CN102970123A - Underwater acoustic communication apparatus with timesharing-implemented multichannel time reversal - Google Patents

Abstract

The invention discloses an underwater acoustic communication apparatus with timesharing-implemented multichannel time reversal and relates to underwater acoustic communication. According to the underwater acoustic communication apparatus with the timesharing-implemented multichannel time reversal, multichannel time reversal and channel multipath effect inhibition are realized through timesharing retransmission. The underwater acoustic communication apparatus is provided with a transmitting part and a receiving part, wherein the transmitting part is provided with an information code element input interface, a spread spectrum modulation module, a convolution module, a probe signal generator, a frame synchronizing signal generator, a signal framing module, a power amplifier and a transmitting transducer; and the receiving part is provided with a multi-element receiving array, a pre-processing module, a channel switcher, an A/D (Analog to Digital) converter, a synchronization module, a time reversal preprocessor, a serial/parallel multichannel combiner and a data decoder. The underwater acoustic communication apparatus has the advantages that multipath focusing of underwater acoustic channels can be realized by a digital processor chip in real time, the complexity of a system for realizing the multichannel time reversal in the underwater acoustic communication apparatus is reduced, and the time selective fading caused by strong time-varying underwater acoustic channels can be inhibited.

Description

A kind of timesharing realizes the multichannel underwater acoustic communication set of time reversal

Technical field

The present invention relates to a kind of underwater sound communication, especially relate to a kind of timesharing and realize the multichannel underwater acoustic communication set of time reversal.

Background technology

Day by day increase along with the fields such as current marine resources development, marine environment stereoscopic monitoring and ocean national defense safety obtain with the demand of transmitting marine information, water sound communication technique has become the important front edge of Marine High-technology.And the underwater acoustic channel multipath disturbs strong, channel response poor stability, has typical Space Time-frequency domain non-stationary property, and the design of high-performance underwater sound communication system is brought very large difficulty.

Time reversal technology can operational use time, the space-focusing effect suppresses multipath and disturbs, and becomes the in recent years study hotspot of underwater sound communication and signal process field.Difference according to processing mode, time reversal, technology can be divided into initiatively time reversal and passive time reversal two classes: emission sound source of the former receiver needs and receiving array close the polynary battle array of putting, carry out retransmitting after time reversal for receiving that transmitter transmits, so that sound field focuses at sound source position; The probe signals that the latter utilization receives obtains channel multi-path information, and constructs preposition preprocessor and carry out to received signal multipath focusing.Because the anti-technology signal only needs one-way transmission when passive, and need not to adopt transmitting-receiving to close to put array, technical realization is simpler, thereby has obtained widely research.(the Chen Dongsheng such as Chen Dongsheng, Tong Feng, Xu Xiaomei. the time anti-combined channel balanced underwater sound communication system research [J]. acoustic technique .2011,30 (3): 195-197) in point-to-point communication system, utilize when passive anti-joint equalization to resist interference, raising communication system energy.(the Gong Gaiyun such as Gong Gaiyun, Yao Wenbin, Pan Xiang. underwater sound communication anti-and that adaptive equalization is linked together is studied [J] when passive. acoustic technique .2010,29 (2): 129-134) utilize anti-when passive and adaptive equalization is linked together, in the phase coherence underwater communications system, shown reliability and the high efficiency of the method.(the H.C.Song such as H.C.Song, W.S.Hodgkiss, W.A.Kupermanet al.Multiuser Communications Using Passive Time Reversal.IEEE JOURNAL OF OCEANICENGINEERING.2007,32 (4): 915-926) anti-basis utilizes decision feedback equalization, PHASE-LOCKED LOOP PLL TECHNIQUE to realize multi-user's underwater acoustic information transmission when passive.(the G.F.Edelmann such as G.F.Edelmann, T.Akal, W.S.Hodgkiss et al., An initialdemonstration of underwater acoustic communication using time reversal.IEEE J.Oceanic Eng.2002,27 (3): anti-technology overcomes intersymbol interference effectively when 602-609) then utilizing under multipath channel.

Simultaneously, theoretical and experiment shows, when only using single receiving array unit to carry out the passive time reversal processing, affected greatly by the channel multipath characteristics, is difficult to obtain ideal performance.In order to improve the performance of time reversal processing, generally need to adopt many array elements to receive and carry out time reversal to reach preferably multipath focusing and intersymbol interference rejection.Chinese patent 200910072531.0 and 200910071516.4 all adopts array of multi-unit receiving to form the underwater sound communication that multichannel realizes suppressing multipath effect time reversal.But, because carrying out the repeatedly related operation of mass data in need to each passage in a plurality of receive paths, processes the multichannel time reversal processing, for carrying the extremely limited underwater acoustic communication sets of aspect resource such as power supply in all kinds of nodes under water, space, be difficult to realize that the real-time water sound communication that suppresses multipath effect is processed in counter-rotating based on multichannel.Therefore, multichannel underwater acoustic communication method time reversal has limited the application of multichannel technology time reversal in the actual realization of underwater acoustic communication set still based on multi-channel data being carried out off-line, rearmounted theory, the method research state of processing in numerous documents.

The sound communication method of turning one's coat when Chinese patent 2010105818403 proposes a kind of suitable mobile platform passive, the space diversity effect that repeat its transmission identical information frame obtains when utilizing the receiving-transmitting sides at least one party to move is carried out the multichannel time reversal processing, anti-preliminary treatment and merging when different relative positions reception signals are carried out, thereby can utilize single receiving hydrophone to realize that multichannel suppresses the effect that multipath disturbs time reversal, can reduce many array elements and receive the system complexity of bringing.But being receiving-transmitting sides, its prerequisite have at least a side to be kept in motion, otherwise the focusing effect that can't obtain to expect; On the other hand, be kept in motion owing to require to receive and dispatch at least at least one party, need in the method the Doppler effect that the transmitting-receiving motion is introduced is suppressed to process.

Summary of the invention

The object of the present invention is to provide by the timesharing repeat its transmission and realize that a kind of timesharing that multichannel suppresses channel multipath effect time reversal realizes the multichannel underwater acoustic communication set of time reversal.

The present invention is provided with radiating portion and receiving unit;

Described radiating portion is provided with information code element input interface, band spectrum modulation module, convolution module, probe signals generator, frame synchronousing signal generator, signal and becomes frame module, power amplifier and transmitting transducer; Described information code element input interface is connected with the input of band spectrum modulation module, the output of band spectrum modulation module is connected output and is connected with the input of convolution module with the probe signals generator, the input that signal becomes frame module is connected output with the output of the output of convolution module, probe signals generator respectively and is connected with frame synchronousing signal generator, the input of power amplifier, output become the output of frame module to be connected input with transmitting transducer with signal respectively to be connected.

Described receiving unit is provided with array of multi-unit receiving, pre-process module, censor key, A/D converter (ADC), synchronization module, time reversal preprocessor, serial/parallel multichannel combiner and data decoder; Described array of multi-unit receiving receives array element by at least 2 and forms, the output of array of multi-unit receiving is connected with the input of pre-process module, multi channel signals output after the processing of pre-process module connects the input of A/D converter (ADC) through censor key, the output of A/D converter (ADC) respectively with the input of synchronization module with time reversal preprocessor be connected input and be connected, the frame synchronizing signal output of synchronization module is connected with the frame synchronizing signal input of preprocessor time reversal, time reversal preprocessor each channel data input of finishing the serial/parallel multichannel combiner of anti-processing signals output termination when passive, reception signal output part after anti-during the multichannel of serial/parallel multichannel combiner connects the input of data decoder, carry out data decode by data decoder, recover initial data.

Negative side's method is compared during with present existing underwater sound communication multichannel, and timesharing multichannel underwater acoustic communication set time reversal that the present invention proposes has two outstanding advantages:

First, owing to adopt mode that repeat its transmission identical information frame switches in conjunction with multichannel to realize timesharing multichannel time reversal, can on a slice numerical processor chip, focus on by the underwater acoustic channel multipath of real-time implementation superior performance, greatly reduce system complexity anti-when realizing multichannel in the underwater acoustic communication set, can significantly improve the performance of underwater acoustic communication set simultaneously;

Second, because identical information frame repeat its transmission, can obtain simultaneously the effect of time diversity, become the time selective fading that underwater acoustic channel causes in the time of can suppressing strong, anti-integrated use during by time diversity, multichannel, the underwater acoustic communication set that the present invention proposes became underwater acoustic channel and has preferably rejection multipath, time.

Description of drawings

Fig. 1 is that the radiating portion of the embodiment of the invention forms schematic diagram.

Fig. 2 is that the receiving unit of the embodiment of the invention forms schematic diagram.

Fig. 3 is the frame design drawing that transmits of the embodiment of the invention.

Fig. 4 is the preposition modular circuit schematic diagram of embodiment of the invention receiving unit.

Fig. 5 is the interface circuit schematic diagram of channel to channel adapter, analog to digital converter and the DSP of embodiment of the invention receiving unit.

Fig. 6 is that the DSP control channel selector of the embodiment of the invention is realized each passage timesharing switching principle figure.

Embodiment

For technology contents of the present invention, feature, advantage are become apparent more, the present invention is further illustrated in connection with accompanying drawing for following examples.

Referring to Fig. 1 and 2, the embodiment of the invention is provided with radiating portion and receiving unit;

Described radiating portion is provided with information code element input interface 11, band spectrum modulation module 12, convolution module 13, probe signals generator 14, frame synchronousing signal generator 15, signal and becomes frame module 16, power amplifier 17 and transmitting transducer 18; Described information code element input interface 11 is connected with the input of band spectrum modulation module 12, the output that the output of band spectrum modulation module 12 is connected with the probe signals generator is connected with the input of convolution module 13, signal becomes the input of frame module 16 to be connected with the output of convolution module 13, the output that the output of probe signals generator 14 is connected with frame synchronousing signal generator respectively, and the input of power amplifier 17, output become the input that the output of frame module 16 is connected with transmitting transducer to be connected with signal respectively.

Described receiving unit is provided with array of multi-unit receiving 21, pre-process module 22, censor key 23, A/D converter (ADC) 24, synchronization module 25, time reversal preprocessor 26, serial/parallel multichannel combiner 27 and data decoder 28; Described array of multi-unit receiving 21 receives array element by at least 2 and forms, the output of array of multi-unit receiving 21 is connected with the input of pre-process module 22, multi channel signals output after the processing of pre-process module 22 connects the input of A/D converter (ADC) 24 through censor key 23, the output of A/D converter (ADC) 24 is connected with the input that time reversal, preprocessor was connected with the input of synchronization module 25 respectively, the frame synchronizing signal output of synchronization module 25 with time reversal preprocessor 26 frame synchronizing signal input be connected, time reversal preprocessor 26 each channel data input of finishing the serial/parallel multichannel combiner 27 of anti-processing signals output termination when passive, reception signal output part after anti-during the multichannel of serial/parallel multichannel combiner 27 connects the input of data decoder 28, carry out data decode by data decoder 28, recover initial data.Described pre-process module is provided with preamplifier 221 and filter 222.

Below provide operation principle of the present invention:

1. radiating portion:

Transmit and adopt direct sequence spread spectrum differential phase modulation (DS-DBPSK), sample rate is 96kHz, and carrier frequency is 15kHz, and bandwidth is 13～18kHz, adopts the m sequence spread spectrum, and the length of m sequence is 63, and each symbol width is 15.75ms; Probe signals is for to obtain the probe sequence that length is 23.8ms by 63 m sequence spread spectrums; Frame synchronizing signal is low side frequency 13kHz, high-end frequency 18kHz, the linear FM signal of length 30ms.In the signal frame format parameter: protection is spaced apart 30ms, and information frame is comprised of after band spectrum modulation the 200bit code element, and namely the length of each information frame is 3.15s, and present embodiment adopts the mode that repeats in time N=4 time to carry out the time-division repeat its transmission.Probe signals, frame synchronizing signal produce by the mode of digital signal processor with software programming in the present embodiment.

Transmitting transducer in the embodiment of the invention can be state-run the column type piezoelectric ceramic underwater acoustic transducer of centre frequency 13～18kHz of producing of 612 factories form, adopt power amplification circuit well known in the art to carry out the signal emission.

2. receiving unit:

At first select default channel (being made as in an embodiment 1 passage) to adopt the copy related operation that input signal is carried out frame synchronization and catch, whether whether arrive synchronously above setting the thresholding judgment frame, and determine the frame synchronization start time by judging the copy correlated results.

After setting up frame synchronization, anti-implementation during the time division multichannel that adopts for underwater acoustic communication set of the present invention, according to the frame time order that transmits, i passage (i=1 in the control channel selector selective reception array successively, 2,3 ... N) corresponding probe signals input digit processor obtains the probe pin p after each receive path of array transmits _Ir(t), it is carried out namely obtain after time reversal the time anti-preprocessor coefficient p of each passage _Ir(-t).

After finishing each passage probe signals and gathering, successively i passage in the control channel selector selective reception array (i=1,2,3 ... N) corresponding informance frame signal input digit processor.The impulse response of supposing i channel in the receiving array is h _i(t), satisfy randomness, The expression convolution algorithm, then the i passage receives information code element s _Ir(t) be

$s_{\mathrm{ir}}\left(t\right)=s\left(t\right)\⊗h_i\left(t\right)+n_{\mathrm{is}}\left(t\right)---\left(1\right)$

In the formula (1), n _Is(t) for being superimposed upon the interference noise on the information signal, with each the channel information frame s that receives _Ir(t) the time anti-preprocessor p of process respective channel _Ir(-t) is namely with p _Ir(-t) made convolution algorithm and can be got:

${r_i}^{\′}\left(t\right)=s_{\mathrm{ir}}\left(t\right)\⊗p_{\mathrm{ir}}(-t)=s\left(t\right)\⊗h_i\left(t\right)\⊗h_i(-t)\⊗p_i(-t)+n_{i1}\left(t\right)---\left(2\right)$

N in the formula (2) _1i(t) be the noise jamming item,

For the time each channel bank response after anti-the focusing, approximate δ (t).

For the p among the cancellation result _i(-t) is with r _i' (t) with probe signals p _i(t) do convolution algorithm, have

$r_i\left(t\right)={r_i}^{\′}\left(t\right)\⊗p_i\left(t\right)\≈s\left(t\right)\⊗\mathrm{\δ}\left(t\right)\⊗\mathrm{\δ}\left(t\right)+n_i\left(t\right)---\left(3\right)$

Convolution algorithm in this step is arranged on the convolution module of transmitting terminal and carries out the real-time operation amount that needs to reduce the receiving terminal demodulation in the technical scheme that the present invention proposes.N in the formula (3) _i(t) be the noise jamming item of i passage:

$n_i\left(t\right)=n_{1i}\left(t\right)\⊗p_i\left(t\right)---\left(4\right)$

Then, after switching by passage, in the receiving array reception signal of each passage one by one through respective channel separately the time obtain the time inverted signal r of corresponding each passage behind the anti-preprocessor _i(t), wherein the noise jamming item is n _i(t).

Serial/parallel multichannel combiner then according to the frame emission sequential during with each passage of one road serial input anti-information signal frame go here and there and change, and signal after anti-during each multichannel after changing and noise jamming item are merged processing, it is processed expression formula and is:

$s^{\′}\left(t\right)=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{r}_i\left(t\right)---\left(5\right)$

$n^{\′}\left(t\right)=\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{n}_i\left(t\right)---\left(6\right)$

From formula (1)～(6), can find out, when the time division multichannel that the present invention adopts under the anti-processing scheme, because repeat its transmission identical information frame, anti-treatment effect when receiving terminal switches each input channel and can realize same multichannel by channel to channel adapter.That is: the time inverse channel of original transmitted signal s (t) process is actual is the auto-correlation of channel impulse response and the autocorrelative convolution of probe signals, when sound channel multi-path when comparatively the self correlated peak of complexity and probe signals is sharp-pointed, the anti-channel that focuses on when this channel can be approximated to be, this moment s'(t) can be approximated to be the signal s (t) when sending.Multi channel signals through separately the time merge behind the anti-device, not only signal is focused on the elimination multipath, restore primary signal, and improved the gain of signal on the spatially time.And herein in the reason process, background noise Xiang Ze is because the irrelevance of each channel noise, after merging by establishment.

Finished multipath focusing after anti-the processing during information frame process time division multichannel, greatly suppressed the interference that multipath effect causes, after information frame during multichannel after anti-the processing is sent into data decoder, adopt algorithm well known in the art in dsp chip, to carry out despreading, the demodulation process of DS-DBPSK signal, obtaining information code element.

On underwater acoustic communication set hardware is realized, receive in the embodiment of the invention underwater acoustic transducer battle array by 4 vertically lay, broadband reception hydrophone that state-run 612 factories produce forms, i.e. receiving array number N=4, the spacing 1.5m in the array between adjacent two hydrophones.Each forms pre-process module in the module and is comprised of the MAX274 switching capacity filter chip of the preposition amplification chip of the U.S. AD620 of AD company low noise, TL084 operational amplifier chip, Maxium company, and wherein the MAX273 switching capacity filter is set to the band pass filter of passband 13～18kHz.Physical circuit as shown in Figure 4.Be divided into A through the output signal behind preposition amplification, the bandpass filtering, B, C, D 4 tunnel sends into the further channel selector.

Channel to channel adapter, modulus conversion chip are comprised of 4052 chips, AD9851DDS chip and MAX153 modulus conversion chip, and the square-wave signal that its function realizes the input of timesharing multichannel for the switching by each passage and DDS chip output frequency is 96kHz under the setting of DSP is used for the control modulus conversion chip input signal is carried out analog-to-digital conversion.4052, the connecting circuit figure between AD9851DDS chip, MAX153 modulus conversion chip and the TMS320C6713 processor as shown in Figure 5.At initial phase, the TMS320C6713 processor is by IO mouth GP0, GP1, GP2, GP3 arranges the AD9851DDS chip pin, and type and the frequency of AD9851 chip output pin output waveform is set, output type is square wave in the present embodiment, and the frequency of oscillation of output square wave is set to f _s=96kHz.

After setting up frame synchronization, the TMS320C6713 processor is by IO mouth GP8, GP9 carries out input channel control to the channel selecting end of channel to channel adapter chip 4052, be the A that dsp chip passes through 4052 chip controls array of multi-unit receivings, B, C, the probe of D4 channel signal, information signal frame one by one timesharing input follow-up modulus conversion chip and DSP processing.Passage timesharing switching principle as shown in Figure 5, after setting up frame synchronization, chronological order according to frame emission middle probe signal and information signal frame repeat its transmission, select successively A, B, C, the probe signals of each passage of D and information signal frame receive signal by multichannel behind the channel to channel adapter and are converted to the corresponding probe of each passage, the information signal frame that a passage is arranged one by one.The probe of grey square frame representative, information pointer signal are the input channel that each moment channel to channel adapter is chosen among Fig. 6, export one by one through probe signals, the information pointer signal of each passage after the channel selecting as can be seen from Figure 6.After each channel data goes out one by one by the channel to channel adapter timesharing, greatly reduce the operand that computing time reversal is processed in real time, be convenient to the real-time implementation of follow-up time counter-rotating convolution preliminary treatment computing on a slice dsp chip.

Enter modulus conversion chip and dsp interface circuit through signal after the channel to channel adapter selection input channel.As shown in Figure 5, the connected mode between AD9851DDS chip, MAX153 modulus conversion chip and the TMS320C6713 processor is described as follows in the embodiment underwater acoustic communication set receiving unit: input signal is sent into the input V of MAX153 chip _InBehind the pin, WR/RDY and RD by the square-wave signal of AD9851 chip output frequency 96kHz access MAX153 chip hold to start analog-to-digital conversion, the INT signal of MAX153 chip is sent low level after analog-to-digital conversion finishes, this INT signal links to each other with the GP7/EXINT7 pin of TMS320C6713 chip, be used for triggering the outer interrupt service routine of dsp chip, the data wire ED0-ED7 of DSP is connected with the data wire D0-D7 end of MAX153 chip U1 and inputs the analog-to-digital conversion result.Outer interrupt service routine obtains after the translation data of modulus conversion chip the data of input dsp chip and carries out subsequent treatment in the double buffering mode.

In the generation of embodiment underwater acoustic communication set middle probe signal, frame synchronizing signal generation, band spectrum modulation, convolution, signal framing, set up synchronously, the time step such as anti-preliminary treatment, merging, data decode all in TMS320C6713 digital signal processor (DSP) chip, carry out software programming and realize.

In sum, time-division disclosed by the invention realizes that multichannel underwater acoustic communication set time reversal utilizes transmitting terminal repeat its transmission information signal frame, receiving terminal passage to switch and realizes that multichannel receives the one by one input of signal, thereby greatly reduced the real-time operation amount of multichannel time reversal, so that just can realize utilizing multichannel to improve the underwater acoustic communication set of communication performance time reversal based on single dsp processor chip.

The original position of frame emission form of the present invention is frame synchronizing signal, is used for setting up the data demodulates start time of receiving terminal; Be probe signals after the frame synchronizing signal, be used for obtaining channel multi-path information by transmission; Be information frame after the probe signals, after each raw information code element of obtaining from the information code element input interface is carried out band spectrum modulation, carry out configuration information frame after the process of convolution with probe signals.Signal becomes frame module that frame synchronizing signal, probe signals and information frame are carried out the time domain arrangement according to frame format with sequential and the protection interval set, thereby forms complete signal frame.Anti-when carrying out timesharing multichannel of the present invention, to N unit receiving array, the probe signals in the frame that transmits and information frame all repeat N time in time in order to carry out repeat its transmission.Simultaneously, for fear of frame synchronization, the intersymbol interference that causes between probe and the information frame, at the frame synchronization head, probe and information frame all insert the protection interval.3 yuan take N=3 receive battle array as example, and the signal frame form of same probe and information signal frame repeat its transmission as shown in Figure 3.

The information code element input interface is from information source (host computer or user's input) obtaining information code element.

Frame synchronousing signal generator is for generation of frame synchronizing signal.

The probe signals generator is for generation of probe signals.

The band spectrum modulation module is carried out band spectrum modulation to information code element.

Information code element after convolution module adopts probe signals to band spectrum modulation carries out convolution algorithm to be processed, and forms information frame.

Receiving unit:

Preposition amplification, filter are connected for multichannel reception signal is carried out pre-process with the reception signal end that receiving terminal receives array element.

Channel to channel adapter connects the multi channel signals after the pre-process, is used for switching the signalling channel of input follow-up modulus conversion chip, time reversal processing and data decode.

Synchronization module utilization copy related operation is caught frame synchronizing signal, is used for setting up the anti-start time of processing, decoding when carrying out receive data.

The time anti-preprocessor receive the multi channel signals of exporting one by one from the channel to channel adapter serial, catch probe signals corresponding to each passage, then each passage probe signals is carried out after time reversal carrying out convolution algorithm with the respective channel information frame of follow-up arrival, finish when passive after anti-the processing, send into one by one string and multichannel combiner.

Serial/parallel multichannel combiner receives and carries out when passive after anti-the processing one by one each channel data of serial input, carries out merging after the serial/parallel conversion according to each passage sequential, and is anti-when realizing multichannel.

Data decoder and anti-during to multichannel after the reception signal carry out data decode according to its modulation system, recover initial data.

Basic realization approach of the present invention is transmitting terminal repeat its transmission information frame, the underwater acoustic communication set receiving terminal switches successively from difference reception array element image data by passage after setting up frame synchronization, carry out one by one time anti-processing of each array element receive data, merge at last, thereby real-time operation expense that can be lower is obtained multichannel multipath focusing effect.Consider that in most of underwater acoustic communication set use occasions amount of communication data is little, data transfer rate is lower, the present invention obtains multichannel performance time reversal with lower computing hardware (such as the single-chip digital signal processor chip) and the information frame repeat its transmission cost paid can be born.

In each functional module of this underwater acoustic communication set, pre-process, passage switching, ADC, power amplifier are comprised of hardware circuits such as preposition amplification, filter, modulus conversion chip, channel to channel adapter chip, power amplifiers; The modules such as anti-preliminary treatment during multichannel, serial/parallel multichannel merging, data decode, frame synchronization foundation, band spectrum modulation, convolution, signal framing, frame synchronization generator, probe signals generator are the Digital Signal Processing link, are realized by the dsp chip software programming.

In embodiments of the present invention, the information code element input interface of radiating portion is from information source (host computer or user's input) obtaining information code element, and the information code element that obtains is sent into the spread spectrum adjusting module.The band spectrum modulation module is from information code element input interface obtaining information code element and carry out band spectrum modulation, then the information code element after the band spectrum modulation is sent into convolution module.The probe signals generator is for generation of probe signals, and the probe signals of generation is sent into respectively convolution module and become frame module with signal.Information code element after convolution module adopts probe signals to band spectrum modulation carries out convolution algorithm to be processed, and forms information frame and send into signal to become frame module.Frame synchronousing signal generator is for generation of frame synchronizing signal, and the frame synchronizing signal of generation is sent into signal and become frame module.Signal becomes frame module according to the sequential of signal frame format setting and protection interval the frame synchronizing signal of frame synchronousing signal generator output, the probe signals of probe signals generator output and the information signal frame of convolution module output to be carried out forming complete signal frame after time domain is arranged.And complete signal frame sent into power amplifier.Power amplifier will become the complete signal frame of frame module output to carry out sending into transmitting transducer after the power amplification to carry out underwater sound emission.

The preposition amplification of receiving unit, filter are connected for multichannel reception signal is carried out pre-process with the reception signal end that receiving terminal receives array element; Channel to channel adapter connects the multi channel signals after the pre-process, is used for switching the signalling channel of input follow-up modulus conversion chip, time reversal processing and data decode; Synchronization module utilization copy related operation is caught frame synchronizing signal, is used for setting up the anti-start time of processing, decoding when carrying out receive data; The time anti-preprocessor receive the multi channel signals of exporting one by one from the channel to channel adapter serial, catch probe signals corresponding to each passage, then each passage probe signals is carried out after time reversal carrying out convolution algorithm with the respective channel information frame of follow-up arrival, finish when passive after anti-the processing, send into one by one string and multichannel combiner; Serial/parallel multichannel combiner receives and carries out when passive after anti-the processing one by one each channel data of serial input, carries out merging after the serial/parallel conversion according to each passage sequential, and is anti-when realizing multichannel; Data decoder and anti-during to multichannel after the reception signal carry out data decode according to its modulation system, recover initial data.

The problem to be solved in the present invention is to utilize limited processor hardware resource in underwater acoustic communication set, provide a kind of by transmitting terminal repeat its transmission identical information frame, receiving terminal carries out preliminary treatment time reversal, the merging of timesharing to multi channel signals with the passage switching mode.

Claims (1)

1. a timesharing realizes the multichannel underwater acoustic communication set of time reversal, it is characterized in that being provided with radiating portion and receiving unit;

Described radiating portion is provided with information code element input interface, band spectrum modulation module, convolution module, probe signals generator, frame synchronousing signal generator, signal and becomes frame module, power amplifier and transmitting transducer; Described information code element input interface is connected with the input of band spectrum modulation module, the output of band spectrum modulation module is connected output and is connected with the input of convolution module with the probe signals generator, the input that signal becomes frame module is connected output with the output of the output of convolution module, probe signals generator respectively and is connected with frame synchronousing signal generator, the input of power amplifier, output become the output of frame module to be connected input with transmitting transducer with signal respectively to be connected;

Described receiving unit is provided with array of multi-unit receiving, pre-process module, censor key, A/D converter, synchronization module, time reversal preprocessor, serial/parallel multichannel combiner and data decoder; Described array of multi-unit receiving receives array element by at least 2 and forms, the output of array of multi-unit receiving is connected with the input of pre-process module, multi channel signals output after the processing of pre-process module connects the input of A/D converter through censor key, the output of A/D converter respectively with the input of synchronization module with time reversal preprocessor be connected input and be connected, the frame synchronizing signal output of synchronization module is connected with the frame synchronizing signal input of preprocessor time reversal, time reversal preprocessor each channel data input of finishing the serial/parallel multichannel combiner of anti-processing signals output termination when passive, reception signal output part after anti-during the multichannel of serial/parallel multichannel combiner connects the input of data decoder, carry out data decode by data decoder, recover initial data.

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