CN112751979A - DTMF encoding method, DTMF decoding method, DTMF encoder, DTMF decoder, and communication apparatus - Google Patents
DTMF encoding method, DTMF decoding method, DTMF encoder, DTMF decoder, and communication apparatus Download PDFInfo
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M7/00—Arrangements for interconnection between switching centres
- H04M7/12—Arrangements for interconnection between switching centres for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal
- H04M7/1205—Arrangements for interconnection between switching centres for working between exchanges having different types of switching equipment, e.g. power-driven and step by step or decimal and non-decimal where the types of switching equipement comprises PSTN/ISDN equipment and switching equipment of networks other than PSTN/ISDN, e.g. Internet Protocol networks
- H04M7/1295—Details of dual tone multiple frequency signalling
Abstract
The invention discloses a DTMF coding and decoding method, a coder, a decoder and a communication device. The DTMF coding method comprises the following steps: acquiring digital information to be sent; converting the digital information to be transmitted into a frequency signal; generating a preset high-frequency signal; superposing the frequency signal and the high-frequency signal to form a target transmitting signal; and transmitting the target transmission signal. By mixing the high-frequency anti-interference signal into the DTMF frequency signal to be transmitted, the probability of the DTMF being interfered in the transmission process is greatly reduced, and the situations of false alarm and false alarm caused by the interference of the signal are effectively reduced.
Description
Technical Field
The present invention relates to the field of Dual Tone Multi-Frequency communication technology, and in particular, to a Dual Tone Multi-Frequency (DTMF) encoding and decoding method, an encoder, a decoder, and a communication device.
Background
DTMF is a method of representing digits by tones in a voice channel, and can be used to transmit signaling in an analog voice channel, and thus has a wide application in the field of communications. The DTMF is composed of high-frequency groups and low-frequency groups, wherein each high-frequency group and each low-frequency group comprises 4 frequencies, and a high-frequency signal and a low-frequency signal are superposed to form a combined signal which represents a digit.
In the popularization process of the internet of things, communication equipment is not limited to communication equipment such as mobile phones, more and more equipment support the voice communication function, daily equipment such as vending machines, automobiles and elevators can be connected to the internet of things and can carry out voice communication with users. The frequency points of the DTMF are all within the range of 600Hz (hertz) -1700 Hz, which is the frequency range most frequently used in voice communication, so that with the popularization of the internet of things, the probability of the interference of the conventional DTMF in the encoding and decoding processes is relatively high. When DTMF is transmitted by voice, common false alarm types include false alarm, missed alarm and multiple alarm. Wherein, when the interference frequency falls in the high frequency group and the low frequency group of DTMF, it will cause the false report or the multiple reports.
Disclosure of Invention
The invention provides a DTMF coding and decoding method, an encoder, a decoder and a communication device, aiming at overcoming the defects that false reports and multiple reports are easy to occur in the transmission process of DTMF in the prior art.
The invention solves the technical problems through the following technical scheme:
the invention provides a DTMF coding method, which comprises the following steps:
acquiring digital information to be sent;
converting the digital information to be transmitted into a frequency signal;
generating a preset high-frequency signal;
superposing the frequency signal and the high-frequency signal to form a target transmitting signal;
and transmitting the target transmission signal.
Preferably, the frequency of the preset high-frequency signal is greater than or equal to 10 KHz.
Preferably, after the step of superimposing the frequency signal and the high-frequency signal to form a target transmission signal, the DTMF encoding method further includes:
converting the target transmission signal from a digital signal to an analog signal.
The invention also provides a DTMF decoding method, which comprises the following steps:
receiving a signal to be decoded and transmitted;
detecting whether the to-be-decoded transmission signal comprises a preset high-frequency signal or not;
if so, decoding the to-be-decoded sending signal to obtain target digital information, and outputting the target digital information; if not, outputting the abnormity of the signal to be decoded and sent.
Preferably, after the step of receiving the transmission signal to be decoded, the DTMF decoding method further includes:
and converting the to-be-decoded transmission signal from an analog signal to a digital signal.
The invention also provides a DTMF encoder which comprises an input module, an encoding module and a sending module; the coding module comprises a high-frequency anti-interference unit;
the input module is used for acquiring digital information to be sent;
the coding module is used for converting the digital information to be sent into a frequency signal;
the high-frequency anti-interference unit is used for generating a preset high-frequency signal;
the coding module is further used for superposing the frequency signal and the high-frequency signal to form a target sending signal;
the sending module is used for sending the target sending signal.
Preferably, the frequency of the preset high-frequency signal is greater than or equal to 10 KHz.
Preferably, the DTMF encoder further comprises a digital-to-analog conversion module;
the digital-to-analog conversion module is used for converting the target sending signal from a digital signal to an analog signal.
The invention also provides a DTMF decoder, which comprises a receiving module, a decoding module and an output module; the decoding module comprises a start bit detection unit, a decoding unit and an exception handling unit;
the receiving module is used for receiving a signal to be decoded and sent;
the start bit detection unit is used for detecting whether the signal to be decoded comprises a preset high-frequency signal or not, if so, the decoding unit is called, and if not, the exception handling unit is called;
the decoding unit is used for decoding the to-be-decoded sending signal to obtain target digital information and calling the output module;
the exception handling unit is used for outputting the exception of the signal to be decoded and sent.
The output module is used for outputting the target digital information.
Preferably, the DTMF decoder further comprises an analog-to-digital conversion module;
the analog-to-digital conversion module is used for converting the to-be-decoded sending signal from an analog signal to a digital signal.
The invention also provides a DTMF communication device, which comprises the DTMF encoder and the DTMF decoder, wherein the DTMF encoder and the DTMF decoder are respectively used for receiving the DTMF signal;
the DTMF encoder is used for sending the target sending signal to the DTMF decoder;
and the DTMF decoder is used for receiving the target sending signal to acquire the sending signal to be decoded.
The positive progress effects of the invention are as follows:
by mixing the high-frequency anti-interference signal into the DTMF frequency signal to be transmitted, the probability of the DTMF being interfered in the transmission process is greatly reduced, and the situations of false alarm and false alarm caused by the interference of the signal are effectively reduced.
Drawings
Fig. 1 is a flowchart of a DTMF coding method according to embodiment 1 of the present invention.
Fig. 2 is a conventional DTMF encoding of the character "6" of the prior art.
Fig. 3 is a DTMF code obtained by the DTMF coding method of embodiment 1 for the character "6".
Fig. 4 is a flowchart of a DTMF decoding method according to embodiment 2 of the present invention.
Fig. 5 is a block diagram of a DTMF encoder according to embodiment 4 of the present invention.
Fig. 6 is a block diagram of a DTMF decoder according to embodiment 5 of the present invention.
Fig. 7 is a block diagram of a DTMF communication apparatus according to embodiment 6 of the present invention.
Detailed Description
The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention.
Example 1
As shown in fig. 1, the present embodiment provides a DTMF encoding method, which includes:
s101, acquiring digital information to be transmitted;
s102, converting digital information to be transmitted into a frequency signal;
s103, generating a preset high-frequency signal;
s104, superposing the frequency signal and the high-frequency signal to form a target sending signal;
s105, converting the target transmission signal from a digital signal to an analog signal;
and S106, transmitting the target transmission signal.
Specifically, the frequency of the preset high-frequency signal is greater than or equal to 10 KHz.
It is known in the art that DTMF can lock one character only by two frequency points in the encoding and decoding processes, the mode is simple, the efficiency is high, and as shown in fig. 2, the character "6" is locked by 770Hz and 1477 Hz. When DTMF is transmitted through voice, the frequency of an interference signal is generally less than 10KHz, and particularly, the probability of being interfered is very high within the frequency point range of 600Hz to 1700 Hz. Whereas in the frequency range above 10KHz the probability of being disturbed is very small. As shown in fig. 3, based on the DTMF encoding method of the present embodiment, the frequency signal of the character "6" contains three frequency components of 770Hz, 1477Hz, and 10 KHz. Interference signals larger than or equal to 10KHz are mixed in the sending signals in the coding process, so that the probability of interference of DTMF in the transmission process can be effectively reduced.
According to the DTMF coding method, the high-frequency anti-interference signal is mixed in the frequency signal to be sent, so that the probability of the DTMF being interfered in the transmission process is greatly reduced, and the situations of false alarm and false alarm caused by the interference of the signal are effectively reduced.
Example 2
As shown in fig. 4, the present embodiment provides a DTMF decoding method, which includes:
s201, receiving a signal to be decoded and sent;
s202, converting a to-be-decoded sending signal from an analog signal into a digital signal;
s203, detecting whether the to-be-decoded transmission signal comprises a preset high-frequency signal, if so, executing a step S204, and if not, executing a step S205;
s204, decoding the to-be-decoded sending signal to obtain target digital information, and outputting the target digital information; the flow ends.
And S205, outputting the exception of the to-be-decoded transmission signal to remind further processing, wherein for example, decoding of the to-be-decoded transmission signal can be abandoned.
The DTMF coding method of this embodiment detects whether the frequency signal is mixed with the high-frequency anti-interference signal, and decodes the frequency signal only when the frequency signal includes the high-frequency anti-interference signal, and effectively reduces the situations of false alarm and false alarm caused by the interference of the signal by increasing the high-frequency anti-interference signal.
Example 3
This embodiment provides a DTMF communication method, which encodes digital information by using the DTMF encoding method in embodiment 1 to obtain a transmission signal, and then decodes the transmission signal by using the DTMF decoding method in embodiment 2 to obtain the digital information.
In the DTMF communication method of this embodiment, by mixing a high-frequency interference-preventing signal into a frequency signal to be transmitted, the probability of the DTMF being interfered during transmission is greatly reduced; when receiving signals, whether the frequency signals are mixed with the high-frequency anti-interference signals or not is detected, and the frequency signals are decoded only when the frequency signals comprise the high-frequency anti-interference signals, so that the situations of false alarm and false alarm caused by the interference of the signals are effectively reduced.
Example 4
As shown in fig. 5, the present embodiment provides a DTMF encoder, which includes an input module 11, an encoding module 12, a sending module 13, and a digital-to-analog conversion module 14; the encoding module 12 includes a high frequency interference preventing unit 121.
The input module 11 is used for acquiring digital information to be sent;
the encoding module 12 is configured to convert digital information to be transmitted into a frequency signal;
the high-frequency interference preventing unit 121 is configured to generate a preset high-frequency signal;
the encoding module 12 is further configured to superimpose the frequency signal and the high-frequency signal to form a target transmission signal;
the transmitting module 13 is configured to transmit a target transmission signal.
The digital-to-analog conversion module 14 is used for converting the target transmission signal from a digital signal to an analog signal.
It is known in the art that DTMF can lock one character only by two frequency points in the encoding and decoding processes, the mode is simple, the efficiency is high, and as shown in fig. 2, the character "6" is locked by 770Hz and 1477 Hz. When DTMF is transmitted through voice, the frequency of an interference signal is generally less than 10KHz, and particularly, the probability of being interfered is very high within the frequency point range of 600Hz to 1700 Hz. Whereas in the frequency range above 10KHz the probability of being disturbed is very small. As shown in fig. 3, based on the DTMF encoding method of the present embodiment, the frequency signal of the character "6" contains three frequency components of 770Hz, 1477Hz, and 10 KHz. Interference signals larger than or equal to 10KHz are mixed in the sending signals in the coding process, so that the probability of interference of DTMF in the transmission process can be effectively reduced.
The DTMF encoder of the embodiment enables the probability of DTMF interference in the transmission process to be greatly reduced by mixing the high-frequency anti-interference signal into the frequency signal to be transmitted, and effectively reduces the situations of false alarm and false alarm caused by the interference of the signal.
Example 5
As shown in fig. 6, the present embodiment provides a DTMF decoder, which includes a receiving module 21, a decoding module 22, an output module 23, and an analog-to-digital conversion module 24; the decoding module 22 includes a start bit detection unit 221, a decoding unit 222, and an exception handling unit 223.
The receiving module 21 is configured to receive a to-be-decoded transmission signal;
the start bit detection unit 221 is configured to detect whether the to-be-decoded transmission signal includes a preset high-frequency signal, if so, invoke the decoding unit 222, and if not, invoke the exception handling unit 223;
the decoding unit 222 is configured to decode the transmission signal to be decoded to obtain target digital information, and call the output module 23;
the exception handling unit 223 is configured to output an exception to the to-be-decoded transmission signal to prompt further processing or directly process, for example, decoding of the to-be-decoded transmission signal may be abandoned.
The output module 23 is used for outputting the target digital information;
the analog-to-digital conversion module 24 is used for converting the transmission signal to be decoded from an analog signal into a digital signal.
The DTMF coding method of this embodiment detects whether the frequency signal is mixed with the high-frequency anti-interference signal, and decodes the frequency signal only when the frequency signal includes the high-frequency anti-interference signal.
Example 6
As shown in fig. 7, the present embodiment provides a DTMF communication apparatus including a DTMF encoder 31 of embodiment 4 and a DTMF decoder 32 of embodiment 5.
The DTMF encoder is used for sending a target sending signal to the DTMF decoder;
the DTMF decoder is used for receiving the target sending signal to acquire a sending signal to be decoded.
In the DTMF communication device of this embodiment, by mixing a high-frequency interference-preventing signal into a frequency signal to be transmitted, the probability of the DTMF being interfered during transmission is greatly reduced; when receiving signals, whether the frequency signals are mixed with the high-frequency anti-interference signals or not is detected, and the frequency signals are decoded only when the frequency signals comprise the high-frequency anti-interference signals, so that the situations of false alarm and false alarm caused by the interference of the signals are effectively reduced.
While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and that the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are within the scope of the invention.
Claims (11)
1. A DTMF encoding method, comprising:
acquiring digital information to be sent;
converting the digital information to be transmitted into a frequency signal;
generating a preset high-frequency signal;
superposing the frequency signal and the high-frequency signal to form a target transmitting signal;
and transmitting the target transmission signal.
2. The DTMF coding method of claim 1, wherein the frequency of the predetermined high frequency signal is greater than or equal to 10 KHz.
3. The DTMF encoding method of claim 1, wherein after said step of superimposing said frequency signal and said high frequency signal into a target transmission signal, said DTMF encoding method further comprises:
converting the target transmission signal from a digital signal to an analog signal.
4. A DTMF decoding method, comprising:
receiving a signal to be decoded and transmitted;
detecting whether the to-be-decoded transmission signal comprises a preset high-frequency signal or not;
if so, decoding the to-be-decoded sending signal to obtain target digital information, and outputting the target digital information; if not, outputting the abnormity of the signal to be decoded and sent.
5. The DTMF decoding method of claim 4, wherein after the step of receiving a transmission signal to be decoded, the DTMF decoding method further comprises:
and converting the to-be-decoded transmission signal from an analog signal to a digital signal.
6. A DTMF encoder comprising an input module, an encoding module and a sending module; the coding module comprises a high-frequency anti-interference unit;
the input module is used for acquiring digital information to be sent;
the coding module is used for converting the digital information to be sent into a frequency signal;
the high-frequency anti-interference unit is used for generating a preset high-frequency signal;
the coding module is further used for superposing the frequency signal and the high-frequency signal to form a target sending signal;
the sending module is used for sending the target sending signal.
7. The DTMF encoder of claim 6, wherein said predetermined high frequency signal has a frequency of 10KHz or more.
8. The DTMF encoder of claim 6, wherein said DTMF encoder further comprises a digital-to-analog conversion module;
the digital-to-analog conversion module is used for converting the target sending signal from a digital signal to an analog signal.
9. A DTMF decoder comprising a receiving module, a decoding module and an output module; the decoding module comprises a start bit detection unit, a decoding unit and an exception handling unit;
the receiving module is used for receiving a signal to be decoded and sent;
the start bit detection unit is used for detecting whether the signal to be decoded comprises a preset high-frequency signal or not, if so, the decoding unit is called, and if not, the exception handling unit is called;
the decoding unit is used for decoding the to-be-decoded sending signal to obtain target digital information and calling the output module;
the exception handling unit is used for outputting the exception of the signal to be decoded and sent;
the output module is used for outputting the target digital information.
10. The DTMF decoder of claim 9, wherein the DTMF decoder further comprises an analog-to-digital conversion module;
the analog-to-digital conversion module is used for converting the to-be-decoded sending signal from an analog signal to a digital signal.
11. A DTMF communications apparatus, characterized in that the DTMF communications apparatus comprises the DTMF encoder of any one of claims 6-8 and the DTMF decoder of any one of claims 9-10;
the DTMF encoder is used for sending a target sending signal to the DTMF decoder;
and the DTMF decoder is used for receiving the target sending signal to acquire a sending signal to be decoded.
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