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

Abstract

The invention relates to a high-precision timing system and method based on dual-channel time measurement. The system comprises a filtering module which is used for receiving an analog signal output by a particle detector, carrying out filtering and noise reduction processing on the analog signal, and converting the processed signal into two paths of homologous effective signals for output; the time measurement module is used for receiving two paths of homologous effective signals, performing discrimination processing on the two paths of homologous effective signals by configuring a first discrimination threshold value and a second discrimination threshold value, capturing a characteristic moment when each path of signal reaches the corresponding discrimination threshold value, and outputting a first characteristic moment and a second characteristic moment; and the data processing module is used for carrying out operation according to the first discrimination threshold, the second discrimination threshold, the first characteristic moment and the second characteristic moment based on the approximate linear characteristic of the rising edge of the signal pulse, calculating a high-precision arrival moment and storing the high-precision arrival moment. By adopting the system, stable and high-precision particle arrival time measurement can be realized, and the application requirement of a high-precision timing scene is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of signal processing, in particular to a high-precision timing system and method based on double-channel time measurement. BACKGROUND

[0002] With the continuous development of basic scientific research, key engineering applications and daily life in many fields, high-precision time measurement technology has become the core "time reference" supporting the progress of various fields. Each time the precision is improved by one order of magnitude, it can promote a batch of technological breakthroughs, especially in the fields of fundamental physics, astronomy, quantum, etc., which are the key tools for verifying theories and discovering new phenomena. As the core basis of high-precision time measurement, high-precision timing is currently mainly realized through discrimination circuits, including three mainstream ways of front edge timing, zero crossing timing and constant ratio timing. Various detectors are the core interface for studying particle characteristics, and their output signals are widely used for measuring the time of particle arrival.

[0003] However, the traditional discrimination circuit timing method is significantly affected by the noise brought by the detector and electronic circuit. The jitter of the detector output signal (mainly reflected in the change of signal amplitude and rise time) plays a decisive role in timing accuracy. The front edge timing cannot eliminate the double timing error caused by the change of signal amplitude and rise time, and the zero crossing timing and constant ratio timing can only eliminate the error caused by the change of amplitude, but it is difficult to solve the timing error caused by the change of rise time. This makes the existing timing discrimination circuit always unable to completely eliminate the timing error caused by signal jitter, and thus cannot meet the urgent needs of various fields for ultra-high precision timing. SUMMARY

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

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

[0006] a filtering module, a time measurement module and a data processing module, the time measurement module being connected to the filtering module and the data processing module respectively; The filtering module is used for receiving an analog signal output by a particle detector, filtering and denoising the analog signal, and converting the processed signal into two-way homologous effective signal output; The time measurement module is used for receiving the two-way homologous effective signal, configuring a first discrimination threshold and a second discrimination threshold, discriminating the two-way homologous effective signal 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.

[0007] A high-precision timing method based on dual-channel time measurement, the method comprising: 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, and 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.

[0008] 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

[0009] Figure 1 This is a schematic diagram of a high-precision timing system based on dual-channel time measurement in one embodiment. Figure 2 This is a schematic diagram of the structure of the filtering module in one embodiment; Figure 3 This is a schematic diagram of the time measurement module in one embodiment; Figure 4 This is a schematic diagram of the data processing module in one embodiment; Figure 5 This is a schematic diagram of the structure of a multi-threshold comparison and discrimination circuit in one embodiment. Detailed Implementation

[0010] 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.

[0011] In one embodiment, such as Figure 1 As shown, a high-precision timing system based on dual-channel time measurement is provided, including: 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. 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 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. 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.

[0012] 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 enables particle arrival time measurement with both stability and high precision, meeting the application requirements of high-precision timing scenarios.

[0013] like Figure 1As 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.

[0014] 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.

[0015] 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.

[0016] 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.

[0017] 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: (1) (2) 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: (3) 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] 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: (4) (5) In one embodiment, the adjustable range of the first discrimination threshold and the second discrimination threshold is 0~3.3V.

[0022] 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.

[0023] 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 : (6) 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.

[0024] In one specific embodiment, the effectiveness of the system of the present invention was verified through experiments: 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: (7) in X obs,i and X model,i No. i The test value and the actual value.

[0025] 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: (8) 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.

[0026] Table 1. RMS accuracy statistics when amplitude varies with a fixed rise time of 1 ns (unit: ps)

[0027] Table 2. RMS accuracy statistics for rise time variations when the standard rise time is 1 ns (unit: ps)

[0028] 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 is 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.

[0029] 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.

[0030] 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: (9) 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.

[0031] Table 3. RMS accuracy test statistics for dual-threshold and single-threshold discrimination circuits (unit: ps)

[0032] 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.

[0033] In one embodiment, a high-precision timing method based on dual-channel time measurement is provided, including: 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. By configuring a first discrimination threshold and a second discrimination threshold, two valid signals from the same source are processed for discrimination, and 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.

[0034] 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.

[0035] 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.

[0036] 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 comprises a filtering module, a time measurement module and a data processing module, the time measurement module is connected to the filtering module and the data processing module respectively; The filtering module is configured to receive an analog signal output by a particle detector, filter and denoise the analog signal, and convert the processed signal into two-way homologous effective signal output; The time measurement module is configured to receive the two-way homologous effective signal, configure a first discrimination threshold and a second discrimination threshold, discriminate the two-way homologous effective signal respectively, capture the characteristic time when each signal reaches the corresponding discrimination threshold, and output a first characteristic time and a second characteristic time; The data processing module is configured to calculate a high-precision arrival time based on the approximate linear characteristic of the rising edge of the signal pulse, and perform operations according to the first discrimination threshold, the second discrimination threshold, the first characteristic time and the second characteristic time.

2. The system of claim 1, wherein, The filtering module comprises a filter circuit with adjustable passband and an amplifier circuit with adjustable amplification factor; The passband range of the filter circuit covers the frequency interval 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.

3. The system of claim 2, wherein, The amplification factor of the amplifier circuit is adjusted through two-stage amplification logic, wherein the first-stage amplification logic is integrated by the filter circuit, and the second-stage amplification logic is realized by an independent amplifier circuit; The amplitude of the two-way homologous effective signal is adjusted through the two-stage amplification logic to adapt to the range requirements of the first discrimination threshold and the second discrimination threshold.

4. The system of claim 1, wherein, The time measurement module comprises a discrimination circuit and a time measurement circuit; The discrimination circuit comprises two comparators with different threshold values corresponding to the first discrimination threshold and the second discrimination threshold, respectively, for threshold comparison of the two-way homologous effective signal, and outputs two-way digital square wave signals; The time measurement circuit is configured to capture the trigger time of the two-way digital square wave signals to obtain the first characteristic time and the second characteristic time.

5. The system of claim 4, wherein, The two-way digital square wave signals output by the discrimination circuit are CMOS signals, and the time measurement circuit receives the two-way CMOS signals through two independent channels to capture the corresponding trigger time synchronously.

6. The system of claim 1, wherein, When the first discrimination threshold and the second discrimination threshold are configured, the first discrimination threshold is less than the second discrimination threshold, and both fall within a preset amplitude interval of the rising edge of the signal pulse; the preset amplitude interval is an interval in which the signal amplitude rises from 10% to 90% of the maximum amplitude.

7. The system of claim 1, wherein, The adjustable range of the first discrimination threshold and the second discrimination threshold is 0-3.3V.

8. The system of claim 1, wherein, Based on the approximate linear characteristic of the rising edge of the signal pulse, the first discrimination threshold, the second discrimination threshold, the first characteristic time and the second characteristic time are used to calculate the high-precision arrival time, which includes: Based on the approximate linear characteristic of the rising edge of the signal pulse, the first discrimination threshold, the second discrimination threshold and the corresponding characteristic time are used to deduce the time corresponding to the signal amplitude of 0 to obtain the high-precision arrival time.

9. The system of claim 1, wherein, In the operation process of the data processing module, the electronic circuit trace delay compensation parameters pre-calibrated after the system is built are integrated to offset the fixed delay error generated in the transmission process of the signals between the modules.

10. A high-precision timing method based on double-channel time measurement, characterized in that, The method comprises: Receiving an analog signal output by a particle detector, filtering and denoising the analog signal, and converting the processed signal into two-way homologous effective signal output; By configuring a first discrimination threshold and a second discrimination threshold, the two-way homologous effective signals are respectively discriminated, the characteristic moment when each signal reaches the corresponding discrimination threshold is captured, and a first characteristic moment and a second characteristic moment are output; Based on the approximate linear characteristic of the rising edge of the signal pulse, the first discrimination threshold, the second discrimination threshold, the first characteristic moment and the second characteristic moment are operated to calculate a high-precision arrival time and store it.

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