Digital acquisition method of large dynamic range transient pulse

Abstract

This invention relates to a high-speed signal acquisition method, specifically a digital acquisition method for large dynamic range transient pulses, solving the technical problem that existing technologies struggle to record transient pulses with large amplitude spans and significant range uncertainties. The digital acquisition method for large dynamic range transient pulses comprises the following steps: Step 1: Establishing a digital acquisition system for large dynamic range transient pulses; the digital acquisition system includes an analog signal processing unit and a waveform digitization unit; Step 2: Pre-calibrating the digital acquisition system for large dynamic range transient pulses using a standard signal; Step 3: Inputting a transient pulse P1 into the pre-calibrated digital acquisition system for large dynamic range transient pulses from Step 2, obtaining waveform data of the pulse train P2, and acquiring and extracting waveforms with different gains to achieve digital acquisition of large dynamic range transient pulses.

Description

Technical Field

[0001] This invention relates to a high-speed signal acquisition method, specifically to a digital acquisition method for transient pulses with a large dynamic range. Background Technology

[0002] Transient pulse signal measurement is in high demand in cutting-edge scientific research, such as high-energy physics, radiation detection, and detonation experiments. These physical experiments occur extremely briefly, and their physical detection signals are transient, typically appearing as single fast pulse signals on the nanosecond to microsecond scale. They also have large amplitude ranges and significant range uncertainties, with possible signal amplitudes ranging from a few millivolts to hundreds of volts. Furthermore, they are non-periodic and difficult to repeat in a single instance, posing considerable challenges to the accurate acquisition and recording of data by the backend acquisition and recording system.

[0003] Currently, the range coverage method is commonly used to acquire single transient pulses with large amplitude spans and significant range uncertainty. The principle is to first use a power divider to split the signal into multiple paths, and then acquire the signal using multiple oscilloscope or data acquisition instrument channels by overlapping the ranges. By setting different gains, these channels cover different ranges of the fast pulse signal. While this acquisition method can acquire fast pulse signals, it still faces challenges in handling inconsistencies caused by differences in synchronization triggering, biasing, conditioning circuits, and analog-to-digital converters between different channels. Summary of the Invention

[0004] The purpose of this invention is to address the technical problem that existing technologies struggle to record transient pulses with large amplitude spans and high range uncertainties, and to provide a digital acquisition method for transient pulses with a large dynamic range, which can achieve the acquisition of a large dynamic range of transient pulses.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] A digital acquisition method for transient pulses with a large dynamic range is characterized by the following steps:

[0007] Step 1: Establish a digital acquisition system for large dynamic range transient pulses; the digital acquisition system for large dynamic range transient pulses includes an analog signal processing unit and a waveform digitization unit; the analog signal processing unit is used to divide the transient pulse into N signals, and to attenuate and delay the N signals respectively, and then to combine the N delayed signals to generate N phase-separated pulse trains; the waveform digitization unit is used to convert the pulse trains into waveform data; N is a positive integer greater than 1;

[0008] Step 2: Pre-calibrate the digital acquisition system for the large dynamic range transient pulses from Step 1 using standard signals;

[0009] Step 3: Collection and Extraction

[0010] The transient pulse P1 to be measured is input into a pre-calibrated digital acquisition system for large dynamic range transient pulses to obtain waveform data of pulse train P2. Different gain waveforms of the waveform data are acquired and extracted to realize the digital acquisition of large dynamic range transient pulses.

[0011] Furthermore, the analog signal processing unit described in step 1 includes N branch paths and one signal composite, where N is a positive integer;

[0012] Each branch includes a signal branch, signal attenuation, and signal delay connected in sequence;

[0013] The input terminals of N signal branches are connected to the transient pulse, which is used to divide the transient pulse into N outputs;

[0014] Signal attenuation is used to adjust the gain of the output of the signal splitter and output an attenuation pulse;

[0015] Signal delay is used to add a signal delay time to the attenuated signal and output phase separation pulses, thereby obtaining N phase separation pulses corresponding to N branches;

[0016] Signal combining is used to combine N phase-separated pulses into a single pulse train output; the output of the signal combining unit is connected to the input of the waveform digitization unit.

[0017] Furthermore, step 2 specifically involves:

[0018] 2.1) Calibrate the vertical sensitivity of N branch paths.

[0019] 2.1.1 Generate a standard square wave pulse signal with an amplitude of V0;

[0020] 2.1.2. The standard square wave pulse signal is divided into two outputs. One output is connected to the external trigger channel TRIG of the waveform digitization unit; the other output is connected to the signal channel CH of the digital acquisition system for large dynamic range transient pulses, so as to obtain pulse train waveform data corresponding to N branches.

[0021] 2.1.3. Perform analog-to-digital conversion on the amplitudes of the N pulses in the pulse train waveform data obtained in step 2.1.2 to obtain quantization values ​​CODE1, CODE2, ..., CODE N ;

[0022] 2.1.4. Based on the amplitude V0 of the standard square wave pulse signal and the quantization values ​​CODE1, CODE2, ..., CODE obtained in step 2.1.3... N Calculate the vertical sensitivity A1, ..., A of the N branch paths. N ;

[0023] 2.2) Calibrate the delay time Δt corresponding to N branch paths D0 、…、△t D(N-1) .

[0024] Furthermore, step 3 specifically involves:

[0025] 3.1) The transient pulse P1 is input to a digital acquisition system for a large dynamic range transient pulse to obtain the waveform data of the pulse train P2;

[0026] 3.2) Using the vertical sensitivities A1, ..., A1 obtained in step 2.1.4 N Find the amplitude value of the pulse train P2 waveform data; define the position of a point on the pulse train P2 waveform as (x, y), where x represents the position order of the point in the waveform, and y represents the actual quantized value corresponding to the point. Then the amplitude value of that point is yA. X ; 1≤x≤N;

[0027] Define the point where pulse train P2 begins as the starting point of the output pulse waveform of the first branch, and use the delay time Δt calibrated in step 2.2). D0 、…、△t D(N-1) The window time corresponding to each branch of the waveform data of pulse train P2 is calculated to obtain N waveforms with different gains, thereby realizing the digital acquisition of transient pulses with a large dynamic range.

[0028] Further, in step 2.1.4, the calculation of the vertical sensitivity of the N branches specifically involves:

[0029] Let the quantization bit depth of the analog-to-digital converter be M bits, then the vertical sensitivity A of the nth branch is... n

[0030]

[0031] The upper limit of the range B of the nth branch is n for:

[0032]

[0033] Further, in step 2.1.2, the specific method for obtaining the pulse train waveform data corresponding to the N branches is as follows:

[0034] By adjusting the amplitude V0 of the standard square wave pulse signal, pulse train waveform data corresponding to N branches can be obtained.

[0035] Further, step 3.1) specifically refers to:

[0036] 3.1.1. The input transient pulse P1 is divided into N signals using signal splitting;

[0037] 3.1.2 Adjust the gain of each of the N signals in step 3.1.1 to obtain N attenuation pulses;

[0038] 3.1.3. Add a signal delay time T to each attenuated signal in step 3.1.2. D1 …T DN N phase separation pulses are obtained;

[0039] 3.1.4. Combine the N phase-separated pulses from step 3.1.3 to obtain a pulse train P2;

[0040] 3.1.5. Use the waveform digitization unit to convert the pulse train P2 into waveform data.

[0041] Furthermore, the value of N is 3.

[0042] Compared with the prior art, the beneficial effects of the technical solution of the present invention are:

[0043] 1. Before waveform digitization, this invention performs signal splitting, signal attenuation, and signal delay on transient pulses, and then performs signal recombination to generate a pulse train consisting of N phase-separated pulses. Then, the waveform digitization unit directly digitizes the formed pulse train, so that the waveform digitization instrument (analog-to-digital converter ADC) can sample the transient pulse N times. The N sampling process can be achieved using a single channel, thereby enabling the acquisition of a large dynamic range of transient pulses.

[0044] 2. This invention can sample transient pulses N times. The N sampling process can be achieved using a single channel. At the same time, the gain of the pulses in the N channels can be adjusted according to the range coverage requirements, thereby enabling the acquisition of a large dynamic range of transient pulses and meeting the recording requirements of transient pulses with large amplitude span and large range uncertainty.

[0045] 3. This invention utilizes a single analog-to-digital converter (ADC) in the waveform digitization unit to sample transient pulses multiple times, which can significantly reduce the size of the acquisition system.

[0046] 4. This invention can use the same analog-to-digital converter (ADC) in the waveform digitization unit to sample transient pulses multiple times and implement it using the same waveform digitization circuit (waveform digitization unit). It has the same RF drive, clock synchronization, bias adjustment, storage, triggering unit and other circuits, which can avoid the channel differences introduced by multi-channel parallel sampling. Attached Figure Description

[0047] Figure 1 This is a flowchart of the digital acquisition method for large dynamic range transient pulses according to the present invention.

[0048] Figure 2 This is a schematic diagram of a three-part circuit in an embodiment of the present invention.

[0049] Figure 3 This is a schematic diagram of the π-shaped resistor attenuation network in an embodiment of the present invention.

[0050] Figure 4 This is a schematic diagram of the integrated delay line device in an embodiment of the present invention.

[0051] Figure 5 This is a schematic diagram of the signal composition method based on adder in an embodiment of the present invention.

[0052] Figure 6 This is a block diagram of the waveform digitization unit in an embodiment of the present invention.

[0053] Figure 7 This is a schematic diagram of the transient pulse P1 in an embodiment of the present invention.

[0054] Figure 8 This is a schematic diagram of pulse train P2 in an embodiment of the present invention.

[0055] Figure 9 This is a waveform timing diagram in an embodiment of the present invention; where Trig: external trigger signal, P1: fast pulse to be tested, P2: pulse train, I1: first branch attenuation pulse (phase separation pulse), I2: second branch delay pulse, I3: third branch delay pulse, t w : The complete duration of a single pulse, Δt D1 The delay time of I2 compared to I1, Δt D2 : Delay time of I3 compared to I1, W1: First 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.

[0056] Figure 10 This is a schematic diagram of the pre-calibrated principle in an embodiment of the present invention. Detailed Implementation

[0057] This invention provides a digital acquisition method for transient pulses with a large dynamic range. The specific implementation method of this invention will be further described in detail below with reference to the accompanying drawings.

[0058] Step 1: Establish a digital acquisition system for large dynamic range transient pulses

[0059] like Figure 1 As shown, the digital acquisition system for large dynamic range transient pulses can be divided into two parts: an analog signal processing unit and a waveform digitization unit.

[0060] The main purpose of the analog signal processing unit is to generate pulse trains for the input signal and output a pulse train containing N transient pulses. Each pulse in the pulse train maintains the same waveform as the transient pulse, which is a multiple copy of the input pulse waveform. However, the amplitude of each pulse in the pulse train P2 is different and can be adjusted according to the detection range coverage requirements. In addition, the N transient pulses in the generated pulse train are separated in phase, where N is a positive integer greater than 1.

[0061] The waveform digitization unit inputs the output pulse train from the analog signal processing unit to the digital waveform acquisition instrument (analog-to-digital converter), mainly realizing waveform digitization functions such as analog signal conditioning, analog-to-digital conversion, synchronization timing, data storage, and data transmission; the waveform digitization unit is used to convert the pulse train into waveform data;

[0062] The analog signal processing unit Q1 mainly includes four processes: signal splitting, signal attenuation, signal delay, and signal recombination. The primary purpose of the analog signal processing unit is to generate N pulse trains P2, each with a different phase and amplitude, from the input signal (transient pulse P1). (See [link to relevant documentation]). Figure 8 .

[0063] 1.1) Signal splitting refers to dividing the input signal (transient pulse P1) into N output paths. Research shows this can be achieved using dedicated chips or discrete resistor networks. Discrete resistor networks can use equal or unequal division circuits. Dedicated chips, such as SSM's surface-mount power dividers including models PS1608G, PS2012G, and PS3216G, offer a maximum bandwidth of DC-20GHz and have advantages such as small size, low distortion, and low reflection.

[0064] In this embodiment, a three-part circuit based on a discrete resistor network is used, where N = 3, as follows: Figure 2 As shown; the three-way circuit consists of resistors R1, R2, R3, and R4, where R1 = R2 = R3 = R4 = 24.9Ω. The input and output impedances of the three-way circuit are both 50Ω. One end of resistor R1 serves as the input of the signal branch in step 1.1), connected to the input signal (transient pulse P1). The other end of resistor R1 is connected to one end of resistors R2, R3, and R4 respectively. The other ends of resistors R2, R3, and R4 serve as the branch outputs, which are the N-way outputs of the signal branch. The N-way outputs are connected to the attenuated N-way inputs (the input terminals of signal attenuation).

[0065] 1.2) Signal attenuation refers to the independent adjustment of the gain (amplitude) of the branched signal, which can be achieved by adding an attenuation circuit.

[0066] Corresponding to the N outputs of the signal branching in step 1.1), the signal attenuation includes a total of N attenuation circuits. Each attenuation circuit can be implemented using an integrated attenuator or a discrete resistor network. Integrated attenuators can be directly soldered onto the circuit board, offering advantages such as small size, high precision, and high reliability; discrete resistor networks offer flexible adjustment. In this embodiment, a discrete resistor network is preferred.

[0067] like Figure 3 As shown, this is a π-shaped attenuation network composed of discrete resistors, forming one attenuation circuit. From Figure 3 As can be seen, one end of resistors R5 and R6 is grounded, and the other ends of resistors R5 and R6 are respectively connected to both ends of resistor R7. The end of resistor R7 connected to R5 can be used as the signal input terminal VIN, and the end of resistor R7 connected to resistor R6 can be used as the signal output terminal Vout. Different attenuation factors can be determined by adjusting the resistance values ​​of resistors R5, R6, and R7. For example, when the attenuation value of the resistor network is 20dB, R4 = 24.7Ω, R5 = R6 = 61.1Ω. In this embodiment, resistors R5, R6, and R7 are preferably 0.1% high-precision thick-film high-frequency resistors. Other N-1 attenuation circuits are similar to... Figure 3 Similarly. Therefore, the signal attenuation consists of N attenuation circuits, with a total of N signal inputs and N signal outputs. The inputs of the N attenuation circuits are connected to the N outputs of the signal branch in step 1.1), and the outputs of the N attenuation circuits are connected to the N inputs of the signal delay.

[0068] 1.3) Signal delay refers to the signal delay time (t) added to each signal path. D1 To t DN Integrated surface-mount devices can be used to simulate delay lines.

[0069] The N inputs in step 1.3) correspond to the N outputs of signal attenuation in step 1.2. The signal delay includes a total of N delay circuits, and the signal delay time of each branch is t. Dn (n is the nth branch, N≥n≥1), the complete duration t of the input signal (transient pulse P1) is given. w Decision. w This is the starting point of the signal's appearance, the time from when it forms a pulse train to when it completely disappears into the substrate. To ensure that the pulses from each branch are separated in phase, t is required. Dn ≥(n-1)×t w , and t Dn -t D(n-1) ≥t w Delay circuits can be constructed using integrated surface-mount analog delay line devices; see appendix for details. Figure 4 This is a circuit for an analog delay line device (integrated delay line device). Figure 4Pin IN is the input terminal VIN of the analog delay line device, connected to Rin and an input resistor R, where R = 50Ω. Pins T1-T20 are the different output terminals of the analog delay line device, representing outputs with different delay times. The delay time gradually increases from T1 to T20, reaching the maximum delay time of the analog delay line device. To achieve signal matching, a resistor Rout is connected between the signal output terminal Vout of the analog delay line device and ground, where Rin = Rout = Z. line Z line To simulate the impedance of the delay line device. In this embodiment, Z is preferably... line =50Ω. The signal delay is composed of N delay circuits, which can be constructed using N analog delay line devices. It has N signal inputs and N signal outputs. The inputs of the N delay circuits are connected to the N outputs of signal attenuation in step 1.2), and the outputs of the N delay circuits are connected to the input of signal compositing.

[0070] 1.4) Signal combining refers to combining N phase-separated pulses into a single pulse train P2, the output of which is connected to the input of the waveform digitization unit. In this embodiment, signal combining is based on the principle of an additive circuit, combining multiple pulses into a single pulse train P2.

[0071] The signal compositing circuit is connected to the subsequent waveform digitization unit, such as... Figure 6 As shown, it includes RF drivers, analog-to-digital converters, processors, etc., such as Figure 5 As shown, the signal composite circuit can form an adder circuit with the differential amplifier at the input of the RF driver. The differential amplifier operates in DC-coupled, single-ended input mode. Vocm is the input common-mode voltage, R... g1 R g2 R is the gain resistor of the differential amplifier. f1 R f2 R is the feedback resistor of the differential amplifier. T1 R T2 RinL is the termination resistor for the differential amplifier, and RinL is the balancing resistor. To achieve optimal performance of the RF driver, input balance, transmission line termination matching, and feedback coefficient matching are required; therefore, RinL can be adjusted. g1 =R g2 R f1 =R f2 R T1 =R T2 RinL = 50Ω. Figure 5 In the middle, 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), R Cn R is the matching compensation resistor on the nth signal composite link. CnOne end is connected to the output of the nth branch of the signal delay, R C1 To R CN The other end is connected together as the output of the signal composite circuit, and is connected to the inverting input of the front-end RF driver in the waveform digitization unit. See Appendix. Figure 5 R can be determined in the following ways. Cn Resistance value: To ensure input balance, transmission line termination matching (signal resistance 50Ω matching), and reduce signal noise, the resistance value can be adjusted (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, when R linen Once the value is determined, R can be calculated. Cn The resistance value.

[0072] 1.5) Figure 1 The waveform digitization unit Q2 inputs the output pulse train P2 of the analog signal processing unit into the digital waveform acquisition instrument, mainly realizing waveform digitization functions such as analog signal conditioning, analog-to-digital conversion, synchronization timing, data storage, and data transmission; and directly digitizes the pulse train P2 formed in step 1.4).

[0073] like Figure 6 The diagram illustrates a waveform digitization instrument implemented using a conventional architecture, such as an ADC+FPGA waveform digitization architecture. This architecture primarily includes functional units such as an RF driver, an analog-to-digital converter (ADC), a control processor, clock synchronization, bias adjustment, storage, a trigger unit, and a host computer interface. This embodiment mainly targets transient pulse (P1) applications; therefore, an ADC with a speed of GSPS or higher is preferred. Furthermore, to meet the data processing requirements of the ADC output, a high-performance programmable logic device (FPGA) of 28nm or higher can be selected as the core processor to implement data processing and synchronization control functions. To reduce noise interference, a differential amplifier with a high common-mode rejection ratio (CMRR) is preferred as the RF driver. To extend the bandwidth to DC, DC coupling and single-ended input are preferred as the connection method between the input signal and the RF driver.

[0074] Step 2: Pre-calibrate the digital acquisition system for the large dynamic range transient pulses from Step 1 using standard signals.

[0075] Based on the large dynamic range transient pulse digital acquisition system 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 large dynamic range transient pulse digital acquisition system. This mainly involves pre-calibrating the vertical sensitivity and delay time of the pulse waveforms corresponding to the N branches of the analog signal processing unit.

[0076] like Figure 10 The diagram illustrates a pre-calibration connection method. Pre-calibration is performed using a standard square wave output from a signal source. First, an external signal source outputs a square wave pulse signal (standard signal) with an amplitude of V0. Then, a power divider is used to divide the square wave pulse signal into two equal outputs. One output of the power divider is connected to the external trigger channel TRIG of the waveform digitization unit, and the other is connected to the signal channel CH of the large dynamic range transient pulse digitization acquisition system. The large dynamic range transient pulse digitization acquisition system then acquires a set of pulse train waveform data corresponding to N outputs. Since the pulse attenuation of the N outputs is different, the amplitude of the pulse V0 output from the signal source can be adjusted so that all pulses in the pulse train are within the full-scale range of the analog-to-digital converter (ADC). The quantization values ​​CODE1, CODE2, ..., CODE corresponding to the amplitudes of the N pulses are then read. n ... CODE N (n is the nth branch, n≥1), assuming the quantization bits of the analog-to-digital converter (ADC) are M bits, then the vertical sensitivity A of the nth branch is... n for:

[0077]

[0078] The upper limit of the range B of the nth branch is n for:

[0079]

[0080] Then, select the same waveform feature point (e.g., the half-height value of a square wave) on the pulse train, and read the time of the same waveform feature point for each square wave on the pulse train. Let Δt be the time. D(n-1) The delay time of the nth branch compared to the 1st branch is equal to the time difference between the same waveform characteristic point of the nth square wave and the 1st square wave. See Appendix. Figure 9 .

[0081] Step 3: Acquire and extract the input transient pulses to achieve the acquisition of transient pulses with a large dynamic range.

[0082] For the large dynamic range transient pulse digital acquisition system established in step 1, a transient pulse P1 is input, and the pulse train P2 of transient pulse P1 is acquired. The waveform data of pulse train P2 is acquired and stored by the host computer. The acquisition software in the host computer extracts the sampling results of N transient pulses from the digital waveform data, and obtains 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. Specifically:

[0083] (1) Waveform acquisition

[0084] A transient pulse is input to the analog signal processing unit to obtain the transient pulse train; the waveform digitization unit performs analog-to-digital conversion on the pulse train to obtain a set of pulse train waveform data. In specific applications, the waveform recording time of the pulse train needs to be able to cover the entire pulse train.

[0085] (2) Waveform extraction

[0086] Waveform extraction mainly involves extracting the pulses from each branch of the pulse train waveform, and then determining the vertical sensitivity A of the N branches based on pre-calibrated values. N and delay time △t D(n-1) Multiple pulse waveforms are saved.

[0087] Vertical sensitivity A N Find the amplitude value of the pulse train P2 waveform data; let the position of a point on the pulse train P2 waveform be (x, y), where x represents the position of the point in the waveform, and y represents the quantized value of the analog-to-digital converter (ADC) at that point. Then the amplitude value of that point is yA. x ;N≥x≥1.

[0088] Calibrated delay time Δt D(n-1) The point where pulse train P2 begins to appear is taken as the starting point of the first branch output pulse waveform, and Δt is taken as the starting point. D0 , △t D0 =0, the window time W of the nth branch n-1 =△t Dn -△t Dn-1 The window times W1, ..., W2 corresponding to the first N-1 branch pulses are obtained. N-1 The pulse time corresponding to the Nth branch is after the (N-1)th branch window time, thus dividing the pulse waveform data of the pulse train P2 into N corresponding waveforms with different gains, that is, obtaining the different gain waveforms of the output pulse of the waveform digitization unit, realizing the digital acquisition of transient pulses with a large dynamic range.

[0089] In this embodiment, N is set to 3. The point where the pulse train begins is taken as the starting point of the output pulse waveform of the first branch, and its window time W1 = Δt. D1The window time W2 of the second branch pulse waveform is Δt. D2 -△t D1 .

[0090] The principle of the digital acquisition method for large dynamic range transient pulses in this invention is as follows:

[0091] Unlike conventional data acquisition methods, the large dynamic range transient pulse digital acquisition system established in this invention first performs analog signal processing on the input signal (input transient pulse P1) before waveform digitization. This mainly includes four processes: signal splitting, signal attenuation, signal delay, and signal recombination, thereby generating N phase-separated pulse trains P2. The gain of the split pulses can be adjusted according to the range coverage requirements. Then, an analog-to-digital converter (ADC) is used to directly digitize the formed pulse trains. This allows the waveform digitizing instrument to sample the transient pulse N times, and the N sampling process can be achieved using a single channel, thus enabling the acquisition of a large dynamic range transient pulse.

[0092] The digital acquisition method for large dynamic range transient pulses in this invention targets a single transient pulse as the input signal. The obtained raw waveform data is a pulse train waveform data including N transient pulses with different ranges. It is necessary to determine the vertical sensitivity A1, ..., A of the N pre-calibrated branches. n A N and delay time △t D0 、…、△t Dn 、…、△t DN Multiple pulse waveforms are saved, and waveforms with different gains are extracted from the waveform data to achieve a large dynamic range acquisition of transient pulses.

[0093] This method can directly utilize existing high-speed acquisition systems to build new large dynamic range acquisition systems, simply by introducing the analog signal processing unit described in step 1 at the front end.

Claims

1. A digital acquisition method for transient pulses with a large dynamic range, characterized in that, Includes the following steps: Step 1: Establish a digital acquisition system for large dynamic range transient pulses; the digital acquisition system for large dynamic range transient pulses includes an analog signal processing unit and a waveform digitization unit; the analog signal processing unit is used to divide the transient pulse into N signals, and to perform signal attenuation and signal delay on the N signals respectively, and then to combine the N delayed signals to generate N phase-separated pulse trains. The waveform digitization unit is used to convert the pulse train into waveform data; N is a positive integer greater than 1; Step 2: Pre-calibrate the digital acquisition system for the large dynamic range transient pulses from Step 1 using standard signals, specifically: 2.1) Calibrate the vertical sensitivity of the N branch paths; 2.1.1 Generate a standard square wave pulse signal with an amplitude of V0; 2.1.

2. The standard square wave pulse signal is divided into two outputs. One output is connected to the external trigger channel TRIG of the waveform digitization unit; the other output is connected to the signal channel CH of the digital acquisition system for large dynamic range transient pulses, so as to obtain pulse train waveform data corresponding to N branches. 2.1.

3. Perform analog-to-digital conversion on the amplitudes of the N pulses in the pulse train waveform data obtained in step 2.1.2 to obtain quantization values ​​CODE1, CODE2, ..., CODE N ; 2.1.

4. Based on the amplitude V0 of the standard square wave pulse signal and the quantization values ​​CODE1, CODE2, ..., CODE obtained in step 2.1.3... N Calculate the vertical sensitivity A1, ..., A of the N branch paths. N ; 2.2) Calibrate the delay time Δt corresponding to N branch paths. D0 、…、△t D（N-1） ; Step 3: Collection and Extraction; The transient pulse P1 to be measured is input into a pre-calibrated digital acquisition system for large dynamic range transient pulses to obtain waveform data of pulse train P2. Different gain waveforms are acquired and extracted to achieve digital acquisition of large dynamic range transient pulses. Specifically: 3.1) The transient pulse P1 is input to a digital acquisition system for a large dynamic range transient pulse to obtain the waveform data of the pulse train P2; 3.2) Using the vertical sensitivities A1, ..., A1 obtained in step 2.1.4 N Find the amplitude value of the pulse train P2 waveform data; define the position of a point on the pulse train P2 waveform as (x, y), where x represents the position order of the point in the waveform, and y represents the actual quantized value corresponding to the point. Then the amplitude value of that point is yA. X ; 1≤x≤N; Define the point where pulse train P2 begins as the starting point of the output pulse waveform of the first branch, and use the delay time Δt calibrated in step 2.2). D0 、…、△t D（N-1） The window time corresponding to each branch of the waveform data of pulse train P2 is calculated to obtain N waveforms with different gains, thereby realizing the digital acquisition of transient pulses with a large dynamic range.

2. The digital acquisition method for large dynamic range transient pulses according to claim 1, characterized in that, The analog signal processing unit described in step 1 includes N branch paths and one signal composite, where N is a positive integer; Each branch includes a signal branch, signal attenuation, and signal delay connected in sequence; The input terminals of the N signal branches are connected to the transient pulse, which is used to divide the transient pulse into N outputs; The signal attenuation is used to adjust the gain of the output of the signal splitter and output an attenuation pulse; The signal delay is used to add a signal delay time to the attenuated signal and output a phase separation pulse, thereby obtaining N phase separation pulses corresponding to N branches; The signal combining is used to combine N phase-separated pulses into a pulse train for output; the output terminal of the signal combining is connected to the input terminal of the waveform digitization unit.

3. The digital acquisition method for large dynamic range transient pulses according to claim 2, characterized in that, In step 2.1.4, the calculation of the vertical sensitivity of the N branches specifically involves: Let the quantization bit depth of the analog-to-digital converter be M bits, then the vertical sensitivity A of the Nth branch is... N for: ； The upper limit of the range B of the Nth branch is... N for: 。 4. The digital acquisition method for large dynamic range transient pulses according to claim 3, characterized in that, In step 2.1.2, the specific method for obtaining the pulse train waveform data corresponding to the N branches is as follows: By adjusting the amplitude V0 of the standard square wave pulse signal, pulse train waveform data corresponding to N branches can be obtained.

5. The digital acquisition method for large dynamic range transient pulses according to claim 4, characterized in that, Step 3.1) specifically involves: 3.1.

1. The input transient pulse P1 is divided into N signals using signal splitting; 3.1.2 Adjust the gain of each of the N signals in step 3.1.1 to obtain N attenuation pulses; 3.1.

3. Add a signal delay time T to each attenuated signal in step 3.1.

2. D1 …T DN N phase separation pulses are obtained; 3.1.

4. Combine the N phase-separated pulses from step 3.1.3 to obtain a pulse train P2; 3.1.

5. Use the waveform digitization unit to convert the pulse train P2 into waveform data.

6. The digital acquisition method for large dynamic range transient pulses according to any one of claims 1-5, characterized in that: The value of N is 3.

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