CN103714823B - A kind of self adaptation subsurface communication method based on integrated voice coding - Google Patents
A kind of self adaptation subsurface communication method based on integrated voice coding Download PDFInfo
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Abstract
The present invention relates to a kind of self adaptation subsurface communication method based on integrated voice coding, the voice of underwater sound communication system information source end input are launched through chnnel coding, modulation, power amplifier and underwater acoustic transducer after being processed by two-way hybrid coding and decision device; After underwater acoustic channel transmission, stay of two nights end is sent into two-way hybrid decoding after receiving signal by underwater acoustic transducer after filter amplifier amplification, channel equalization, channel estimating, demodulation, channel-decoding; Before carrying out the underwater sound communication of voice coding/speech recognition, send one group of midamble code by the decision device of the information source end of aquanaut's first, channel arrives the stay of two nights end of aquanaut's second; After the stay of two nights end of aquanaut's second is processed the characteristic of channel of acquisition, result is transmitted to the information source end of aquanaut's second, the stay of two nights end that arrives again aquanaut's first through underwater acoustic channel, the decision device of aquanaut's first is adjudicated according to received characteristic of channel energy number. The present invention can realize the speech quality suitable with mobile communication.
Description
Technical field
The invention belongs to a kind of voice communication system. Be particularly related to a kind of self adaptation subsurface communication method based on integrated voice coding.
Background technology
All underwater sound communication modes are generally divided into analog-and digital-two kinds, wherein analogue communication mode is main mainly with AM single-side-band modulation system, when channel belongs to strict band in limited time, conventionally adopt analogue communication mode just can reach the bandwidth requirement of voice communication, but analogue communication mode is second-rate, bad when speech intelligibility fashion, can not be adapted to complexity and changeable noisy channels. Conventionally ocean channel has the characteristic of strong noise background, low carrier frequency, extremely limited bandwidth and time-space-change of frequency, and these characteristics make underwater acoustic channel become one of the most severe so far communication channel. A lot of research has been done in the channel stability of underwater sound communication, modulator approach by lot of domestic and foreign research institution, but the underwater sound communication of conventional method is difficult to break through the technical barrier of stable channels bandwidth and reliable communication in real time. , consider from information source angle for this reason, information source is encoded, the data volume of compressed voice signal significantly, the reliable and stable voice communication system that the speed that realizing provides with underwater acoustic channel matches.
In actual underwater sound communication, Partial Sea Area can only communicate with the speed below 0.8kbps, because the voice coding speed below 2.4kbps speed is too low, excitation information relative deficiency, make the correlation of its voice quality and ambient noise large, be not easy structure and have the encryption algorithm that applicability is larger, voice coding there is no international standard at present lower than the voice coding scheme of 2.4kbps speed at present.
Speech Coding at Low Bit Rates has adopted the method more more complicated than conventional codec to divide and reconstruct the driving source of voice, and what propose the earliest is linear predictive coding model, constantly has on this basis new encryption algorithm to propose. Mainly contain both at home and abroad at present and use code book QCELP Qualcomm technology, multi band excitation model, MELP speech coding technology and these four kinds main low rate coding algorithms of original shape waveform interpolation method as driving source, researchers have launched positive exploration and research on this basis, but the voice signal after low rate encoding and decoding, the robust ability of the naturalness of its voice and tolerance ambient noise has very large defect, cannot meet preferably the communicating requirement of underwater acoustic channel. In numerous voice information source compression coding technologies, speech recognition is undoubtedly the algorithm that compression ratio is the highest.
Few about going back of underwater voice communication technical research in the world at present, is generally all to carry out compressed encoding, modulation, transmission and demodulating and decoding according to the mode of traditional wireless communication. find at present about speech recognition technology and apply to 2 sections, the patent of underwater communications system and document: the phonetic synthetic technology of having applied speech recognition technology and voice in the underwater voice communication method of a kind of low code check of Chinese Patent Application No. (200810064290.0), first convert the voice signal of transmitting terminal to the Chinese phonetic alphabet or ASCII character corresponding to the Chinese phonetic alphabet by speech recognition system, then carry out sending after chnnel coding, receiving terminal carries out demodulation code, again according to demodulation Pinyin code or Chinese character pronunciation code out, call the corresponding phonetic of sound bank or Chinese character pronunciation information. utilize Speech Synthesis Algorithm that pronunciation is synthesized to voice signal output, document " speech recognition is the utilization in underwater sound communication in synthetic technology ", communication theory in 2003 and signal are processed nd Annual Meeting collection, in March, 2008, P434 ~ 439, Cheng En etc., its thinking is to convert voice signal to text signal, utilize ready-made ViaVoice identification software and speech synthesis software, realize underwater voice communication, the ViaVoice software of selecting can only apply to all-purpose computer, what send is character code, and phoneme synthesizing method does not have explanation, is not suitable for being applied to the voice call between microminiature carrier and aquanaut under water.
Summary of the invention
The object of the present invention is to provide a kind of self adaptation subsurface communication method based on integrated voice coding.
Carry out voice communication in the underwater environment of bad channel time, adopt speech recognition and synthetic technology, the speech text data that voice signal are converted into utmost point low rate at transmitting terminal are transmitted by underwater acoustic channel, the speech text data that receive are synthesized voice by receiving terminal, because the data transfer rate of the speech text data after identification is extremely low, can utilize low code check error correction coding to improve the characteristic of channel, reach reliable and stable transmission, this is a kind of new approaches that realize the digital communication of underwater sound voice low rate. Due to the restriction of aquanaut's communication equipment hardware under Underwater Acoustic Environment, the well behaved speech recognition system of industry is all the continuous speech recognition modeling technique framework that adopts HMM (HMM), and under water under communication environment, owing to being subject to ambient noise, the restriction of the aspects such as computational complexity, is directly used traditional algorithm and model to can not meet practical demand far away.
According to the characteristic of underwater sound communication and ocean channel, the present invention utilizes speech recognition/speech coding technology, voice are converted into voice recognition data that bandwidth requirement is extremely low and compared with the vocoded data of low rate, and according to the characteristic of channel select adaptively voice recognition data/vocoded data carry out two-way hybrid coding or voice recognition data separately two kinds of modes of coding transmit, realize flexibly the voice communication being adapted under different communication distance, different communication mode, different communication demand condition, the system architecture of data communication and mode.
The self adaptation subsurface communication method based on integrated voice coding that the present invention proposes, realize by self-adaptive underwater communication system, described communication system is by two-way hybrid coding 1, decision device 2, chnnel coding 3, modulator 4, power amplifier 5, the first underwater acoustic transducer 6, underwater acoustic channel 7, the second underwater acoustic transducer 8, filter amplifier 9, channel equalization 10, channel estimating 11, demodulator 12, channel-decoding 13 and two-way hybrid decoding 14 form, wherein: the input of two-way hybrid coding 1 connects phonetic entry, output connects decision device 2, the output connecting channel coding 3 of decision device 2, the output of chnnel coding 3 connects modulator 4, the output of modulator 4 connects power amplifier 5, the output of the first underwater acoustic transducer 6 connects respectively power amplifier 5 and underwater acoustic channel 7, the output of underwater acoustic channel 7 connects the input of the second underwater acoustic transducer 8, the output of the second underwater acoustic transducer 8 connects filter amplifier 9, the output of filter amplifier 9 is connecting channel balanced 10 and channel estimating 11 respectively, the output of channel estimating 11 connects respectively demodulator 12 and channel equalization 10, demodulator 12 output connecting channel decodings 13, the output of channel-decoding 13 connects two-way hybrid decoding 14, voice output is carried out in two-way hybrid decoding 14, concrete steps are as follows:
(1) voice of underwater sound communication system information source end input are launched through chnnel coding, modulation, power amplifier and underwater acoustic transducer after being processed by two-way hybrid coding and decision device;
(2) after underwater acoustic channel transmission, stay of two nights end is sent into two-way hybrid decoding after receiving signal by underwater acoustic transducer after filter amplifier amplification, channel equalization, channel estimating, demodulation, channel-decoding;
(3) before carrying out the underwater sound communication of voice coding/speech recognition, send one group of midamble code by the decision device of the information source end of aquanaut's first, channel arrives the stay of two nights end of aquanaut's second;
(4) after the stay of two nights end of aquanaut's second is processed the characteristic of channel of acquisition, result is transmitted to the information source end of aquanaut's second, the stay of two nights end that arrives again aquanaut's first through underwater acoustic channel, the decision device of aquanaut's first is adjudicated according to received characteristic of channel energy number.
In the present invention, information source end adopts speech recognition and two kinds of modes of low-bit-rate speech coding coding to compress information source; Voice signal is divided into two-way after pretreatment, sends into respectively data branch road and voice leg. In data branch road, the laggard row speech recognition of speech recognition, output voice recognition data signal. In voice leg, speech signal parameter carries out low-bit-rate speech coding coding after extracting, output vocoded data. Voice recognition data and vocoded data judge the current characteristic of channel according to decision device, select voice recognition data/vocoded data to carry out two-way hybrid coding or the independent coded system transmission of voice recognition data according to judged result.
In the present invention, data after stay of two nights end two-way simultaneous interpretation system module receiving terminal channel-decoding, the coded system that judgement receives, if voice recognition data/vocoded data two-way hybrid coding, taking decoded encoding speech signal as main, voice recognition data synthetic speech signal is auxiliary output; If voice recognition data is encoded separately, the voice signal after synthesizing with voice recognition data is exported.
The present invention intends taking underwater voice communication as application target, carries out the underwater sound communication architectural study based on voice coding/speech recognition. Its basic conception is that low-bit-rate speech coding coding combines with speech recognition and synthetic technology, and voice coding communication is provided in the time that communication channel conditions is good, can realize the speech quality suitable with mobile communication; In the time that communication channel conditions is poor, provides and can adapt to the more speech recognition of low data rate and synthetic voice communication (now, the naturalness of voice, the degree that conforms to speaker's voice will reduce). Such communication construction can ensure on the basis of current water sound communication technique, realizes communication more at a distance.
Brief description of the drawings
Fig. 1 is the self-adaptive underwater communication system the general frame of voice coding/speech recognition two-way of the present invention simultaneous interpretation.
Fig. 2 is information source end two-way simultaneous interpretation system module block diagram of the present invention.
Fig. 3 is stay of two nights end two-way simultaneous interpretation system module block diagram of the present invention.
Number in the figure: 1 is two-way hybrid coding, 101 is pretreatment module, 102 is feature extraction, 103 is sound identification module, 104 is data coding module, 105 is parameter extraction module, 106 is voice coding module, 2 is decision device, 3 is chnnel coding, 4 is modulator, 5 is power amplifier, 6 is the first underwater acoustic transducer, 7 is underwater acoustic channel, 8 is the second underwater acoustic transducer, 9 is filter amplifier, 10 is channel equalizer, 11 is channel estimator, 12 is demodulator, 13 is channel-decoding, 14 is two-way hybrid decoding, 1401 is coded system decision device, 1402 is data decode module, 1403 is language synthesis module, 1404 is tone decoding module.
Detailed description of the invention
Further illustrate the present invention below by accompanying drawing.
Embodiment 1: first before carrying out the underwater sound communication of voice coding/speech recognition, send one group of midamble code by the decision device of the information source end of aquanaut's first, channel arrives the stay of two nights end of aquanaut's second. After aquanaut's second stay of two nights end is processed the characteristic of channel of acquisition, result is transmitted to the information source end of aquanaut's second, channel arrives the stay of two nights end of aquanaut's first again, and the decision device 2 of aquanaut's first is adjudicated according to received characteristic of channel energy number.
In accompanying drawing 1, the voice of underwater sound communication system information source end input are launched through chnnel coding 3, modulation 4, power amplifier 5 and underwater acoustic transducer 6 after being processed by information source end two-way simultaneous interpretation system module (two-way hybrid coding 1 and decision device 2), after underwater acoustic channel 7 transmission, stay of two nights end receives by underwater acoustic transducer 8 the egress two-way simultaneous interpretation system module (two-way hybrid decoding 14) of delivering letters after filter and amplification 9, channel equalization 10, channel estimating 11, demodulation 12, channel-decoding 13 after signal.
In accompanying drawing 2, information source end adopts speech recognition and two kinds of modes of low-bit-rate speech coding coding to compress information source; Voice signal is divided into two-way after pretreatment 101, sends into respectively data branch road and voice leg. In data branch road, the laggard row speech recognition 106 of speech recognition 105, output voice recognition data signal. In voice leg, speech signal parameter extracts 102 laggard row phonetic syntheses 103, then the voice after synthetic is carried out to low-bit-rate speech coding coding 104, output vocoded data. Voice recognition data and vocoded data judge the current characteristic of channel according to decision device 2, select voice recognition data/vocoded data to carry out two-way hybrid coding or the independent coded system transmission of voice recognition data according to judged result.
Data in accompanying drawing 3 after stay of two nights end two-way simultaneous interpretation system module receiving terminal channel-decoding, carry out coded system judgement 1401 by the data that receive, if voice recognition data/vocoded data two-way hybrid coding, voice signal taking after tone decoding 1404 as main, the rear synthetic voice signal 1403 of data decode 1402 is auxiliary output; If voice recognition data is encoded separately, voice signal is exported with the signal after the laggard row phonetic synthesis 1403 of data decode 1402.
Claims (2)
1. the self adaptation subsurface communication method based on integrated voice coding, it is characterized in that described method realizes by self-adaptive underwater communication system, described underwater sound communication system is by two-way hybrid coding (1), decision device (2), chnnel coding (3), modulator (4), power amplifier (5), the first underwater acoustic transducer (6), underwater acoustic channel (7), the second underwater acoustic transducer (8), filter amplifier (9), channel equalization (10), channel estimating (11), demodulator (12), channel-decoding (13) and two-way hybrid decoding (14) composition, wherein: the input of two-way hybrid coding (1) connects phonetic entry, output connects decision device (2), the output connecting channel coding (3) of decision device (2), the output of chnnel coding (3) connects modulator (4), the output of modulator (4) connects power amplifier (5), the output of the first underwater acoustic transducer (6) connects respectively power amplifier (5) and underwater acoustic channel (7), the output of underwater acoustic channel (7) connects the input of the second underwater acoustic transducer (8), the output of the second underwater acoustic transducer (8) connects filter amplifier (9), the output of filter amplifier (9) is connecting channel equilibrium (10) and channel estimating (11) respectively, the output of channel estimating (11) connects respectively demodulator (12) and channel equalization (10), the output connecting channel decoding (13) of demodulator (12), the output of channel-decoding (13) connects two-way hybrid decoding (14), voice output is carried out in two-way hybrid decoding (14), concrete steps are as follows:
(1) voice of underwater sound communication system information source end input are launched through chnnel coding, modulation, power amplifier and the first underwater acoustic transducer after being processed by two-way hybrid coding and decision device;
(2) after underwater acoustic channel transmission, stay of two nights end is sent into two-way hybrid decoding after receiving signal by the second underwater acoustic transducer after filter amplifier amplification, channel equalization, channel estimating, demodulation, channel-decoding;
(3) before carrying out the underwater sound communication of voice coding/speech recognition, send one group of midamble code by the decision device of the information source end of aquanaut's first, channel arrives the stay of two nights end of aquanaut's second;
(4) after the stay of two nights end of aquanaut's second is processed the characteristic of channel of acquisition, result is transmitted to the information source end of aquanaut's second, the stay of two nights end that arrives again aquanaut's first through underwater acoustic channel, the decision device of aquanaut's first is adjudicated according to received characteristic of channel energy number;
Wherein: information source end adopts speech recognition and two kinds of modes of low-bit-rate speech coding coding to compress information source; Voice signal is divided into two-way after pretreatment, sends into respectively data branch road and voice leg; In data branch road, the laggard row speech recognition of speech recognition, output voice recognition data signal; In voice leg, speech signal parameter carries out low-bit-rate speech coding coding after extracting, output vocoded data; Voice recognition data and vocoded data judge the current characteristic of channel according to decision device, select voice recognition data/vocoded data to carry out two-way hybrid coding or the independent coded system transmission of voice recognition data according to judged result.
2. method according to claim 1, it is characterized in that the data after stay of two nights end two-way simultaneous interpretation system module receiving terminal channel-decoding, the coded system that judgement receives, if voice recognition data/vocoded data two-way hybrid coding, taking decoded encoding speech signal as main, voice recognition data synthetic speech signal is auxiliary output; If voice recognition data is encoded separately, the voice signal after synthesizing with voice recognition data is exported.
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| CN103971695B (en) * | 2014-05-23 | 2017-03-01 | 厦门大学 | A kind of underwater digital voice communication system of channel self-adapting and its method |
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| CN106385393A (en) * | 2016-09-07 | 2017-02-08 | 厦门大学 | OFDM underwater voice communication method based on frequency domain Chirp spread spectrum |
| CN109524004B (en) * | 2018-12-29 | 2022-03-08 | 思必驰科技股份有限公司 | Method for realizing parallel transmission of multi-channel audio and data, external voice interaction device and system |
| CN110049427B (en) * | 2019-05-16 | 2023-06-23 | 上海纽菲斯信息科技有限公司 | Method for realizing simultaneous detection of multiple earphones |
| CN110364170B (en) * | 2019-05-29 | 2024-01-30 | 平安科技（深圳）有限公司 | Voice transmission method, voice transmission device, computer device and storage medium |
| CN111028825A (en) * | 2020-01-09 | 2020-04-17 | 哈尔滨工程大学 | Underwater sound digital voice communication device and method based on offline voice recognition and synthesis |
| CN112235054B (en) * | 2020-10-15 | 2021-06-08 | 厦门大学 | Full-duplex underwater sound digital voice communication demonstration device and method thereof |
| CN115112226A (en) * | 2022-06-10 | 2022-09-27 | 同济大学 | Non-stationary underwater acoustic signal self-adaptive detection method under intelligent aquaculture scene |
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