CN201063858Y - Wireless surrounding system - Google Patents

Wireless surrounding system Download PDF

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Publication number
CN201063858Y
CN201063858Y CNU2007201486525U CN200720148652U CN201063858Y CN 201063858 Y CN201063858 Y CN 201063858Y CN U2007201486525 U CNU2007201486525 U CN U2007201486525U CN 200720148652 U CN200720148652 U CN 200720148652U CN 201063858 Y CN201063858 Y CN 201063858Y
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China
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signal
coupled
output
wireless
surrounding system
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CNU2007201486525U
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Chinese (zh)
Inventor
刘扬伟
张国威
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Princeton Technology Corp
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Princeton Technology Corp
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Abstract

The utility provides a wireless encircling system, comprising a sound generating device, a sound playing device, and a speaker. The sound generating device outputs sound signals in wireless way, the sound playing device receives the signals to produce analog signals, and the speaker plays the analog signals. Noises of the substrate are not coupled in the circuit of the utility wireless encircling system, so the noise performance of the circuit is improved.

Description

Wireless surrounding system
Technical field
The utility model relates to a kind of surrounding system, particularly relevant for a kind of wireless voice surrounding system.
Background technology
Family's theater notion constantly promotes in recent years, and many families ask for more ultimate attainment audio-visual enjoyment, with audio-visual equipment in family overall reorganization again, adds traditional rear-projection TV and retires backstage gradually, and the plasm TV and the LCD TV that replace are propagated its belief on a large scale.Therefore, family's theater also becomes the leading trend of next ripple of the audio-visual upgrading in parlor thereupon around audio.
Modern consumer is except the quality that requires audio and play, and for meeting furnishings and space requirement in the family, mini, the volume that do not take up space, and the demand of good arrangement all are the conditions of choosing that family's theater group is favored.
Yet, general family is when planning space designs, seldom can prearrange the circuit of family's theater or loudspeaker, and, need six sound channels (left surround channel, right surround channel, preposition L channel, preposition R channel, center channels and supper bass sound channel) at least if desire realizes desirable family's theater.Each sound channel all needs a connecting line, can receive the voice signal that main frame (enlarger) is exported, and therefore, the collocation of numerous and diverse wire rod for most people, have the complete family's theater of a cover and be not easy really.
The utility model content
The utility model provides a kind of wireless surrounding system to comprise, a flexible piezoelectric sound-generating devices and a sound play device.Flexible piezoelectric sound-generating devices comprises, a sound generating unit, a digital signal processor and one first transceiver.The sound generating unit is in order to provide a voice signal.The digital signal processor processes voice signal is to produce a clock pulse signal.First transceiver is launched one first wireless signal according to clock signal, and comprises a transmitter module.Transmitter module is in order to launching first wireless signal, and has a modulation circuit.The modulating circuit modulates clock signal producing one first modulation signal and second modulation signal, and is handled first modulation signal and second modulation signal, to produce first wireless signal.Sound play device comprises, a receiver module, a decoding/transducer and a loud speaker.Receiver module is in order to receiving one second wireless signal, and comprises a single-ended input both-end output amplifier circuit, a treatment circuit and a demodulator circuit.Single-ended input both-end output amplifier circuit is in order to amplifying second wireless signal, and it is right to produce a differential wave.The processing circuit processes differential wave is right, to produce one first processing signals and second processing signals.Demodulator circuit demodulation first processing signals and second processing signals are to produce a restituted signal.Decoding/transducer is in order to the decoding restituted signal, and converts the restituted signal after decoded to an analog signal.Loud speaker is in order to play analog signal.
Wireless surrounding system described in the utility model, this modulation circuit wherein comprises: a frequency divider (Frequency Divider), carry out frequency division to produce sampled signal to this clock signal; One buffer (Buffer) is coupled to this frequency divider, is used for storing the data of input; One integrator is coupled to this buffer, is used for carrying out integration according to the data of this buffer output; One second read-only memory is coupled to this integrator, is used for changing the data that this integrator is exported according to a cosine function; And one the 3rd read-only memory, be coupled to this integrator, be used for changing the data of this integrator output according to a SIN function.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises one first read-only memory (Read Only Memory, ROM), this first read-only memory is coupled to this frequency divider, this buffer and this integrator, this first read-only memory carries out data after an over-sampling (Over-sampling) action in order to store this frequency divider with the data of this buffer, and gives this integrator according to the data that a Gaussian function is changed behind this over-sampling.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises one first digital/analog converter, is coupled to this second read-only memory, is used for the data transaction of this second read-only memory output is become analog signal.
Wireless surrounding system described in the utility model, wherein, this modulation circuit more comprises one first low pass filter, is coupled to this first digital/analog converter, is used for filtering analog signal after this first digital/analog converter conversion to produce this first modulation signal.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises one first frequency mixer, is coupled to this first low pass filter, is used for this first modulation signal and first carrier signal that this first low pass filter produces are carried out mixing.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises one second digital/analog converter, is coupled to the 3rd read-only memory, is used for the data transaction of the 3rd read-only memory output is become analog signal.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises one second low pass filter, be coupled to this second digital/analog converter, be used for filtering analog signal after this second digital/analog converter conversion to produce this second modulation signal.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises one second frequency mixer, is coupled to this second low pass filter, is used for this second modulation signal and second carrier signal that this second low pass filter produces are carried out mixing.
Wireless surrounding system described in the utility model, wherein this modulation circuit more comprises a subtracter, is coupled to this first frequency mixer and this second frequency mixer, is used for producing signal poor of the signal of this first frequency mixer output and the output of this second frequency mixer.
Wireless surrounding system described in the utility model wherein more comprises a power amplifier, and poor in order to the signal of the signal that amplifies the output of this first frequency mixer and the output of this second frequency mixer is to produce this first wireless signal.
Wireless surrounding system described in the utility model, wherein this integrator is to be an accumulator (Accumulator).
Wireless surrounding system described in the utility model, wherein this buffer, this first read-only memory, this integrator, this second read-only memory and the 3rd read-only memory are to utilize digital circuit to finish.
Wireless surrounding system described in the utility model wherein more comprises an adjuster, is coupled between this first read-only memory and this integrator, is used for adjusting the data of this first read-only memory output.
Wireless surrounding system described in the utility model wherein more comprises a selector, is used for selecting the data with this buffer output to input to this first read-only memory processing or be directly inputted into this integrator without this first read-only memory processing.
Wireless surrounding system described in the utility model, wherein this selector is to be coupled to this buffer.
Wireless surrounding system described in the utility model, wherein more comprise a test circuit, this test circuit is to be coupled between this frequency divider and this buffer, and the sampled signal of utilizing this frequency divider to produce produces one group of Pseudo-Random Noise Code (Pseudo RandomNoise).
Wireless surrounding system described in the utility model wherein more comprises an XOR gate, and this XOR gate comprises a first input end, is coupled to an output of this test circuit, is used for receiving this group Pseudo-Random Noise Code, and second input is to be used for receiving an input signal.
Wireless surrounding system described in the utility model wherein should be organized Pseudo-Random Noise Code and this input signal through after this XOR gate, and this XOR gate transmits one and outputs signal to this buffer.
Wireless surrounding system described in the utility model, this single-ended input both-end output amplifier circuit wherein comprises: an amplifier in order to this second wireless signal is enlarged into an amplifying signal, and comprises an input and one first output; An and single-ended input both-end output conversion circuit, it is right in order to this amplifying signal is converted to this differential wave, comprise: a first transistor, be used for receiving this amplifying signal, has a first grid that is coupled to this first output, be coupled to one the one the first utmost point of one second output, and one the one the second utmost point that is coupled to a first node; One transistor seconds has a second grid, is coupled to one the two the first utmost point of one the 3rd output, and one the two the second utmost point that is coupled to this first node; One second electric capacity is coupled between this second output and the second grid; One first resistance is coupled between this second output and the voltage source; One second resistance is coupled between the 3rd output and this voltage source; And a current source, be coupled between this first node and the earth point.
Wireless surrounding system described in the utility model wherein more comprises an antenna, is used for receiving this second wireless signal, or launches this first wireless signal.
Wireless surrounding system described in the utility model, wherein this antenna is to be single-ended antenna.
Wireless surrounding system described in the utility model, wherein this second wireless signal is a radiofrequency signal.
Wireless surrounding system described in the utility model, wherein this single-ended input both-end output amplifier circuit more comprises one first electric capacity, is coupled between this first output and this single-ended input both-end output conversion circuit.
Wireless surrounding system described in the utility model, wherein this amplifier is to be the single-ended output amplifier of single-ended input.
Wireless surrounding system described in the utility model, wherein this amplifier is to be low noise amplifier.
Wireless surrounding system described in the utility model, wherein this amplifier is to be the string stacked type amplifier.
Wireless surrounding system described in the utility model, wherein this amplifier comprises: one first inductance is coupled to this input; One the 5th electric capacity is coupled between this first inductance and the Section Point; One second inductance is coupled between this voltage source and this first output; One the 3rd transistor has one the 3rd grid that is coupled to this Section Point, is coupled to one the three the first utmost point of this first output, and one the three the second utmost point; And one the 3rd inductance, be coupled between the three the second utmost points and this earth point.
Wireless surrounding system described in the utility model, wherein this amplifier more comprises one the 4th transistor, is coupled between this first output and the 3rd transistorized the three the first utmost points, and has one the 4th grid, is coupled to this voltage source.
Wireless surrounding system described in the utility model, wherein this amplifier more comprises a bias generator, is biased into this Section Point in order to apply one.
Wireless surrounding system described in the utility model, wherein this amplifier more comprises one the 3rd resistance, is coupled between this bias generator and the Section Point.
Wireless surrounding system described in the utility model, wherein this second output and the 3rd output are the signals of output low noise coefficient and high-gain.
Wireless surrounding system described in the utility model, wherein this second output and the 3rd output are to be coupled to one first signal input part and the secondary signal input that an image signal is eliminated frequency mixer respectively.
Wireless surrounding system described in the utility model wherein more comprises: one the 3rd electric capacity is coupled between this second output and this first signal input part; And one the 4th electric capacity, be coupled between the 3rd output and this secondary signal input.
Wireless surrounding system described in the utility model, this demodulator circuit wherein, comprise: one first demodulation module, in order to this first processing signals is carried out demodulation, to produce one first restituted signal, this first demodulation module comprises: one first band pass filter, carry out phase deviation to this first processing signals; One first automatic corrective loop is coupled to this first band pass filter, is used for proofreading and correct the centre frequency of this first band pass filter to fix the phase deviation of this first band pass filter to this first processing signals of input; One first phase comparator, the relatively phase difference of first processing signals after this first processing signals and the phase deviation, and output result relatively; And one second demodulation module, in order to this second processing signals is carried out demodulation, to produce one second restituted signal, this second demodulation module comprises: one second band pass filter, carry out phase deviation to this second processing signals; One second automatic corrective loop is coupled to this second band pass filter, is used for proofreading and correct the centre frequency of this second band pass filter to fix the phase deviation of this second band pass filter to this second processing signals of input; And one second phase comparator, the relatively phase difference of second processing signals after this second processing signals and the phase deviation, and output result relatively.
Wireless surrounding system described in the utility model, wherein this first band pass filter and this first automatic corrective loop are made of components identical, and this second band pass filter and this second automatic corrective loop are made of components identical.
Wireless surrounding system described in the utility model, wherein this first band pass filter is to be first mutual conductance-electric capacity (Transconductance-C) filter, this second band pass filter is to be second mutual conductance-capacitive filter.
Wireless surrounding system described in the utility model, wherein this first automatic corrective loop comprises: one first oscillator (Oscillator) is used for producing one first with reference to clock signal; One first integrator is coupled to this first oscillator, and this first integrator is to be used for first producing one first output amplitude with reference to clock signal and one first operating voltage according to this; One first amplitude comparator, it has one the 3rd input is to be coupled to this first integrator, and one four-input terminal be to be coupled to this first oscillator, this first amplitude comparator is used for relatively this first output amplitude of this first integrator and this first amplitude with reference to clock signal of this first oscillator, and exports one first comparative result; And one first operating voltage adjuster, it has an input is to be coupled to this first amplitude comparator, and one output be to be coupled to this first integrator, this first band pass filter, this first operating voltage adjuster is to be used for inputing to according to this first comparative result adjustment of this first amplitude comparator output this first operating voltage of this first integrator and this first band pass filter.
Wireless surrounding system described in the utility model, wherein this second automatic corrective loop comprises: one second oscillator (Oscillator) is used for producing one second with reference to clock signal; One second integral device is coupled to this second oscillator, and this second integral device is to be used for second producing one second output amplitude with reference to clock signal and one second operating voltage according to this; One second amplitude comparator, it has one the 5th input is to be coupled to this second integral device, and one the 6th input be to be coupled to this second oscillator, this second amplitude comparator is used for relatively this second output amplitude of this second integral device and this second amplitude with reference to clock signal of this second oscillator, and exports one second comparative result; And one second operating voltage adjuster, it has an input is to be coupled to this second amplitude comparator, and one output be to be coupled to this second integral device, this second band pass filter, this second operating voltage adjuster is to be used for inputing to according to this second comparative result adjustment of this second amplitude comparator output this second operating voltage of this second integral device and this second band pass filter.
Wireless surrounding system described in the utility model, wherein this first integrator has one first single gain frequency, this first output amplitude is that this second integral utensil has one second single gain frequency corresponding to this first single gain frequency, and this second output amplitude is corresponding to this second single gain frequency.
Wireless surrounding system described in the utility model, wherein this of this first integrator first single gain frequency is the centre frequency corresponding to this first band pass filter, and this second single gain frequency of this second integral device is the centre frequency corresponding to this second band pass filter.
Wireless surrounding system described in the utility model, wherein this first integrator comprises: one first trsanscondutor, be coupled to this first oscillator and this first operating voltage adjuster, be used for according to this producing one first drive signal first with reference to clock signal and this first operating voltage; And one first electric capacity, be coupled to this first trsanscondutor, be used for discharging and recharging according to this first drive signal, produce this first output amplitude.
Wireless surrounding system described in the utility model, wherein this second integral device comprises: one second trsanscondutor, be coupled to this second oscillator and this second operating voltage adjuster, be used for according to this producing one second drive signal second with reference to clock signal and this second operating voltage; And one second electric capacity, be coupled to this second trsanscondutor, be used for discharging and recharging according to this second drive signal, produce this second output amplitude.
Wireless surrounding system described in the utility model, this demodulator circuit wherein more comprises: one first analog-to-digital converter, be coupled to this first phase comparator, be used for converting the result of this first phase comparator output to this first restituted signal; And one second analog-to-digital converter, be coupled to this second phase comparator, be used for converting the result of this second phase comparator output to this second restituted signal.
Wireless surrounding system described in the utility model, the noise of substrate can not be coupled into circuit, can improve the noise performance of circuit thus.
Description of drawings
Fig. 1 is the schematic diagram of wireless surrounding system of the present utility model.
Fig. 2 is the inside calcspar of wireless surrounding system of the present utility model.
Fig. 3 is the inside calcspar of transceiver of the present utility model.
Fig. 4 is that one of modulation circuit may embodiment.
Fig. 5 is another possibility embodiment of modulation circuit.
Fig. 6 is that one of single-ended input both-end output amplifier circuit may embodiment.
Fig. 7 a is that one of single-ended input both-end output conversion circuit may embodiment.
Fig. 7 b is that one of amplifier shown in Figure 6 may embodiment.
Fig. 8 is that one of treatment circuit of the present utility model may embodiment.
Fig. 9 a is that one of demodulator circuit of the present utility model may embodiment.
Fig. 9 b is that one of demodulation module may embodiment.
Fig. 9 c is another possibility embodiment of demodulation module.
Figure 10 is that one of automatic corrective loop may embodiment.
Embodiment
For allow of the present utility model should and other purposes, feature and advantage can become apparent, cited below particularlyly go out preferred embodiment, and cooperate appended graphicly, be described in detail below.
Fig. 1 is the schematic diagram of wireless surrounding system of the present utility model.As shown in the figure, wireless surrounding system 100 comprises, a flexible piezoelectric sound-generating devices 110 and a sound play device.Flexible piezoelectric sound-generating devices 110 is (for example infrared ray or bluetooth) wirelessly, and voice signal is sent to sound play device.Sound play device comprises, supper bass sound channel 121, center channels 122, preposition L channel 123, preposition R channel 124, left surround channel 125 and right surround channel 126.
Because supper bass sound channel 121, center channels 122, preposition L channel 123, preposition R channel 124, left surround channel 125 and right surround channel 126 all similar, difference only is the sound frequency difference that it is play, below the event is example with supper bass sound channel 121 only, and the relation between flexible piezoelectric sound-generating devices 110 and the supper bass sound channel 121 is described.
Fig. 2 is the inside calcspar of wireless surrounding system of the present utility model.As shown in the figure, flexible piezoelectric sound-generating devices 110 comprises, a sound generating unit 111, a digital signal processor (Digital Signal Processor; DSP) 112 and transceiver 113.Sound generating unit 111 is in order to provide a voice signal S AU Digital signal processor 112 processing audio signal S AU, to produce a clock pulse signal CLK.Transceiver 113 is launched wireless signal S according to clock signal CLK W1
Supper bass sound channel 121 comprises, a transceiver 210, a decoding/transducer 220 and a loud speaker 230.Transceiver 210 receives wireless signal S W2, to produce a restituted signal S DMIn the present embodiment, wireless signal S W2Be wireless signal S W1Decoding/transducer 220 decoding restituted signal S DM, and with the restituted signal S after decoded DMConvert an analog signal S to AN Loud speaker 230 is in order to play analog signal S AN
Fig. 3 is the inside calcspar of transceiver of the present utility model.As shown in the figure, transceiver 30 has transmitter module 31 and receiver module 32.Transmitter module 31 is in order to emission wireless signal S W3, and receiver module 32 is in order to receive wireless signal S W4
In the present embodiment, when transceiver 30 is applied to 110 li of flexible piezoelectric sound-generating devices, then have only the transmitter module 31 can action, and receiver module 32 can not move, therefore, the transceiver 113 that flexible piezoelectric sound-generating devices is 110 li only has the function of emission.In addition, wireless signal S shown in Figure 3 W3Be wireless signal S shown in Figure 2 W1
When transceiver 30 is applied to 121 li of supper bass sound channels, have only the receiver module 32 can action, and transmitter module 31 can not move, therefore, transceiver 210 only has the function of reception.In addition, wireless signal S shown in Figure 3 W4Be wireless signal S shown in Figure 2 W2
As shown in Figure 3, transmitter module 31 has a modulation circuit 310, in order to modulation clock signal CLK, producing one first modulation signal and second modulation signal, and handles this first modulation signal and second modulation signal, to produce wireless signal S W3
Receiver module 32 has a single-ended input both-end output amplifier circuit 321, treatment circuit 322 and demodulator circuit 323.Single-ended input both-end output amplifier circuit 321 is in order to amplify wireless signal S W4, and produce a differential wave to S DI1, S DI2Treatment circuit 322 is handled differential wave to S DI1, S DI2, to produce processing signals S P1, S P2Demodulator circuit 323 demodulation process signal S P1, S P2, to produce a restituted signal S DM
Fig. 4 is that one of modulation circuit may embodiment.As shown in the figure, modulation circuit 310 comprises, a frequency divider (Frequency Divider) 311, one buffer (Buffer) 312, read-only memory 313~314, an integrator 316 and an adjuster 317.
311 couples of clock signal CLK of frequency divider carry out frequency division to produce sampled signal CLKN.Suppose that clock signal CLK has a frequency f,, then have one frequency f/n through the sampled signal CLKN behind the frequency divider 311 if frequency divider 311 will reach n sample rate doubly.
The temporary a series of input signal DATAIN of buffer 312, and store according to sampled signal CLKN sample obtained data and export read-only memory 313 to of input signal DATAIN.
Read-only memory 313 is according to the signal of input 431,432 inputs, the data that storage frequency divider 311 is exported buffer 312 are carried out the data after the over-sampling action, then the data transaction after this over-sampling action is become the corresponding data of Gaussian function, and utilize the mode of tabling look-up to read.
Adjuster 317 is coupled between read-only memory 313 and the integrator 316, is used for adjusting the data of read-only memory 313 outputs.Integrator 316 carries out integration according to the data that adjuster 317 is exported.Wherein, integrator 316 is to be an accumulator (Accumulator), is used for reaching the purpose of integration.
Read-only memory 314 couples the output of integrator 316, becomes the corresponding data of cosine function in order to the data transaction with integrator 316 outputs, and utilizes the mode of tabling look-up, and exports an output signal DATAOUT1.
Read-only memory 315 couples integrator 316, becomes the corresponding data of SIN function in order to the data transaction with integrator 316 outputs, and utilizes the mode of tabling look-up, and exports an output signal DATAOUT2.
In other embodiments, read-only memory 313 and adjuster 317 can omit.When read-only memory 313 and adjuster 317 were omitted, then the signal exported of 316 pairs of buffers 312 of integrator carried out integration.In addition, buffer 312, read-only memory 313~315 and integrator 316 are to utilize digital circuit to finish.
Fig. 5 is another possibility embodiment of modulation circuit.Fig. 5 is similar in appearance to Fig. 4, difference is, the modulation circuit more than 50 of Fig. 5 digital/analog converter 511,521, low pass filter 512,522, frequency mixer 513,523, subtracter 531, power amplifier 541, selector 551, test circuit 561 and XOR gate 581.
Digital/analog converter 511 couples read-only memory 314, becomes analog signal in order to the data transaction with read-only memory 314 outputs.Low pass filter 512 couples digital/analog converter 511, and the analog signal after changing in order to filtration digital/analog converter 511 is to produce first modulation signal.Frequency mixer 513 couples low pass filter 512, carries out mixing in order to first modulation signal and the carrier signal C1 that low pass filter 512 is produced.
Digital/analog converter 521 couples read-only memory 315, becomes analog signal in order to the data transaction that read-only memory 315 is exported.Low pass filter 522 couples digital/analog converter 521, and the analog signal after changing in order to filtration digital/analog converter 521 is to produce second modulation signal.Frequency mixer 523 couples low pass filter 522, carries out mixing in order to second modulation signal and the carrier signal C2 that low pass filter 522 is produced.
Subtracter 531 couples frequency mixer 513 and 523, is used for producing signal poor of the signal of frequency mixer 513 outputs and frequency mixer 523 outputs.Power amplifier 541 is poor in order to the signal of the signal of amplifiermixer 513 output and frequency mixer 523 outputs, to produce wireless signal S W3
Selector 551 couples buffer 312, is used for selecting the data with buffer 312 outputs to input to read-only memory 313 processing or be directly inputted into this integrator 316 without read-only memory 313 processing.
Test circuit 561 couples between frequency divider 311 and the buffer 312, and the sampled signal CLKN that utilizes frequency divider 311 to produce produces one group of Pseudo-Random Noise Code (Pseudo Random Noise).This group Pseudo-Random Noise Code that acceptance test circuit 561 is produced and input signal DATAIN are through after the XOR gate 581, and XOR gate 581 transmits one and outputs signal to buffer 312.
Fig. 6 is that one of single-ended input both-end output amplifier circuit may embodiment.As shown in the figure, single-ended input both-end output amplifier circuit 321 comprises, an amplifier 610, single-ended input both-end output conversion circuit 620 and electric capacity 630.
Amplifier 610 is in order to wireless signal S W4Be enlarged into an amplifying signal.Amplifier 610 can be the single-ended output amplifier of single-ended input, low noise amplifier or string stacked type amplifier.Single-ended input both-end output conversion circuit 620 is in order to be converted to differential wave to S with this amplifying signal DI1, S DI2Wherein differential wave is to S DI1, S DI2Signal for low noise coefficient and high-gain.
Electric capacity 630 is in order to the filtering direct current signal, and only makes AC signal be sent to single-ended input both-end output conversion circuit 620.
In the present embodiment, single-ended input both-end output amplifier circuit 321 more comprises an antenna 640, in order to receive wireless signal S W4Antenna 640 can be single-ended antenna, and wireless signal S W4Can be radiofrequency signal.And in other embodiment, electric capacity 630 is to be omitted.
Fig. 7 a is that one of single-ended input both-end output conversion circuit may embodiment.As shown in the figure, single-ended input both-end output conversion circuit 620 comprises, transistor 701,702, resistance 703,704, current source 705 and electric capacity 706.
The grid of transistor 701 is coupled to electric capacity 630, as single-ended input to both-end transducer 620, in order to receive the amplifying signal by single-ended output amplifier 610 outputs of single-ended input.The drain electrode of transistor 701 is to be coupled to output 709, and its source electrode is to be coupled to Node B.The grid of transistor 702 is to be coupled to electric capacity 706, and its drain electrode is to be coupled to output 709 ', and its source electrode is to be coupled to Node B.
Electric capacity 706 is to be coupled between the grid of output 709 and transistor 702, is coupled to the grid of transistor 702 in order to the voltage level with the drain electrode of transistor 701.When the amplifying signal of single-ended output amplifier 610 outputs of single-ended input is high level, transistor 701 conductings, make the voltage level of drain electrode of transistor 701 descend, and see through the grid that electric capacity 706 is coupled to transistor 702, make transistor 701 and 702 grid receive and have the input signal that phasic difference mutually 180 is spent.Therefore, make single-ended output output have the both-end output signal that phase place differs 180 degree to both-end transducer 620.
In addition, resistance 703 is to be coupled between voltage source V DD and the output 709, and resistance 704 is to be coupled between voltage source V DD and the output 709 ', and current source 705 is to be coupled between Node B and the earth point VSS.
In the present embodiment, single-ended input both-end output amplifier 321 more comprises electric capacity 707,708 and image signal elimination frequency mixer 650.Electric capacity 707 is to be coupled between output 709 and the image signal elimination frequency mixer 650, and electric capacity 708 is to be coupled between output 709 ' and the image signal elimination frequency mixer 650.Thus, the both-end output signal of single-ended input both-end output amplifier circuit 321 can be sent to image signal and eliminate frequency mixer 650, to carry out down conversion process.
Single-ended is to be used for the amplifying signal after amplifying through the single-ended output amplifier 610 of single-ended input is converted to the both-end output signal that phase phasic difference 180 is spent to both-end transducer 620.Single-ended differential in the both-end transducer 620 to the shunt capacitance over the ground of negative input end in the conventional art is removed, and electric capacity 706 is coupled to the drain electrode of positive input terminal (transistor 701) from the grid of negative input end (transistor 702), because electric capacity 706 directly is not connected to earth point VSS, therefore the noise of substrate can not be coupled into circuit, can improve the noise performance of circuit thus.
Fig. 7 b is that one of amplifier shown in Figure 6 may embodiment.In this embodiment, amplifier 610 is to be example with string stacked type low noise amplifier (Cascode Low NoiseAmplifier), and it is made of transistor 711,712, inductance 713~715, electric capacity 716, resistance 717, bias generator Bias, voltage source V DD and earth point VSS.
The grid of transistor 711 is to be coupled to voltage source V DD, and its drain electrode is to be coupled to output 718, and its source electrode is the drain electrode that is coupled to transistor 712.The grid of transistor 712 is to be coupled to node A.Inductance 713 is to be coupled between input 719 and the electric capacity 716, and wherein, input 719 is single-ended input signals that reception antenna 640 is received.Electric capacity 716 is to be coupled between inductance 713 and the node A.Resistance 717 is to be coupled between node A and the bias generator Bias.Inductance 714 is to be coupled between voltage source V DD and the output 718.Inductance 715 is to be coupled between the source electrode and earth point VSS of transistor 712.
Fig. 8 is that one of treatment circuit of the present utility model may embodiment.As shown in the figure, treatment circuit 322 comprises, frequency mixer 811,812 and low pass filter 820.Frequency mixer 811 in order to differential wave to S DI1Carry out mixing with carrier signal C1.Frequency mixer 812 in order to differential wave to S DI2Carry out mixing with carrier signal C2.Low pass filter 820 is in order to filter through the signal after frequency mixer 811 and 812 mixing to produce processing signals S P1And S P2
Fig. 9 a is that one of demodulator circuit of the present utility model may embodiment.As shown in the figure, demodulator circuit 323 comprises, demodulation module 910 and 920 and conversion equipment 930. Demodulation module 910 and 920 is respectively to processing signals S P1And S P2Carry out demodulation, to produce restituted signal S DM1And S DM2Conversion equipment 930 is again with restituted signal S DM1And S DM2Convert restituted signal S to DMBecause demodulation module 910 and 920 constitutive requirements are all identical, thus below be example only with demodulation module 910.
Fig. 9 b is that one of demodulation module may embodiment.As shown in the figure, demodulation module 910 comprises, band pass filter 911, automatic corrective loop 912 and phase comparator 913.
911 couples of processing signals S of band pass filter P1Carry out phase deviation, to produce a shifted signal S PS1Automatically corrective loop 912 couples band pass filter 911, is used for proofreading and correct the processing signals S of the centre frequency of band pass filter 911 with 911 pairs of inputs of fixed band bandpass filter P1Phase deviation.Phase comparator 913 comparison process signal S P1With the processing signals S after the phase deviation PS1Phase difference, and output result relatively.
Fig. 9 c is another possibility embodiment of demodulation module.Fig. 9 c is similar in appearance to Fig. 9 b, and difference is that Fig. 9 c has an analog/digital converter 914, converts numerical data in order to the result with phase comparator 913 outputs.
Band pass filter 911, automatic corrective loop 912 can be located on the same chip with phase comparator 913.And band pass filter 911 is made of components identical with automatic corrective loop 912.For example band pass filter 911 is one trsanscondutor-capacitive filters, and then automatically corrective loop 912 can comprise an integrator that is made of trsanscondutor, electric capacity.
Figure 10 is that one of automatic corrective loop may embodiment.As shown in the figure, corrective loop 912 comprises an oscillator (Oscillator) 1010, an integrator 1020, an amplitude comparator 1030 and an operating voltage adjuster 1040 automatically.
Oscillator 1010 is used for producing one with reference to clock signal CLKR.Integrator 1020 produces an output amplitude according to a reference clock signal CLKR and an operating voltage V1.The amplitude of the reference clock signal CLKR that output amplitude that amplitude comparator 1030 comparison integrators 1020 are produced and oscillator 1010 are produced, and export a comparative result.The comparative result that operating voltage adjuster 1040 is exported according to amplitude comparator 1030 is adjusted the operating voltage V1 that inputs to integrator 1020 and band pass filter 911.
Integrator 1020 has a single gain frequency fu, and single gain frequency fu is determined by trsanscondutor gm and capacitor C, single gain frequency fu=transconductance value/(2*pi* capacitance).Therefore, single gain frequency fu of integrator 1020 is identical (duplicate identical trsanscondutor and electric capacity, wherein trsanscondutor gm is all identical with the transconductance value of band pass filter 911) with the centre frequency fc of band pass filter 911.As long as adjust integrator 1020 and band pass filter 911 synchronously, single gain frequency fu of integrator 1020 is the centre frequency fc corresponding to band pass filter 911, when single gain frequency fu of integrator 1020 adjusts to right value, the centre frequency fc of band pass filter 911 also can adjust to right value.Integrator 1020 is operated in frequency when being single gain frequency fu, and its gain is 1, and meaning is that input voltage vin is identical with the amplitude of output voltage V out.
As shown in the figure, integrator 1020 comprises a trsanscondutor gm and a capacitor C.Trsanscondutor gm couples oscillator 1010 and operating voltage adjuster 1040, is used for producing a drive signal according to reference clock signal CLKR and operating voltage V1.Capacitor C couples trsanscondutor gm, is used for discharging and recharging according to the drive signal that trsanscondutor gm is produced, to produce this output amplitude.
The above only is the utility model preferred embodiment; so it is not in order to limit scope of the present utility model; any personnel that are familiar with this technology; in not breaking away from spirit and scope of the present utility model; can do further improvement and variation on this basis, so the scope that claims were defined that protection range of the present utility model is worked as with the application is as the criterion.
Being simply described as follows of symbol in the accompanying drawing:
100: wireless surrounding system
110: flexible piezoelectric sound-generating devices
121: the supper bass sound channel
122: center channels
123: preposition L channel
124: preposition R channel
125: left surround channel
126: right surround channel
111: the sound generating unit
220: decoding/converter
113,210,30: transceiver
230: loudspeaker
112: digital signal processor
31: transmitter module
32: receiver module
310,50: modulation circuit
321: single-ended input both-end output amplifier circuit
322: treatment circuit
323: demodulator circuit
311: frequency divider
312: buffer
313~314: read-only memory
316,1020: integrator
317: adjuster
531: subtracter
511,521: digital/analog converter
541: power amplifier
512,522,820: low pass filter
551: selector
513,523,811,812: frequency mixer
561: test circuit
581: XOR gate
610: amplifier
620: single-ended input both-end output conversion circuit
630,706,707,708,716, C: electric capacity
640: antenna
705: current source
650: image signal is eliminated frequency mixer
713~715: inductance
701,702,711,712: transistor
719: input
703,704,717: resistance
910,920: demodulation module
709,709 ', 718: output
911: band pass filter
912: automatic corrective loop
913: phase comparator
914: analog/digital converter
930: conversion equipment
1010: oscillator
1030: amplitude comparator
Gm: trsanscondutor
1040: the operating voltage adjuster

Claims (44)

1. a wireless surrounding system is characterized in that, this wireless surrounding system comprises:
One flexible piezoelectric sound-generating devices comprises:
One sound generating unit is in order to provide a voice signal;
One digital signal processor is handled this voice signal, to produce a clock pulse signal; And
One first transceiver according to this clock signal, is launched one first wireless signal, and this first transceiver comprises:
One transmitter module in order to launch one first wireless signal, comprising:
One modulation circuit is modulated this clock signal, producing one first modulation signal and second modulation signal, and handles this first modulation signal and second modulation signal, to produce this first wireless signal; And
One sound play device comprises:
One receiver module in order to receive one second wireless signal, comprising:
One single-ended input both-end output amplifier circuit, in order to amplifying this second wireless signal, and it is right to produce a differential wave;
One treatment circuit, it is right to handle this differential wave, to produce one first processing signals and second processing signals; And
One demodulator circuit, this first processing signals of demodulation and second processing signals are to produce a restituted signal;
One decoding/transducer in order to deciphering this restituted signal, and converts this restituted signal after decoded to an analog signal; And
One loud speaker is in order to play this analog signal.
2. wireless surrounding system according to claim 1 is characterized in that, this modulation circuit comprises:
One frequency divider carries out frequency division to produce sampled signal to this clock signal;
One buffer is coupled to this frequency divider, is used for storing the data of input;
One integrator is coupled to this buffer, is used for carrying out integration according to the data of this buffer output;
One second read-only memory is coupled to this integrator, is used for changing the data that this integrator is exported according to a cosine function; And
One the 3rd read-only memory is coupled to this integrator, is used for changing the data that this integrator is exported according to a SIN function.
3. wireless surrounding system according to claim 2, it is characterized in that, this modulation circuit more comprises one first read-only memory, this first read-only memory is coupled to this frequency divider, this buffer and this integrator, this first read-only memory carries out data after the over-sampling action in order to store this frequency divider with the data of this buffer, and gives this integrator according to the data that a Gaussian function is changed behind this over-sampling.
4. wireless surrounding system according to claim 2 is characterized in that, this modulation circuit more comprises one first digital/analog converter, is coupled to this second read-only memory, is used for the data transaction of this second read-only memory output is become analog signal.
5. wireless surrounding system according to claim 4, it is characterized in that, this modulation circuit more comprises one first low pass filter, is coupled to this first digital/analog converter, is used for filtering analog signal after this first digital/analog converter conversion to produce this first modulation signal.
6. wireless surrounding system according to claim 5, it is characterized in that, this modulation circuit more comprises one first frequency mixer, is coupled to this first low pass filter, is used for this first modulation signal and first carrier signal that this first low pass filter produces are carried out mixing.
7. wireless surrounding system according to claim 6 is characterized in that, this modulation circuit more comprises one second digital/analog converter, is coupled to the 3rd read-only memory, is used for the data transaction of the 3rd read-only memory output is become analog signal.
8. wireless surrounding system according to claim 7, it is characterized in that, this modulation circuit more comprises one second low pass filter, is coupled to this second digital/analog converter, is used for filtering analog signal after this second digital/analog converter conversion to produce this second modulation signal.
9. wireless surrounding system according to claim 8, it is characterized in that, this modulation circuit more comprises one second frequency mixer, is coupled to this second low pass filter, is used for this second modulation signal and second carrier signal that this second low pass filter produces are carried out mixing.
10. wireless surrounding system according to claim 9, it is characterized in that, this modulation circuit more comprises a subtracter, is coupled to this first frequency mixer and this second frequency mixer, is used for producing signal poor of the signal of this first frequency mixer output and the output of this second frequency mixer.
11. wireless surrounding system according to claim 10 is characterized in that, more comprises a power amplifier, poor in order to the signal of the signal that amplifies the output of this first frequency mixer and the output of this second frequency mixer is to produce this first wireless signal.
12. wireless surrounding system according to claim 2 is characterized in that, this integrator is to be an accumulator.
13. wireless surrounding system according to claim 3 is characterized in that, this buffer, this first read-only memory, this integrator, this second read-only memory and the 3rd read-only memory are to utilize digital circuit to finish.
14. wireless surrounding system according to claim 3 is characterized in that, more comprises an adjuster, is coupled between this first read-only memory and this integrator, is used for adjusting the data of this first read-only memory output.
15. wireless surrounding system according to claim 3, it is characterized in that, more comprise a selector, be used for selecting data to input to this first read-only memory processing or be directly inputted into this integrator without this first read-only memory processing with this buffer output.
16. wireless surrounding system according to claim 15 is characterized in that, this selector is to be coupled to this buffer.
17. wireless surrounding system according to claim 2 is characterized in that, more comprises a test circuit, this test circuit is to be coupled between this frequency divider and this buffer, and the sampled signal of utilizing this frequency divider to produce produces one group of Pseudo-Random Noise Code.
18. wireless surrounding system according to claim 17 is characterized in that, more comprises an XOR gate, this XOR gate comprises a first input end, be coupled to an output of this test circuit, be used for receiving this group Pseudo-Random Noise Code, second input is to be used for receiving an input signal.
19. wireless surrounding system according to claim 18 is characterized in that, this group Pseudo-Random Noise Code and this input signal are through after this XOR gate, and this XOR gate transmits one and outputs signal to this buffer.
20. wireless surrounding system according to claim 1 is characterized in that, this single-ended input both-end output amplifier circuit comprises:
One amplifier in order to this second wireless signal is enlarged into an amplifying signal, and comprises an input and one first output; And
One single-ended input both-end output conversion circuit, right in order to this amplifying signal is converted to this differential wave, comprising:
One the first transistor is used for receiving this amplifying signal, has a first grid that is coupled to this first output, is coupled to one the one the first utmost point of one second output, and one the one the second utmost point that is coupled to a first node;
One transistor seconds has a second grid, is coupled to one the two the first utmost point of one the 3rd output, and one the two the second utmost point that is coupled to this first node;
One second electric capacity is coupled between this second output and the second grid;
One first resistance is coupled between this second output and the voltage source;
One second resistance is coupled between the 3rd output and this voltage source; And
One current source is coupled between this first node and the earth point.
21. wireless surrounding system according to claim 20 is characterized in that, more comprises an antenna, is used for receiving this second wireless signal, or launches this first wireless signal.
22. wireless surrounding system according to claim 21 is characterized in that, this antenna is to be single-ended antenna.
23. wireless surrounding system according to claim 20 is characterized in that, this second wireless signal is a radiofrequency signal.
24. wireless surrounding system according to claim 20 is characterized in that, this single-ended input both-end output amplifier circuit more comprises one first electric capacity, is coupled between this first output and this single-ended input both-end output conversion circuit.
25. wireless surrounding system according to claim 20 is characterized in that, this amplifier is to be the single-ended output amplifier of single-ended input.
26. wireless surrounding system according to claim 20 is characterized in that, this amplifier is to be low noise amplifier.
27. wireless surrounding system according to claim 26 is characterized in that, this amplifier is to be the string stacked type amplifier.
28. wireless surrounding system according to claim 27 is characterized in that, this amplifier comprises:
One first inductance is coupled to this input;
One the 5th electric capacity is coupled between this first inductance and the Section Point;
One second inductance is coupled between this voltage source and this first output;
One the 3rd transistor has one the 3rd grid that is coupled to this Section Point, is coupled to one the three the first utmost point of this first output, and one the three the second utmost point; And
One the 3rd inductance is coupled between the three the second utmost points and this earth point.
29. wireless surrounding system according to claim 28 is characterized in that, this amplifier more comprises one the 4th transistor, is coupled between this first output and the 3rd transistorized the three the first utmost points, and has one the 4th grid, is coupled to this voltage source.
30. wireless surrounding system according to claim 28 is characterized in that this amplifier more comprises a bias generator, is biased into this Section Point in order to apply one.
31. wireless surrounding system according to claim 30 is characterized in that, this amplifier more comprises one the 3rd resistance, is coupled between this bias generator and the Section Point.
32. wireless surrounding system according to claim 20 is characterized in that, this second output and the 3rd output are the signals of output low noise coefficient and high-gain.
33. wireless surrounding system according to claim 20 is characterized in that, this second output and the 3rd output are to be coupled to one first signal input part and the secondary signal input that an image signal is eliminated frequency mixer respectively.
34. wireless surrounding system according to claim 33 is characterized in that, more comprises:
One the 3rd electric capacity is coupled between this second output and this first signal input part; And
One the 4th electric capacity is coupled between the 3rd output and this secondary signal input.
35. wireless surrounding system according to claim 1 is characterized in that, this demodulator circuit comprises:
One first demodulation module, in order to this first processing signals is carried out demodulation, to produce one first restituted signal, this first demodulation module comprises:
One first band pass filter carries out phase deviation to this first processing signals;
One first automatic corrective loop is coupled to this first band pass filter, is used for proofreading and correct the centre frequency of this first band pass filter to fix the phase deviation of this first band pass filter to this first processing signals of input;
One first phase comparator, the relatively phase difference of first processing signals after this first processing signals and the phase deviation, and output result relatively; And
One second demodulation module, in order to this second processing signals is carried out demodulation, to produce one second restituted signal, this second demodulation module comprises:
One second band pass filter carries out phase deviation to this second processing signals;
One second automatic corrective loop is coupled to this second band pass filter, is used for proofreading and correct the centre frequency of this second band pass filter to fix the phase deviation of this second band pass filter to this second processing signals of input; And
One second phase comparator, the relatively phase difference of second processing signals after this second processing signals and the phase deviation, and output result relatively.
36. wireless surrounding system according to claim 35, it is characterized in that, this first band pass filter and this first automatic corrective loop are made of components identical, and this second band pass filter and this second automatic corrective loop are made of components identical.
37. wireless surrounding system according to claim 36 is characterized in that, this first band pass filter is to be first mutual conductance-capacitive filter, and this second band pass filter is to be second mutual conductance-capacitive filter.
38. wireless surrounding system according to claim 36 is characterized in that, this first automatic corrective loop comprises:
One first oscillator is used for producing one first with reference to clock signal;
One first integrator is coupled to this first oscillator, and this first integrator is to be used for first producing one first output amplitude with reference to clock signal and one first operating voltage according to this;
One first amplitude comparator, it has one the 3rd input is to be coupled to this first integrator, and one four-input terminal be to be coupled to this first oscillator, this first amplitude comparator is used for relatively this first output amplitude of this first integrator and this first amplitude with reference to clock signal of this first oscillator, and exports one first comparative result; And
One first operating voltage adjuster, it has an input is to be coupled to this first amplitude comparator, and one output be to be coupled to this first integrator, this first band pass filter, this first operating voltage adjuster is to be used for inputing to according to this first comparative result adjustment of this first amplitude comparator output this first operating voltage of this first integrator and this first band pass filter.
39., it is characterized in that this second automatic corrective loop comprises according to the described wireless surrounding system of claim 38:
One second oscillator is used for producing one second with reference to clock signal;
One second integral device is coupled to this second oscillator, and this second integral device is to be used for second producing one second output amplitude with reference to clock signal and one second operating voltage according to this;
One second amplitude comparator, it has one the 5th input is to be coupled to this second integral device, and one the 6th input be to be coupled to this second oscillator, this second amplitude comparator is used for relatively this second output amplitude of this second integral device and this second amplitude with reference to clock signal of this second oscillator, and exports one second comparative result; And
One second operating voltage adjuster, it has an input is to be coupled to this second amplitude comparator, and one output be to be coupled to this second integral device, this second band pass filter, this second operating voltage adjuster is to be used for inputing to according to this second comparative result adjustment of this second amplitude comparator output this second operating voltage of this second integral device and this second band pass filter.
40. according to the described wireless surrounding system of claim 39, it is characterized in that, this first integrator has one first single gain frequency, this first output amplitude is corresponding to this first single gain frequency, this second integral utensil has one second single gain frequency, and this second output amplitude is corresponding to this second single gain frequency.
41. according to the described wireless surrounding system of claim 40, it is characterized in that, this of this first integrator first single gain frequency is the centre frequency corresponding to this first band pass filter, and this second single gain frequency of this second integral device is the centre frequency corresponding to this second band pass filter.
42., it is characterized in that this first integrator comprises according to the described wireless surrounding system of claim 39:
One first trsanscondutor is coupled to this first oscillator and this first operating voltage adjuster, is used for according to this producing one first drive signal first with reference to clock signal and this first operating voltage; And
One first electric capacity is coupled to this first trsanscondutor, is used for discharging and recharging according to this first drive signal, produces this first output amplitude.
43., it is characterized in that this second integral device comprises according to the described wireless surrounding system of claim 42:
One second trsanscondutor is coupled to this second oscillator and this second operating voltage adjuster, is used for according to this producing one second drive signal second with reference to clock signal and this second operating voltage; And
One second electric capacity is coupled to this second trsanscondutor, is used for discharging and recharging according to this second drive signal, produces this second output amplitude.
44. wireless surrounding system according to claim 36 is characterized in that, this demodulator circuit more comprises:
One first analog-to-digital converter is coupled to this first phase comparator, is used for converting the result of this first phase comparator output to this first restituted signal; And
One second analog-to-digital converter is coupled to this second phase comparator, is used for converting the result of this second phase comparator output to this second restituted signal.
CNU2007201486525U 2007-04-29 2007-04-29 Wireless surrounding system Expired - Lifetime CN201063858Y (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102625227A (en) * 2011-01-26 2012-08-01 宏正自动科技股份有限公司 Signal extension system and transmitting end and receiving end thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102625227A (en) * 2011-01-26 2012-08-01 宏正自动科技股份有限公司 Signal extension system and transmitting end and receiving end thereof

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