Parallel demultiplexing type photonic analog-digital conversion phase mismatch real-time feedback self-calibration method and system

Abstract

A method and system for real-time feedback self-calibration of phase mismatch in parallel demultiplexed photonic analog-to-digital conversion (ADC) systems are disclosed. This method processes and analyzes the output digital signal of an interleaved photonic ADC system, extracts phase mismatch information under system operating conditions by leveraging the characteristics of the inter-channel phase response curves, and constructs a feedback link combining a demultiplexing module and an optically adjustable delay module to achieve phase mismatch calibration. This invention overcomes the challenges of complex hardware design and cumbersome software algorithms in traditional ADC system calibration, achieving real-time feedback self-calibration without the need for external equipment. This invention is of great significance for improving the performance of time-interleaved photonic ADC systems and promoting their practical application.

Description

Technical Field

[0001] This invention relates to photonic information processing, specifically a parallel demultiplexing photonic analog-to-digital conversion phase mismatch real-time feedback self-calibration method and system. Background Technology

[0002] In the era of big data, the reception, transmission, and processing of information permeate every aspect of life. Analog-to-digital converters (ADCs), as the bridge connecting the analog and digital worlds, significantly impact the quality of signal processing. Research shows that each technological advancement in ADCs has a substantial impact on signal processing capabilities. However, limited by inherent factors such as clock jitter and comparator ambiguity, electronic ADC systems struggle to receive and process signals with larger bandwidths and higher speeds. The slowdown of Moore's Law further indicates that electronic ADC systems are approaching their performance limits. Photonic ADC systems, due to their advantages of high bandwidth, high speed, and high precision, have attracted widespread research and attention in recent years, aiming to achieve the reception and processing of broadband signals in increasingly complex electromagnetic environments.

[0003] Currently, most photonic analog-to-digital converters (A / D) overcome the sampling rate and input bandwidth limitations of single-channel A / D systems by using channel interleaving, enabling Nyquist sampling of input signals with higher frequencies and wider bandwidths. However, the non-uniformity of gain, delay, bias, and frequency response among the various sub-channels in the system can introduce numerous harmonic components into the digitally interleaved reconstructed signal, leading to distortion and aberration of the target signal and severely degrading the performance of the interleaved A / D system. Among these channel mismatch factors, compared to amplitude mismatch and bias mismatch between channels, which can be calibrated and corrected using statistical characteristics, phase mismatch introduced by system transmission delay and frequency response is highly correlated with the input signal and is difficult to extract and compensate for through calibration. Furthermore, the impact of phase mismatch on the input signal is positively correlated with the input signal frequency; therefore, systems operating in high-frequency input environments have extremely low tolerance for phase mismatch. In fact, in most interleaved A / D systems, phase mismatch plays a dominant role in affecting the overall system performance.

[0004] Most existing techniques for correcting phase mismatch in photonic analog-to-digital conversion (ADC) systems borrow from channel mismatch compensation techniques in electronic analog-to-digital conversion (ADC). In 2001, J.T. Cwichell et al. at MIT proposed a phase-encoded method for calibrating and compensating channel mismatch in photonic ADC systems; however, this method has a complex hardware structure, doubling the number of back-end channels. In 2008, Anatol Khilo et al. at MIT proposed an adaptive algorithm for error measurement in photonic ADC systems; however, this algorithm is only applicable to gain mismatch calibration and cannot compensate for phase mismatch. In 2011, Xiangming Shen et al. at Shanghai Jiao Tong University proposed a mismatch compensation algorithm based on the measurement of system sampling clock non-uniformity; however, this method faces the challenge of high-precision measurement of high-speed sampling clocks. In 2016, Yang Guang et al. extracted mismatch information between channels from the discrete spectrum using a multi-parameter Fourier transform algorithm, achieving mismatch calibration for time-wavelength interleaved photonic analog-to-digital converter (A / D) systems. However, this method has a high computational cost and cannot completely eliminate system phase mismatch (see patent publication number CN106444216). It is evident that current mismatch techniques for photonic A / D systems mostly rely on complex software algorithms and additional hardware to calibrate mismatch errors, resulting in high calibration costs and complex processes. Furthermore, since the input signal bandwidth of a photonic A / D system containing multiple channels typically spans multiple sub-channel Nyquist intervals, compared to electronic A / D systems, the factors causing phase mismatch in parallel demultiplexed photonic A / D systems include not only pulse asynchronous quantization but also additional phase deviations introduced during the demultiplexing signal loading process. This results in phase mismatch exhibiting significant frequency range characteristics in the output signal. Although some progress has been made in research on gain mismatch and bias mismatch in photonic A / D systems, no methods for calibrating phase mismatch in parallel demultiplexed photonic A / D systems have been reported in recent years. Therefore, there is an urgent need for an efficient and low-complexity real-time correction method for phase mismatch in parallel demultiplexing photonic analog-to-digital conversion systems. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a real-time feedback self-calibration method and system for phase mismatch in parallel demultiplexed photonic analog-to-digital conversion. This method is applicable to parallel demultiplexed photonic analog-to-digital conversion systems, extracting the Δt and Δt values ​​causing system phase mismatch from the digital signal output by the back-end DSP. The phase mismatch is eliminated according to its characteristics, and the system phase mismatch calibration is finally completed. Here, Δt represents the time deviation of pulse asynchronous quantization between channels. This represents the phase deviation between the demultiplexing drive signal and the pulse to be demultiplexed. Unlike traditional electronic analog-to-digital converters, this invention utilizes the frequency range characteristics of the phase frequency response curves of each channel in a parallel demultiplexing photonic analog-to-digital converter to accurately locate the position of the phase deviation. First, Δt is calibrated, and then calibrated sequentially at each level. This invention calibrates phase mismatch. During this process, the changes in the phase frequency response curves of each channel are monitored in real time using quantized spectrum, achieving high-precision feedback calibration. This invention can complete phase mismatch calibration and feedback calibration without the need for additional calibration circuits or software algorithms, greatly reducing the complexity of system control. It is of great significance for improving the performance of parallel demultiplexed photonic analog-to-digital converters and promoting the practical application of parallel demultiplexed photonic analog-to-digital converter systems.

[0006] The theoretical justification for this invention is as follows:

[0007] The parallel demultiplexing photonic analog-to-digital converter system achieves rate matching between the high-speed optical sampling front-end and the low-speed digital conversion back-end through a demultiplexing module, increasing the total sampling rate to F. s The high-speed sampling pulse sequence is demultiplexed into M channels with a sampling rate of F. s A low-speed pulse sequence to be quantized at frequency f / M. In a parallel demultiplexed optical analog-to-digital converter system with N-level demultiplexing, when the frequency of the input sampled signal is f in At that time, the output digital signal sequence after channel interleaving by the back-end data integration and processing module can be represented as:

[0008]

[0009] Where A0 is a multiplicative constant factor determined by various parameters of the system; Δt represents the phase deviation between the nth-level, mth-channel demultiplexing drive signal and the pulse to be demultiplexed; m The time deviation introduced by the asynchronous quantization of the pulses of the m-th channel and the reference channel; i is a positive integer greater than or equal to zero. Equation (1) shows that due to the influence of the two phase mismatches, the final system output signal will be distorted, and the effects of the two phase mismatches are significantly different. Figure 2(a) is a schematic diagram of the digital spectrum of the M-channel parallel demultiplexed photonic analog-to-digital converter system after interleaving under ideal conditions; Figure 2(b) is a schematic diagram of the digital spectrum of the M-channel parallel demultiplexed photonic analog-to-digital converter system with phase mismatch. Figure 2(c) is a schematic diagram of the digital spectrum of the M-channel parallel demultiplexed photonic analog-to-digital converter system with phase mismatch. m Figure 2(d) shows the frequency response curves of the inter-channel phase difference; Figure 2(d) shows the frequency response curves of the inter-channel phase difference when only the phase difference exists. The diagram shows the phase-frequency response curve. Therefore, starting from the phase-frequency response curve, phase mismatch calibration of the time-division parallel demultiplexing photonic analog-to-digital conversion system can be achieved.

[0010] The technical solution of the present invention is as follows:

[0011] On the one hand, the present invention provides a real-time feedback self-calibration method for phase mismatch in parallel demultiplexing photonic analog-to-digital conversion, characterized in that the method includes the following stages:

[0012] - The phase mismatch error extraction stage includes the following steps:

[0013] The sampled signal source and the optical sampling clock source are acquired, and the optical pulse analog signal carrying the sampled source information is obtained through the photonic sampling gate;

[0014] The demultiplexed signal is acquired, and through a multi-segment demultiplexing module, M digital signals are obtained and transmitted to the data integration and processing module.

[0015] Based on the demultiplexing rule, uniform zero-value interpolation is performed on the M-channel digital signals, and discrete Fourier transform is performed on the interpolated digital sequence to obtain the digital quantization spectrum of the m-th digital signal affected by phase mismatch.

[0016] The signal phase with the angular frequency of the aliased signal after the demultiplexing module is extracted from the M digital signals, and the phase difference between the M-1 signal phases and the first signal phase is obtained with the first signal phase as a reference, thus forming a phase frequency response curve.

[0017] Based on the phase frequency response curve, the transmission delay deviation and demultiplexing phase deviation of the m-th signal are obtained.

[0018] -The phase mismatch error feedback calibration stage includes the following steps:

[0019] The transmission delay deviation of each signal is calibrated by adjusting the adjustable delay line module;

[0020] The phase deviation of each demultiplexing unit is calibrated by adjusting the phase of the demultiplexing signal loaded in the corresponding demultiplexing unit.

[0021] The following provides a detailed explanation of the above steps:

[0022] - The phase mismatch error extraction stage includes the following steps:

[0023] S1, the parallel demultiplexing photonic analog-to-digital converter system, under the control of the demultiplexing signal, converts the external input analog signal X(t) generated by the sampled signal source into M-channel digital signals {X1[n], X2[n], ... X...}. m [n],…X M-1 [n], X M [n]}, and is transmitted into the data integration and processing module. Where X(t) is a frequency scan signal covering the Nyquist interval of the total sampling rate of the photonic analog-to-digital conversion system, X m[n] represents the m-th output digital signal, where n represents the quantized digital sequence, m = 1, 2, ..., M, n = 1, 2, ...;

[0024] S2, the data integration and processing module performs uniform zero-value interpolation on the M channels according to the demultiplexing rules of the demultiplexing module, and performs discrete Fourier transform on the resulting interpolated digital sequence. Since gain mismatch and bias mismatch can be eliminated through the statistical characteristics of the inter-channel sequences, only the effect of phase mismatch is considered here. Taking the signal after the m-th channel difference as an example, the digital quantization spectrum V of the m-th channel affected by phase mismatch is obtained. m [t];

[0025] S3, extract the phase Φ of the signal with angular frequency ω from the spectrum of the M input digital signals respectively, and take the phase Φ1[ω] of the first channel as the reference, set ΔΦ1[ω]=0, to obtain the phase difference characteristic curves {ΔΦ2[ω], ΔΦ3[ω], …ΔΦ1 ... m [ω],…ΔΦ M-1 [ω],ΔΦ M [ω]} represents the phase-frequency response curve. ΔΦ m [ω] reflects the pulse asynchrony quantization deviation Δt of each subchannel in a parallel demultiplexing photonic analog-to-digital conversion system. m Phase deviation with demultiplexing The effect on the signal phase;

[0026] S4, calculate the transmission delay deviation Δt in the m-th channel respectively. m Phase deviation with demultiplexing The calculation method is shown in equation (2):

[0027]

[0028]

[0029] in Affected by the demultiplexing module, the interval changes with the Nyquist interval in the m-th channel;

[0030] -The phase mismatch error feedback calibration stage includes the following steps:

[0031] S1, Δt is obtained from the phase mismatch error extraction stage. m Adjust the adjustable delay line module to control the inter-channel pulse asynchrony quantization delay deviation Δt. m Perform calibration. Observe the phase response curves ΔΦ of each channel in real time. m [ω], and repeat the process continuously.

[0032] S2, based on the phase mismatch error extraction stage Adjusting the phase of the radio frequency signal applied to the corresponding demultiplexing unit in the demultiplexing module to correct the demultiplexing phase deviation. Perform sequential calibration. Specifically, starting from the first-stage demultiplexing n=1 to the last-stage demultiplexing n=N, adjust the corresponding phase deviations stage by stage. Meanwhile, according to the phase difference characteristic curve ΔΦ mentioned in the phase mismatch error extraction stage... m [ω] can be used to determine the phase deviation of the demultiplexed signal. The number of multiplexing levels n that appears is adjusted accordingly. The phase response curves ΔΦ of each channel are observed in real time. m [ω], and repeat the process continuously.

[0033] On the other hand, the present invention also provides a parallel demultiplexing photonic analog-to-digital converter system with the above-mentioned real-time feedback self-calibration function for phase mismatch, characterized in that it includes:

[0034] An optical sampling clock source is used to generate an optical sampling clock and input it into an electro-optic sampling gate;

[0035] An electro-optic sampling gate is used to sample the signal from the source signal and output an analog optical pulse signal carrying the information of the sampled signal.

[0036] The demultiplexing module is used to decompose an optical pulse sequence into M optical pulse sequences under the control of the demultiplexing signal;

[0037] Adjustable delay line module, used to generate a defined optical path delay;

[0038] A photodetector is used to convert light pulse signals into electrical signals;

[0039] An electronic analog-to-digital converter is used to quantize and encode electrical signals;

[0040] The data integration and processing module is used to complete the interleaving and reconstruction of electrical and digital signals and the calculation and extraction of system phase mismatch. It then feeds the phase mismatch back to the demultiplexing module and the adjustable delay line module to complete real-time feedback self-calibration of the system phase mismatch. System phase mismatch includes the time deviation of pulse asynchronous quantization between channels, as well as the phase deviation between the demultiplexing drive signal and the pulse to be demultiplexed.

[0041] Compared with the prior art, the present invention has the following advantages:

[0042] 1. This invention proposes a calibration method for phase mismatch introduced by the demultiplexing module in a parallel demultiplexing photonic analog-to-digital conversion system. The method uses the system's digital signal output as the feedback calibration criterion and can achieve self-calibration without the aid of additional hardware devices or software algorithms, thus simplifying the calibration complexity and improving the calibration accuracy.

[0043] 2. This invention combines the phase frequency response curve characteristics of the sub-channels of the photonic analog-to-digital conversion system to calibrate the phase mismatch introduced by transmission delay deviation and demultiplexing signal deviation in stages, avoiding mutual interference between the two factors. It is particularly suitable for phase mismatch calibration of photonic analog-to-digital conversion systems.

[0044] 3. This invention achieves precise location of phase mismatch based on the digital quantization output of a parallel demultiplexing photonic analog-to-digital conversion system. Increasing the number of channels M does not increase the complexity of calibration, making the system scalable and possessing the potential for automatic control development. Attached Figure Description

[0045] Figure 1 This is the overall architecture and feedback flowchart of an embodiment of the real-time feedback self-calibration method for phase mismatch in an interleaved photonic analog-to-digital conversion system based on the present invention;

[0046] Figure 2(a) is a schematic diagram of the digital spectrum after interleaving in an M-channel interleaved photonic analog-to-digital converter system with phase mismatch; Figure 2(b) is a schematic diagram of the digital spectrum after interleaving in an M-channel interleaved system with phase mismatch calibration; Figure 2(c) is a schematic diagram of the digital spectrum after interleaving in an M-channel interleaved system with only Δt. m Figure 2(d) shows the frequency response curves of the inter-channel phase difference; Figure 2(d) shows the frequency response curves of the inter-channel phase difference when only the phase difference exists. A schematic diagram of the phase frequency response curve.

[0047] Figure 3 This is a schematic diagram of a real-time feedback self-calibration method for phase mismatch in an interleaved photonic analog-to-digital conversion system. Detailed Implementation

[0048] A specific embodiment of the present invention is given below with reference to the accompanying drawings. This embodiment is based on a real-time feedback self-calibration method and system for phase mismatch in parallel demultiplexing photonic analog-to-digital conversion. This embodiment provides detailed implementation methods and processes of the present invention, but the scope of protection of the present invention is not limited to the following embodiment.

[0049] Please see Figure 1 , Figure 1This is a diagram illustrating the overall framework of the real-time feedback self-calibration method for a parallel demultiplexed photonic analog-to-digital converter (A / D converter) system, as described in this invention. The A / D converter architecture, based on parallel photonic sampling, includes an optical sampling clock source 1 generating optical sampling pulses 1-1 using a cascaded modulator. These pulses are then sampled by an electro-optic sampling gate 2 composed of electro-optic modulators 2-1. The optical pulses carrying the sampled signal information are then demultiplexed by a demultiplexing signal 4-2, passing through a demultiplexing module 4 composed of dual-output electro-optic modulators 4-1 to obtain M outputs. These outputs are then converted into electrical signals by a photodetector 6-1 and input into an electronic analog-to-digital converter 7-1 for analog-to-digital conversion. Finally, the signals are input to a data integration and processing module 8-1 for data analysis and processing. The photodetector consists of M parallel PD units, and the electronic analog-to-digital converter consists of M parallel electronic analog-to-digital converters.

[0050] like Figure 3 The diagram illustrates a real-time feedback self-calibration method for phase mismatch in a time-interleaved photonic analog-to-digital conversion system. The specific steps of this method include:

[0051] - The phase mismatch error extraction stage includes the following steps:

[0052] S1, the parallel demultiplexing photonic analog-to-digital converter system, under the control of the demultiplexing signal 4-2, converts the external input analog signal X(t) generated by the sampled signal source 3 into M-channel digital signals {X1[n], X2[n], ... X...}. m [n],…X M-1 [n], X M [n]}, and is transmitted into the data integration and processing module 8, where X(t) is a frequency sweep signal covering the Nyquist interval fs / 2 of the total sampling rate of the photonic analog-to-digital conversion system, Xm[n] represents the m-th output digital signal, n represents the quantized digital sequence, m = 1, 2, ..., M, n = 1, 2, ...;

[0053] S2, the data integration and processing module 8 performs uniform zero-value interpolation on the M channels according to the demultiplexing rules of the demultiplexing module 4, and performs discrete Fourier transform on the resulting interpolated digital sequence. Since gain mismatch and bias mismatch can be eliminated by the statistical characteristics of the inter-channel sequences, only the effect of phase mismatch is considered here. Taking the signal after the m-th channel difference as an example, the digital quantization spectrum V of the m-th channel affected by phase mismatch is obtained. m [t];

[0054] S3, extract the phase Φ of the signal with angular frequency ω from the spectrum of the M input digital signals respectively, and take the phase Φ1[ω] of the first channel as the reference, set ΔΦ1[ω]=0, to obtain the phase difference characteristic curves {ΔΦ2[ω], ΔΦ3[ω], …ΔΦ1 ... m [ω],…ΔΦ M-1 [ω],ΔΦ M [ω]} represents the phase-frequency response curve. ΔΦ m [ω] reflects the pulse asynchrony quantization deviation Δt in each subchannel of the parallel demultiplexing photonic analog-to-digital conversion system. m Phase deviation with demultiplexing The effect on the signal phase;

[0055] S4, calculate the transmission delay deviation Δt in the m-th channel respectively. m Phase deviation with demultiplexing The calculation method is shown in equation (3):

[0056]

[0057]

[0058] in Affected by the demultiplexing module, the interval changes with the Nyquist interval in the m-th channel;

[0059] -The phase mismatch error feedback calibration stage includes the following steps:

[0060] S1, based on the transmission delay deviation Δt obtained in the phase mismatch error extraction stage. m Adjust the adjustable delay line module 5 to quantize the inter-channel pulse asynchrony delay deviation Δt. m Perform calibration. Observe the phase response curves ΔΦ of each channel in real time. m [ω], and repeat this process continuously. When the broken-line variation pattern shown in Figure 2(a) is eliminated, it can be considered that Δt m Calibration complete;

[0061] S2, Based on the multiplexed phase deviation obtained in the phase mismatch error extraction stage. Adjusting the phase of the radio frequency signal 4-2 applied to the corresponding demultiplexing unit 4-1 in the demultiplexing module 4 to correct the demultiplexing phase deviation. Perform sequential calibration. Specifically, starting from the first-stage demultiplexing n=1 to the last-stage demultiplexing n=N, adjust the corresponding phase deviations stage by stage. Meanwhile, according to the phase difference characteristic curve ΔΦ mentioned in the phase mismatch error extraction stage... m [ω] can be used to determine the phase deviation of the demultiplexed signal. The number of multiplexing levels n that appears is adjusted accordingly. The phase response curves ΔΦ of each channel are observed in real time. m [ω], and repeat this process continuously. When the step-like variation pattern shown in Figure 2(b) is eliminated, Δt can be considered as... m Calibration complete; at this point, the phase mismatch of the demultiplexed photonic analog-to-digital conversion system is fully calibrated.

[0062] The phase of the radio frequency signal 4-2 in the demultiplexing module 4 can be adjusted using, but is not limited to, an electrical phase shifter;

[0063] The data integration and processing module 8 can be, but is not limited to, FPGA or DSP.

[0064] In the above process, by step-by-step and interval-by-interval adjustment of phase mismatch in an 8-channel demultiplexed photonic analog-to-digital converter system with a total sampling rate of 40 GSa / s, the influence of system phase mismatch is effectively suppressed. The effects of phase mismatch introduced by transmission delay and demultiplexing phase deviation are calibrated separately, avoiding mutual interference between the two. At the same time, by utilizing the characteristics of the phase characteristic curve, rapid localization of system phase deviation between partitions is achieved, further reducing the complexity of debugging and improving the debugging accuracy. Based on a parallel demultiplexed photonic analog-to-digital converter system, this invention proposes a real-time feedback self-calibration method that does not require additional hardware equipment and cumbersome software algorithms. This greatly reduces the calibration complexity of system phase mismatch, improves calibration accuracy and real-time performance, and can provide a reliable technical solution for the calibration and debugging of future large-scale, multi-channel systems, thus advancing the practical application of photonic analog-to-digital converter systems.

Claims

1. A phase mismatch real-time feedback self-calibration method for a parallel demultiplexing type photonic analog-digital conversion system, characterized in that, The method includes the following stages: - Phase mismatch error extraction stage: The sampled signal source and the optical sampling clock source are acquired, and the optical pulse analog signal carrying the sampled source information is obtained through the photonic sampling gate; The demultiplexed signal is acquired, and through a multi-segment demultiplexing module, an M-channel optical pulse sequence is obtained. The M-channel optical pulse sequence is sequentially converted into electrical signals by a photodetector, then quantized into M-channel digital signals by an electronic analog-to-digital converter, and then transmitted into the data integration and processing module. Based on the demultiplexing rule, uniform zero-value interpolation is performed on the M-channel digital signals, and discrete Fourier transform is performed on the interpolated digital sequence to obtain the digital quantization spectrum of the m-th digital signal affected by phase mismatch. The signal phase with the angular frequency of the aliased signal after the demultiplexing module is extracted from the M digital signals, and the phase difference between the M-1 signal phases and the first signal phase is obtained with the first signal phase as a reference, thus forming a phase frequency response curve. Based on the phase-frequency response curve, the transmission delay deviation and demultiplexing phase deviation of the m-th digital signal are obtained, where m = 1, 2, ..., M; -Phase mismatch error feedback calibration stage: The transmission delay deviation of each signal is calibrated by adjusting the adjustable delay line module; The phase deviation of each demultiplexing unit is calibrated by adjusting the phase of the demultiplexing signal loaded in the corresponding demultiplexing unit.

2. The phase mismatch real-time feedback self-calibration method of claim 1, wherein, The optical pulse analog signal is a swept-frequency signal whose frequency range covers the Nyquist interval fs / 2 of the total sampling rate of the parallel demultiplexed photonic analog-to-digital converter system.

3. The phase mismatch real-time feedback self-calibration method of claim 1, wherein, The slope of each interval in the phase frequency response curve reflects the transmission delay deviation, the offset position reflects the number of demultiplexing stages n, and the offset magnitude reflects the magnitude of the demultiplexing phase deviation.

4. The phase mismatch real-time feedback self-calibration method of claim 1, wherein, The transmission delay deviation of the m-th digital signal and the phase mismatch spurious signal caused by the demultiplexing phase deviation are generated at the same location in the digital quantization spectrum and are independent of each other.

5. A parallel demultiplexing photonic analog-to-digital conversion system using the phase mismatch real-time feedback self-calibration method according to any one of claims 1-4, characterized in that, include: An optical sampling clock source is used to generate an optical sampling clock and input it into a photonic sampling gate; A photonic sampling gate is used to sample the signal from the sampled signal source and output a light pulse analog signal carrying the information of the sampled source. The demultiplexing module is used to decompose the optical pulse analog signal into M optical pulse sequences under the control of the demultiplexing signal; Adjustable delay line module, used to generate a defined optical path delay; A photodetector is used to convert the M-channel optical pulse sequence into an electrical signal; An electronic analog-to-digital converter is used to quantize and encode the electrical signal to obtain M digital signals; The data integration and processing module is used to complete the interleaving reconstruction of the M-channel digital signals and the calculation and extraction of the system phase mismatch. The phase mismatch is then fed back to the demultiplexing module and the adjustable delay line module to complete the real-time feedback self-calibration of the system phase mismatch. The system phase mismatch includes the time deviation of pulse asynchronous quantization between each channel and the phase deviation between the demultiplexing drive signal and the pulse to be demultiplexed.

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