LU502127B1 - Real-time Detection Method of Time of Flight of Acoustic - Google Patents

Abstract

The invention comprises an integral timing control unit constructed by hardware description language HDL, an ADC acquisition echo signal unit, a filter unit, a ping-pong storage unit, a peak detection unit, a peak value and address judgment unit, an output peak value and time unit and time domain sampling judgment conditions. The whole time sequence control unit generates ADC acquisition enable signal, wave train detection enable signal, maximum value detection enable signal and maximum value storage enable signal to control the normal operation of the above units in time sequence, so as to realize the whole work flow from echo signal acquisition, storage and real-time detection to the peak value of the final output echo and the corresponding time μs level; The calculation amount is small, the space occupancy rate is low, the working efficiency and measurement accuracy of acoustic wave measurement are improved, and the application range is wide.

Description

DESCRIPTION LU502127 Real-time Detection Method of Time of Flight of Acoustic

TECHNICAL FIELD The invention relates to a real-time detection method of time of flight of acoustic, belonging to the technical field of acoustic ranging and detection.

BACKGROUND The existing acoustic travel time detection methods mainly include: (1) echo signal strength comparison method, which has the disadvantages of low accuracy, easy noise interference and low measurement accuracy, (2) time-frequency analysis methods: including joint denoising algorithm based on FIR filter and wavelet threshold method, wavelet transform, short-time Fourier transform, Wei Gena-Wiley distribution and Hilbert-Huang transform, etc., although all of them can achieve high-precision measurement of the travel time of echo signals, they are computationally expensive and not real-time. In a word, the main problems of the above existing ultrasonic detection methods are: weak real-time detection of ultrasonic echo signals, large amount of calculation and high space occupancy rate.

SUMMARY The purpose of the present invention is to provide a real-time detection method for acoustic travel, which can realize real-time detection of the peak value of acoustic echo and its corresponding travel time, effectively reduce the calculation amount, have low space occupancy rate, improve the working efficiency and measurement accuracy of acoustic ranging, and have a wide application range.

The invention achieves the above-mentioned purpose through the following technical scheme: A real-time detection method of time of flight of acoustic is characterized in that the hardware description language HDL is used to design the whole time sequence control unit, ADC acquisition signal echo signal, filter unit, ping-pong storage unit, peak detection unit, head wave peak value and address judgment unit, output head wave peak value and time, etc., and the time domain sampling judgment condition framework. The overall timing control mainly generates four enabling signals acting on the normal operation of the above units through the system clock, counter and register, namely, ADC collects enabling signals and controls ADC to collect echo signals accurately and in real time; Wave detection enable signal, and control ping-pong storage and peak detection unit to work normally; The maximum detection enable 502 127 signal controls and judges the peak value and time of the echo head wave signal; Save the maximum enable signal, and control the peak-to-peak value and the corresponding time of the first wave of the output echo. The above four enable signals are high-level and effective, and through the overall timing control, the us-level full workflow from the acquisition, conversion, storage and real-time detection of the echo signal to the peak of the final output echo and the corresponding time is realized. The time domain sampling discrimination conditions are: (sampling points-error adjustment parameters) < Ti-Ti-1 < (sampling points+error adjustment parameters) and (sampling points-error adjustment parameters) < Tixi-Ti < (sampling points+error adjustment parameters), Where T is time, in us; 1 is a positive integer >1.

The real-time detection method of time of flight of acoustic is characterized in that when the high level of ADC acquisition enable signal adc flag is valid, the ADC is controlled to acquire echo signals in real time, and the echo data is stored in the buffer RAMO. The echo signal is processed by a filter to eliminate the interference of the noise signal and obtain a smooth echo signal.

The real-time detection method of time of flight of acoustic is characterized in that when the ADC collects echo signals for a preset time, and the wave train detection enable signal detect flag is effective at a high level, the ping-pong storage unit is started to work, and the real-time echo data stream with length N stored in the buffer area RAMO is read into the buffer area RAMI or the buffer area RAM2 of the ping-pong storage unit in sequence in equal time; The ping-pong storage unit is provided with two selectors and a NOT gate. According to the time sequence of the wave train detection enable signal, under the control of the selectors and NOT gates, after the buffer RAMI is full, it is stored in the buffer RAM2, and the data in the buffer RAMI is read out to the peak detection unit, or after the buffer RAM2 is full, it is stored in the buffer RAMI, and the data in the buffer RAM2 is read out to the peak detection unit. The peak detection unit judges and compares the data with the window length n according to the time sequence of the wave train detection enable signal, and starts the address counter count and the offset adjustment counter shift cnt to identify the maximum value of the window length n. If the maximum value is just in the middle of the window length, it registers the maximum value and its address, and executes it alternately in turn until all the data in the ping-pong storage units RAMI and RAM2 are judged and identified. The maximum value and address (address = count

+ shift cnt) satisfying the conditions are registered in the buffer RAM3. LU502127 The real-time detection method of time of flight of acoustic is characterized in that when the maximum detection enable signal max flag 1s valid, the maximum value and its position in the buffer RAM3 are identified by the peak value and address judging unit, and the addresses corresponding to the maximum value in the RAM3 are judged and compared within the range of ADC sampling rate, and the corresponding sampling points are sequentially different by the number of sampling points of a periodic signal; if the time domain sampling discrimination conditions are met: (sampling points-error adjustment parameters) < Ti-Ti-1 < (sampling pointsterror adjustment parameters) and (sampling points-error adjustment parameters) <Ti+1-Ti< (sampling points+error adjustment parameters); Where T is time, in us; 1 is a positive integer >1. The maximum value of the corresponding address is registered, and other data in RAM3 are sequentially compared to obtain the final maximum value max value, and then the address is checked and corrected according to the max value to obtain the time time value corresponding to the final maximum value max value. When the save maximum enable signal save flag is valid, the peak-to-peak value max value and time value of the echo head wave signal are output.

The real-time detection method of time of flight of acoustic is characterized in that the overall timing control is mainly realized by a clock frequency division module and an enabling signal generation module, and ADC acquisition clock, ADC acquisition enabling signal, detection enabling signal, maximum value detection enabling signal and maximum value storage enabling signal are generated. The data storage module includes ADC acquisition echo signal, filter unit and ping-pong storage unit. The input data stream and output data stream of Ping-pong storage unit are controlled by selector and NOT gate, which are continuous without any pause. The seamless buffering of data is completed in real time, and the real-time detection of the echo head wave signal is realized. The real-time peak detection module includes peak detection, peak value and address judgment unit and output peak-to-peak value and time unit.

BRIEF DESCRIPTION OF THE FIGURES Fig. 1 is a block diagram of the overall structure of the present invention; Fig. 2 is a timing control diagram of an enable signal according to the present invention; Fig. 3 is a schematic diagram of the detection process of the present invention; Fig. 4 is an overall control schematic diagram of the present invention;

Fig. 5 is the test result diagram of the present invention. LU502127

DESCRIPTION OF THE INVENTION Ultrasonic testing is widely used in oil wells, so it is very important to detect the specific position of internal defects in oil wells efficiently, in real time and accurately. The existing ultrasonic detection method has the voltage comparison method for processing ultrasonic echo signals, which has the disadvantages of low accuracy, susceptibility to noise interference and low measurement accuracy. There are also several time-frequency analysis methods based on FIR filter and wavelet threshold method, such as joint denoising method, wavelet transform, short-time Fourier transform, Wei Gena-Wiley distribution and Hilbert-Huang transform. Although they can denoise the ultrasonic echo signals and get good echo signals, they are difficult to meet the high standard requirements of real-time, accuracy and rapidity of oil well internal flaw detection due to their large amount of calculation, high space occupancy rate and weak real-time. According to the invention, the hardware description language HDL (Hardware Description Language) can be used to describe the time sequence behavior of hardware systems at different times, and the hardware description language HDL is used to design and build an organic whole structure of an overall time sequence control unit, an ADC acquisition echo signal unit, a filter unit, a ping-pong storage unit, a peak detection unit, a peak-to-peak value and address judgment unit, an output peak-to-peak value and time unit and time domain sampling judgment conditions, and a real-time detection method of time of flight of acoustic is proposed. Compared with the prior art, the method realizes the real-time detection of peak-to-peak value and travel time of sound waves, effectively reduces the calculation amount, has low space occupancy rate, improves sound wave detection efficiency and measurement accuracy, and expands the application range.

The implementation of the real-time detection method of time of flight of acoustic will be further described in detail with reference to the following drawings: (referring to Figures 1-5) The technical solution for realizing the purpose of the invention 1s as follows: a real-time detection method of time of flight of acoustic comprises an overall time sequence control unit, an ADC echo signal acquisition unit, a filter unit, a ping-pong storage unit, a peak detection unit, a peak value and address judgment unit, and an output peak value and time unit. Through the modular design from top to bottom, the real-time detection of the peak value and the corresponding time is realized.

Referring to Fig. 1, which is a block diagram of the overall structure of the present,502127 invention. First, when the ADC acquisition enable signal adc flag is valid, the ADC is controlled to acquire echo signals in real time, and the echo data is stored in the buffer RAMO. The echo signal is processed by a filter to eliminate the interference of other clutter signals and noise signals and obtain a smooth echo signal. When the wave train detection enable signal detect flag is valid, the ping-pong storage unit is started to work, and the real-time echo data stream with length N stored in the buffer area RAMO is read into the data with window length N according to the time sequence, which is sent to the buffer area RAM1 or RAM2 of the ping-pong storage unit through selector and NOT gate control. Meanwhile, the peak detection unit judges and recognizes the maximum value of the data in the buffer area RAMI or RAM2, and executes alternately; The ping-pong storage unit reads while storing, and the input data streams and output data streams at both ends of the ping-pong storage unit continuously and in real time send data to the peak detection unit. At the same time, the address counter count and the offset counter shift cnt are started to jointly calculate the address address of the first echo signal, and the peak detection unit registers all values which meet the maximum values in RAMI and RAM2 in the ping-pong storage unit and are in the middle of the window length N into the buffer RAM3. Through the peak value and address judgment unit, when the maximum value detection enable signal max flag is valid, it is judged and recognized. Within the range of ADC sampling rate, the corresponding sampling points are sequentially different by one cycle signal, and all values in RAM3 are compared and judged. If the time domain sampling judgment conditions are met: (sampling points-error adjustment parameter) < Ti-Ti1 < (sampling points+error adjustment parameter) and (sampling points-error adjustment parameter) < Ti+1-Ti.< (sampling points+error adjustment parameter). Where T is time, in us; i is a positive integer >1; The final maximum max value meeting the conditions is sent to the output peak-to-peak value and time unit; At the same time, the address is checked and corrected according to the obtained max value, and the address time value corresponding to the final maximum max_value is obtained. When the save maximum enable signal save flag is valid, the peak value max value and time time value of the first peak of the echo are output.

Referring to Fig. 2, which is a timing control diagram of an enable signal according to the present invention; The whole timing control unit completes the whole timing control through the system clock sys clk, counters and registers, and generates ADC acquisition enable signal adc flag, train detection enable signal detect flag, maximum value detection enable signal 502 127 max flag and maximum value storage enable signal save flag respectively. Control ADC echo signal acquisition unit, ping-pong storage unit, peak detection unit, peak value and address judgment unit and output peak-to-peak value and time unit to work normally.

Referring to Fig. 3, which is a schematic diagram of the detection process of the present invention. It mainly collects the data stored in the buffer RAMO by ADC in real time, and sequentially reads the data in the buffer RAMI of the ping-pong storage unit with window length N according to the time sequence. At the same time, it judges and recognizes the maximum value of the data in the buffer RAM2, and executes it alternately.

In order to explain in detail the detection principle of a real-time detection method of time of flight of acoustic of the present invention, the window length n=10 and the dotted line box a in Fig. 3 are taken as examples for explanation; The length of buffer RAMO is n. According to the timing requirements, read 10 data corresponding to addresses 2-11 in buffer RAMO into buffer RAMI or RAM2, and then judge whether the maximum value of these 10 data is in the middle of the dotted line box, that is, at address 6. If the conditions are met, the value 14893 corresponding to address 6 will be registered; otherwise, it will not be registered. Circulate in turn until all the values satisfying the conditions are registered in the buffer RAM3, then judge and compare the values in the buffer RAM3 in turn within the range of ADC sampling rate, and finally get that 16383 is the peak-to-peak value of the echo head wave signal, and the corresponding time is 12; At this point, the whole detection process is completed.

In the same way, taking window length n=11 as an example, the length of buffer RAMO is n. According to the timing requirements, read 11 data corresponding to addresses 3-13 in buffer RAMO into buffer RAMI or RAM2, and then judge whether the maximum value of 11 data corresponding to 11 addresses 3-13 is in the middle of dotted box b (see Fig. 3), that is, address 8. If the conditions are met, the address will be corresponding. Otherwise, do not register. Circulate in turn until all the values satisfying the conditions are registered in the buffer RAM3, and sequentially judge and compare the values in the buffer RAM3 by the peak value and address judging unit, so that the final maximum value is the peak-to-peak value of the echo head wave and the corresponding time. Here, only one set of data is selected for explanation, and the principle of the whole detection method of the invention is the same. From the identification result of the peak and moment of the output echo to the end of the acquisition of the echo signal unit by ADC, the time interval of the whole cycle reaches us level. LU502127 Referring to Fig. 4, which 1s the overall control schematic diagram of the present invention. The hardware description language HDL is used for top-down modular design, including clock frequency division module, enabling signal generation module, data storage module and peak real-time detection module. The overall timing control unit comprises a clock frequency division module and an enabling signal generation module; the ADC signal acquisition unit, the filter unit and the ping-pong storage unit are respectively provided with a data storage module; and the peak detection unit, the peak value and address judgment unit and the output peak value and time unit are respectively provided with a peak real-time detection module.

Among them, the clock frequency division module mainly divides the system clock to generate the ADC acquisition clock adc clk required by the ADC acquisition echo signal unit; The main function of the enable signal generation module is to generate ADC acquisition enable signal adc flag, detection enable signal detect flag, maximum value detection enable signal max flag and maximum value storage enable signal save flag; Which is use for controlling that normal work of each unit of the real-time detection method of time of flight of acoustic; The data storage module is mainly used for storing the real-time data and filtering processing of the ADC acquisition signal unit; The main function of the real-time peak detection module is to process all the data in the data storage module according to the ping-pong storage unit under the control of the overall timing control unit system, identify the peak value of the echo head wave through the peak detection and peak value and address judgment unit, and finally get the final maximum value and its position, which is the peak value and time of the echo head wave signal.

The overall timing control unit is mainly composed of a clock frequency division module and an enabling signal generation module, which generates ADC acquisition clock adc clk, ADC acquisition enabling signal adc flag, train detection enabling signal detect flag, maximum value detection enabling signal max flag and maximum value storage enabling signal save flag, and the working voltages are all 3.3V.

In Fig. 4, the input signals are: sys clk is the system clock, sys rst n is the system reset signal, syn is the synchronization signal, fre select is the ADC sampling frequency selection signal, the low level O indicates sampling frequency 1, the high level 1 indicates sampling frequency 2, and the relationship between sampling frequency 1 and sampling frequency 2 is: sampling frequency 2 = 2* sampling frequency 1; Data in[M:0] means that the input m bits of data with certain noise. LU502127 The output signals are: the clock signal adc clk that ADC collects data; The maximum value max _ value [M: 0] of M bits is output; Time value[L:0] indicates the corresponding L-bit address when the maximum value is output; K represents the address bits of data in RAM. Among them, M, L and K can be adjusted according to the actual situation.

The invention relates to a real-time detection method of time of flight of acoustic, which comprises that follow detection steps: Step 1, completing the overall time sequence control of a real-time detection method of time of flight of acoustic through a system clock, a counter and a register to obtain four enabling signals, namely ADC acquisition enabling signal adc flag, detection enabling signal detect flag, maximum value detection enabling signal max flag and maximum value storage enabling signal save flag; Step 2, fre select controls the sampling frequency of ADC, ADC acquisition enable signal adc _flag controls ADC to collect echo signals in real time, and the echo signals are processed by a filter to eliminate the interference of other clutter signals and noise signals, so as to obtain smooth echo signals; Step3, after the data collected by ADC is stored in the buffer RAMO for a preset time, when the wave train detection enable signal detect flag is at a high level, the ping-pong storage unit is started for ping-pong operation. Under the control of selector and NOT gate, the data stream in the buffer RAMO is read into the ping-pong buffer RAM1 or RAM2 with data with window length n according to the time sequence of the wave train detection enable signal. When the data stream is stored in RAMI, the data of RAM2 is read out to the window peak detection unit, and obtain the maximum value of the ping-pong memory, which is the window length n of the data storage module; Step 4, judging whether the maximum value in the ping-pong memory is in the middle of the window length n, registering the maximum value satisfying the conditions and its corresponding address in the buffer RAM3, and sending it to the peak value and address judging unit; Step 5, starting the address counter count and the offset counter shift cnt to jointly calculate the address of the first echo signal, judging the maximum value and its position in the buffer RAM3 by the peak value and address judging unit, and identifying whether the maximum value and the corresponding time in the acquisition queue are the peak value of the periodic signal, and, 502127 the sampling points corresponding to the maximum peak value are sequentially different by one sampling point of the periodic signal; When the maximum detection enable signal max flag 1s active at high level, and the time domain sampling discrimination conditions are met: (sampling points-error adjustment parameters) < Ti-Ti-1 < (sampling points+error adjustment parameters) and (sampling points-error adjustment parameters) < Ti+1-Ti < (sampling points+error adjustment parameters); Where t is time, in us; i is a positive integer >1; The maximum value of the corresponding time is registered, Step 6, sequentially comparing the maximum values satisfying the conditions in step 5, and checking and correcting the address according to the obtained max value value to obtain the address time value corresponding to the final max value. When it is detected that the save flag enable signal with the maximum value is at the high level, the peak-to-peak value max value and time value of the first echo wave are output.

Referring to Fig. 5, which is a diagram of the detection result of a real-time detection method of time of flight of acoustic according to the present invention, wherein: sys_clk is the system clock; sys rst n is the system reset signal, which is active at low level; fre select is the ADC sampling frequency selection signal, and the sampling frequency is designed and selected according to the actual requirements; syn is synchronous signal, 0 is asynchronous and 1 is synchronous; data in is the input data with certain noise; adc flag is the ADC acquisition enable signal, and when it is at high level, the ADC acquisition signal unit starts to collect data; detect flag is the detection enable signal, and when it is at a high level, it starts to detect the data in the buffer RAM1 or RAM2; max flag is the maximum value detection enable signal, and the maximum value is detected when it is at high level; save flag is an enable signal for saving the maximum value, and when it is at a high level, the detected maximum value is saved; adc clk is the clock signal that ADC collects data; max value is the peak value of the output after detection; time value is the corresponding address when the peak-to-peak value is output.

As shown in Fig. 5, the left side of Fig. 5 shows all the input and output signals, and the bottom of Fig. 5 shows the time scale in us; fre select is low level, indicating that the ADC sampling frequency selects sampling frequency 1; Syn is low, indicating synchronization. data in is the first wave data of the input ultrasonic echo. adc flag is set to high level at 10us,

and ADC starts to collect data and store it in the buffer RAMO. After 40us, detect flag is set 19502127 high level, and ping-pong storage unit and peak detection unit are controlled to start detection. Then, when detect flag is high level, monopulse noise interference signal is added. (This is because no matter in the technical field of acoustic measurement or in the aspect of ultrasonic logging, although the echo signal is processed, there will inevitably be interference from other noise signals. When the train detection enable signal detect flag is at a high level, a single pulse noise interference signal is added, so as to detect and verify whether the method of the invention can realize accurate detection when there are noise interference signals). As shown in Fig. 5, at 300us, the maximum value detection enable signal max flag becomes high level, indicating that the maximum value is detected. When the maximum value storage enable signal save flag is high level, the maximum value and its address are stored. It takes 300us-50us=250us to start the detection when the train detection enable signal detect flag is high, and to output the peak value when the save enable signal save flag is high, which indicates that the method of the invention realizes fast and efficient real-time detection.

As shown in Fig. 5, the peak-to-peak value of the input echo head wave data data in is 16383, and the address is 114. Under the condition of noise interference signal, the peak-to-peak value and time of the actual input signal can still be accurately detected by the real-time detection method of time of flight of acoustic of the present invention. The real-time detection method of time of flight of acoustic of the invention is applied to actual detection, so as to realize accurate and real-time detection of the peak value of the echo head wave signal and its corresponding time, and make a contribution to acoustic ranging and oil well internal flaw detection.

The above are only preferred embodiments of the present invention, and the above examples do not restrict the substance of the present invention in any form. Any simple modifications or variations made by ordinary technicians in the technical field according to the technical substance of the present invention after reading this specification, as well as equivalent embodiments that may be changed or modified into equivalent changes by using the technical content disclosed above, are still within the scope of the technical scheme of the present invention, without departing from the essence and scope of the present invention.

Claims (8)

CLAIMS LU502127

1. A real-time detection method of time of flight of acoustic is characterized in that the hardware description language HDL is used to design the whole time sequence control unit, ADC acquisition signal echo signal, filter unit, ping-pong storage unit, peak detection unit, head wave peak value and address judgment unit, output head wave peak value and time, etc., and the time domain sampling judgment condition framework; the overall timing control mainly generates four enabling signals acting on the normal operation of the above units through the system clock, counter and register, namely, ADC collects enabling signals and controls ADC to collect echo signals accurately and in real time, wave detection enable signal, and control ping-pong storage and peak detection unit to work normally; the maximum detection enable signal controls and judges the peak value and time of the echo head wave signal; save the maximum enable signal, and control the peak-to-peak value and the corresponding time of the first wave of the output echo; the above four enable signals are high-level and effective, and through the overall timing control, the ps-level full workflow from the acquisition, conversion, storage and real-time detection of the echo signal to the peak of the final output echo and the corresponding time is realized; the time domain sampling discrimination conditions are: (sampling points-error adjustment parameters) < Ti-Ti-1 < (sampling points+error adjustment parameters) and (sampling points-error adjustment parameters) < Tixi-Ti < (sampling points+error adjustment parameters); where T is time, in us; 1 is a positive integer >1.

2. The real-time detection method of time of flight of acoustic according to claim 1 is characterized in that when the high level of ADC acquisition enable signal adc flag is valid, the ADC is controlled to acquire echo signals in real time, and the echo data is stored in the buffer RAMO; the echo signal is processed by a filter to eliminate the interference of the noise signal and obtain a smooth echo signal.

3. The real-time detection method of time of flight of acoustic according to claim 1 is characterized in that when the ADC collects echo signals for a preset time, and the wave train detection enable signal detect flag is effective at a high level, the ping-pong storage unit is started to work, and the real-time echo data stream with length N stored in the buffer area RAMO is read into the buffer area RAMI or the buffer area RAM2 of the ping-pong storage unit in sequence in equal time; the ping-pong storage unit is provided with two selectors and a NOT gate; according to the time sequence of the wave train detection enable signal, under the control of the selectors and NOT gates, after the buffer RAMI is full, it is stored in the buffer RAMP 502 127 and the data in the buffer RAMI is read out to the peak detection unit, or after the buffer RAM2 is full, it is stored in the buffer RAMI, and the data in the buffer RAM2 is read out to the peak detection unit; the peak detection unit judges and compares the data with the window length n according to the time sequence of the wave train detection enable signal, and starts the address counter count and the offset adjustment counter shift cnt to identify the maximum value of the window length n; if the maximum value is just in the middle of the window length, it registers the maximum value and its address, and executes it alternately in turn until all the data in the ping-pong storage units RAM1 and RAM2 are judged and identified; the maximum value and address satisfying the conditions are registered in the buffer RAM3.

4. The real-time detection method of time of flight of acoustic is characterized in that when the maximum detection enable signal max flag is valid, the maximum value and its position in the buffer RAM3 are identified by the peak value and address judging unit, and the addresses corresponding to the maximum value in the RAM3 are judged and compared within the range of ADC sampling rate, and the corresponding sampling points are sequentially different by the number of sampling points of a periodic signal; if the time-domain sampling discrimination condition is met, the maximum value at the corresponding time meeting the time-domain sampling discrimination condition is registered in the buffer RAM3, and the final maximum value is obtained by sequential comparison; the final maximum value is the peak value max_value of the first echo peak; check and correct the address address according to the max value value, and get the time time value corresponding to the final maximum max value; when the save maximum enable signal save flag is at high level, the peak-to-peak value max value and time value of the first echo wave are output.

5. The real-time detection method of time of flight of acoustic according to claim 1 is characterized in that the overall timing control unit is mainly composed of a clock frequency division module and an enabling signal generation module, which generates ADC acquisition clock adc clk, ADC acquisition enabling signal adc flag, train detection enabling signal detect flag, maximum value detection enabling signal max flag and maximum value storage enabling signal save flag, and the working voltages are all 3.3V.

6. The real-time detection method of time of flight of acoustic according to claim 1 is characterized in that the ADC signal acquisition unit, the filter unit and the ping-pong operation unit are respectively provided with data storage modules. LU502127

7. The real-time detection method of time of flight of acoustic according to claim 1 is characterized in that the input data stream and the output data stream of the ping-pong storage unit are continuous without any pause, so that the seamless buffering of data is completed, and the real-time measurement of acoustic ranging is realized.

8. The real-time detection method of time of flight of acoustic according to claim 1 is characterized in that the peak detection unit, the peak value and address judgment unit and the output peak value and time unit are respectively provided with a peak real-time detection module.