kind of wireless microphone system described in the claim 1, it is characterized in that: in voice dispensing device and pronunciation receiver, be provided with an identical key array, also comprise in the step 5: in the voice dispensing device, a key in voice signal and the key array carries out XOR and realizes the voice signal encryption, voice signal after transmission is encrypted then, pronunciation receiver is carried out the deciphering of XOR realization voice signal with encrypted speech signal and this key that receives.
5. according to the control method of a kind of wireless microphone system described in the claim 4, the production method that it is characterized in that described random key is as follows: generate a binary number at random as seed by the time, get back 8, and correspond in 128 keys of key array one.
6. according to the control method of a kind of wireless microphone system described in the claim 1, it is characterized in that also comprising the steps: that the voice dispensing device detects the size of voice signal, during greater than the sound thresholding, voice signal is radioed to pronunciation receiver at voice signal.
7. according to the control method of a kind of wireless microphone system described in the claim 1, it is characterized in that also comprising the steps: that the voice dispensing device after receiving mute command, enters resting state, after receiving mute command once more, the state of resuming work.
8. according to the control method of a kind of wireless microphone system described in the claim 1, it is characterized in that: under binding state, pronunciation receiver does not receive the channel request of other voice dispensing devices, within a certain period of time, if pronunciation receiver is not received any Frame, then enter and take off binding state, can receive the channel request of other voice dispensing devices, realize binding with other voice dispensing devices.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104427448A (en) * | 2013-08-21 | 2015-03-18 | 鸿合科技有限公司 | Wireless microphone connection method and apparatus, and wireless microphone |
| CN110972051A (en) * | 2019-12-20 | 2020-04-07 | 深圳市博音科技有限公司 | One-to-two type bone conduction hearing aid method |
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| CN1417952A (en) * | 2001-10-31 | 2003-05-14 | 松下电器产业株式会社 | Rodio microphone system, phonetic receiver and radio microphone |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110972051A (en) * | 2019-12-20 | 2020-04-07 | 深圳市博音科技有限公司 | One-to-two type bone conduction hearing aid method |
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Application publication date: 20110907 |