CN115173864A - Digital acquisition method for large dynamic range transient pulse - Google Patents

Abstract

The invention relates to a high-speed signal acquisition method, in particular to a digital acquisition method of a large-dynamic-range transient pulse, which solves the technical problem that the transient pulse with large amplitude span and large measuring range uncertainty is difficult to record in the prior art. The digital acquisition method of the transient pulse with the large dynamic range comprises the following steps of 1: establishing a digital acquisition system of the transient pulse with a large dynamic range; the digital acquisition system of the large dynamic range transient pulse comprises an analog signal processing unit and a waveform digitizing unit; and 2, step: pre-calibrating a digital acquisition system of the transient pulse with a large dynamic range by using a standard signal; and 3, step 3: inputting the transient pulse P1 into the digital acquisition system of the large dynamic range transient pulse pre-calibrated in the step 2, acquiring waveform data of the pulse train P2, acquiring and extracting different gain waveforms of the waveform data, and realizing digital acquisition of the large dynamic range transient pulse.

Description

A Digital Acquisition Method of Transient Pulse with Large Dynamic Range

technical field

The invention relates to a high-speed signal acquisition method, in particular to a digital acquisition method of transient pulses with a large dynamic range.

Background technique

Transient pulse signal measurement has a wide range of needs in cutting-edge scientific research, such as high-energy physics, radiation detection, and detonation experiments. The occurrence process of these physical experiments is extremely short, and their physical detection signals are characterized by transient nature, usually manifesting as a single fast pulse signal of nanosecond to microsecond level; and have the characteristics of large amplitude span and large range uncertainty, which may The amplitude of the signal ranges from a few millivolts to several hundred volts; at the same time, it is also non-periodic and difficult to repeat once, which brings great difficulty to the accurate acquisition of the back-end acquisition and recording system.

At present, the range coverage method is often used for the acquisition of single transient pulses with large amplitude span and large range uncertainty. The acquisition channel is acquired by means of range overlap, and by setting different gains, these channels cover different ranges of the fast pulse signal respectively. Although this acquisition method can realize the acquisition of fast pulse signals, it still has the problem of inconsistency processing due to differences in synchronous triggering, biasing, conditioning circuits, and analog-to-digital converters between different channels.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the technical problem that it is difficult to record transient pulses with large amplitude span and large range uncertainty in the prior art, and provide a digital acquisition method of transient pulses with large dynamic range, which can realize the large dynamic range of transient pulses. Dynamic range acquisition.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is:

A digital acquisition method for transient pulses with a large dynamic range, which is special in that it includes the following steps:

Step 1: establish a digital acquisition system for transient pulses with a large dynamic range; the digital acquisition system for transient pulses with a large dynamic range includes an analog signal processing unit and a waveform digitizing unit; the analog signal processing unit is used to divide the transient pulse into N-channel signals, respectively perform signal attenuation and signal delay on the N-channel signals, and then composite the N-channel signals after the signal delay to generate N phase-separated pulse trains; the waveform digitizing unit is used to convert the pulse trains into waveforms data; N is a positive integer greater than 1;

Step 2: use the standard signal to pre-calibrate the digital acquisition system of the large dynamic range transient pulse in step 1;

Step 3: Collection and Extraction

Input the transient pulse P1 to be measured into the digital acquisition system of the pre-calibrated large dynamic range transient pulse, obtain the waveform data of the pulse train P2, and collect and extract the different gain waveforms of the waveform data to realize the large dynamic range transient pulse. Digital collection.

Further, in step 1, the analog signal processing unit includes N branches and a signal compound, wherein N is a positive integer;

Each branch includes sequentially connected signal branches, signal attenuation and signal delay;

The input ends of the N signal branches are connected to the transient pulse, and are used to divide the transient pulse into N outputs;

The signal attenuation is used to adjust the gain of the output of the signal branch and output the attenuation pulse;

The signal delay is used to add signal delay time to the attenuation signal, and output phase separation pulses, thereby obtaining N phase separation pulses corresponding to N branches;

The signal compounding is used to compound the N phase separated pulses into a pulse train for output; the output end of the signal compounding is connected to the input end of the waveform digitizing unit.

Further, step 2 is specifically:

2.1) Calibrate the vertical sensitivity of N shunts

2.1.1. Generate a standard square wave pulse signal with an amplitude of V ₀ ;

2.1.2. The standard square wave pulse signal is equally divided into two outputs, one output is connected to the external trigger channel TRIG of the waveform digitizing unit; the other output is connected to the signal channel CH of the digital acquisition system for large dynamic range transient pulses , obtain the pulse train waveform data corresponding to the N branches;

2.1.3. Perform analog-to-digital conversion on the N pulse amplitudes in the pulse train waveform data obtained in step 2.1.2 to obtain quantized values CODE ₁ , CODE ₂ , ..., CODE _N ;

2.1.4. According to the standard square wave pulse signal amplitude _{V 0} and the quantized values _{CODE 1} , _{CODE 2} , .

2.2) Calibrate the delay time Δt _D0 , . . . , Δt _D(N-1) corresponding to the N branches.

Further, step 3 is specifically:

3.1) The transient pulse P1 inputs the large dynamic range transient pulse digital acquisition system to obtain the waveform data of the pulse train P2;

3.2) _Use the vertical sensitivities A ₁ , . The position sequence in the waveform, y represents the actual quantization value corresponding to this point, then the amplitude value of this point is yA _X ; 1≤x≤N;

Define the point at which the pulse train P2 begins to appear as the starting point of the output pulse waveform of the first branch, and calculate the waveform of the pulse train P2 by using the delay time Δt _D0 , ..., Δt _D(N-1) calibrated in step 2.2). The window time corresponding to each branch corresponding to the data can obtain corresponding N different gain waveforms, and realize the digital acquisition of large dynamic range transient pulses.

Further, in step 2.1.4, the calculation of the vertical sensitivity of the N branches is specifically:

Assuming that the quantization bits of the analog-to-digital conversion are M bits, then the vertical sensitivity of the nth branch is A _n

The upper range limit B _n of the nth branch is:

Further, in step 2.1.2, the specific method for obtaining the pulse train waveform data corresponding to the N branches is:

By adjusting the amplitude V ₀ of the standard square wave pulse signal, the pulse train waveform data corresponding to the N branches is obtained.

Further, step 3.1) is specifically:

3.1.1. Use signal branching to divide the input transient pulse P1 into N signals;

3.1.2. Perform gain adjustment on the gains of the N-channel signals in step 3.1.1 to obtain N-channel attenuation pulses;

3.1.3. Add signal delay time T _D1 ... T _DN to each channel of attenuation signal in step 3.1.2 to obtain N channels of phase separation pulses;

3.1.4. Combine the N-channel phase separation pulses in step 3.1.3 to obtain a pulse train P2;

3.1.5. Use the waveform digitizing unit to convert the pulse train P2 into waveform data.

Further, the value of N is 3.

Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

1. The present invention performs signal splitting, signal attenuation and signal delay on transient pulses before waveform digitization, and then performs signal recombination to generate pulse trains including N phase separations, and then uses waveform digitizing units to form pulses. The waveform can be digitized directly by the series, so that the waveform digitizing instrument (analog-to-digital converter ADC) can sample the transient pulse N times, and the N sampling process can be realized by using a single channel, so that the large dynamic range acquisition of the transient pulse can be realized. .

2. The present invention can sample the transient pulse N times, and the N times sampling process can be realized by using a single channel. At the same time, the gain of the N branched pulses can be adjusted according to the range coverage requirements, so that the transient pulse can be realized. Large dynamic range acquisition, and can meet the recording requirements of transient pulses with large amplitude span and large range uncertainty.

3. The present invention utilizes a single analog-to-digital conversion device ADC in the waveform digitizing unit to sample the transient pulse multiple times, which can double the scale of the acquisition system.

4. The present invention can use the same analog-to-digital conversion device ADC in the waveform digitizing unit to sample the transient pulse multiple times, and use the same waveform digitizing circuit (waveform digitizing unit) to implement, with the same RF drive, clock synchronization, and offset adjustment. , storage, trigger unit and other circuits can avoid the channel difference introduced by multi-channel parallel sampling.

Description of drawings

FIG. 1 is a flow chart of a method for digitally collecting transient pulses with a large dynamic range according to the present invention.

FIG. 2 is a schematic diagram of a circuit of three equal divisions in an embodiment of the present invention.

FIG. 3 is a schematic diagram of a π-shaped resistance attenuation network in an embodiment of the present invention.

FIG. 4 is a schematic diagram of an integrated delay line device in an embodiment of the present invention.

FIG. 5 is a schematic diagram of a signal compounding method based on an adder in an embodiment of the present invention.

FIG. 6 is a block diagram of a waveform digitizing unit in an embodiment of the present invention.

FIG. 7 is a schematic diagram of a transient pulse P1 in an embodiment of the present invention.

FIG. 8 is a schematic diagram of a pulse train P2 in an embodiment of the present invention.

9 is a schematic diagram of waveform timing in an embodiment of the present invention; wherein Trig: external trigger signal, P1: fast pulse to be measured, P2: pulse train, I1: first branch attenuation pulse (phase separation pulse), I2: second branch delay pulse, I3: delay pulse of the third branch, _tw : complete duration of a single pulse, △t _D1 : delay time of I2 compared to I1, △t _D2 : delay time of I3 compared to I1, W1: the first delay time A waveform window, W2: second waveform window 2, A1: vertical sensitivity of the first waveform window, A2: vertical sensitivity of the second waveform window, A3: vertical sensitivity of the third waveform window, T0: waveform trigger point.

FIG. 10 is a schematic diagram of the principle of pre-calibration in an embodiment of the present invention.

Detailed ways

The invention provides a digital acquisition method of large dynamic range transient pulse. The specific implementation method of the present invention will be further described in detail below with reference to the accompanying drawings.

Step 1: Establish a digital acquisition system for large dynamic range transient pulses

As shown in Figure 1, the digital acquisition system of large dynamic range transient pulse can be divided into two parts: analog signal processing unit and waveform digitizing unit.

The main purpose of the analog signal processing unit is to generate and process the pulse train for the input signal, and output a pulse train including N transient pulses. Each pulse in the pulse train has the same waveform as the transient pulse. Copy, but the amplitude of each pulse in the pulse train P2 is different, which can be adjusted according to the detection range coverage requirement. In addition, the N transient pulses in the generated pulse train are separated in phase, and N is a positive integer greater than 1;

The waveform digitizing unit inputs the output pulse train of the analog signal processing unit into the digital waveform acquisition instrument (analog-to-digital conversion device ADC), and mainly realizes waveform digitization functions such as analog signal conditioning, analog-to-digital conversion, synchronous timing, data storage, and data transmission; The waveform digitizing unit is used to convert the pulse train into waveform data;

The analog signal processing unit Q1 mainly includes four processes: signal branching, signal attenuation, signal delay, and signal compounding. The main purpose of the analog signal processing unit is to generate N pulse trains P2 which are separated in phase and different in amplitude for the input signal (transient pulse P1 ), see FIG. 8 .

1.1) Signal branching refers to dividing the input signal (transient pulse P1) into N outputs, which can be realized by using a special chip or a discrete resistor network after research. Discrete resistor networks can be bisected or unequally divided. Special chips such as SSM's surface-mount power dividers include PS1608G, PS2012G, PS3216G and other models. The maximum bandwidth is DC-20GHz, and it has the advantages of small size, low distortion, and low reflection.

In this embodiment, a three-division circuit based on a discrete resistance network is adopted, where N=3, as shown in Figure 2; the three-division circuit is composed of resistor R1, resistor R2, resistor R3, and resistor R4, and R1=R2=R3 =R4=24.9Ω, the input impedance and output impedance of the three-section circuit are both 50Ω, one end of the resistor R1 is used as the input of the signal branch in step 1.1), and is connected with the input signal (transient pulse P1), the other end of the resistor R1 is connected to the input signal (transient pulse P1). One end is connected to one end of resistor R2, resistor R3 and resistor R4 respectively. The other end of resistor R2, resistor R3 and resistor R4 is used as shunt output, which is N-way output of signal shunt, N-way output and attenuation N-way input (input terminal for signal attenuation).

1.2) Signal attenuation refers to the independent adjustment of the gain (amplitude) of the shunt signal, which can be achieved by adding an attenuation circuit.

Corresponding to the N-channel output of the signal branch in step 1.1), the signal attenuation includes a total of N-channel attenuation circuits, and each attenuation circuit can be implemented by an integrated attenuator or a discrete resistance network. The integrated attenuator can be directly welded on the circuit board, and has the advantages of small size, high precision and high reliability; the discrete resistor network has the characteristics of flexible adjustment. In this embodiment, a discrete resistor network is preferred.

As shown in Figure 3, it is a π-shaped attenuation network composed of discrete resistors, forming a one-way attenuation circuit. As can be seen from Figure 3, one end of the resistor R5 and the resistor R6 is grounded, and the other ends of the resistor R5 and the resistor R6 are connected to the two ends of the resistor R7 respectively. The one end of the resistor R7 and R5 can be used as the signal input terminal VIN. The resistor R7 The terminal connected to the resistor R6 can be used as the signal output terminal Vout. Different attenuation times can be determined by adjusting the resistance values of the resistor R5, the resistor R6 and the resistor R7. For example, when the attenuation value of the resistor network is 20dB, R4=24.7Ω, R5=R6=61.1Ω. In this embodiment, the resistor R5, the resistor R6 and the resistor R7 are preferably 0.1% high-precision thick-film high-frequency resistors. Other N-1 attenuation circuits are similar to Figure 3. Therefore, the signal attenuation is composed of N channels of attenuation circuits, with a total of N channels of signal input and N channels of signal output. Connect to the N input of the signal delay.

1.3) Signal delay refers to adding a signal delay time (t _D1 to t _DN ) for each signal, and an integrated SMD analog delay line device can be used.

The N-way input in step 1.3) corresponds to the N-way output of signal attenuation in step 1.2. The signal delay includes a total of N-way delay circuits, and the signal delay time of each branch is t _Dn (n is the nth branch, N≥n≥ 1), determined by the complete duration _tw of the input signal (transient pulse P1). _tw is the onset point where the signal begins to appear and the time it takes for the pulse train to completely disappear into the substrate. In order to ensure that each branch pulse is separated in phase, it is required that t _Dn ≥(n-1)×t _w , and t _Dn -t _D(n-1) ≥ t _w . An integrated patch analog delay line device can be used to construct a delay circuit, see Fig. 4 for details, which is an analog delay line device (integrated delay line device) circuit, and the pin IN in Fig. 4 is the input terminal VIN of the analog delay line device, The front end is respectively connected to Rin and input resistance R, R=50Ω, pins T1-T20 are different output terminals of the analog delay line device, T1-T20 represent the output of different delay time, the delay time gradually reaches the analog delay line device through T1 to T20 maximum delay time. To achieve signal matching, a resistor Rout is connected between the signal output end Vout of the analog delay line device and the ground, where Rin=Rout=Z _line , and Z _line is the impedance of the analog delay line device. Preferably in this embodiment, Z _line =50Ω. The signal delay is composed of N-way delay circuits, which can be constructed by N analog delay line devices respectively. There are N-way signal inputs and N-way signal outputs in total. The input of the N-way delay circuit is connected to the N-way output of signal attenuation in step 1.2). , the output of the N-way delay circuit is connected to the input of the signal composite.

1.4) Signal compounding refers to compounding N phase-separated pulses into a pulse train P2, the output of which is connected to the input end of the waveform digitizing unit. In this embodiment, the signal compounding is based on the principle of an adding circuit, and multiple pulses are compounded to form a pulse train P2.

The signal compounding circuit is connected to the subsequent waveform digitizing unit. The waveform digitizing unit is shown in Figure 6, including RF driver, analog-to-digital conversion, processor, etc. As shown in Figure 5, the signal compounding circuit can be formed with the differential amplifier at the input end of the RF driver The summing circuit, the differential amplifier operates in a DC-coupled, single-ended input mode. Vocm is the input common mode voltage, R _g1 and R _g2 are the gain resistors of the differential amplifier, R _f1 and R _f2 are the feedback resistors of the differential amplifier, R _T1 and R _T2 are the termination resistors of the differential amplifier, and RinL is the balance resistor. In order to obtain the best performance of the RF driver, it is necessary to make input balance, transmission line termination matching, and feedback coefficient matching, so R _g1 =R _g2 , R _f1 =R _f2 , R _T1 =R _T2 , RinL=50Ω. In Figure 5, R linen (n is the nth branch, _N≥n≥1 ) is the output impedance of the nth branch of the signal delay circuit in step 1.3), and R _Cn is the matching compensation resistor on the nth signal composite link , one end of R _Cn is connected to the nth branch output of the signal delay, and the other ends of R _C1 to R _CN are connected together as the output end of the signal composite circuit, and are connected to the non-inverting input of the front-end RF drive in the waveform digitizing unit, refer to the accompanying drawings 5. The resistance value of R _Cn can be determined in the following ways: In order to balance the input, match the transmission line termination (the signal resistance is 50Ω matched), and reduce the signal noise, make (R _line1 +R _C1 )//(R _line2 +R _C2 )//… //(R _linen +R _Cn )//…//(R _lineN +R _CN )=50Ω, R _C1 =R _C2 =…=R _Cn =…=R _CN , therefore, after the R _linen value is determined, you can Calculate the resistance of R _Cn .

1.5) The waveform digitizing unit Q2 in Figure 1 inputs the output pulse train P2 of the analog signal processing unit into the digitized waveform acquisition instrument, and mainly realizes waveform digitization functions such as analog signal conditioning, analog-to-digital conversion, synchronous timing, data storage, and data transmission; The waveform digitization is directly performed on the pulse train P2 formed by the processing in step 1.4).

As shown in Figure 6, the waveform digitizing instrument using conventional architecture is implemented, such as ADC+FPGA waveform digitizing architecture, which mainly includes RF driver, analog-to-digital converter ADC, control processor, clock synchronization, offset adjustment, storage, trigger unit, Functional units such as the host computer interface. This embodiment is mainly aimed at the application of the transient pulse P1. Therefore, an analog-to-digital converter ADC with a speed above GSPS is preferred; in addition, in order to meet the needs of the output data processing of the analog-to-digital converter ADC, a high-performance programmable logic device FPGA above 28 nm can be selected. As the core processor to realize data processing and synchronization control functions; in order to reduce noise interference, a differential amplifier with CMRR with high common mode rejection ratio is preferred as the RF driver; in order to extend the bandwidth to DC, DC coupling and single-ended input are preferred as the input The connection between the signal and the RF driver.

Step 2: Use the standard signal to pre-calibrate the digital acquisition system of the large dynamic range transient pulse in Step 1

Based on the digital acquisition system of large dynamic range transient pulses established in step 1, before applying the present invention to implement step 3 to acquire transient pulses, it is necessary to pre-calibrate the amplitude and time relationship of the digital acquisition system of large dynamic range transient pulses . The main purpose is to pre-calibrate the vertical sensitivity and delay time of the pulse waveform corresponding to the N branches of the analog signal processing unit.

As shown in Figure 10, it is a schematic diagram of a pre-calibration connection method; the signal source is used to output a standard square wave for pre-calibration. First, an external signal source can be used to output a square wave pulse signal (standard signal) with an amplitude of pulse V ₀ ; then the square wave pulse signal can be equally divided into two outputs by using a halving power divider; the halving power distribution One output of the device is connected to the external trigger channel TRIG of the waveform digitizing unit, and the other is connected to the signal channel CH of the digital acquisition system of the large dynamic range transient pulse; Set the pulse train waveform data corresponding to the N branches. Since the pulse attenuation of the N branches is different, the amplitude of the pulse V ₀ output by the signal source can be adjusted, so that all the pulses on the pulse train are in the analog-to-digital converter ADC. Within the full-scale range of , read out the ADC quantization values CODE ₁ , CODE ₂ , ..., CODE _n , ..., CODE _N (n is the nth branch, n≥1) corresponding to the N pulse amplitudes, and set The number of quantization bits of the analog-to-digital converter ADC is M bits, then the vertical sensitivity An of the _nth branch is:

The upper range limit B _n of the nth branch is:

Then, select the same waveform feature point (for example, the half-height value of the square wave) on the pulse train, and read the time of the same waveform feature point of each square wave on the pulse train. Let Δt _D(n-1) be The delay time of the nth branch compared to the first branch is equal to the time difference between the nth square wave and the first square wave at the same waveform characteristic point, see FIG. 9 .

Step 3: Collect and extract the input transient pulse to achieve the acquisition of the transient pulse with a large dynamic range

For the large dynamic range transient pulse digital acquisition system established in step 1, input the transient pulse P1, and obtain the pulse train P2 of the transient pulse P1. The waveform data of the pulse train P2 is collected and stored by the host computer, and the acquisition software in the host computer Extract the sampling results of N transient pulses from the digitized waveform data, and obtain sampling waveforms of different ranges according to the vertical sensitivity and delay time calibrated in step 2. This step mainly includes two steps: waveform acquisition and waveform extraction. details as follows:

(1) Waveform acquisition

Input the transient pulse to the analog signal processing unit to obtain the pulse train of the transient pulse; use the waveform digitizing unit to perform analog-to-digital conversion on the pulse train, and obtain a set of pulse train waveform data. covers the entire burst.

(2) Waveform extraction

Waveform extraction mainly extracts each branch pulse from the waveform of the pulse train, and saves multiple pulse waveforms according to the pre-calibrated vertical sensitivity _AN and delay time Δt _D(n-1) of the N branches.

The vertical sensitivity A _N calculates the amplitude value of the pulse train P2 waveform data; set the position of a certain point on the pulse train P2 waveform as (x, y), where x represents the position sequence of the point in the waveform, and y represents the analog-to-digital conversion of the point. If the quantization value of the ADC ADC is used, the amplitude value at this point is yA _x ; N≥x≥1.

The calibrated delay time Δt _D(n-1) , the point where the pulse train P2 begins to appear as the starting point of the output pulse waveform of the first branch is taken as Δt _D0 , Δt _D0 = 0, the window time of the nth branch W _{n-1 =} Δt _{Dn -Δt Dn-1} , the window times W ₁ , . The pulse time corresponding to the N branches, so that the pulse waveform data of the pulse train P2 is divided into corresponding N different gain waveforms, that is, the different gain waveforms of the output pulse of the waveform digitizing unit are obtained, and the digital acquisition of the large dynamic range transient pulse is realized. .

In this embodiment, the value of N is 3, and the point at which the pulse train begins to appear is taken as the starting point of the output pulse waveform of the first branch, the window time W1=Δt _D1 , and the window time W2 of the pulse waveform of the second branch =Δt _D2 -Δt _D1 .

The principle of the digital acquisition method of the large dynamic range transient pulse of the present invention is:

Different from the conventional data acquisition method, the digital acquisition system of the large dynamic range transient pulse established by the present invention first performs analog signal processing on the input signal (input transient pulse P1) before implementing waveform digitization, mainly including signal branching. , signal attenuation, signal delay, and signal recombination, so as to generate N pulse trains P2 separated in phase, and the gain of the split pulse can be adjusted according to the range coverage requirements. The resulting pulse train is then directly waveform digitized using an analog-to-digital converter ADC (high-speed analog-to-digital conversion chip). Therefore, the waveform digitizing instrument can perform N sampling on the transient pulse, and the N sampling process can be realized by using a single channel, so that the large dynamic range acquisition of the transient pulse can be realized.

The input signal of the large dynamic range transient pulse digital acquisition method of the present invention is a single transient pulse, and the obtained original waveform data is the pulse train waveform data including N transient pulses of different ranges. The vertical sensitivity A ₁ , ..., An , ..., _AN and the delay time Δt _D0 , ..., Δt _Dn , ..., Δt _DN of the _branch are saved to obtain multiple pulse waveforms, and the waveforms with different gains are extracted from the waveform data. waveform to achieve large dynamic range acquisition of transient pulses.

This method can directly use the existing high-speed acquisition system to directly build a new large dynamic range acquisition system, and only needs to introduce the analog signal processing unit described in step 1 in the front end.

Claims (8)

1. A digital acquisition method of a large dynamic range transient pulse is characterized by comprising the following steps:

step 1: establishing a digital acquisition system of the transient pulse with a large dynamic range; the digital acquisition system of the large dynamic range transient pulse comprises an analog signal processing unit and a waveform digitization unit; the analog signal processing unit is used for dividing the transient pulse into N paths of signals, respectively performing signal attenuation and signal delay on the N paths of signals, and compounding the N paths of signals after the signal delay to generate N pulse strings with separated phases; the waveform digitizing unit is used for converting the pulse string into waveform data; n is a positive integer greater than 1;

step 2: pre-calibrating the digital acquisition system of the large dynamic range transient pulse in the step 1 by using a standard signal;

and 3, step 3: collecting and extracting

Inputting the transient pulse P1 to be detected into a digital acquisition system of the large dynamic range transient pulse which is calibrated in advance, acquiring waveform data of the pulse train P2, acquiring and extracting different gain waveforms of the waveform data, and realizing digital acquisition of the large dynamic range transient pulse.

2. The digital acquisition method of the transient pulse with large dynamic range according to claim 1, wherein the analog signal processing unit in step 1 comprises N branches and one signal composite, wherein N is a positive integer;

each branch circuit comprises a signal branch circuit, a signal attenuation circuit and a signal delay circuit which are connected in sequence;

the input ends of the N signal shunts are connected with the transient pulse and used for dividing the transient pulse into N paths to be output;

the signal attenuation is used for carrying out gain adjustment on the output of the signal shunt circuit and outputting attenuation pulses;

the signal delay is used for adding signal delay time to the attenuation signal and outputting phase separation pulses so as to obtain N phase separation pulses corresponding to N shunts;

the signal composition is used for compositing the N phase separation pulses into a pulse train to be output; the output end of the signal composition is connected with the input end of the waveform digitizing unit.

3. The digital acquisition method of the transient pulse with large dynamic range according to claim 1, wherein the step 2 is specifically:

2.1 Demarcating vertical sensitivity of N shunts

2.1.1, producing an amplitude of V ₀ The standard square wave pulse signal of (4);

2.1.2, equally dividing the standard square wave pulse signal into two paths of output, wherein one path of output is connected to an external trigger channel TRIG of the waveform digitizing unit; the other path of output is connected to a signal channel CH of a digital acquisition system of the transient pulse with a large dynamic range to obtain pulse train waveform data corresponding to the N shunts;

2.1.3, carrying out analog-to-digital conversion on N pulse amplitudes in the pulse train waveform data obtained in the step 2.1.2 to obtain a quantized value CODE ₁ 、CODE ₂ 、…、CODE _N ；

2.1.4 according to the standard Square wave pulse Signal amplitude V ₀ With the quantified value CODE obtained in step 2.1.3 ₁ 、CODE ₂ 、…、CODE _N Calculating the vertical sensitivity A of the N branches ₁ 、…、A _N ；

2.2 Demarcating the delay times Δ t corresponding to the N branches _D0 、…、△t _D(N-1) 。

4. The digital acquisition method of the transient pulse with large dynamic range according to claim 3, wherein the step 3 is specifically:

3.1 Input the transient pulse P1 into a digital acquisition system of the transient pulse with a large dynamic range to obtain waveform data of the pulse train P2;

3.2 Vertical sensitivity A obtained with step 2.1.4) ₁ 、…、A _N Solving the amplitude value of the pulse train P2 waveform data; defining the position of a point on the waveform of the pulse train P2 as (x, y), wherein x represents the position sequence of the point in the waveform, y represents the actual quantization value corresponding to the point, and the amplitude value of the point is yA _X ；1≤x≤N；

Defining a pulse trainThe point where P2 begins to appear is taken as the starting point of the output pulse waveform of the 1 st branch, and the delay time Deltat calibrated in the step 2.2) is utilized _D0 、…、△t _D(N-1) And calculating the window time corresponding to each shunt circuit corresponding to the waveform data of the pulse train P2 so as to obtain N corresponding different gain waveforms and realize the digital acquisition of the transient pulse with a large dynamic range.

5. The digital acquisition method of the transient pulse with large dynamic range according to claim 3, wherein in step 2.1.4, the calculating the vertical sensitivities of the N branches specifically comprises:

setting the quantization bit number of the A/D conversion as M bits, the vertical sensitivity A of the nth branch circuit _n

Upper limit of range of nth shunt circuit B _n Comprises the following steps:

6. the digital acquisition method of the transient pulse with large dynamic range according to claim 3, wherein in step 2.1.2, the specific method for obtaining the pulse train waveform data corresponding to the N shunts is as follows:

by adjusting the amplitude V of a standard square-wave pulse signal ₀ And obtaining pulse train waveform data corresponding to the N branches.

7. The digital acquisition method of the transient pulse with large dynamic range according to claim 4, wherein the step 3.1) is specifically:

3.1.1, dividing the input transient pulse P1 into N paths of signals by utilizing signal branches;

3.1.2, respectively carrying out gain adjustment on the gains of the N paths of signals in the step 3.1.1 to obtain N paths of attenuation pulses;

3.1.3, adding signal delay time T to each path of attenuation signal in step 3.1.2 respectively _D1 …T _DN Obtaining N paths of phase separation pulses;

3.1.4, compounding the N paths of phase separation pulses in the step 3.1.3 to obtain a pulse train P2;

and 3.1.5, converting the pulse train P2 into waveform data by using a waveform digitizing unit.

8. The digital acquisition method of the transient pulse with large dynamic range according to any one of claims 1 to 7, characterized in that: the value of N is 3.

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