High-precision timing system and method based on dual-channel time measurement

Abstract

This application relates to a high-precision timing system and method based on dual-channel time measurement. The system includes: a filtering module for receiving analog signals output from a particle detector, filtering and denoising the analog signals, and converting the processed signals into two co-source valid signals for output; a time measurement module for receiving the two co-source valid signals, and by configuring a first discrimination threshold and a second discrimination threshold, performing discrimination processing on the two co-source valid signals respectively, capturing the characteristic time when each signal reaches the corresponding discrimination threshold, and outputting the first characteristic time and the second characteristic time; and a data processing module for calculating and storing the high-precision arrival time based on the approximately linear characteristics of the rising edge of the signal pulse, according to the first discrimination threshold, the second discrimination threshold, the first characteristic time, and the second characteristic time. Using this system, particle arrival time measurement can be achieved with both stability and high precision, meeting the application requirements of high-precision timing scenarios.

Description

Technical Field

[0001] This application relates to the field of signal processing technology, and in particular to a high-precision timing system and method based on dual-channel time measurement. Background Technology

[0002] With the continuous development of technologies in various fields such as basic scientific research, key engineering applications, and daily life, high-precision time measurement technology has become the core "time standard" supporting progress in various fields. Every order of magnitude improvement in its accuracy can drive a number of technological breakthroughs, especially in fields such as basic physics, astronomy, and quantum mechanics, where it is a key tool for verifying theories and discovering new phenomena. High-precision timing, as the core foundation of high-precision time measurement, is currently mainly achieved through discrimination circuits, specifically including three mainstream methods: leading-edge timing, zero-crossing timing, and constant-ratio timing. Various detectors, as the core interface for studying particle characteristics, have their output signals widely used for measuring particle arrival times.

[0003] However, traditional timing methods of discrimination circuits are significantly affected by noise from detectors and electronic circuits. Among them, the jitter of the detector output signal (mainly manifested as changes in signal amplitude and rise time) plays a decisive role in timing accuracy. Leading-edge timing cannot eliminate the dual timing errors caused by changes in signal amplitude and rise time. Zero-crossing timing and constant-ratio timing can only eliminate the errors caused by amplitude changes, but cannot solve the timing errors caused by rise time changes. This makes it impossible for existing timing discrimination circuits to completely eliminate timing errors caused by signal jitter, and thus cannot meet the urgent needs of various fields for ultra-high precision timing. Summary of the Invention

[0004] Therefore, it is necessary to provide a high-precision timing system and method based on dual-channel time measurement to address the aforementioned technical problems.

[0005] A high-precision timing system based on dual-channel time measurement, the system comprising:

[0006] The system includes a filtering module, a time measurement module, and a data processing module, wherein the time measurement module is connected to both the filtering module and the data processing module.

[0007] The filtering module is used to receive the analog signal output by the particle detector, perform filtering and noise reduction processing on the analog signal, and convert the processed signal into two valid signals from the same source for output.

[0008] The time measurement module is used to receive the two valid signals from the same source, and to perform discrimination processing on the two valid signals from the same source by configuring a first discrimination threshold and a second discrimination threshold, respectively, capturing the characteristic time when each signal reaches the corresponding discrimination threshold, and outputting the first characteristic time and the second characteristic time.

[0009] The data processing module is used to calculate and store the high-precision arrival time based on the approximate linear characteristics of the rising edge of the signal pulse, according to the first discrimination threshold, the second discrimination threshold, the first characteristic time, and the second characteristic time.

[0010] A high-precision timing method based on dual-channel time measurement, the method comprising:

[0011] The system receives the analog signal output from the particle detector, performs filtering and noise reduction processing on the analog signal, and converts the processed signal into two valid signals from the same source for output.

[0012] By configuring a first discrimination threshold and a second discrimination threshold, two valid signals from the same source are processed for discrimination, the characteristic moment when each signal reaches the corresponding discrimination threshold is captured, and the first characteristic moment and the second characteristic moment are output.

[0013] Based on the approximately linear characteristics of the rising edge of the signal pulse, the high-precision arrival time is calculated and stored according to the first discrimination threshold, the second discrimination threshold, the first characteristic time and the second characteristic time.

[0014] The aforementioned high-precision timing system and method based on dual-channel time measurement effectively reduces noise interference on subsequent time measurements by filtering and denoising the analog signal output by the particle detector through a filtering module. Simultaneously, it converts the processed signal into two co-source valid signals, laying a stable signal foundation for accurate dual-channel measurement. The time measurement module configures dual discrimination thresholds and separately discriminates the two co-source signals, capturing corresponding characteristic moments. This utilizes dual reference points to improve the stability and reliability of time capture, avoiding the limitations of single-threshold measurement. The data processing module, based on the approximately linear characteristics of the signal pulse rising edge, combines the dual thresholds and corresponding characteristic moments to accurately deduce the high-precision arrival time, significantly reducing timing deviations caused by signal amplitude variations and rise time differences, thus significantly improving the accuracy of particle arrival time measurement. Furthermore, storing the high-precision arrival time provides a reliable basis for subsequent data traceability and analysis. This invention can achieve high-precision timing and time measurement by combining detectors with known or unknown response characteristics, meeting the urgent need for high-precision timing in various fields. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a high-precision timing system based on dual-channel time measurement in one embodiment.

[0016] Figure 2 This is a schematic diagram of the structure of the filtering module in one embodiment;

[0017] Figure 3This is a schematic diagram of the time measurement module in one embodiment;

[0018] Figure 4 This is a schematic diagram of the data processing module in one embodiment;

[0019] Figure 5 This is a schematic diagram of the structure of a multi-threshold comparison and discrimination circuit in one embodiment. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0021] In one embodiment, such as Figure 1 As shown, a high-precision timing system based on dual-channel time measurement is provided, including:

[0022] The system includes a filtering module, a time measurement module, and a data processing module. The time measurement module is connected to both the filtering module and the data processing module.

[0023] The filtering module is used to receive the analog signal output by the particle detector, perform filtering and noise reduction processing on the analog signal, and convert the processed signal into two valid signals from the same source for output.

[0024] The time measurement module is used to receive two valid signals from the same source. By configuring a first discrimination threshold and a second discrimination threshold, it performs discrimination processing on the two valid signals from the same source respectively, captures the characteristic time when each signal reaches the corresponding discrimination threshold, and outputs the first characteristic time and the second characteristic time.

[0025] The data processing module is used to calculate and store the high-precision arrival time based on the approximate linear characteristics of the rising edge of the signal pulse, according to the first discrimination threshold, the second discrimination threshold, the first characteristic time, and the second characteristic time.

[0026] In the aforementioned high-precision timing system based on dual-channel time measurement, the filtering module performs noise reduction processing on the analog signal output by the particle detector, effectively weakening the impact of noise interference on subsequent time measurements. Simultaneously, the processed signal is converted into two valid signals from the same source, laying a stable signal foundation for accurate dual-channel measurement. The time measurement module configures dual discrimination thresholds and separately discriminates the two signals from the same source, capturing corresponding characteristic moments. Utilizing dual reference points improves the stability and reliability of moment capture, avoiding the limitations of single-threshold measurement. The data processing module, based on the approximately linear characteristics of the signal pulse rising edge, combines the dual thresholds and corresponding characteristic moments to accurately deduce the high-precision arrival time, significantly reducing timing deviations caused by factors such as signal amplitude variations and rise time differences, thus significantly improving the accuracy of particle arrival time measurement. Furthermore, storing the high-precision arrival time provides a reliable basis for subsequent data traceability and analysis. This embodiment of the invention can achieve particle arrival time measurement with both stability and high precision, meeting the application requirements of high-precision timing scenarios.

[0027] like Figure 1 As shown, the analog signal output by the detector is input into this system. The filtering module first filters the noise signal and converts the amplified valid input signal into two inputs to the time measurement module. Considering the different output characteristics of different particle detectors, the filtering module has an adjustable amplification factor to adapt to different types of particle detection. Then, the time measurement module measures the arrival times of the two signals by setting different discrimination thresholds to obtain T1 and T2, which are then input to the data processing module. Finally, the data processing module processes the data using a timing algorithm to obtain a high-precision arrival time T and stores it in the system. Considering the trace delay of the electronic circuit, the delay time needs to be calibrated after the system is built and written into the timing algorithm. The method of this invention solves the problem of high-precision timing and also takes into account the timing measurement of multiple types of particle detection.

[0028] In one embodiment, the filtering module includes a filter circuit with adjustable passband and an amplifier circuit with adjustable amplification factor; the passband of the filter circuit covers the frequency range of the input analog signal; the amplification factor of the amplifier circuit can be independently adjusted to adapt to the output signal of the particle detector with different response characteristics.

[0029] In this embodiment, considering the differences in response characteristics between different types of particle detectors, the varying response characteristics of the same particle detector to different numbers of particles, and the impact of environmental noise on timing, the filtering module needs to process the analog signal output by the detector, such as... Figure 2 The diagram shows the structure of the filtering module. Both the input and output of the module are analog signals.

[0030] In one embodiment, the amplification factor of the amplifier circuit is adjusted through two-stage amplification logic, wherein the first-stage amplification logic is integrated by a filter circuit, and the second-stage amplification logic is implemented by an independent amplifier circuit; the amplitudes of the two valid signals from the same source are adjusted in coordination by the two-stage amplification logic to adapt to the range requirements of the first and second discrimination thresholds.

[0031] In this embodiment, for different types of particle detector output signals, the actual signal frequency ( f Smin ~ f Smax The bandwidth is not fixed, therefore a filter circuit with adjustable bandwidth needs to be designed, and its bandwidth range ( f L ~ f H It should satisfy:

[0032] (1)

[0033] (2)

[0034] After amplification by the amplifier circuit, the signals are input to the time measurement module in two separate paths, with the two output signals S1 and S2 being identical. To ensure timing accuracy, the amplitudes of S1 and S2 must meet certain conditions, and since the input signal amplitudes of different detectors may vary significantly, the amplitudes of S1 and S2 must be adjustable to suit different application scenarios. However, the amplification factor of the filter circuit... A 1. Due to its bandwidth limitations, it cannot be adjusted independently; therefore, an amplification factor is added to the filtering module. A 2. Adjustable amplifier circuit. For front-end detectors in fixed applications, the filter circuit amplification factor... A 1 and amplifier circuit amplification factor A 2. If the amplitude of the input signal S varies within the range of 2, then... V Smin ~ V Smax Then the amplitudes of S1 and S2 V The range is:

[0035] (3)

[0036] In one embodiment, the time measurement module includes a discrimination circuit and a time measurement circuit; the discrimination circuit includes two comparators with unequal thresholds, corresponding to a first discrimination threshold and a second discrimination threshold, respectively, for threshold comparison of two valid signals from the same source, and outputting two digital square wave signals; the time measurement circuit is used to capture the trigger time of the two digital square wave signals to obtain a first characteristic time and a second characteristic time.

[0037] In this embodiment, as Figure 3 The diagram shown illustrates the structure of the time measurement module, which includes a discrimination circuit and a time measurement circuit. The discrimination circuit consists of two different thresholds. V th1 and V th2 The comparator implementation ultimately inputs two square wave signals to the time measurement circuit to obtain two time points. T 1 and T 2.

[0038] In one embodiment, the two digital square wave signals output by the discrimination circuit are CMOS signals, and the time measurement circuit receives the two CMOS signals through two independent channels to synchronously capture the corresponding trigger times.

[0039] In one embodiment, when configuring a first discrimination threshold and a second discrimination threshold, the first discrimination threshold is less than the second discrimination threshold, and both fall within a preset amplitude range of the rising edge of the signal pulse; the preset amplitude range is the range in which the signal amplitude rises from 10% to 90% of the maximum amplitude.

[0040] In this embodiment, because the timing accuracy of a single-threshold-based discrimination circuit is affected by changes in amplitude and rise time, a dual-channel, dual-threshold discrimination circuit is used in this invention. The rise time of a signal pulse is generally defined as the time it takes for the signal amplitude to rise from 10% to 90% of its maximum value; at this point, the curve approximates a straight line. Therefore, to further improve timing accuracy, if... V th1 < V th2 The threshold of the dual channels V th1 and V th2 It can be configured as follows:

[0041] (4)

[0042] (5)

[0043] In one embodiment, the adjustable range of the first discrimination threshold and the second discrimination threshold is 0~3.3V.

[0044] In one embodiment, the high-precision arrival time is calculated based on the approximate linearity of the rising edge of the signal pulse, according to the first discrimination threshold, the second discrimination threshold, the first characteristic time, and the second characteristic time. This includes: based on the approximate linearity of the rising edge of the signal pulse, using the correlation between the first discrimination threshold, the second discrimination threshold, and the corresponding characteristic time, the time corresponding to the signal amplitude being 0 is deduced, thus obtaining the high-precision arrival time.

[0045] In this embodiment, as Figure 4 The diagram shows the structure of the data processing module, which includes an algorithm processing unit and a storage unit. The measured time... T 1 and T 2. Data is transmitted to the algorithm processing unit for processing, and then stored in the storage unit for subsequent use by later modules. Since the rising edge of the pulse signal obtained from the test is generally quite steep and can be approximated as a straight line, the algorithm processing unit calculates the arrival time according to the following formula. T :

[0046] (6)

[0047] In one embodiment, during the operation of the data processing module, pre-calibrated electronic circuit trace delay compensation parameters are incorporated after the system is built to offset the fixed delay error generated during signal transmission between modules.

[0048] In one specific embodiment, the effectiveness of the system of the present invention was verified through experiments:

[0049] When the measurement time or time difference is known, the timing accuracy is calculated from the root mean square error (RMS). n The calculation formula is as follows:

[0050] (7)

[0051] in X obs,i and X model,i No. i The test value and the actual value.

[0052] For the same device, the timing effects of rise time variation and amplitude variation are similar. To measure the impact of actual amplitude and rise time variation on timing accuracy, the deviation of the input signal from the normal value is considered as a standard normal distribution, and the standard deviation of the variation is assumed to be 5% of the standard value. That is, the probability density function of the variation value satisfies the following formula:

[0053] (8)

[0054] The effects of amplitude variation and rise time variation on RMS accuracy were calculated. The single threshold was set to 1 / 10, 1 / 5 and 1 / 2 of the standard normalized amplitude, respectively, and the double threshold was set to 1 / 5 and 1 / 2 of the amplitude, respectively. The leading edge timing calculation and analysis were performed on square wave, positive line wave and triangular wave with a standard rise time of 1ns. The RMS accuracy statistics of the timing are shown in Table 1 and Table 2.

[0055] Table 1. RMS accuracy statistics when amplitude varies with a fixed rise time of 1 ns (unit: ps)

[0056]

[0057] Table 2. RMS accuracy statistics for rise time variations when the standard rise time is 1 ns (unit: ps)

[0058]

[0059] It can be observed that, regardless of whether the input is a square wave, triangle wave, or sine wave, the RMS accuracy using dual-threshold comparison timing is significantly improved compared to single-threshold timing, and the impact of amplitude and rise time variations on RMS accuracy can be effectively suppressed. However, in reality, the rising edges of square and triangle waves are not perfectly straight lines, so the improvement in accuracy still depends on actual measurement results.

[0060] This invention constructs a practical dual-threshold comparison and discrimination circuit, and the circuit design diagram is shown below. Figure 5 As shown, it is implemented using two single-threshold comparator circuits. The threshold voltages of the two comparators are set differently, with an adjustable range of 0~3.3V. After comparison by the two circuits, a CMOS signal is output, which is then connected to the two input channels of the time measurement device.

[0061] This invention utilizes a signal generator to produce square waves (rise time 10 ns), sine waves (rise time 5 μs), and square waves (rise time 5 μs) to test the RMS accuracy of the time difference between two signals with different amplitudes. If the measurement time or time difference is unknown, the timing RMS accuracy is calculated from the standard deviation. n The calculation formula is as follows:

[0062] (9)

[0063] in X i It is the first i The second test value, The average value is the sum of all measured values. For the dual threshold voltage test, 0.5V and 1V were selected. For comparison, the single threshold voltage test was conducted at 0.5V and 1V respectively. The final test results are shown in Table 3. It can be observed that using the multi-threshold discrimination circuit improves the RMS accuracy of time measurement by 18% to 65% compared to the single-threshold discrimination circuit. Therefore, the multi-threshold discrimination circuit exhibits good timing accuracy regardless of the waveform input.

[0064] Table 3. RMS accuracy test statistics for dual-threshold and single-threshold discrimination circuits (unit: ps)

[0065]

[0066] This invention builds a high-precision timing system based on a filtering module, a time measurement module, and a data processing module. It can combine detectors with known or unknown response characteristics to achieve high-precision timing and time measurement, meeting the urgent needs of various fields for high-precision timing.

[0067] In one embodiment, a high-precision timing method based on dual-channel time measurement is provided, including:

[0068] It receives the analog signal output from the particle detector, performs filtering and noise reduction on the analog signal, and converts the processed signal into two valid signals from the same source for output.

[0069] By configuring a first discrimination threshold and a second discrimination threshold, two valid signals from the same source are processed for discrimination, the characteristic moment when each signal reaches the corresponding discrimination threshold is captured, and the first characteristic moment and the second characteristic moment are output.

[0070] Based on the approximately linear characteristics of the rising edge of the signal pulse, the high-precision arrival time is calculated and stored according to the first discrimination threshold, the second discrimination threshold, the first characteristic time and the second characteristic time.

[0071] Specific limitations regarding the high-precision timing method based on dual-channel time measurement can be found in the limitations of the high-precision timing system based on dual-channel time measurement described above, and will not be repeated here. Each module in the aforementioned high-precision timing system based on dual-channel time measurement can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independently of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the corresponding operations of each module.

[0072] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0073] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A high-precision timing system based on dual-channel time measurement, characterized in that, The system includes a filtering module, a time measurement module, and a data processing module, wherein the time measurement module is connected to the filtering module and the data processing module respectively. The filtering module is used to receive the analog signal output by the particle detector, perform filtering and noise reduction processing on the analog signal, and convert the processed signal into two valid signals from the same source for output. The time measurement module is used to receive the two valid signals from the same source, and to perform discrimination processing on the two valid signals from the same source by configuring a first discrimination threshold and a second discrimination threshold, respectively, capturing the characteristic time when each signal reaches the corresponding discrimination threshold, and outputting the first characteristic time and the second characteristic time. The data processing module is used to calculate and store the high-precision arrival time based on the approximate linear characteristics of the rising edge of the signal pulse, according to the first discrimination threshold, the second discrimination threshold, the first characteristic time, and the second characteristic time. The time measurement module includes a discrimination circuit and a time measurement circuit; The discrimination circuit includes two comparators with different thresholds, corresponding to the first discrimination threshold and the second discrimination threshold respectively, for comparing the thresholds of two valid signals from the same source and outputting two digital square wave signals. The time measurement circuit is used to capture the trigger time of two digital square wave signals to obtain the first characteristic time and the second characteristic time. The two digital square wave signals output by the discrimination circuit are CMOS signals. The time measurement circuit receives the two CMOS signals through two independent channels and synchronously captures the corresponding trigger time. When configuring the first discrimination threshold and the second discrimination threshold, the first discrimination threshold is less than the second discrimination threshold, and both fall within the preset amplitude range of the rising edge of the signal pulse; the preset amplitude range is the range in which the signal amplitude rises from 10% to 90% of the maximum amplitude. Based on the approximately linear characteristics of the rising edge of the signal pulse, and using the first discrimination threshold, the second discrimination threshold, the first characteristic time, and the second characteristic time as parameters, a high-precision arrival time is calculated, including: Based on the approximately linear characteristics of the rising edge of the signal pulse, the time corresponding to the signal amplitude of 0 is deduced by using the correlation between the first and second discrimination thresholds and the corresponding characteristic time, thus obtaining the high-precision arrival time.

2. The system according to claim 1, characterized in that, The filtering module includes a filter circuit with adjustable passband and an amplifier circuit with adjustable amplification factor. The passband of the filter circuit covers the frequency range of the input analog signal; The amplification factor of the amplifier circuit can be adjusted independently to adapt to the output signals of particle detectors with different response characteristics.

3. The system according to claim 2, characterized in that, The amplification factor of the amplifier circuit is adjusted through two stages of amplification logic, wherein the first stage of amplification logic is integrated by a filter circuit, and the second stage of amplification logic is implemented by an independent amplifier circuit. The amplitudes of the two valid signals from the same source are adjusted in coordination by the two-stage amplification logic to match the range requirements of the first and second discrimination thresholds.

4. The system according to claim 1, characterized in that, The adjustable range of the first and second discrimination thresholds is 0~3.3V.

5. The system according to claim 1, characterized in that, During the operation of the data processing module, the electronic circuit trace delay compensation parameters that were pre-calibrated after the system was built are incorporated to offset the fixed delay error generated during signal transmission between modules.

6. A high-precision timing method based on dual-channel time measurement implemented in the system described in any one of claims 1-5, characterized in that, The method includes: The system receives the analog signal output from the particle detector, performs filtering and noise reduction processing on the analog signal, and converts the processed signal into two valid signals from the same source for output. By configuring a first discrimination threshold and a second discrimination threshold, two valid signals from the same source are processed for discrimination, the characteristic moment when each signal reaches the corresponding discrimination threshold is captured, and the first characteristic moment and the second characteristic moment are output. Based on the approximately linear characteristics of the rising edge of the signal pulse, the high-precision arrival time is calculated and stored according to the first discrimination threshold, the second discrimination threshold, the first characteristic time and the second characteristic time.

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