CN103761972A - Short-wave communication digital voice sending and receiving device and transmission method - Google Patents
Short-wave communication digital voice sending and receiving device and transmission method Download PDFInfo
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Abstract
The invention discloses a short-wave communication digital voice sending and receiving device. In the sending process, voice frequency is sent to a control processing module and sent to a vocoder to code after passing through an A/D module, the coded digital voice frequency is sent to a data sending module and sent in the ARQ data transmission mode; data coded by the vocoder are sent to a voice management module through an SPI to be stored and stored data, coded by the vocoder, of sent voice can be called out and sent to a voice frequency receiving device to be replayed; in the receiving process, one path of data to be decoded which are received by a data receiving module are sent to the voice management module through an SPI module to be stored, the other path of data are restored to analog voice frequency through a voice frequency D/A module after being decoded by the vocoder and sent to the voice frequency receiving device, and stored data to be decoded of received voice can be called out and sent to the voice frequency receiving device to be replayed. The invention further discloses a transmission method of short-wave communication digital voice. The problem that traditional short-wave communication digital voice is low in quality is solved and replaying control over the voice can be conducted.
Description
Technical field
The present invention relates to short wave communication field, relate in particular to a kind of short wave communication digital voice transceiver and transmission method.
Background technology
In short wave communication, signal is through after ionospheric propagation, and the random fluctuations of receiving end signal amplitude, is called " decline ".The quick random variation of signal strength is called rapid fading, only part second to tens of seconds duration.The slow random variation of signal strength is called slow fading.Duration is longer, can reach even several hours a few minutes.Cause the main cause of signal dropout to have multipath to interfere, polarization variation, ionosphere Change of absorption and Ionospheric Movement etc.
Slow fading is mainly because d-layer Change of absorption is caused.It is relevant by the variation of ionospheric electron density and height.The duration of this slow fading is not from several minutes to several hours etc.Diurnal variation, seasonal variations all belong to slow fading.Absorption fading can produce identical impact to whole shortwave frequency range.In the situation that ionosphere does not have other harassing and wrecking, dafing depth can reach the following 10dB of mean value.
Rapid fading be mainly due to polarization fading and multipath transmisstion caused.The Rayleigh distributed that the amplitude of rapid fading signal has, some obeys logarithm normal distribution.As mentioned before, because ionosphere presents vertical stratification characteristic, and ionospheric density and height random variation, causes the signal that arrives receiving end through different travel paths can not keep stable phase differential, and unsettled phase differential can cause the rapid fading of signal amplitude.This decline is mainly because the interference of different path signals causes, and therefore, is generally also called " interference fading ".Interference fading has obvious frequency selectivity.And because the root mean square time delay expansion of short wave channel is generally larger, therefore correlated bandwidth is less.From the shorter observation cycle, the amplitude fading Rayleigh distributed of signal.When carrying out short wave channel emulation, it is generally acknowledged that channel is rayleigh fading channel.During signal dropout, signal strength changes up to 30dB, sometimes can reach 60～80dBtll.During decline, receiving end signal-to-noise ratio degradation, error rate of system raises, and to short wave communication, brings very large impact.
Also there is polarization fading in short wave channel.Because disturb terrestrial magnetic field, through the plane polarized wave of ionospheric propagation, can be split into two elliptically polarised waves.When ionospheric electron density random fluctuation, the principal axis of ellipse direction of each elliptically polarised wave is also with change, and the induced potential on receiving antenna produces random fluctuation.Polarization fading also belongs to rapid fading.Generally account for 10%～15% left and right of whole declines.
Just because of short wave channel, it is a multidiameter fading channel, have and become dispersivity when serious, in order to reduce the requirement to signal to noise ratio (S/N ratio), in short wave communication, the low code rate acoustic code words of the general 600bps of employing are communicated by letter, but the speech quality of low rate acoustic code words is unsatisfactory all the time.
Summary of the invention
In order to overcome the deficiencies in the prior art, the invention provides a kind of short wave communication digital voice transceiver and transmission method, to solve traditional short wave communication digital voice problem of low quality, also can carry out the playback controls of speech.
For achieving the above object, the present invention takes following technical scheme:
A kind of short wave communication digital voice dispensing device, this device comprises audio frequency transmitting apparatus, controls processing module, voice management module and audio reception device; Described control processing module comprises audio A/D module, acoustic code scrambler, data transmission blocks, acoustic code demoder, SPI interface module and audio frequency D/A module;
Described audio frequency transmitting apparatus sends audio A/D module by audio analog signals, described audio A/D module is carried out after analog to digital conversion the audio analog signals of accepting, the audio digital signals of acquisition is sent to acoustic code scrambler, described acoustic code scrambler sends to data transmission blocks after the audio digital signals receiving is encoded, and sends to voice management module by SPI interface module simultaneously; Described data transmission blocks is counted biography mode by the audio digital signals after coding with ARQ and is sent; The audio digital signals of described voice management module after to the coding receiving stored, and the audio digital signals of storage is sent to acoustic code demoder by SPI interface module, described acoustic code demoder is decoded to the audio digital signals receiving, and send to audio frequency D/A module, described audio frequency D/A module is carried out digital-to-analog conversion to decoded audio digital signals, and sends to audio reception device to carry out voice reproducing the audio analog signals of acquisition.
Further, acoustic code scrambler and acoustic code demoder adopt high code rate vocoder to encode, and high code rate vocoder adopts and is greater than 600bps rate vocoder, such as 2400bps vocoder.
A kind of short wave communication digital voice receiving trap, this device comprises controls processing module, voice management module and audio reception device, and described control processing module comprises data reception module, SPI interface module, acoustic code demoder and audio frequency D/A module;
Described data reception module sends to acoustic code demoder by the audio digital signals receiving, and also by SPI interface module, sends to voice management module; Described voice management module is stored the audio digital signals receiving, and the audio digital signals of storage is sent to acoustic code demoder; Described acoustic code demoder is issued audio frequency D/A module after the audio digital signals receiving is decoded, and described audio frequency D/A module carries out decoded audio digital signals to send to audio reception device after digital-to-analog conversion.
Further, acoustic code demoder adopts two-forty vocoder to decode, and high code rate vocoder adopts and is greater than 600bps rate vocoder, such as 2400bps vocoder.
A kind of short wave communication digital voice control transmission method, comprises the steps:
Transmitting terminal:
(1) original state;
(2) judge whether to send audio analog signals, if so, jump into step (3), otherwise, jump into step (6);
(3) audio analog signals that will send is carried out to A/D sampling, and the audio digital signals that sampling is obtained carries out acoustic code coding;
(4) audio digital signals after coding is stored;
(5) audio digital signals after coding is carried out to agreement framing, the voice data after agreement framing is counted to biography mode with ARQ and send;
(6) judge whether the audio digital signals of storage to be sent, if so, the audio digital signals of storage is carried out to ARQ, count biography mode after agreement framing and send; Otherwise jump into step (7);
(7) judge whether to carry out voice reproducing to the audio digital signals of storage, if so, the audio digital signals of storage decoded, be reduced into audio analog signals after D/A conversion, be sent to audio reception device and carry out voice reproducing; Otherwise return to step (1) original state;
(8) finish;
Receiving end:
(1) original state;
(2) judgement need to be carried out voice reproducing to the audio digital signals to be decoded of storage, if so, jumps into step (6); Otherwise jump into step (3)
(3) judge whether to receive that ARQ counts the voice data that biography mode transmits, if so, jump into step (4); Otherwise return to original state;
(4) voice data receiving is resolved and obtain audio digital signals to be decoded;
(5) audio digital signals to be decoded is stored;
(6) audio digital signals to be decoded is decoded, and change and be reduced into audio analog signals by D/A, be then sent to audio reception device and carry out audio frequency broadcasting;
(7) finish.
Beneficial effect: (1) the present invention is applied to digital voice control and the transmission of short-wave radio set, owing to having adopted high code rate acoustic code, the acoustic code of the low rate adopting with traditional short wave communication is compared, and speech naturalness improves; (2) the present invention carries out digital voice transmission owing to having adopted ARQ to count biography mode, and that has improved speech can passband; (3) playback function of speech provided by the invention has promoted user's experience.
Accompanying drawing explanation
Fig. 1 is a kind of short wave communication digital voice dispensing device structural drawing provided by the invention.
Fig. 2 is a kind of short wave communication digital voice receiving trap structural drawing provided by the invention.
Fig. 3 is a kind of short wave communication digital voice sending method process flow diagram provided by the invention.
Fig. 4 is a kind of short wave communication digital voice method of reseptance process flow diagram provided by the invention.
Fig. 5 is acoustic playback provided by the invention interface.
Embodiment
Below in conjunction with accompanying drawing, the present invention is further described.
As shown in Figure 1, a kind of short wave communication digital voice dispensing device provided by the invention, this device comprises audio frequency transmitting apparatus, controls processing module, voice management module and audio reception device; Described control processing module comprises audio A/D module, acoustic code scrambler, data transmission blocks, acoustic code demoder, SPI interface module and audio frequency D/A module;
Described audio frequency transmitting apparatus sends audio A/D module by audio analog signals, described audio A/D module is carried out after analog to digital conversion the audio analog signals of accepting, the audio digital signals of acquisition is sent to acoustic code scrambler, described acoustic code scrambler sends to data transmission blocks after the audio digital signals receiving is encoded, and sends to voice management module by SPI interface module simultaneously; Described data transmission blocks is counted biography mode by the audio digital signals after coding with ARQ and is sent; The audio digital signals of described voice management module after to the coding receiving stored, and the audio digital signals of storage is sent to acoustic code demoder by SPI interface module, described acoustic code demoder is decoded to the audio digital signals receiving, and send to audio frequency D/A module, described audio frequency D/A module is carried out digital-to-analog conversion to decoded audio digital signals, and sends to audio reception device to carry out voice reproducing the audio analog signals of acquisition.
While sending speech, the audio frequency of audio frequency transmitting apparatus is delivered to control processing module by audio interface, after audio A/D, give high code rate vocoder and encode, such as 2400bps vocoder, the DAB after coding is sent to data transmission blocks and with ARQ, counts biography mode and send.Data after vocoder coding are given voice management module by SPI interface and are stored, can recall data after the transmission speech vocoder coding of storage, through acoustic code decoding, after audio frequency D/A conversion, be sent to audio reception device and carry out playback, as shown in Figure 5, left side horizontal stripe is the indication that sends speech at the interface of acoustic playback.
A kind of short wave communication digital voice receiving trap provided by the invention, this device comprises controls processing module, voice management module and audio reception device, and described control processing module comprises data reception module, SPI interface module, acoustic code demoder and audio frequency D/A module;
Described data reception module sends to acoustic code demoder by the audio digital signals receiving, and also by SPI interface module, sends to voice management module; Described voice management module is stored the audio digital signals receiving, and the audio digital signals of storage is sent to acoustic code demoder; Described acoustic code demoder is issued audio frequency D/A module after the audio digital signals receiving is decoded, and described audio frequency D/A module carries out decoded audio digital signals to send to audio reception device after digital-to-analog conversion.
Receive during speech, the data to be decoded that received by data reception module are leaded up to SPI interface module and are given voice management module stores, and a road is reduced into analogue audio frequency through audio frequency D/A after acoustic code decoding, is sent to audio reception device.Can recall the reception speech data to be decoded of storage, by acoustic code, decode, after audio frequency D/A conversion, be sent to audio reception device and carry out playback, as shown in Figure 5, the right horizontal stripe is the indication that receives speech at the interface of acoustic playback.
A kind of short wave communication digital voice control transmission method provided by the invention, comprises the steps:
When as shown in Figure 3, short wave communication digital voice dispensing device speech sends:
(1) original state;
(2) judge whether to send audio analog signals, if so, jump into step (3), otherwise, jump into step (6);
(3) audio analog signals that will send is carried out to A/D sampling, and the audio digital signals that sampling is obtained carries out acoustic code coding;
(4) audio digital signals after coding is stored;
(5) audio digital signals after coding is carried out to agreement framing, the voice data after agreement framing is counted to biography mode with ARQ and send;
(6) judge whether the audio digital signals of storage to be sent, if so, the audio digital signals of storage is carried out to ARQ, count biography mode after agreement framing and send; Otherwise jump into step (7);
(7) judge whether to carry out voice reproducing to the audio digital signals of storage, if so, the audio digital signals of storage decoded, be reduced into audio analog signals after D/A conversion, be sent to audio reception device and carry out voice reproducing; Otherwise return to step (1) original state;
(8) finish;
When as shown in Figure 4, short wave communication digital voice dispensing device speech receives:
(1) original state;
(2) judgement need to be carried out voice reproducing to the audio digital signals to be decoded of storage, if so, jumps into step (6); Otherwise jump into step (3)
(3) judge whether to receive that ARQ counts the voice data that biography mode transmits, if so, jump into step (4); Otherwise return to original state;
(4) voice data receiving is resolved and obtain audio digital signals to be decoded;
(5) audio digital signals to be decoded is stored;
(6) audio digital signals to be decoded is decoded, and change and be reduced into audio analog signals by D/A, be then sent to audio reception device and carry out audio frequency broadcasting;
(7) finish.
The above is only the preferred embodiment of the present invention; be noted that for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.
Claims (7)
1. a short wave communication digital voice dispensing device, is characterized in that: this device comprises audio frequency transmitting apparatus, controls processing module, voice management module and audio reception device; Described control processing module comprises audio A/D module, acoustic code scrambler, data transmission blocks, acoustic code demoder, SPI interface module and audio frequency D/A module;
Described audio frequency transmitting apparatus sends audio A/D module by audio analog signals, described audio A/D module is carried out after analog to digital conversion the audio analog signals of accepting, the audio digital signals of acquisition is sent to acoustic code scrambler, described acoustic code scrambler sends to data transmission blocks after the audio digital signals receiving is encoded, and sends to voice management module by SPI interface module simultaneously; Described data transmission blocks is counted biography mode by the audio digital signals after coding with ARQ and is sent; The audio digital signals of described voice management module after to the coding receiving stored, and the audio digital signals of storage is sent to acoustic code demoder by SPI interface module, described acoustic code demoder is decoded to the audio digital signals receiving, and send to audio frequency D/A module, described audio frequency D/A module is carried out digital-to-analog conversion to decoded audio digital signals, and sends to audio reception device to carry out voice reproducing the audio analog signals of acquisition.
2. a kind of short wave communication digital voice dispensing device according to claim 1, is characterized in that: described acoustic code scrambler and acoustic code demoder adopt and be greater than 600bps rate vocoder.
3. a kind of short wave communication digital voice dispensing device according to claim 2, is characterized in that: described acoustic code scrambler and acoustic code demoder adopt 2400bps vocoder.
4. a short wave communication digital voice receiving trap, it is characterized in that: this device comprises controls processing module, voice management module and audio reception device, and described control processing module comprises data reception module, SPI interface module, acoustic code demoder and audio frequency D/A module;
Described data reception module sends to acoustic code demoder by the audio digital signals receiving, and also by SPI interface module, sends to voice management module; Described voice management module is stored the audio digital signals receiving, and the audio digital signals of storage is sent to acoustic code demoder; Described acoustic code demoder is issued audio frequency D/A module after the audio digital signals receiving is decoded, and described audio frequency D/A module carries out decoded audio digital signals to send to audio reception device after digital-to-analog conversion.
5. a kind of short wave communication digital voice receiving trap according to claim 4, is characterized in that: described acoustic code demoder adopts and is greater than 600bps rate vocoder.
6. a kind of short wave communication digital voice receiving trap according to claim 5, is characterized in that: described acoustic code demoder adopts 2400bps vocoder.
7. a short wave communication digital voice transmission method, is characterized in that comprising the steps:
Transmitting terminal:
(1) original state;
(2) judge whether to send audio analog signals, if so, jump into step (3), otherwise, jump into step (6);
(3) audio analog signals that will send is carried out to A/D sampling, and the audio digital signals that sampling is obtained carries out acoustic code coding;
(4) audio digital signals after coding is stored;
(5) audio digital signals after coding is carried out to agreement framing, the voice data after agreement framing is counted to biography mode with ARQ and send;
(6) judge whether the audio digital signals of storage to be sent, if so, the audio digital signals of storage is carried out to ARQ, count biography mode after agreement framing and send; Otherwise jump into step (7);
(7) judge whether to carry out voice reproducing to the audio digital signals of storage, if so, the audio digital signals of storage decoded, be reduced into audio analog signals after D/A conversion, be sent to audio reception device and carry out voice reproducing; Otherwise return to step (1) original state;
(8) finish;
Receiving end:
(1) original state;
(2) judgement need to be carried out voice reproducing to the audio digital signals to be decoded of storage, if so, jumps into step (6); Otherwise jump into step (3)
(3) judge whether to receive that ARQ counts the voice data that biography mode transmits, if so, jump into step (4); Otherwise return to original state;
(4) voice data receiving is resolved and obtain audio digital signals to be decoded;
(5) audio digital signals to be decoded is stored;
(6) audio digital signals to be decoded is decoded, and change and be reduced into audio analog signals by D/A, be then sent to audio reception device and carry out audio frequency broadcasting;
(7) finish.
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Cited By (1)
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| CN111128207A (en) * | 2019-12-31 | 2020-05-08 | 陕西烽火电子股份有限公司 | Self-listening and self-loop calling box and calling method thereof |
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