CN2400973Y - Four-track large-power infrared transmitting and receiving system - Google Patents

Abstract

The utility model relates to a system with a four-channel infrared receiver and a four-channel high-power infrared transmitter which can expand transmitting power. The existing traditional design way is canceled; namely, the system does not use a way of a plurality of different carrier frequencies (or subcarrier frequencies) to convey different voice signals, but a way of pulse position modulation (PPM for short). In the PPM way, four voice signals are modulated on a homogeneous series of coded pulses and conveyed out in an infrared transmitting way. Likewise, the infrared receiver also recovers signals conveyed by the transmitter into sound in the PPM decoding way. Because of the adoption of the PPM coding/decoding technique, the high-power transmitter and the receiver of the utility model have the characteristics of simple circuit structure, no need of timing, easy connection and use, etc.

Description

Emission of quadraphony Infrared High-Power and receiving system

The utility model relates to a kind of quadraphony and can expand the Infrared High-Power transmitter and the quadraphony infrared receiving set system of transmitting power.

Existing infrared emission and receiving system transmit multichannel sterego information or transmit multiple voice signal simultaneously, often adopt a plurality of independently carrier frequency passage infrared transmitters and infrared FM receiver.As a convention four kinds of language of need interpreting, then need four independently carrier frequency passage infrared transmitter and infrared FM receiver.Though the circuit structure of each transmitter and receiver is basic identical, owing to be operated in different carrier frequency frequencies separately, circuit more complicated, production adjustment trouble.Be stressed that especially this emission and receiving system are in order to improve audibility, the reflector of a plurality of different channels often needs to be installed in the place than higher, causes the transmission stube cable many, and installation and use are very inconvenient.

The purpose of this utility model provides a kind of quadraphony Infrared High-Power emission and receiving system, and its circuit structure is simple, adjustment and easy to use.

The utility model is made up of the quadraphony infrared transmitter and the quadraphony infrared receiving set that adopt the pulse position modulation mode.Quadraphony infrared transmitter is made of main frame and two separate units of secondary machine, wherein secondary machine is the Infrared High-Power reflector, and main frame is by four identical audio track circuit, pulse position modulation (pulse positionMcdulation, hereinafter to be referred as PPM) coding circuit and buffering amplifying circuit be connected in sequence, and signal between main frame and secondary machine transmission only coaxial cable of need is finished.The audio track circuit is connected in sequence by pre-amplification circuit, the anti-tampering filter network of dual input circuit, audio mix circuit, band ALC function.The Infrared High-Power reflector is equipped with synchronous input and synchronous accessory power outlet, when needing expansion infrared emission power, as long as successively synchronous accessory power outlet is connected with the synchronous input socket of next reflector, can realize the synchronized transmissions of a plurality of reflectors with coaxial cable.Quadraphony infrared receiving set is by the pulse pre-amplification circuit of photoelectricity receiving circuit connecting band AGC successively, pulse position modulation decoding circuit, power amplification circuit and loudspeaker or earphone.

In the main frame of quadraphony infrared transmitter, the voice signal of being sent here by microphone or other sources of sound is through the dual input circuit and after the audio mix circuit mixes, be sent to the pre-amplification circuit of band ALC function, again through anti-tampering filter network, be sent to the PPM coding circuit with the input signal of other three audio tracks.The coded pulse that PPM coding circuit output is modulated is sent to via a coaxial cable and pinnacled Infrared High-Power reflector to be installed to be launched after buffer amplifier circuit amplification, shaping and impedance matching.

In quadraphony infrared receiving set, the PPM signal is received by the photoelectricity receiving circuit after the pulse pre-amplification circuit of band AGC amplifies, and send the PPM decoding circuit to decode, and selects the sound channel signal that will listen to, and ear sending machine or loudspeaker pass to people's ear after amplifying.

Owing to adopt a series of coded pulse to realize the transmission of four different phonetic signals (quadraphony), each sound channel does not need independent reflector, receiving circuit also saves general receiver inductance coil (as middle week, high frequency coil etc.) commonly used, circuit is simplified greatly, production process does not need to resemble carries out the circuitry adjustment the carrier-frequency circuit, is convenient to produce in enormous quantities and reduce cost.Install and use also very convenient.

Below in conjunction with accompanying drawing the utility model is described in further detail.

Fig. 1 is quadraphony infrared emission machine circuit connection box figure.

Fig. 2 is a PPM coding circuit connection layout.

Fig. 3 is that quadraphony infrared receiving set circuit connects block diagram

Fig. 4 is a PPM decoding circuit connection layout.

Among Fig. 1, the input circuit 1 of first sound channel and input circuit 2 formed the dual input circuit and mixed through audio mix circuit 3 in the main frame 20, thereafter the pre-amplification circuit 4 of connecting band ALC function, enter an input of PPM coding circuit 6 through anti-tampering filter network 5, second and third, quadraphony circuit 10,11,12 and the first sound channel circuit be identical, import three inputs in addition of PPM coding circuit 6 respectively, after amplifying by buffer amplifier circuit 7 again, couple together by a coaxial cable 8 and the secondary machine 9 (being the Infrared High-Power reflector) of hanging in height.By the PPM signal of buffer amplifier circuit 7 outputs,,, drive outwards emission PPM infrared pulses of Infrared High-Power radiating circuit 17 again through buffer amplifier circuit 14 and promotion circuit 16 through the synchronous input socket 13 of the secondary machine 9 of coaxial cable 8 accesses.The output of buffer amplifier circuit 14 is connected to synchronous accessory power outlet 15 in addition, connects the usefulness of another reflector when being used for needs expansion transmitting power.The pre-amplification circuit 4 of band ALC function can adopt integrated circuit KA2220.PPM coding circuit 6 is made up of PPM coding integrated circuit and peripheral cell, and the built-in function of PPM coding integrated circuit comprises pulse distribution/modulation, vibration, amplification, triggering and tri-state buffer circuit.

Among Fig. 2, connect transistor Q1, Q2, Q3, Q4 base stage through capacitor C1, C2, C3, C4 respectively by the quadrophonic output signal in front, the emitter of Q1, Q2, Q3, Q4 lands through resistance R 7, R8, R9, R10 respectively, collector electrode connects 1,2,3,4 inputs of PPM coding integrated circuit (IC) 2 respectively, and is landed by R11, R12, R13, R14 respectively; Four sound channel signals are assigned with the different pulses in the modulation " assembled pulse " among the IC2, again by IC2 the 9th pin output modulated " assembled pulse " signal, IC2 the 9th pin connects transistor Q5 base stage through C8, R17, after Q5 amplification, shaping and impedance matching, export by the Q5 collector electrode, 10,11,12,13 pin of IC2 and C6, the R15 of peripheral cell thereof and R16 form clock oscillation circuit and are used to produce a series of " assembled pulses ", the 17th pin is for starting (triggering) signal input part, and its signal is taken from the input speech signal of each sound channel amplifying circuit.When phonetic entry, the circuits for triggering of IC2 inside start each functional circuit work, 9 pin output PPM signal.Integrated circuit (IC) 2 inner 31 is trigger (trigger), and 32 is modulator (Divider/moduletor), and 33 is buffer (3atate/bufter).In case voice signal disappears, the external delay capacitor C7 of 16 pin makes circuit through after the delay of certain hour, and IC2 stops output pulse signal.

Among Fig. 3, photelectric receiver DR is access to the preposition amplification circuit IC3 of pulse of band AGC, and IC4 connects Yang Sheng device 18 again through the PPM decoding integrated circuit.Photelectric receiver DR can adopt photodiode.IC4 inside comprises that pre-amplification (P-IF), four-way pulse detection (4 CH DET1), synchronous circuit (SYNC), four select a channel selector switch (INSW), detecting circuit (DET2) and power amplifier (AMP).

Among Fig. 4, the PPM signal of sending here from IC3 enters pre-amplifying circuit through 18 pin of IC4, signal after the amplification is sent to four-way pulse detection circuit (4 CH DET1) and synchronous circuit (SYNC) respectively, PPM signal with corresponding four sound channels under the two effect detects, pass through channel selection circuit (INSW) again, select the modulating pulse of one of them sound channel by external push-button switch S1, be sent to the speech signal that detection 2 (DET2) demodulates corresponding sound channel, export from 6 pin, and then after sending into the amplification of 7 pin power amplifiers, promote loudspeaker and be reduced to sound.IC4 the 10th, 14 pin are the power supply input, and 20 pin (VDD2) output, one direct current voltage stabilizing is through peripheral cell some functional circuit power supply in IC4.1 pin is set the starting level of noise elimination by outer meeting resistance R21,19 pin are by the pre-incoming level that amplifies in the outer meeting resistance R22 control, 2 pin outer meeting resistance R23 are used to make synchronous circuit to be in optimum state, but, during actual the use R23 is set in a fixed value because synchronous circuit has certain " catching range ".The external noise elimination output filter capacitor of 3 pin C22, the external push-button switch S1 of 17 pin is used to select to listen to the voice signal of different sound channels, and external detection resistance R 24,7,8 pin of 5 pin are the power amplifier input, and 9 pin are the power amplifier output.VR1 is a volume control potentiometer.

Claims (2)

1, a kind of quadraphony Infrared High-Power emission and receiving system, it is characterized in that this system is made up of the quadraphony infrared transmitter and the quadraphony infrared receiving set that adopt the pulse position modulation mode, quadraphony infrared transmitter is made of main frame and two unit of secondary machine, wherein secondary machine is the Infrared High-Power reflector, and main frame is connected in sequence by four identical audio track circuit, pulse position modulation coding circuit, buffer amplifier circuits, and the signal transmission between main frame and the secondary machine only needs a coaxial cable to finish; Quadraphony infrared receiving set receives road pulse pre-amplification circuit, pulse position modulation decoding circuit, power amplification circuit and loudspeaker or the earphone of connecting band AGC successively by photoelectricity.

2, a kind of quadraphony Infrared High-Power emission as claimed in claim 1 and receiving system, the circuit that it is characterized in that described quadraphony infrared transmitter is connected to: the input circuit 1 of first sound channel and input circuit 2 formed the dual input circuit and mixed through audio mix circuit 3 in the main frame 20, thereafter the pre-amplification circuit 4 of connecting band ALC function, enter an input of PPM coding circuit 6 through anti-tampering filter network 5, second, three, quadraphony circuit 10,11,12 and the first sound channel circuit is identical, import three inputs in addition of PPM coding circuit 6 respectively, after amplifying by buffer amplifier circuit 7 again, couple together by a coaxial cable 8 and the secondary machine 9 of hanging in height; By the PPM signal of buffer amplifier circuit 7 outputs,,, drive outwards emission PPM infrared pulses of Infrared High-Power radiating circuit 17 again through buffer amplifier circuit 14 and promotion circuit 16 through the synchronous input socket 13 of the secondary machine 9 of coaxial cable 8 accesses; The circuit of quadraphony infrared receiving set is connected to: photelectric receiver DR is access to the preposition amplification circuit IC3 of pulse of band AGC, and IC4 connects Yang Sheng device 18 again through the PPM decoding integrated circuit.

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