CN1304229A - Radio sound transmitting equipment - Google Patents
Radio sound transmitting equipment Download PDFInfo
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- CN1304229A CN1304229A CN 99125823 CN99125823A CN1304229A CN 1304229 A CN1304229 A CN 1304229A CN 99125823 CN99125823 CN 99125823 CN 99125823 A CN99125823 A CN 99125823A CN 1304229 A CN1304229 A CN 1304229A
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Abstract
A radio sound transmission transmitting equipoment includes: voice processing, modulating, keyboard control of oscillating and radio frequency portions. The voice processing portion possesses the voice frequency amplification circuit which can use CPU unit to control its gain, control feedback quantity according to code signal of CPU unit and regulate the amplitude of voice signal, and the phase-shift circuit for phase-shifting output signal of balancer to make it lag at 90 deg. The keyboard control oscillating portion includes: transmitting frequency setting function keyboard, CPU unit and phase-lockel loop for controlling its frequency point. The modulating portion can make direct frequency modulation or indirect frequency modulation according to the voice frequency signal intensity and weakness. Said invention can set frequency point in the range of 1-1000 MHz, and can eliminate whistling of radio mike.
Description
The present invention relates to a kind of Wireless Telecom Equipment, particularly a kind of radio sound transmitting equipment.
Existing wireless microphone equipment is made up of speech processing section, modulating part, oscillating part, radio frequency part usually, and voice signal is handled by amplitude modulation or frequency modulation, transmits with wireless mode.Therefore wireless microphone is suitable for various environment, is particularly suitable for using in environment such as teaching, report, interview, performance, Karaoke.Yet existing wireless microphone equipment (has only 1-8 fixedly frequency at most) usually in the 88-108MHZ frequency range point takes place frequently and penetrates FM signal, can not change transmitting channel in wideer frequency range according to user's wish.On the other hand, existing wireless microphone equipment is relatively poor to the ability of the self-adaptive processing of the voice signal that picks up, if the user near microphone talk be easy to generate the whistle, if away from microphone talk, then noise increases and maybe can not transmit voice signal.
The purpose of this invention is to provide a kind of radio sound transmitting equipment that can eliminate whistle cry and can in the wider frequency segment limit, put frequency arbitrarily.
The object of the present invention is achieved like this, and radio sound transmitting equipment comprises: speech processing section, modulating part, Keyboard Control oscillating part, radio frequency part; The speech processing section comprises: flow-guiding mouth; Microphone: preemphasis circuit is characterized in that: the speech processing section also comprises a phase-shift circuit, to the equalizer output signal phase shift, makes its quadrature lagging; With the audio amplifier circuit of being controlled its gain by CPU element, it controls its feedback quantity according to the code signal of CPU element, to adjust the amplitude of audio signal; Modulating part is carried out frequency modulation with the audio signal of height vocal cores bandpass filter output to the carrier signal of oscillating part output and is handled, when this audio frequency signal amplitude is strong, directly carry out frequency modulation, when a little less than this audio frequency signal amplitude, utilize the frequency of this signal just to carry out indirect frequency modulation; The Keyboard Control oscillating part comprises: tranmitting frequency is provided with function keyboard, CPU element, status displays, the frequency division phase discriminator, filtering and voltage-controlled part, oscillating circuit, amplifying circuit, frequency division phase discriminator wherein, filtering and voltage-controlled part, oscillating circuit, amplifying circuit constitutes a phase-locked loop, when tranmitting frequency is provided with function key to frequency division value of CPU element input, CPU element changes into the binary system divider ratio according to this frequency division value, the frequency division phase discriminator produces a direct voltage under this frequency division value control, giving voltage-controlled element after filtering changes its capacity, oscillating circuit is changed with the volume change of voltage-controlled element, oscillator one tunnel output is sent the frequency division phase discriminator back to and is carried out phase demodulation after amplifying, thereby the phase-locked loop is locked on the predetermined frequency, make oscillating circuit produce a stable oscillator signal, give modulation circuit through another road with preset frequency.
In addition, CPU element is the radio-frequency power amplification and the push mechanism power supply of radio frequency part according to keyboard input instruction control controlled source, makes complete machine be in emission state.
CPU element is used for channel frequency, the volume of receiver control, the coded data of noise elimination position according to the keyboard input instruction to modulating part output.
The speech processing section is provided with an equalizer, is used for the output signal of audio frequency amplifier is made equilibrium treatment.
The speech processing section also is provided with a height vocal cores bandpass filter, and the 30KHZ high frequency whistle that is used for filtering phase-shift circuit output signal is composition and the following low-frequency ac composition of 50HZ.
Radio frequency part comprises buffer amplifier, exciting circuit, promotion circuit, rf power amplifier circuit, filter circuit and transmission feeder line, is used for wireless mode emission FM signal.
Advantage of the present invention is: (it changes transaudient direction to adopt air deflector, adjust feedback quantity, signal before amplifying is postponed and cushions, making it can produce best signal amplifies, apply for a patent separately) handle sound signal and voice signal is postponed processing by phase-shift circuit, this signal of postpone handling makes strong and weak signals obtain balanced modulation output through the direct frequency modulation and the indirect frequency modulation of modulation circuit, thus eliminated the excessive and whistle of causing of volume.Owing to adopt the phase-locked loop oscillating circuit of controlling by CPU, therefore can in 1-1000M HZ frequency range, frequency be set continuously on the other hand.In addition, channel-changing, volume, noise elimination position and the start/shutdown that the encoding setting by CPU element can also remote-control receiver.
Describe the present invention below in conjunction with accompanying drawing.
Fig. 1 is the integrally-built circuit block diagram of explanation the present invention;
Fig. 2 is the circuit diagram of phase-shift circuit among Fig. 1, the moving filter of height vocal cores, modulating part, phase-locked loop and radio frequency part;
Fig. 3 is the circuit diagram of microphone among Fig. 1, preemphasis circuit, equalizer, CPU element, controlled source, stabilized voltage power supply.
Fig. 4 is the equivalent electric circuit of indirect frequency modulation;
Fig. 5 is the equivalent electric circuit of direct frequency modulation.
Referring to Fig. 1, radio sound transmitting equipment of the present invention comprises: speech processing section, modulating part, Keyboard Control oscillating part and radio frequency part.
The speech processing section comprises among Fig. 1: flow-guiding mouth; Microphone: preemphasis circuit; Audio amplifier circuit; Equalizer; Phase-shift circuit and height vocal cores bandpass filter.Preliminary treatment is carried out to the voice signal that picks up through flow-guiding mouth, microphone in the speech processing section, and wherein voice signal is amplified by audio amplifier circuit after preemphasis is handled.Audio amplifier circuit is controlled its feedback quantity according to the code signal of CPU element, output amplitude with automatic adjustment audio signal, promptly, when the audio frequency amplifier output signal is excessive, give CPU element through A/D converter, CPU element outupt coded signal after adjudicating, this code signal are delivered on the negative feedback branch road of audio frequency amplifier through D/A converter, feedback quantity is increased, and gain reduces; When the audio frequency amplifier output signal is too small, give CPU element through A/D converter, CPU element outupt coded signal after adjudicating, this code signal is delivered on the negative feedback branch road of audio frequency amplifier by D/A converter, feedback quantity is reduced, gain is risen, thereby has adjusted the output amplitude of audio signal automatically.Audio signal after the amplification is made equilibrium treatment by equalizer, then by the phase-shift circuit phase shift, makes its quadrature lagging.Fig. 3 shows the physical circuit as the microphone of the speech processing section of an example, preemphasis circuit, equalizer.Audio frequency enters through mechanical air deflector (by its size of streamline gate control, change its direction by guide ring, adjust its weight by mozzle, apply for a patent separately), delivers to microphone after preliminary treatment.The signal of telecommunication after the conversion (audio frequency), deliver to operational amplifier IC2 (comprising dual-stage amplifier) and amplify through input adjustment potentiometer W1, capacitor C 1, preemphasis circuit R1, C2, in order to cooperate the even of signal power, the signal after the amplification is done an amplitude limit adjustment by the potentiometer W2 as equalizer again.Audio amplifier circuit is made up of operational amplifier IC2 and peripheral circuit, when the complete machine feedback quantity is excessive or too small, the output signal of audio frequency amplifier is given the 16th pin of CPU element IC4 through modulus converter A/D, since keyboard prefabricated certain encoding state, after handling, single-chip microcomputer IC4 gives digital to analog converter DA from code signal of IC4 the 17th pin output, converting aanalogvoltage to is added between diode D6 and the thermistor RT, change operational amplifier IC2 the 6th pin and the 7th pin resistance value according to this aanalogvoltage, change the size of its amount of negative feedback, thereby reach the purpose of adjusting modulation sensitivity.The 5th pin of IC2 is the audio signal input end of having handled, the 7th pin is the output of first order amplifier, the 6th pin is the negative feedback end of first order amplifier, and the proper signal after controlling is automatically given second level amplifier again and imported from the 2nd pin, amplifies the back and exports from the 1st pin.Fig. 2 shows the circuit of phase-shift circuit and height vocal cores bandpass filter.Resistance R 1, capacitor C 3 constitute phase-shift circuit, make through amplifying signal to lag behind 90 °, and height vocal cores bandpass filter is made up of two electric capacity and resistance R 3-R5, and the 30KHZ high frequency whistle that is used for filtering phase-shift circuit output signal is composition and the following low frequency composition of 50HZ.
The Keyboard Control oscillating part comprises among Fig. 1: tranmitting frequency is provided with function keyboard, CPU element, status displays, the frequency division phase discriminator, filtering and voltage-controlled part, oscillating circuit, amplifying circuit, frequency division phase discriminator wherein, filtering and voltage-controlled part, oscillating circuit, amplifying circuit constitutes a phase-locked loop, when tranmitting frequency is provided with function key to frequency division value of CPU element input, CPU element changes into the binary system divider ratio according to this frequency division value, the frequency division phase discriminator produces a direct voltage under this frequency division value control, giving voltage-controlled element after filtering changes its capacity, oscillating circuit is changed with the volume change of voltage-controlled element, oscillator one tunnel output is sent the frequency division phase discriminator back to and is carried out phase demodulation after amplifying, thereby the phase-locked loop is locked on the predetermined frequency, make oscillating circuit produce a stable oscillator signal, and give modulation circuit through another road with preset frequency.
Referring to Fig. 2 and Fig. 3, CPU element is made of CPU IC4 shown in Fig. 3 and memory IC 1.CPU IC4 can be that the model that Motorola produces is the chip of AT89C2051 or AT89C51, the clock (Clock) that the 12nd, 13,14 pin of CPU IC4 are sent respectively, data (Data), sheet choosing (LE) isopulse signal are input to respectively with serial mode on the 9th, 10,11 pin of phase-locked ring plate IC5.The frequency division phase discriminator is made of phase-locked ring plate IC5 of MB1504 and the peripheral circuit that NEC Corporation produces.The inside prescalar of phase-locked ring plate IC5 will be to the benchmark vibration X1 frequency of IC5 the 1st, 2 pin input, carry out frequency elimination X1/N, (N is preposition divider ratio=512) obtains the channel spacing fiducial value of 25KHZ, send into through CPU IC4 generation binary coded signal by the parameter value that keyboard is inserted, reference frequency is carried out frequency multiplication.IC5 the 5th pin will be exported the scanning DC level of each correspondence with the different value state down.This DC level is through filter circuit R7, the C13 of strictness ... to R12, this pure direct voltage is added to variable capacitance diode B3, the D2 last (voltage-controlled parts) that changes the appearance value with change in voltage.
G1 is a radio-frequency field effect oscillating tube, provide power supply from R25, voltage inserts from drain electrode, and C20 is the bypass filter capacitor, and R27 and L22 are the loops of power supply and oscillator, be connected on the source electrode, the value that changes R27 can change the proper range of its oscillation amplitude, and L22 is for joining humorous inductance, and C18, C19, L23 are the LC oscillation circuit, C16 is added on the grid for the coupling input of VCO source.When loop is not locked, the scanning level that G1 sends by C16, from IC5 the 5th pin is added on D3, the D2 after stream filtering, produce a higher-order of oscillation frequency by the voltage-controlled variation of variable capacitance diode, produce a free oscillation frequency through C16 jointly to L23, C18, C19, G1, this frequency of oscillation carries out sending back to IC5 the 8th pin after high frequency amplifies through G2.IC5 the 8th pin is on the phase discriminator that is connected in the IC, if amplitude reaches certain value (for example 300MV), when inner frequency multiplication and outside oscillation signal frequency during by phase demodulation IC5 the 7th show high level, at this moment loop is lockable, what IC5 the 5th pin was exported no longer is the scan-type level, but a changeless direct voltage is fixed on this frequency G1 through VCO and vibrates, no longer drift.
Modulating part shown in Figure 1 is made of the field effect transistor G1 among Fig. 2, triode G2 and variable capacitance diode D1 and peripheral circuit.Before the audio signal of amplitude limit adjustment is being sent modulation,, make 90 ° of signal lags, as the condition that enters phase modulation at first through R1, C3 phase shift.Modulating part has indirect frequency modulation and direct frequency modulation function, directly carries out frequency modulation when this audio frequency signal amplitude is very strong; When this audio frequency signal amplitude is very weak, utilize the frequency of this signal just to carry out the phase place debugging, and then change into indirect frequency modulation.
The equivalent electric circuit of finishing the indirect frequency modulation function as shown in Figure 4.When small-signal VL sound is sent into, the audio voltage that is added on the variable capacitance diode D1 is very low, variable capacitance diode D1 is inoperative, can not produce direct frequency modulation, because the capacity very big (about 20000p) of capacitor C 2, for the approximate short circuit of audio signal, and 22 pairs of audio signal effects of inductance L also can ignore, thus the source electrode of field effect transistor G1 over the ground equivalent resistance be resistance R 27.Through R1, C3 lag behind 90 ° input signal in this circuit by phase modulation, just produce the size of skew by the frequency of input audio frequency.Finish indirect frequency modulation thus.
Its equivalent electric circuit of finishing the direct frequency modulation function as shown in Figure 5.When strong signal VH sound is sent into, the audio voltage that is added on the variable capacitance diode D1 changes greatly, variable capacitance diode D1 changes its capacitance with the variation of voltage, triode G2 and variable capacitance diode D1 and capacitor C 1, resistance R 5 constitute the direct frequency modulation circuit (because C2 capacity value is bigger, on the AC signal coupling circuit, can be similar to and be used as short circuit), audio signal VH sound amplitude size produces the size of frequency deviation.
Radio frequency part shown in Figure 1 comprises parts such as buffering amplification, excitation, promotion, radio-frequency power amplification, filtering, transmission feeder line.Fig. 2 shows its circuit structure.The buffering amplifier unit is made up of triode G3 and peripheral cell.Driver unit is made up of triode G4 and peripheral cell.Push mechanism is made up of triode G5 and peripheral cell.The radio-frequency power amplifier unit is made up of triode G6 and peripheral cell.Filter part is made up of inductance and electric capacity L5, C43, C45, L4, C46, C47, L3, C51, C48, L2, C49, L1, C50.Frequency-modulated wave through buffering amplification, excitation, promotion, power amplifier, filtering after send feeder line Y and penetrate with the wireless mode width of cloth.
Describe below that the performed frequency of CPU single-chip microcomputer presets in detail, the control of audio signal automatic gain, radio-frequency transmissions control and to the operation of receiver control.
IC4 is the CPU single-chip microcomputer, in be programmed into the function program software of 2K.R5, the C16 that 1 pin is connect is the element of usefulness of automatically reseting, and 2,3,6 pin are the keyboard instruction input, are connected to three buttons over the ground.4,5 pin connect the 4MHZ crystal oscillator, provide service conditions to single-chip microcomputer, and C17, C18 are load capacitances, can adjust frequency difference.7,8,9,10 pin connected storage IC1 are used for the access of program.12, the serial communication interface formed of 13,14 pin send data to 9,10,11 pin of Phase Lock Loop IC 5, able to programme required frequency is set.15 pin are emission control, when needs are launched, on keyboard, press the K2 key, 15 pin show high level, touch the Q1 (NPN pipe) of controlled source, make Q1 collector electrode C become low level, be added on the PNP pipe Q3 base machine by R33, make Q3 emitter and the conducting of current collection machine, power Vcc 0 is given the promotion of radio frequency part and the power input (VccO) of power amplification parts through the Q3 emitter E to Q3 collector electrode C, cause high frequency power transmitting tube work (in another embodiment, power Vcc O gives the power input (not shown) of the driver unit of radio frequency part to Q3 collector electrode C through the Q3 emitter E).Liquid crystal display simultaneously shows that with correspondence it is in emission state.
After frequency lock, IC5 7 pin present high level after Q4 oppositely amplifies, and triode Q4 collector electrode presents low level, and this low level is given CPU through IC4 the 16th pin, after CPU obtains this information, to liquid crystal display displays " CH ", represents that this signal is locked.If do not pin, be shown as " Lo ".IC4 the 17th pin provides to modulation signal amplitude size control and to the control of receiver.First kind of code signal is through D/A converter, convert the control analog quantity to, be added between IC2 the 6th to 7 pin, change its feedback resistance value through thermistor RT, diode D6 and resistance R 100, and the amplitude that reaches on certain occasion is adjusted automatically, and the modulation sensitivity scope is widened greatly.
Other four kinds of code signals of IC4 the 17th pin output are that the state of receiver control sends multiple code signal through modulating part frequency modulation.
Second kind of code signal is that receiver control changes channel frequency.
The third code signal is the volume of receiver control.
The 4th kind of code signal is the noise elimination position of receiver control.
The 5th kind of code signal is start, the shutdown of receiver control.
The D/A conversion element of these four kinds of signals of back is located on the receiver, no longer carefully states here.
IC5 the 18th, 19 send data to LCD, makes it do different demonstrations under various functional statuses.
IC3 is the low-power consumption voltage-stabilized power supply circuit.Be other circuit supply except that exciting circuit.
Each this independence of roadbed of the power supply of wireless voice transmitter complete machine of the present invention has strict LC, RC filtering measures, so that audio frequency carries quality is pure quiet, cooperates transaudient effect can reach optimum degree.
Claims (6)
1. a radio sound transmitting equipment comprises: speech processing section, modulating part, Keyboard Control oscillating part, radio frequency part;
The speech processing section comprises: flow-guiding mouth; Microphone; Preemphasis circuit is characterized in that:
The speech processing section also comprises; Control the audio amplifier circuit of its gain by CPU element, it controls its feedback quantity according to the code signal of CPU element, to adjust the amplitude of audio signal; And phase-shift circuit, to the equalizer output signal phase shift, make its quadrature lagging;
Modulating part is carried out frequency modulation with the audio signal of height vocal cores bandpass filter output to the carrier signal of oscillating part output, when this audio frequency signal amplitude is strong, directly carry out frequency modulation, when a little less than this audio frequency signal amplitude, utilize the frequency of this signal just to carry out indirect frequency modulation;
The Keyboard Control oscillating part comprises: tranmitting frequency is provided with function keyboard, CPU element, the frequency division phase discriminator, filtering and voltage-controlled part, oscillating circuit, amplifying circuit, frequency division phase discriminator wherein, filtering and voltage-controlled part, oscillating circuit, amplifying circuit constitutes a phase-locked loop, when tranmitting frequency is provided with function key to frequency division value of CPU element input, CPU element changes into the binary system divider ratio according to this frequency division value, the frequency division phase discriminator produces a direct voltage under this frequency division value control, giving voltage-controlled element after filtering changes its capacity, oscillating circuit is changed with the volume change of voltage-controlled element, oscillator one tunnel output is sent the frequency division phase discriminator back to and is carried out phase demodulation after amplifying, thereby the phase-locked loop is locked on the predetermined frequency, make oscillating circuit produce a stable oscillator signal, give modulation circuit through another road with preset frequency.
2. radio microphone equipment according to claim 1 is characterized in that: CPU element is the radio-frequency power amplification and the push mechanism power supply of radio frequency part according to keyboard input instruction control controlled source, makes complete machine be in emission state.
3. radio microphone equipment according to claim 1 is characterized in that: CPU element is used for channel frequency, the volume of receiver control, the coded data of noise elimination position according to the keyboard input instruction to modulating part output.
4. radio microphone equipment according to claim 1 is characterized in that: the speech processing section is provided with an equalizer, is used for the output signal of audio frequency amplifier is made equilibrium treatment.
5. radio microphone equipment according to claim 1 is characterized in that: the speech processing section also is provided with a height vocal cores bandpass filter, and the 30KHZ high frequency whistle that is used for filtering phase-shift circuit output signal is composition and the following low-frequency ac composition of 50HZ.
6. radio microphone equipment according to claim 1 is characterized in that: radio frequency part comprises buffer amplifier, exciting circuit, promotion circuit, rf power amplifier circuit, filter circuit and transmission feeder line, is used for wireless mode emission FM signal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB991258231A CN1157874C (en) | 1999-11-24 | 1999-11-24 | Radio sound transmitting equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB991258231A CN1157874C (en) | 1999-11-24 | 1999-11-24 | Radio sound transmitting equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1304229A true CN1304229A (en) | 2001-07-18 |
| CN1157874C CN1157874C (en) | 2004-07-14 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB991258231A Expired - Fee Related CN1157874C (en) | 1999-11-24 | 1999-11-24 | Radio sound transmitting equipment |
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| Country | Link |
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| CN (1) | CN1157874C (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102595069A (en) * | 2012-01-21 | 2012-07-18 | 中广传播集团有限公司 | Equipment and method for debugging single frequency network |
| CN106231502A (en) * | 2016-08-29 | 2016-12-14 | 广州声姆音响设备有限公司 | The frequency response method of reduction treatment of a kind of phase-shift circuit and circuit |
| CN106707867A (en) * | 2016-12-30 | 2017-05-24 | 脉创测控装备科技（苏州）有限公司 | Device and method for regulating and controlling audio signal based on D/A converter |
-
1999
- 1999-11-24 CN CNB991258231A patent/CN1157874C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102595069A (en) * | 2012-01-21 | 2012-07-18 | 中广传播集团有限公司 | Equipment and method for debugging single frequency network |
| CN102595069B (en) * | 2012-01-21 | 2017-02-22 | 中广传播集团有限公司 | Equipment and method for debugging single frequency network |
| CN106231502A (en) * | 2016-08-29 | 2016-12-14 | 广州声姆音响设备有限公司 | The frequency response method of reduction treatment of a kind of phase-shift circuit and circuit |
| CN106231502B (en) * | 2016-08-29 | 2019-04-26 | 广州声姆音响设备有限公司 | A kind of the frequency response method of reduction treatment and circuit of phase-shift circuit |
| CN106707867A (en) * | 2016-12-30 | 2017-05-24 | 脉创测控装备科技（苏州）有限公司 | Device and method for regulating and controlling audio signal based on D/A converter |
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| Publication number | Publication date |
|---|---|
| CN1157874C (en) | 2004-07-14 |
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