CN1023050C - Receiving and transmitting device for automatic continuous signal of long distance telephone call - Google Patents

Abstract

The present invention relates to a device for receiving and forwarding automatic connection signals of a long distance telephone call. A two-tone high frequency subscriber mode is used in circuits for signal transmission; after signal reception and signal forwarding, semiautomatic or fully automatic services can be started in the circuits. The device is composed of a dialing tone notch filter, the input circuits, a two-tone receiver, a busy tone decoder for off-hook and on-hook, and corresponding control and forwarding units. A large quantity of integrated circuits are used so that the circuits have the advantages of stable and reliable performance and convenient use.

Description

Receiving and transmitting device for automatic continuous signal of long distance telephone call

The present invention relates to a kind of telecommunication communication technology, more particularly, what it related to is a kind of receiving and retransmitting device of automatic continuous signal of long distance telephone call.

In the area of using carrier wave and microwave transmission circuit, want to open long-distance automatically or semi-automatic telephone just must be converted to carrier terminal equipment from user's direct current signals such as the line is busy, dial and take out stitches transmits needed AC signal.

At present, no matter be that subscribers feeder system is semi-automatic, point-to-point full-automatic, still adopt the startup release signal of register(system) multiple-frequency signal transmission DD series all to adopt one frequency system, and the DC pulse of recovering whether standard be by the simple signal quality decision that receives.So even the signal that sends is very accurate, through after the long-distance circuit transmission, also unavoidably can disturbed distortion or change often etc.Because these unfavorable factors have influenced the quality of the pulse signal that restores, in communication the wrong number that continues can appear therefore, and do not tear line open or account for serious problems such as do not reach the standard grade.

In addition, in the equipment that adopts single-frequency, receiving loop sensitivity is high more, and speech is just big more to the influence in this loop, and the mistake proofing ability is also just poor more, and changing of the relative positions chance is also just many more.So the remolding sensitivity of present toll circuit automatic connection machine is lower, this low sensitivity makes its having relatively high expectations to the toll circuit quality.

The object of the present invention is to provide a kind of receiving and retransmitting device that adapts to the automatic continuous signal of long distance telephone call of common toll circuit use.It does not have specific (special) requirements to toll circuit, even can open the semi-automatic dial business of toll telephone on the relatively poor toll circuit of communication quality yet.Because transmission of control signals has adopted the multifrequency subscriber signaling,, improved the reliability of communication so overcome the drawback of one frequency system.Simultaneously, circuit design of the present invention is reasonable, and machine volume is little, and is in light weight, is convenient to safeguard.

The receiving and retransmitting device of automatic continuous signal of long distance telephone call of the present invention comprises first a port 20a who is connected with carrier terminal equipment two ends, second a port 20b who is connected with local call office, and be the power supply 32 of each unit power supply, it is characterized in that:

A dialing tone trap wave unit 21 and a dislodging machine pulse transmitting unit 31 are connected in series between first port 20a that states and the described second port 20b.

An input circuit 22 is connected across on the described first port 20a with high impedance;

A double audio receiving unit 23 is used for receiving the signal that remote subscriber sends through described input circuit 22, and converts double-audio signal to four binary code;

An off-hook decoding unit 25, be used to receive and translate the dislodging sign indicating number of sending from described double audio receiving unit 23, make described dislodging machine pulse transmitting unit 31 transmit the off-hook pulses through off-hook control unit 29 and pulse generation retransmission unit 28 again, and described dialing tone trap wave unit 21 is inserted with high impedance;

Described double audio receiving unit 23 produces retransmission unit 28 with described pulse and is connected, and is used to transmit dialing signal;

An on-hook decoding unit 24, be used to receive and translate the on-hook sign indicating number of sending from described double audio receiving unit 23, through hang up control unit 30 controls, described off-hook control unit 29, pulse generation retransmission unit 28 and dislodging machine pulse transmitting unit 31 are resetted again;

A busy tone decoding unit 26, be used for receiving busy-back signal from dislodging machine pulse transmitting unit 31, make described hang up control unit 30 through busy tone automatic control unit 27 again, off-hook control unit 29, pulse produces retransmission unit 28 and dislodging machine pulse transmitting unit 31 resets.

With reference to secondary figure device of the present invention is described further below and explained, wherein:

Fig. 1 shows a long distance communication circuit with apparatus of the present invention.

Fig. 2 shows the block diagram of apparatus of the present invention.

Fig. 3 a and Fig. 3 b have constituted a physical circuit figure who realizes apparatus of the present invention.

In the long distance communication circuit shown in Fig. 1, remote subscriber 15 joins with carrier terminal equipment B14, and this remote subscriber 15 can be the telephone subscriber with dual-tone dialing function, also can be the double-tone frequency push-button dialling pad of preparing on the seat.Apparatus of the present invention 12 connect and carrier terminal equipment A13 and local call office 11 between.Like this, by bottom to the further describing of apparatus of the present invention, just can realize remote subscriber direct dialing local user's function.Here should be pointed out that especially that said remote subscriber 15 and local call office 11 also can be a Local Exchange, private branch exchange, toll or a telephone set.

In the block diagram of the apparatus of the present invention shown in Fig. 2, double audio receiving unit 23 receives the signal that is sent by remote subscriber by input circuit 22, and double-audio signal converted to four binary code, its remote subscriber utilizes the operation of " * " on the keypad to carry out off-hook, utilizes the operation of " # " to carry out on-hook.Input circuit 22 is connected across on the first port 20a of apparatus of the present invention with the high impedance form.When user's off-hook, off-hook decoding unit 25 translates from the off hook signal of double audio receiving unit 23 (the off-hook sign indicating number is 1011), and produce retransmission unit 28 through off-hook control unit 29 control impuls and make off-hook on-hook pulse transmitting unit 31 finish the off-hook pulse to transmit, dialing tone trap wave unit 21 high impedances are got involved, and when first dial impulse arrives, automatically terminated.Double audio receiving unit 23 converts the remote subscriber double-tone dialing signal of receiving to the tetrad sign indicating number and gives pulse generation retransmission unit 28, converts 31 actions of pulse enable signal dislodging machine pulse transmitting unit there to, sends pulse signal to the local user.When double audio receiving unit 23 is received on-hook signal, connected on-hook decoding unit 24 translates on-hook signal (the on-hook sign indicating number is 1100), and making off-hook control unit 29 through hang up control unit 30, pulse produces retransmission unit 28 and dislodging machine pulse transmitting unit 31 resets.When busy tone decoding unit 26 when dislodging machine pulse transmitting unit is received busy-back signal, then make hang up control unit 30 by busy tone automatic control unit 27, off-hook control unit 29, pulse produces retransmission unit 28 and dislodging machine pulse transmitting unit 31 resets.Even under the user uses the situation of on-hook key, can not realize on-hook too like this.Power supply 32 will be powered for each unit in addition.

Constitutional diagram 3a(left side) and Fig. 3 b(right side) just can draw the circuit diagram of a specific embodiment of apparatus of the present invention.Wherein each unit among Fig. 2 is marked by the dotted line with same numeral in Fig. 3 a and Fig. 3 b.

Its circuit theory is:

The remote subscriber off-hook is pressed start key " * ", sends enabling signal.The enabling signal double-tone is frequently by carrier wave or microwave circuit, to double-audio signal receiving circuit 23.IC1 is 1011 binary-coded decimal output with conversion of signals.One the tunnel send IC2 to do the preparation of simulation off-hook; IC6 is sent on another road, and the 8 pin output high level of IC6 arrives 13 pin of the 6 pin output low levels of IC8 to IC2 through IC7, makes 11 pin of IC2 become high level by low level, makes the adhesive of J1 relay by the IC3 driver, connects dialing tone trap circuit 21 simultaneously.Local exchange detects off-hook.Breathing out continues sends dialing tone.Dialing tone arrives remote subscriber through trap resistance and toll circuit.(effect of trap circuit is in order to prevent the influence of strong dialing tone to IC1 reception and the remote subscriber number of sending out), remote subscriber is listened dialing tone.

After remote subscriber is heard dialing tone, press called number, telephone set or dual-tone dialing dish send double-tone subscriber signal frequently.Signal is received by IC1 through toll circuit, is converted to binary-coded decimal.IC2 is converted to the dc pulse signal of standard with binary-coded decimal, and pulse signal makes time pulse relay J1 inhale with pulse signal and puts through the IC3 driver, send interrupting pulse, 12 pin of IC2 output high level makes the J3 relay energized during pulse train, pulse train finishes J3 and discharges, and plays the noise elimination effect.When IC2 sent the first item sign indicating number, J2 inhaled moving the maintenance by IC7, IC10, IC3.Remove the dialing tone trap circuit, improve receiving sensitivity and the influence of avoiding the conversation level.The remote subscriber number of sending out is because be the double-tone frequency, and speed is very fast, so this device has memory function, makes to receive with the forwarding pulse and carries out simultaneously, error code can not take place.

After Local Exchange harvests called number, carry out incoming call and continue, continuing finishes, and called off-hook can be conversed.

Talk-through, if the on-hook of the user of the other side Local Exchange elder generation, IC4 receives busy-back signal, 8 pin output impulse level, through the shaping of IC9 gate circuit, the IC11 time-delay is counted it by IC5, and the output high level is through gate circuit IC8, IC9,4 pin output high level by IC9, latch cicuit IC5, IC6 are carried out zero clearing, relay J 1, J2 are not had keep level and discharge circuit restoration.If not on-hook of the user of Local Exchange, the on-hook of remote subscriber elder generation.Remote subscriber will put the cell phone then by " # " key.Apparatus of the present invention are received on-hook signal, and IC1 receives and is decoded into the 1100BCD sign indicating number, the 6 pin output high level of IC6, and the 12 pin output low levels of gate circuit IC8 are exported high level by 4 pin of IC9 the circuit zero clearing are restored, and the other side listens the busy tone on-hook to restore.Do when called when remote subscriber, Local Exchange sends the 25HZ ringing signal, and to remote subscriber, this ringing-current is subjected to Local Exchange's ringing-current discontinuous control through long-distance electricity (line) road.User's bell ring off-hook can be replied by " * " key (J1 inhales moving, and is the same), immediately by " 1 " key, through IC1.IC2 makes the J2 relay energized by driver IC 3.J2 inhales to employ and eliminates the problem that a J1 inhales moving conversation voice little (removing dialing tone trap wave unit 21), makes speaking circuit keep operate as normal, words Bi Fuyuan.

Though inner 350HZ and two trap circuits of 440HZ of being provided with of the IC1MT8870 that this device double audio receiving unit 23 uses are difficult to overcome to the influence of the strong dialing tone of 450HZ.

For ringing-current is normally passed through, after circuit was received off hook signal, when listening dialing tone, trap resistance added entry loop.This circuit is added in loop impulse and sends between loop and the MT8870 receiving loop, so neither influences the transmission of loop impulse, does not influence the reception of double-audio signal again.After circuit was received the first item coded signal, trap circuit remained to words eventually, so talking path is had no effect promptly by short circuit always.This trap circuit 21 has the resistor of a 20K Ω.When sending loop impulse, normally receive for making MT8870, so utilize the noise elimination principle, will send with receiving loop and separate, avoid influencing each other.

In addition, by normal running, after using double tone multiple frequency telephone set to make a call, the user to send " # " signal and make circuit restoration by " # " key, put the cell phone then, and because the influence of people's custom, user's carelessness easily forgets the key by " # ", and circuit words Bi Buneng is in time restored, the normal use that influence is next, designed busy tone decoding and control circuit for this reason, realized hearing busy tone, circuit restores automatically.

IC1 is that dual-tone multifrequency receives special-purpose integrated package.Inside has clock generator, band separation filter, decoding latch circuit output.Be used for receiving the double-audio signal that remote subscriber is sent here, detect, confirm by inside, the parallel binary-coded decimal of decoding output, it is connected across the 100K that dies young on the circuit in the high resistant mode, 0.1 μ F), very little to the normal signal influence.

Off-hook button " * " that the utility model is mentioned and on-hook button " # " also can be replaced (referring to the button except that numerical key) by other key on the push-button dialling pad.

Utilize the utility model device can constitute multiple long-distance automatic or semi-automatic dial line, these are known to a person of ordinary skill in the art.Therefore will not be considered as the various usings method of the utility model device is to improvement of the present utility model.

In the physical circuit figure shown in Fig. 3 a and Fig. 3 b, the capacitor C 1 that dialing tone trap wave unit 21 receives from port 20a, the signal through normally closed contact J3-1 comes is connected to the second port 20b through a resistance R 17 then, and its resistance R 17 two ends also are connected to normal opened contact J2.Input circuit 22 comprises respectively and being connected with C2 with two capacitor C 1 that go up serial connection of the first port 20a that their correspondences are connecting capacitor C 4 and resistance R 2 and the capacitor C 3 and the resistance R 1 of series connection.Busy tone decoding unit 26 has a resistance R 23 often to open contact J3-1 to link to each other with C2 with capacitor C 1, and normally closed contact J3-2 is connected between another root lead of the capacitor C 2 and the second port 20b.A transformer L2, its one group of coil joins with forward and reverse two diode D2 in parallel and D3, and its another group coil is connected to the two ends of normal opened contact J3-2 through a resistance R 18.Dislodging machine pulse transmitting unit 31 comprises that one is connected across the normally closed contact J1 at resistance R 17 two ends, and the normal opened contact J1 that joins with normal opened contact J3-2.Double audio receiving unit 23 mainly hands over frequency receiving integrate circuit IC1 to constitute by double-tone, and its end and resistance R 2 are joined, and through 4 ends of resistance R 10 to it, 3,4 ends are respectively through resistance R 14 simultaneously, and R11 and resistance R 1 are joined; Its 7,8 termination has crystal oscillator XTAL; The series loop of being made up of capacitor C 5 and resistance R 3 is connected on 18 and 16 ends, and its mid point and 17 ends join.Decoding unit 25 has a decoding circuit IC2, its 3,4,5,6 and 7 ends respectively with 15,14,13,12 of IC1,11 ends join, simultaneously 14 and 16 ends of IC2 also connect after resistance R 5 is connected to its 9,10 ends.An inductance L 1 is connected between 1,2 end of IC2, and the two ends of inductance L 1 are connected to the negative pole of diode D3 respectively through capacitor C 1 and C8.Off-hook control unit 29 is made of drive circuit IC3, and its 4,6 is terminated at 11 ends of IC2.Pulse produces the relay J 1 of retransmission unit 28, and J2 and J3 one end and power supply 24V join, and its other end is respectively through resistance R 8, and R9 and R7 are connected to 11,10 and 12 ends of IC3.And 13 ends of IC3 are through resistance R 7, and light-emitting diode D4 separates power supply 24V.Busy tone automatic control unit 27 comprises the counting circuit IC5A and the IC5B of serial connection.3 ends of delay circuit IC12 and 1 end of IC5A join, and 7 and 6 ends join through a resistance R 22 and 2 ends of IC5A and 10 ends of IC5B, join with power supply 5V again.Power supply 5V holds also through resistance R 12, inverter ic 9F, resistance R 21, inverter ic 9E, 2 ends of capacitor C 21 to IC12.And 6 ends of IC12 and the input of IC9E are gone into the power supply pond through capacitor C 22 and C16 respectively.14 ends with 1,2 end door IC6A and IC1 hang up control unit 30 join, and it 4,5 joins with 13 ends of IC1, and it is exported 6 ends and joins through 13 ends of capacitor C 15 AND ICC8A, and goes into the power supply pond through resistance R 19.Output 13 ends of 1,2 end of IC8A and IC5B join.The output of IC8A is delivered to 7 ends of IC5A and 15 ends of IC5B through inverter ic 9B.On-hook decoding unit 24 has a counter IC7B, and 12 ends of its 9 ends and IC2 join; 10 termination power 5V; 15 ends and C9B output are joined.11,12,13 and 14 ends of IC7B join with 11,13,9 and 10 ends of IC10D and IC10C respectively, input to respectively and a door IC10B with the output of door IC10D and IC10C.Decoding unit 25 also comprises one or an IC6B, and 7 ends of its 9,10 ends and IC2 join, its 11,6 ends of 12 ends and IC2 join, and its output is connected to 1 end of trigger IC7A, the 2 termination power 5V of IC7A, the output of 7 termination IC9B, 3,4DC3 meets 4,5 of NOR gate IC8B respectively and gets, the 3 termination power ponds of IC8B, 6 ends are to 13 ends of IC2.Also have one or an IC10A, its 1 termination power ground, the output of 2 termination IC10B, 3 are connected to 7 ends of IC3.Busy tone decoding unit 26 also comprises IC circuit 4 in addition, and its 3 ends are through the negative pole of capacitor C 10 to diode D2, and 1,2 end is respectively through capacitor C 11, and C12 goes into power supply ground; 8 are connected to the input of IC9F; 7 termination power ground, string has resistance W1 and R13 between its 5,6 ends, and 5 ends are gone into power supply ground through capacitor C 13.The power supply of this device is made of 7805 common integrated circuits, and 1 termination of its IC circuit 11 has by C17, the л mode filter that R20 and C20 constitute, its 2 end ground connection, 3 ends are through capacitor C 18, and C19 goes into power supply ground, and are connected to a diode D1 between contact to 3 end of resistance R 20 and capacitor C 20.The VSS termination power ground of each integrated circuit, 9 ends of power supply 24V to IC3,3 ends of other integrated circuit (IC) 11 are for 5V voltage.

The spendable model of said integrated circuit: IC1-MT8870, IC2-MC14409, IC3-5G1413, IC4-NE567, IV5-4518, IC6-74HC21, IC7-4518, IC8-74HC27, IC9-74HC04, IC10-74HC32, IC11-7805, IC12-555.

Below all Reference numerals among Fig. 3 a and Fig. 3 b are described:

C1, C2: partiting dc capacitor R1, R2: input resistance

C3, C4: isolation capacitance R3: timing resistor

C5: fixed electric capacity R5: clamp resistance

C7, C8: oscillating capacitance R7, R8, R9: current-limiting resistance

C10: isolation coupling electric capacity R10, R11: feedback resistance

C11, C12: bypass electric capacity R12: clamp resistance

C13: demodulation electric capacity R13: demodulation resistance

C15: differential capacitance R14: feedback resistance

C16: delay capacitor R17: notch resistance

C17, C18: filter capacitor R18: current-limiting resistance

C19: decoupling capacitor R19: differential resistance

C20: filter capacitor R20: current-limiting resistance

C21: differential capacitance R21: time delay resistance

C22: timing capacitor R22: timing resistor

D1: protection diode XTAL: crystal oscillator

D2, D3: limiter diode FUSE1: protective tube

D4: luminous indicator tube

IC1: dual-tone multifrequency demodulator

J1: the control utmost point and arteries and veins IC2 are plucked in simulation: pulse generator

Relay IC3 is sent out in red switch: driver

J2: notch relay IC4:450HZ demodulator

J3: noise elimination relay ICS, IC7: counter

IC6, IC8, IC9, IC10 gate circuit

L1: vibration inductance IC11: pressurizer

L2:IC12: monostable electrical equipment

Claims (2)

1, a kind of receiving and retransmitting device of automatic continuous signal of long distance telephone call comprises first a port 20a who is connected with carrier terminal equipment two line ends, second a port 20b who is connected with local call office, and be the power supply 32 of each unit power supply, it is characterized in that:

A dialing tone trap wave unit 21 and a dislodging machine pulse transmitting unit 31 are connected in series between described first port 20a and the described second port 20b;

An input circuit unit 22 is connected across on the described first port 20a with high impedance;

A double audio receiving unit 23 is used for receiving the signal that remote subscriber sends through described input circuit unit 22, and converts double-audio signal to four binary code;

An off-hook decoding unit 25, be used to receive and translate the off-hook sign indicating number of sending from described double audio receiving unit 23, make described dislodging machine pulse transmitting unit 31 transmit the off-hook pulse signal through off-hook control unit 29 and pulse generation retransmission unit 28 again, and be that described dialing tone trap wave unit 21 inserts with high impedance during dialing tone to local call office;

Described double audio receiving unit 23 produces retransmission unit 28 with described pulse and is connected, and is used to transmit dialing signal;

An on-hook decoding unit 24, be used to receive and translate the on-hook sign indicating number of sending from described double audio receiving unit 23, through hang up control unit 30 controls, described off-hook control unit 29, pulse generation retransmission unit 28 and dislodging machine pulse transmitting unit 31 are resetted again;

A busy tone decoding unit 26, be used for receiving busy-back signal from dislodging machine pulse transmitting unit 31, make described hang up control unit 30 through busy tone automatic control unit 27 again, off-hook control unit 29, pulse produces retransmission unit 28 and dislodging machine pulse transmitting unit 31 resets.

2, receiving and retransmitting device according to claim 1 is characterized in that: described dialing tone trap wave unit 21 contains the resistor of a 20K Ω.

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