CN110809093A - Automatic adapter for wired telephone and radio station - Google Patents

Automatic adapter for wired telephone and radio station Download PDF

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Publication number
CN110809093A
CN110809093A CN201911093572.8A CN201911093572A CN110809093A CN 110809093 A CN110809093 A CN 110809093A CN 201911093572 A CN201911093572 A CN 201911093572A CN 110809093 A CN110809093 A CN 110809093A
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CN
China
Prior art keywords
circuit
detection circuit
voice
radio station
telephone
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Pending
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CN201911093572.8A
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Chinese (zh)
Inventor
倪高红
朱杰
陈�峰
许琴
钱垚
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Nanjing LES Information Technology Co. Ltd
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Nanjing LES Information Technology Co. Ltd
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Application filed by Nanjing LES Information Technology Co. Ltd filed Critical Nanjing LES Information Technology Co. Ltd
Priority to CN201911093572.8A priority Critical patent/CN110809093A/en
Publication of CN110809093A publication Critical patent/CN110809093A/en
Pending legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/005—Interface circuits for subscriber lines
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/2272—Subscriber line supervision circuits, e.g. call detection circuits
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W4/00—Services specially adapted for wireless communication networks; Facilities therefor
    • H04W4/06—Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
    • H04W4/10—Push-to-Talk [PTT] or Push-On-Call services

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Multimedia (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Telephone Function (AREA)

Abstract

The invention discloses an automatic adapter for wired telephone and radio station, comprising: a ring detection circuit, a far-end on-hook detection circuit, a communication circuit, a singlechip and a voice endpoint detection circuit; the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are respectively connected to a telephone line of the SPC exchange, and the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are hung on the telephone line as a terminal device; the program controlled exchanger distributes terminal number for the terminal device; the invention simplifies the operation of dispatching and switching the telephone and the radio station, and communication operators can immediately use the telephone to communicate with the radio station by only dialing the automatic adapter of the wired telephone and the radio station and hearing the ring back tone for three times.

Description

Automatic adapter for wired telephone and radio station
Technical Field
The invention belongs to the technical field of communication engineering, and particularly relates to an automatic adapter for a wired telephone and a radio station.
Background
The voice switching between the radio station and the wired telephone is widely applied to voice scheduling of harbor wharfs, SSBRT (service provisioning for broadcasting) services of coastal radio stations, voice scheduling of emergency command communication and the like.
When a ship sailing on the sea needs to be in contact with the land, calling a nearby coast radio station, manually switching by the coast radio station, and connecting a shipway to a telephone switching network to realize interconnection and intercommunication between the shipway and a land wired telephone;
the emergency communication commander realizes interconnection of the telephone and the short wave, interconnection of the telephone and the ultrashort wave and interconnection of the short wave and the ultrashort wave through the voice dispatching desk.
At present, voice switching between a wired telephone and a radio station is realized through a voice dispatching desk, manual operation is needed, an operator is needed to watch, and automation of the voice switching is not realized.
Disclosure of Invention
In view of the above-mentioned deficiencies of the prior art, an object of the present invention is to provide an automatic adapter for a wired telephone and a wireless station, so as to solve the problem in the prior art that voice switching between the wired telephone and the wireless station requires manual operation.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
the invention relates to an automatic adapter for a wired telephone and a radio station, which comprises: a ring detection circuit, a far-end on-hook detection circuit, a communication circuit, a singlechip and a voice endpoint detection circuit; the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are respectively connected to a telephone line of the SPC exchange, and the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are hung on the telephone line as a terminal device; the program controlled exchanger distributes terminal number for the terminal device;
the ringing detection circuit is used for converting a received ringing alternating current signal sent by the stored program controlled switch into a square wave signal and inputting the square wave signal to the singlechip as a first external interrupt signal, the singlechip switches and connects a telephone line to the call circuit, and the call circuit realizes the functions of: the voice of the remote telephone is connected to the voice detection circuit; simultaneously, the voice received by the radio station is sent to a telephone line;
the voice endpoint detection circuit is used for detecting the time endpoints of the beginning and the ending of the far-end voice of the telephone line, when the voice comes, the key control PTT signal is pulled down, the power amplifier of the radio station is opened, and the voice signal is emitted from the radio station; when the voice is over, the key control PTT signal is pulled up, the radio station power amplifier is closed, and the radio station is in an on-duty state;
the remote on-hook detection circuit is used for converting the received on-hook busy tone alternating current signal sent by the program controlled switch into a square wave signal and inputting the square wave signal to the single chip microcomputer as a second external interrupt signal, and the single chip microcomputer switches and connects the telephone line to the ringing detection circuit to realize automatic cut-off of the call circuit.
Furthermore, the ringing detection circuit is composed of a blocking filter circuit, a full-bridge rectification circuit, a voltage-stabilizing filter circuit and an optical coupling isolation circuit.
When the stored program controlled exchanger sends an alternating current signal, the direct current is isolated, the alternating current ringing signal is changed into pulsating direct current voltage after passing through a coupling capacitor CBB1, a full bridge rectifier (D5, D6, D7 and D8) and a filter electrolytic capacitor C10, and the voltage is stabilized to 15V through a voltage stabilizing diode DZ 2; then the first external interrupt signal is output to the singlechip through a photoelectric coupler OP1, a triode Q1 and a network node P3.2; the ringing signal is a sine wave of 25Hz for 1 second, and the break is held for 4 seconds, so the square wave output from P3.2 sets the first external interrupt signal of the singlechip as falling edge trigger, controls the switch S1, switches the external line of the telephone to the talking circuit after three times of ringing or four times of ringing, realizes automatic switching, and the wired telephone can talk with the radio station directly.
Further, the remote on-hook detector circuit is implemented by an integrated circuit MT 8880.
When the call is over and the remote telephone is on hook, the SPC exchange sends out busy tone signals from the line, usually 25Hz, which last 0.35 second, and then holds the busy tone of teasel root for 0.35 second; busy tone signals are received from a line through the coupling of the capacitor C15, the busy tone signals are demodulated through the integrated circuit MT8880, square wave signals are output from a pin 13 of the integrated circuit MT8880, the integrated circuit MT8880 uses a 5V power supply which is the same as that of a single chip microcomputer, square waves sent out from the pin 13 do not need optical coupling isolation, and the square wave signals can be directly connected to an external interrupt P3.3 (namely second external interrupt signals) of the single chip microcomputer.
The second external interrupt signal of the singlechip is set as falling edge trigger, the change-over switch S1 is controlled, after three times of busy tone or four times of busy tone, the external line of the telephone is switched to the ringing detection circuit, automatic on-hook is realized, the adapter is in an on-duty state, and the call of other terminals is waited.
Further, the call circuit is implemented by an integrated circuit TEA 1062A.
SCM controlled switch S1 contact (1, 2) closed, automatic adapter for wired telephone and radio station
Switching to a call state; the audio signal received from the station is inputted from pins 6 and 7 of the integrated circuit TEA1062A, amplified internally, and after the side tone is removed by the wheatstone bridge, it is outputted from pin 1 of the integrated circuit TEA1062A to the line, and the telephone at the far end can receive the voice of the station.
Voice from a remote telephone is coupled through capacitor C5, input from pin 10 of the integrated circuit TEA1062A, internally amplified, output from integrated circuit pin 4, coupled through electrolytic capacitor C2, and output to the voice endpoint detection circuit.
Further, the voice endpoint detection circuit is composed of an integrated circuit TLV320AIC23B and a processor TMS320F 28335; the voice output from pin 4 of the integrated circuit TEA1062A enters the integrated circuit TLV320AIC23B, is subjected to 16-bit analog-to-digital conversion, and is input to the processor for operation.
The voice endpoint detection circuit detects the endpoint of the voice signal of the call circuit, namely the time endpoint of the beginning and the ending of a sentence; when a voice signal exists on a circuit, a PTT signal line of a radio station is pulled down, a radio station power amplifier is enabled, and the radio station transmits; when no voice signal exists on the circuit, the PTT signal line of the radio station is pulled up, the power amplifier of the radio station is closed, and the radio station is in an on-duty state;
analog audio signals output by the talking circuit, a TI company special voice integrated circuit TLV320AIC23B accessed to the voice endpoint detection circuit, the voice integrated circuit is matched with a TMS320F28 series digital signal processor of TI company,is a 16-bit A/D, D/A converter supporting voice oversampling technology and with built-in digital filter and I2C interface, SPI interface and multichannel buffering interface.
The working mode of the integrated circuit TLV320AIC23B, the sampling rate of the voice signal is set by the SPI bus; the multi-channel buffer interface is a voice data transmission interface, and the integrated circuit TLV320AIC23B converts the voice analog from the call circuit and transmits the voice analog to digital converted voice analog to the processor data storage area through the channel. After digital operation, the key control PTT signal is generated, and the digital voice is sent to the radio station after D/A conversion.
Judging a voice endpoint by using a short-time energy method, and judging that the voice comes when the energy is greater than a set value; if the value is less than the above value, it is determined that the speech is terminated.
The invention has the beneficial effects that:
the invention simplifies the operation of dispatching and switching the telephone and the radio station, and communication operators can immediately use the telephone to communicate with the radio station by only dialing the automatic adapter of the wired telephone and the radio station and hearing the ring back tone for three times.
Drawings
Fig. 1 is a schematic diagram of the structure of the present invention.
FIG. 2 is a schematic diagram of a ringing detection circuit.
Fig. 3 is a waveform diagram of the output of the ringing detection circuit P3.2.
FIG. 4 is a circuit diagram of a remote on-hook detector.
Fig. 5 is a schematic diagram of a call circuit.
FIG. 6 is a schematic diagram of a voice endpoint detection circuit.
Detailed Description
In order to facilitate understanding of those skilled in the art, the present invention will be further described with reference to the following examples and drawings, which are not intended to limit the present invention.
Referring to fig. 1, an automatic adapter for wired telephone and radio station according to the present invention comprises: a ring detection circuit, a far-end on-hook detection circuit, a communication circuit, a singlechip and a voice endpoint detection circuit; the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are respectively connected to a telephone line of the SPC exchange, and the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are hung on the telephone line as a terminal device; the program controlled exchanger distributes terminal number for the terminal device;
the ringing detection circuit is used for converting a received ringing alternating current signal sent by the stored program controlled switch into a square wave signal and inputting the square wave signal to the singlechip as a first external interrupt signal, the singlechip switches and connects a telephone line to the call circuit, and the call circuit realizes the functions of: the voice of the remote telephone is connected to the voice detection circuit; and simultaneously, the voice received by the radio station is sent to the telephone line.
The voice endpoint detection circuit is used for detecting the time endpoints of the beginning and the ending of the far-end voice of the telephone line, when the voice comes, the key control PTT signal is pulled down, the power amplifier of the radio station is opened, and the voice signal is emitted from the radio station; when the voice is over, the key control PTT signal is pulled up, the radio station power amplifier is closed, and the radio station is in an on-duty state;
the remote on-hook detection circuit is used for converting the received on-hook busy tone alternating current signal sent by the program controlled switch into a square wave signal and inputting the square wave signal to the single chip microcomputer as a second external interrupt signal, and the single chip microcomputer switches and connects the telephone line to the ringing detection circuit to realize automatic cut-off of the call circuit.
The ringing detection circuit is composed of a blocking filter circuit, a full-bridge rectification circuit, a voltage-stabilizing filter circuit and an optical coupling isolation circuit.
Referring to fig. 2, when the program controlled exchange sends an ac signal, the dc is isolated, and the ac ringing signal is converted into pulsating dc voltage through the coupling capacitor CBB1, the full bridge rectifier (D5, D6, D7, D8) and the filtering electrolytic capacitor C10, and is regulated to 15V through the zener diode DZ 2; then the first external interrupt signal is output to the singlechip through a photoelectric coupler OP1, a triode Q1 and a network node P3.2; the ringing signal is typically a positive spin of 25Hz on for 1 second followed by a chop for 4 seconds, so the square wave output from P3.2 is as in fig. 3: the first external interrupt signal of the single chip computer is set as falling edge trigger, the change-over switch S1 is controlled, after three times of ringing or four times of ringing, the external line of the telephone is switched to the talking circuit, automatic switching is realized, and the wired telephone can directly talk with the radio station.
The far-end on-hook detection circuit is realized by an integrated circuit MT 8880.
Referring to fig. 4, when the call is over and the remote telephone is on hook, the SPC exchange sends a busy tone signal from the line, usually 25Hz, a positive spin wave that lasts for 0.35 seconds, followed by a busy tone for 0.35 seconds holding a teasel; busy tone signals are received from a line through the coupling of the capacitor C15, the busy tone signals are demodulated through the integrated circuit MT8880, square wave signals are output from a pin 13 of the integrated circuit MT8880, the integrated circuit MT8880 uses a 5V power supply which is the same as that of a single chip microcomputer, square waves sent out from the pin 13 do not need optical coupling isolation, and the square wave signals can be directly connected to an external interrupt P3.3 (namely second external interrupt signals) of the single chip microcomputer.
The second external interrupt signal of the singlechip is set as falling edge trigger, the change-over switch S1 is controlled, after three times of busy tone or four times of busy tone, the external line of the telephone is switched to the ringing detection circuit, automatic on-hook is realized, the adapter is in an on-duty state, and the call of other terminals is waited.
Referring to fig. 5, the call circuit is implemented by an integrated circuit TEA 1062A.
SCM controlled switch S1 contact (1, 2) closed, automatic adapter for wired telephone and radio station
Switching to a call state; the audio signal received from the station is inputted from pins 6 and 7 of the integrated circuit TEA1062A, amplified internally, and after the side tone is removed by the wheatstone bridge, it is outputted from pin 1 of the integrated circuit TEA1062A to the line, and the telephone at the far end can receive the voice of the station.
Voice from a remote telephone is coupled through capacitor C5, input from pin 10 of the integrated circuit TEA1062A, internally amplified, output from integrated circuit pin 4, coupled through electrolytic capacitor C2, and output to the voice endpoint detection circuit.
Referring to fig. 6, the voice endpoint detection circuit is composed of an integrated circuit TLV320AIC23B and a processor TMS320F 28335; the voice output from pin 4 of the integrated circuit TEA1062A enters the integrated circuit TLV320AIC23B, is subjected to 16-bit analog-to-digital conversion, and is input to the processor for operation.
The voice endpoint detection circuit detects the endpoint of the voice signal of the call circuit, namely the time endpoint of the beginning and the ending of a sentence; when a voice signal exists on a circuit, a PTT signal line of a radio station is pulled down, a radio station power amplifier is enabled, and the radio station transmits; when no voice signal exists on the circuit, the PTT signal line of the radio station is pulled up, the power amplifier of the radio station is closed, and the radio station is in an on-duty state;
analog audio signals output by a talking circuit, a TI company special voice integrated circuit TLV320AIC23B accessed to a voice endpoint detection circuit, the voice integrated circuit is matched with a TMS320F28 series digital signal processor of TI company, is a 16-bit A/D, D/A converter, supports voice oversampling technology, is internally provided with a digital filter, and is provided with an I/D, D/A converter2C interface, SPI interface and multichannel buffering interface.
The working mode of the integrated circuit TLV320AIC23B, the sampling rate of the voice signal is set by the SPI bus; the multi-channel buffer interface is a voice data transmission interface, and the integrated circuit TLV320AIC23B converts the voice analog from the call circuit and transmits the voice analog to digital converted voice analog to the processor data storage area through the channel. After digital operation, the key control PTT signal is generated, and the digital voice is sent to the radio station after D/A conversion.
Judging a voice endpoint by using a short-time energy method, and judging that the voice comes when the energy is greater than a set value; if the value is less than the above value, it is determined that the speech is terminated.
The telephone dial wired telephone and radio station automatic adapter, the adapter rings and picks up automatically, the telephone is connected with the adapter through PSTN network pronunciation, the pronunciation of the telephone is transmitted to radio station B through the adapter, control radio station B to transmit at the same time, the radio station A has received the pronunciation of the telephone.
On the other hand, the radio station A calls the radio station B, the voice received by the radio station B is sent to the PSTN bearer network through the adapter, and finally the telephone is heard by the voice of the radio station A.
When the call is completed and the telephone is on-hook, the adapter must automatically detect the on-hook signal, so as to realize that the adapter follows the telephone to automatically on-hook and is in an on-duty state, so as to receive the next dialing of other telephones.
While the invention has been described in terms of its preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims (5)

1. An automatic wire telephone to radio adapter comprising: a ring detection circuit, a far-end on-hook detection circuit, a communication circuit, a singlechip and a voice endpoint detection circuit; the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are respectively connected to a telephone line of the SPC exchange, and the ringing detection circuit, the far-end on-hook detection circuit and the talking circuit are hung on the telephone line as a terminal device; the program controlled exchanger distributes terminal number for the terminal device;
the ringing detection circuit is used for converting a received ringing alternating current signal sent by the stored program controlled switch into a square wave signal and inputting the square wave signal to the singlechip as a first external interrupt signal, and the singlechip switches and connects a telephone line to the call circuit;
the voice endpoint detection circuit is used for detecting the time endpoints of the beginning and the ending of the far-end voice of the telephone line, when the voice comes, the key control PTT signal is pulled down, the power amplifier of the radio station is opened, and the voice signal is emitted from the radio station; when the voice is over, the key control PTT signal is pulled up, the radio station power amplifier is closed, and the radio station is in an on-duty state;
the remote on-hook detection circuit is used for converting the received on-hook busy tone alternating current signal sent by the program controlled switch into a square wave signal and inputting the square wave signal to the single chip microcomputer as a second external interrupt signal, and the single chip microcomputer switches and connects the telephone line to the ringing detection circuit to realize automatic cut-off of the call circuit.
2. The automatic adapter of claim 1, wherein said ringing detection circuit comprises a dc blocking filter circuit, a full bridge rectifier circuit, a voltage stabilizing filter circuit and an optical coupling isolation circuit.
3. The automatic wired telephone to radio switch according to claim 1, wherein said remote on-hook detector circuit is implemented by an integrated circuit MT 8880.
4. The automatic wired telephone to radio adapter of claim 1, wherein said telephony circuit is implemented by an integrated circuit TEA 1062A.
5. The automatic wired telephone and radio station switch according to claim 1, wherein said voice endpoint detection circuit is comprised of an integrated circuit TLV320AIC23B and a processor TMS320F 28335; the voice output from pin 4 of the integrated circuit TEA1062A enters the integrated circuit TLV320AIC23B, is subjected to 16-bit analog-to-digital conversion, and is input to the processor for operation.
CN201911093572.8A 2019-11-11 2019-11-11 Automatic adapter for wired telephone and radio station Pending CN110809093A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113452856A (en) * 2021-08-30 2021-09-28 交通运输部规划研究院 Automatic wired and wireless voice switching device and conversation method thereof

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2914512Y (en) * 2006-05-25 2007-06-20 叶志刚 Wired or wireless accepting or refusing device for letting interphone make a call
CN102626000A (en) * 2009-07-06 2012-08-01 泰帝公司 Two-way radio based unified communications system
CN104010099A (en) * 2014-05-07 2014-08-27 中国人民解放军63892部队 Method and device for communicating telephone system and talkback dispatching system
CN105356927A (en) * 2015-12-25 2016-02-24 河南省电力勘测设计院 Relay method and relay adaptor for short-wave radio station
CN105684405A (en) * 2013-11-07 2016-06-15 艾可慕株式会社 Relay device, voice communication system, program, and method for relaying voice signal

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2914512Y (en) * 2006-05-25 2007-06-20 叶志刚 Wired or wireless accepting or refusing device for letting interphone make a call
CN102626000A (en) * 2009-07-06 2012-08-01 泰帝公司 Two-way radio based unified communications system
CN105684405A (en) * 2013-11-07 2016-06-15 艾可慕株式会社 Relay device, voice communication system, program, and method for relaying voice signal
CN104010099A (en) * 2014-05-07 2014-08-27 中国人民解放军63892部队 Method and device for communicating telephone system and talkback dispatching system
CN105356927A (en) * 2015-12-25 2016-02-24 河南省电力勘测设计院 Relay method and relay adaptor for short-wave radio station

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113452856A (en) * 2021-08-30 2021-09-28 交通运输部规划研究院 Automatic wired and wireless voice switching device and conversation method thereof

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