Integrated optical electromagnetic pulse large dynamic range measurement system and method

Abstract

The application provides an integrated optical electromagnetic pulse large dynamic range measurement system and method, and aims to solve the technical problem that the sensor measurement dynamic range of the existing integrated optical electromagnetic pulse measurement system and method is limited and it is difficult to expand the dynamic range to a higher requirement. The application combines two monochromatic light signals into a double-color light signal through wavelength division multiplexing technology, and then inputs the double-color light signal into an integrated optical electromagnetic pulse sensor with an asymmetric structure. The wavelength of the two monochromatic light signals is adjusted so that the bias difference in the sensor is pi / 2+npi. After the to-be-measured signal is loaded as modulation information on the double-color light signal, the double-color light signal is restored into two monochromatic light signals. A voltage signal containing a direct current term is output through photoelectric conversion. According to the nonlinear interval of the transfer function of the two monochromatic light signals loaded with the modulation information, the obtained two digital voltage signals are operated to obtain the pulse waveform of the to-be-measured signal, and large dynamic range measurement is realized.

Description

Technical Field

[0001] This invention relates to electromagnetic pulse measurement, specifically to an integrated optical electromagnetic pulse large dynamic range measurement system and method. Background Technology

[0002] Integrated optical electromagnetic pulse (EMP) sensors, characterized by their small size, wide bandwidth, and strong resistance to electromagnetic interference, are an important technical means for EMP measurement. To ensure optimal performance, the bias point should be positioned as close as possible to the optimal bias point (π / 2) to keep it within the linear range, thus minimizing measurement distortion and maximizing sensitivity and dynamic range. The transfer function of an integrated EMP sensor is typically a cosine function model. Current research focuses on placing the sensor's bias point at the optimal bias point and utilizing the linear region in the neighborhood of this bias point for EMP measurement. However, the linear region of an integrated EMP sensor is only one-quarter of its half-wave signal. Beyond this linear region, the sensor output becomes distorted and fails to characterize the measured waveform.

[0003] Currently, the dynamic range of integrated optical electromagnetic pulse (OEM) sensors is mainly extended through two technical means: first, by reducing output noise to extend the lower limit of signal measurement; second, by utilizing the nonlinear region of the monotonic interval to calculate and recover the signal under test based on the transfer function, thereby increasing the upper limit of signal measurement. However, since the output noise of integrated OEM sensors mainly originates from the laser, and laser noise is already at a relatively low level, further reduction is difficult. Therefore, the industry currently mainly uses the second method to extend the dynamic range of integrated OEM sensors. However, since the maximum monotonic interval of the transfer function of an integrated OEM sensor is half that of a half-wave signal, the dynamic range of the sensor is limited when using this method. That is, the upper limit of sensor measurement can only be increased by a maximum of 100%, making it difficult to extend the dynamic range to meet higher requirements. Summary of the Invention

[0004] The purpose of this invention is to solve the technical problem that the dynamic range of the sensor in existing integrated optical electromagnetic pulse measurement systems and methods is limited, making it difficult to extend the dynamic range to meet higher requirements. In this invention, we provide an integrated optical electromagnetic pulse large dynamic range measurement system and method.

[0005] To achieve the above objectives, the present invention provides the following technical concept:

[0006] An integrated optical electromagnetic pulse sensor based on an asymmetric optical path structure combines two monochromatic light signals into a dual-color light signal using wavelength division multiplexing (WDM) technology, which is then input into the sensor. The wavelengths of the two monochromatic light signals are adjusted so that their bias difference within the sensor is π / 2 + nπ. The signal to be measured is then loaded as modulation information onto the dual-color light signal, and WDM is used again to recover the dual-color light signal into two monochromatic light signals. A voltage signal containing a DC term is output through photoelectric conversion. Based on the nonlinear range of the transfer function of the two monochromatic light signals loaded with modulation information, the two digital voltage signals are processed to obtain the pulse waveform of the signal to be measured, thus achieving a large dynamic range measurement.

[0007] Based on this, the technical solution provided by the present invention is as follows:

[0008] An integrated optical electromagnetic pulse large dynamic range measurement system is characterized by comprising a first light source, a second light source, a first wavelength division multiplexer, a sensor, a second wavelength division multiplexer, a first photodetector, a second photodetector, an analog-to-digital converter, and a data processing unit.

[0009] The first light source and the second light source are wavelength-tunable monochromatic light sources; the first light source and the second light source are respectively connected to the two input terminals of the first wavelength division multiplexer through polarization-maintaining optical fibers, which are used to combine the two monochromatic light signals emitted by the first light source and the second light source into a dual-color light signal through the first wavelength division multiplexer;

[0010] The sensor is an integrated optical electromagnetic pulse sensor, and the modulation device in the sensor is an asymmetric modulation device. The first input terminal of the sensor is connected to the output terminal of the first wavelength division multiplexer, which is used to enable the two-color light signal to form an asymmetric modulation optical path through the asymmetric modulation device. The second input terminal of the sensor is used to receive the signal to be measured, load the signal to be measured onto the asymmetric modulation optical path, so that the signal to be measured is modulated into an optical signal and loaded onto the two-color light signal to form a two-color light signal loaded with modulation information.

[0011] The input of the second wavelength division multiplexer is connected to the output of the sensor, and is used to divide the two-color light signal loaded with modulation information into two monochromatic light signals.

[0012] The input terminals of the first and second photodetectors are respectively connected to the two output terminals of the second wavelength division multiplexer, which are used to output the two received monochromatic light signals as corresponding DC voltage signals.

[0013] The two input terminals of the analog-to-digital converter are respectively connected to the output terminals of the first and second photodetectors, and are used to convert the two DC voltage signals into digital voltage signals.

[0014] The input terminal of the data processing unit is connected to the output terminal of the analog-to-digital converter. It is used to perform calculations on the two obtained digital voltage signals based on the nonlinear range of the transfer function of the two monochromatic light signals loaded with modulation information, so as to obtain the pulse waveform of the signal under test.

[0015] Furthermore, the method steps for the data processing unit to perform calculations on the two obtained digital voltage signals based on the nonlinear interval of the transfer function of the two monochromatic light signals loaded with modulation information are as follows:

[0016] Step a, let the arrival time of the signal to be measured be t0, that is, the initial sampling time be t0. Then the amplitude demodulated value f(t0) of the signal to be measured output at the initial sampling time is:

[0017]

[0018] In the above formula:

[0019] V1(t0) and V2(t0) are the output voltages of the two monochromatic light signals at time t0, respectively;

[0020] k1 and k2 are the saturation output voltages of the first and second photodetectors, respectively.

[0021] Step b, starting from the initial sampling time t0, recursively calculates the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times using the following formula:

[0022]

[0023] In the above formula, f(t) is the amplitude demodulated value of the signal under test output at time t;

[0024] V1(t) and V2(t) are the output voltages of the two monochromatic light signals at time t, respectively;

[0025] Δt is the time interval between two adjacent sampling times;

[0026] round indicates rounding to the nearest whole number;

[0027] Step c: Obtain the initial demodulated waveform F(t) of the signal under test based on the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times;

[0028] Step d: Calculate the pulse waveform S(t) of the signal to be measured using the following formula:

[0029]

[0030] In the above formula, S π It is a half-wave signal.

[0031] Furthermore, before step d, the method also includes a step of removing the bias of the initial demodulated waveform F(t) of the signal under test;

[0032] Alternatively, after step d, a step of removing the bias of the pulse waveform S(t) of the signal under test may be included.

[0033] Furthermore, the sensor is an asymmetric Mach-Zehnder interferometer or an asymmetric bulk electro-optic modulation structure.

[0034] Furthermore, the first light source and the second light source are polarized narrow-spectrum light sources.

[0035] Furthermore, the sensor is a voltage-type sensor, an electric field-type sensor, or a current-type sensor.

[0036] This invention also proposes an integrated optical electromagnetic pulse large dynamic range measurement method, which is characterized by including the following steps:

[0037] Step 1: Construct the above-mentioned integrated optical electromagnetic pulse large dynamic range measurement system;

[0038] Step 2: The two monochromatic light signals emitted by the first light source and the second light source are transmitted to the first wavelength division multiplexer through polarization-maintaining fiber, and the two monochromatic light signals are combined into a two-color light signal by the first wavelength division multiplexer; at the same time, the wavelengths of the two monochromatic light signals are adjusted so that the difference between the natural bias points of the corresponding two monochromatic light signals in the sensor is π / 2+nπ, where n is an integer.

[0039] Step 3: The dual-color light signal is passed through the asymmetric modulation device in the sensor to form an asymmetric modulation optical path; simultaneously, the signal to be measured is input into the sensor and loaded onto the asymmetric modulation optical path, converting the dual-color light signal into a dual-color light signal with modulation information; the dual-color light signal with modulation information is transmitted through polarization-maintaining fiber to the second wavelength division multiplexer, which recovers the dual-color light signal with modulation information into two monochromatic light signals with modulation information; the two monochromatic light signals with modulation information are output as two DC voltage signals by the first photodetector and the second photodetector, respectively; the two DC voltage signals are converted into two digital voltage signals by the analog-to-digital converter and then input into the data processing unit.

[0040] Step 4: The data processing unit performs calculations on the two obtained digital voltage signals based on the nonlinear range of the transfer functions of the two monochromatic light signals loaded with modulation information, to obtain the pulse waveform of the signal under test, specifically:

[0041] Step 4.1, let the arrival time of the signal under test be t0, that is, the initial sampling time be t0. Then the amplitude demodulated value f(t0) of the signal under test output at the initial sampling time is:

[0042]

[0043] In the above formula:

[0044] V1(t0) and V2(t0) are the output voltages of the two monochromatic light signals at time t0, respectively;

[0045] k1 and k2 are the saturation output voltages of the first and second photodetectors, respectively.

[0046] Step 4.2, starting from the initial sampling time t0, the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times can be obtained according to the following formula:

[0047]

[0048] In the above formula, f(t) is the amplitude demodulated value of the signal under test output at time t;

[0049] V1(t) and V2(t) are the output voltages of the two monochromatic light signals at time t, respectively;

[0050] Δt is the time interval between two adjacent sampling times;

[0051] round indicates rounding to the nearest whole number;

[0052] Step 4.3: Based on the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times, obtain the initial demodulated waveform F(t) of the signal under test;

[0053] Step 4.4, calculate the pulse waveform S(t) of the signal to be measured using the following formula:

[0054]

[0055] In the above formula, S π It is a half-wave signal.

[0056] Furthermore, before step 4.4, the method also includes a step of removing the bias of the initial demodulated waveform F(t) of the signal under test;

[0057] Alternatively, after step 4.4, the method may include the step of removing the bias of the pulse waveform S(t) of the signal under test.

[0058] The advantages of this invention compared to the prior art are as follows:

[0059] 1. The present invention provides an integrated optical electromagnetic pulse large dynamic range measurement system. Compared with existing measurement systems, it eliminates the filter and requires that the outputs of the first and second photodetectors contain a DC term, i.e., the output is a DC voltage signal. Then, based on the nonlinear range of the transfer function of the two monochromatic light signals loaded with modulation information, the two obtained digital voltage signals are processed to obtain the pulse waveform of the signal under test. The present invention combines the dual-wavelength phase demodulation method with the integrated optical electromagnetic pulse sensor, and realizes the recovery of the nonlinear non-monotonic range of the signal under test through the DC voltage signal output by the dual channels. That is, the large dynamic range measurement of the integrated optical electromagnetic pulse is realized through the phase compensation method, which expands the measurement performance of the integrated optical electromagnetic pulse detector in environments such as high-altitude electromagnetic pulse, lightning electromagnetic pulse, and ultra-wideband.

[0060] 2. This invention provides an integrated optical electromagnetic pulse large dynamic range measurement method. By adjusting the wavelength difference between two monochromatic light signals, the natural bias difference formed in the sensor is π / 2 + nπ. Then, the digital voltage signals output from the two monochromatic light signals with modulation information are sent to the data processing unit. Based on the nonlinear range of the transfer function of the two monochromatic light signals with modulation information, the obtained two digital voltage signals are processed to obtain the pulse waveform of the signal under test. This greatly expands the dynamic range of existing measurement methods, extending its measurement upper limit to more than one order of magnitude. This invention fully utilizes the nonlinear, non-monotonic range of the integrated optical electromagnetic pulse sensor to demodulate the signal, and has important application value in fields such as high-altitude electromagnetic pulse (HEMP), lightning electromagnetic pulse (LEMP), ultra-wideband (UWB), high-power microwave (HPM), and electromagnetic compatibility (EMC). Attached Figure Description

[0061] Figure 1 This is a structural block diagram of an embodiment of an integrated optical electromagnetic pulse large dynamic range measurement system of the present invention (data processing unit not shown).

[0062] The specific labeling in the attached diagram is as follows:

[0063] 1-First light source; 2-Second light source; 3-First wavelength division multiplexer; 4-Sensor; 5-Second wavelength division multiplexer; 6-First photodetector; 7-Second photodetector; 8-Analog-to-digital converter. Detailed Implementation

[0064] To make the advantages and features of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0065] like Figure 1As shown, an integrated optical electromagnetic pulse large dynamic range measurement system includes a first light source 1, a second light source 2, a first wavelength division multiplexer 3, a sensor 4, a second wavelength division multiplexer 5, a first photodetector 6, a second photodetector 7, an analog-to-digital converter 8, and a data processing unit.

[0066] The first light source 1 and the second light source 2 are wavelength-tunable monochromatic light sources. Preferably, in this embodiment, a polarization narrow-spectrum light source is used. The first light source 1 and the second light source 2 are respectively connected to the two input terminals of the first wavelength division multiplexer 3 through polarization-maintaining optical fibers, which are used to combine the two monochromatic light signals emitted by the first light source 1 and the second light source 2 into a dual-color light signal through the first wavelength division multiplexer 3.

[0067] Sensor 4 is an integrated optical electromagnetic pulse sensor. The modulation device in the integrated optical electromagnetic pulse sensor is an asymmetric modulation device, such as an asymmetric Mach-Zehnder interferometer or an asymmetric bulk electro-optic modulation structure. The first input terminal of sensor 4 is connected to the output terminal of the first wavelength division multiplexer 3, which is used to enable the two-color light signal to form an asymmetric modulation optical path through the asymmetric modulation device in sensor 4. Since the bias point of the integrated optical electromagnetic pulse sensor is related to the input light signal, two monochromatic light signals of different wavelengths will produce different bias points under the influence of the asymmetric modulation optical path. Therefore, adjusting the wavelength difference between the two monochromatic light signals can change the difference between the natural bias points corresponding to the two monochromatic light signals in sensor 4. In this invention, the difference between the natural bias points corresponding to the two monochromatic light signals is set to π / 2 + nπ, where n is an integer. The second input terminal of sensor 4 is used to receive the signal to be measured and load the signal to be measured onto the asymmetric modulation optical path, so that the signal to be measured is modulated into an optical signal and loaded onto the two-color light signal to form a two-color light signal loaded with modulation information. In this invention, sensor 4 can be a voltage sensor, an electric field sensor, or a current sensor. The signal to be measured can be an electric field signal or an electromagnetic signal. In this embodiment, a voltage sensor is used, and the received signal to be measured is an electric field signal.

[0068] The input of the second wavelength division multiplexer 5 is connected to the output of the sensor 4, and is used to divide the two-color light signal loaded with modulation information into two monochromatic light signals. The inputs of the first photodetector 6 and the second photodetector 7 are respectively connected to the two outputs of the second wavelength division multiplexer 5, and are used to output the two received monochromatic light signals as corresponding DC voltage signals. The two inputs of the analog-to-digital converter 8 are respectively connected to the outputs of the first photodetector 6 and the second photodetector 7, and are used to convert the two DC voltage signals into digital voltage signals.

[0069] The input terminal of the data processing unit is connected to the output terminal of the analog-to-digital converter 8. It is used to perform calculations on the two obtained digital voltage signals based on the nonlinear range of the transfer function of the two monochromatic light signals loaded with modulation information, so as to obtain the pulse waveform of the signal under test.

[0070] Specifically, the method steps for the data processing unit of the present invention to perform calculations on the two obtained digital voltage signals based on the nonlinear interval of the transfer function of the two monochromatic light signals loaded with modulation information are as follows:

[0071] Step a, let the arrival time of the signal to be measured be t0, that is, the initial sampling time be t0. Then the amplitude demodulated value f(t0) of the signal to be measured output at the initial sampling time is:

[0072]

[0073] In the above formula:

[0074] V1(t0) and V2(t0) are the output voltages of the two monochromatic light signals at time t0, respectively;

[0075] k1 and k2 are the saturation output voltages of the first photodetector 6 and the second photodetector 7, respectively.

[0076] Step b, starting from the initial sampling time t0, recursively calculates the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times using the following formula:

[0077]

[0078] In the above formula, f(t) is the amplitude demodulated value of the signal under test output at time t;

[0079] V1(t) and V2(t) are the output voltages of the two monochromatic light signals at time t, respectively, and are time-domain waveforms over a period of time.

[0080] Δt is the time interval between two adjacent sampling times;

[0081] round indicates rounding to the nearest whole number;

[0082] Step c: Obtain the initial demodulated waveform F(t) of the signal under test based on the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times;

[0083] Step d: Calculate the pulse waveform S(t) of the signal to be measured using the following formula:

[0084]

[0085] In the above formula, S π It is a half-wave signal.

[0086] The derivation of the above formula is as follows:

[0087] The input-output model, i.e., the transfer function, of the measurement system of this invention is:

[0088]

[0089] In the above formula, and St represents the bias values ​​at two natural bias points formed by the two monochromatic light signals in sensor 4; S(t) is the amplitude of the signal under test at time t. Within a time interval, S represents the time-domain waveform; t represents time. π The half-wave signal value represents the external signal required to change the phase difference of the interference optical path of sensor 4 by one π.

[0090] Theoretically, when the transfer function of a sensor is known, the measurement result of the signal to be measured can be recovered based on the sensor's transfer function. When a single-beam optical signal is input, according to the sensor's input-output relationship, when the bias value of the bias point formed by the single-beam optical signal in the sensor is π / 2, the sensor's transfer function only changes at -S. π / 2 to S π Monotonic within the range of / 2, and when the amplitude of a single beam of light signal approaches S π At / 2, the output signal increases very slowly. When the output signal is subjected to a small-amplitude disturbance, the demodulated input signal will fluctuate greatly. Therefore, the signal range for single-beam optical signal measurement can only be limited to -S. π / 2 to S π Within a range of / 2. When using dual-wavelength optical signals for measurement, since the transfer function of the measurement system becomes a system of equations, the amplitude of the signal under test can be recovered based on the voltage outputs corresponding to the two optical signals in both the monotonic and non-monotonic intervals.

[0091] In the non-monotonic interval, when the difference in the natural bias points of the two monochromatic light signals in sensor 4 is π / 2 + nπ, that is... When the transfer function is as follows:

[0092]

[0093] According to formula (5), we can obtain:

[0094]

[0095] In formula (6),

[0096]

[0097] Through the above processing, the transfer function is corrected from a sine / cosine function to a tangent function. Unlike transfer functions in sine or cosine form, the transfer function in tangent form exhibits periodic monotonic characteristics.

[0098] By solving equation (7) using the arctangent function, f[S(t)] can be obtained as follows:

[0099]

[0100] when When n takes any integer value, the signal under test is in a monotonic interval. It can be seen that as the amplitude S(t) of the signal under test increases, the transfer function of the measurement system exhibits periodic monotonicity.

[0101] When the amplitude of the signal under test is sufficiently small, f[S(t)] is limited to between -π / 2 and π / 2, and can be obtained by directly setting n to 0. However, as the amplitude of the signal under test gradually increases, its amplitude may exceed a certain monotonic period. At this time, the demodulation result with n set to 0 cannot represent the input signal, and the calculation result will show a jump. Therefore, this invention uses an algorithm to superimpose bias signals on different monotonic intervals to compensate for signal abrupt changes and make the waveform continuous.

[0102] During measurement, the output is a discrete signal. When the sampling rate is high enough, the amplitude change between two adjacent sampled signals is small and there will be no abrupt change. Based on this, by changing the value of n, the calculated f[S(t)] is periodically shifted until the amplitude difference between the calculated result and the previous sampled signal reaches its minimum. This allows the amplitude demodulation value of the electromagnetic pulse of the signal under test to be obtained. By iterating in this way, the amplitude demodulation value of the signal under test at different times can be obtained, thereby reconstructing the complete pulse waveform of the signal under test.

[0103] Specifically, if we express f as a function of time t, then we have

[0104] f(t)=f[S(t)] (9)

[0105] If the output signal is sampled once at time t, and the time interval between two adjacent samples is Δt, then the amplitude demodulated value f(t+Δt) of the signal under test obtained at the next sample is:

[0106]

[0107] set up

[0108]

[0109] Then we have:

[0110] f(t+Δt)=g(t+Δt)+nπ(12)

[0111] The difference Δf between f(t+Δt) and f(t) obtained from two consecutive samplings is:

[0112] Δf=f(t+Δt)-f(t)=g(t+Δt)-f(t)+nπ (13)

[0113] The expression g(t+Δt)-f(t) can be represented in the following form:

[0114] g(t+Δt)-f(t)=mπ+a(14)

[0115] Where m is the integer obtained by rounding the quotient of g(t+Δt)-f(t) and π, and a is the remainder. That is:

[0116]

[0117] Since m is the integer value after rounding, the absolute value of a must be less than π / 2. For example, in 3.2π = 3π + 0.2π, m is 3 and a is 0.2π; in 4.7π = 5π - 0.3π, m is 5 and a is -0.3π. The absolute values ​​of 0.3π and 0.2π are both less than π / 2.

[0118] According to formulas (13) and (14), we can obtain:

[0119] Δf=f(t+Δt)-f(t)=(m+n)π+a(16)

[0120] Given that m and n are both integers, Δf must reach its minimum absolute value a when m + n = 0. Substituting this into formula (13) yields:

[0121] a=g(t+Δt)-f(t)+nπ (17)

[0122] The possible values ​​of n are:

[0123]

[0124] Before the signal to be measured arrives, f(S) takes the value of set up The value range is -π / 2 to -π / 2, used for demodulating the signal under test. Let the starting time of the measured signal be t0, i.e., the initial sampling time be t0, then:

[0125]

[0126] Based on formulas (8) and (18), we can obtain:

[0127]

[0128] because Assuming no change in a short period, formula (20) differs from the true value by only a constant. Based on formulas (19) and (20), starting from the initial sampling time t0, the amplitude demodulated values ​​of the signal under test at all sampling times can be obtained. Then, based on the amplitude demodulated values ​​of the signal under test at all sampling times, the initial demodulated waveform of the signal under test can be obtained. Clearly, the amplitude demodulated values ​​of the signal under test at all sampling times differ from its true value by the same constant. Considering that the initial value of the signal under test is 0, this embodiment performs bias removal by high-pass filtering on the obtained initial demodulated waveform of the signal under test, thereby obtaining the pulse waveform of the signal under test. In other embodiments of the present invention, bias removal can also be performed after obtaining the pulse waveform of the signal under test, and other existing methods can also be used for bias removal.

[0129] According to formula (7), the initial demodulated waveform F(t) of the signal under test is:

[0130]

[0131] Therefore, the pulse waveform S(t) of the demodulated signal under test is:

[0132]

[0133] This invention also provides an integrated optical electromagnetic pulse large dynamic range measurement method, specifically including the following steps:

[0134] Step 1: Build the integrated optical electromagnetic pulse large dynamic range measurement system described above.

[0135] Step 2: The two monochromatic light signals emitted by the first light source 1 and the second light source 2 are transmitted to the first wavelength division multiplexer 3 through polarization-maintaining optical fibers, respectively. The first wavelength division multiplexer 3 combines the two monochromatic light signals into a dual-color light signal. At the same time, the wavelengths of the two monochromatic light signals are adjusted so that the difference in the natural bias points of the corresponding two monochromatic light signals in the sensor 4 is π / 2 + nπ, where n is an integer.

[0136] Step 3: The dual-color light signal forms an asymmetric modulation optical path through the asymmetric modulation device in sensor 4. Simultaneously, the signal to be measured is input into sensor 4 and loaded onto the asymmetric modulation optical path, converting the dual-color light signal into a dual-color light signal with modulation information. The dual-color light signal with modulation information is transmitted through polarization-maintaining fiber to the second wavelength division multiplexer 5, which recovers the dual-color light signal with modulation information into two monochromatic light signals with modulation information. The two monochromatic light signals with modulation information are output as two DC voltage signals through the first photodetector 6 and the second photodetector 7, respectively. The two DC voltage signals are converted into two digital voltage signals by the analog-to-digital converter 8 and then input into the data processing unit.

[0137] Step 4: The data processing unit performs calculations on the two obtained digital voltage signals based on the nonlinear range of the transfer functions of the two monochromatic light signals loaded with modulation information, to obtain the pulse waveform of the signal under test, specifically:

[0138] Step 4.1, let the arrival time of the signal under test be t0, that is, the initial sampling time be t0. Then the amplitude demodulated value f(t0) of the signal under test output at the initial sampling time is:

[0139]

[0140] In the above formula:

[0141] V1(t0) and V2(t0) are the output voltages of the two monochromatic light signals at time t0, respectively;

[0142] k1 and k2 are the saturation output voltages of the first photodetector 6 and the second photodetector 7, respectively.

[0143] Step 4.2, starting from the initial sampling time t0, the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times can be obtained according to the following formula:

[0144]

[0145] In the above formula, f(t) is the amplitude demodulated value of the signal under test output at time t;

[0146] V1(t) and V2(t) are the output voltages of the two monochromatic light signals at time t, respectively, and are time-domain waveforms over a period of time.

[0147] Δt is the time interval between two adjacent sampling times;

[0148] round indicates rounding to the nearest whole number;

[0149] Step 4.3: Based on the amplitude demodulation value f(t+Δt) of the signal under test at all sampling times, obtain the initial demodulated waveform F(t) of the signal under test;

[0150] Step 4.4: Remove the bias of the initial demodulated waveform F(t) of the signal under test, and calculate the pulse waveform S(t) of the signal under test using the following formula:

[0151]

[0152] In the above formula, S π It is a half-wave signal.

[0153] The large dynamic range measurement system and method provided by this invention can theoretically measure infinitely large signals. However, considering the actual insulation performance of the sensor, it can measure signals at least five times larger than half-wave signals. Compared with existing measurement systems and methods, the measurement upper limit is extended by at least one order of magnitude.

[0154] The above description is only used to illustrate the technical solutions of the present invention, and is not intended to limit them. For those skilled in the art, modifications can be made to the specific technical solutions described in the above embodiments, or equivalent substitutions can be made to some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions protected by the present invention.

Claims

1. An integrated optical electromagnetic pulse large dynamic range measurement system, characterized in that: It includes a first light source (1), a second light source (2), a first wavelength division multiplexer (3), a sensor (4), a second wavelength division multiplexer (5), a first photodetector (6), a second photodetector (7), an analog-to-digital converter (8), and a data processing unit; The first light source (1) and the second light source (2) are monochromatic light sources with adjustable wavelengths; the first light source (1) and the second light source (2) are respectively connected to the two input ends of the first wavelength division multiplexer (3) through polarization-maintaining optical fibers, and are used to combine the two monochromatic light signals emitted by the first light source (1) and the second light source (2) into a dual-color light signal through the first wavelength division multiplexer (3); The sensor (4) is an integrated optical electromagnetic pulse sensor, and the modulation device in the sensor (4) is an asymmetric modulation device. The first input terminal of the sensor (4) is connected to the output terminal of the first wavelength division multiplexer (3) to enable the two-color light signal to form an asymmetric modulation optical path through the asymmetric modulation device. The second input terminal of the sensor (4) is used to receive the signal to be measured, load the signal to be measured onto the asymmetric modulation optical path, so that the signal to be measured is modulated into an optical signal and loaded onto the two-color light signal to form a two-color light signal loaded with modulation information. The input of the second wavelength division multiplexer (5) is connected to the output of the sensor (4) and is used to divide the two-color light signal loaded with modulation information into two monochromatic light signals. The input terminals of the first photodetector (6) and the second photodetector (7) are respectively connected to the two output terminals of the second wavelength division multiplexer (5) to output the two received monochromatic light signals as corresponding DC voltage signals. The two input terminals of the analog-to-digital converter (8) are respectively connected to the output terminals of the first photodetector (6) and the second photodetector (7) to convert the two DC voltage signals into digital voltage signals. The input end of the data processing unit is connected to the output end of the analog-to-digital converter (8), and is used to perform calculations on the two digital voltage signals obtained according to the nonlinear range of the transfer function of the two monochromatic light signals loaded with modulation information, so as to obtain the pulse waveform of the signal to be measured. The method steps for the data processing unit to perform calculations on the two obtained digital voltage signals based on the nonlinear interval of the transfer function of the two monochromatic light signals loaded with modulation information are as follows: Step a, let the arrival time of the signal to be measured be t0, that is, the initial sampling time be t0, then the amplitude demodulated value of the signal to be measured output at the initial sampling time is... for: ； In the above formula: V1(t0) and V2(t0) are the output voltages of the two monochromatic light signals at time t0, respectively; k1 and k2 are the saturation output voltages of the first photodetector (6) and the second photodetector (7), respectively; Step b: Starting from the initial sampling time t0, recursively calculate the amplitude demodulation value of the signal under test at all sampling times according to the following formula. : ； In the above formula, f(t) is the amplitude demodulated value of the signal under test output at time t; V1(t) and V2(t) are the output voltages of the two monochromatic light signals at time t, respectively; Δt is the time interval between two adjacent sampling times; round indicates rounding to the nearest whole number; Step c, based on the amplitude demodulation values ​​of the signal under test at all sampling times. Obtain the initial demodulated waveform of the signal under test. ; Step d: Calculate the pulse waveform of the signal under test using the following formula. : ； In the above formula, S π It is a half-wave signal.

2. The integrated optical electromagnetic pulse large dynamic range measurement system according to claim 1, characterized in that: Before step d, the process also includes removing the initial demodulated waveform of the signal under test. The steps of biasing; Alternatively, after step d, the pulse waveform of the signal to be measured may be removed. The steps of biasing.

3. The integrated optical electromagnetic pulse large dynamic range measurement system according to claim 2, characterized in that: The sensor (4) is an asymmetric Mach-Zehnder interferometer or an asymmetric bulk electro-optic modulation structure.

4. The integrated optical electromagnetic pulse large dynamic range measurement system according to claim 3, characterized in that: The first light source (1) and the second light source (2) are polarized narrow-spectrum light sources.

5. An integrated optical electromagnetic pulse large dynamic range measurement system according to any one of claims 1-4, characterized in that: The sensor (4) is a voltage sensor, an electric field sensor, or a current sensor.

6. A method for measuring the large dynamic range of integrated optical electromagnetic pulses, characterized in that, Includes the following steps: Step 1: Construct an integrated optical electromagnetic pulse large dynamic range measurement system as described in any one of claims 1-5; Step 2: The two monochromatic light signals emitted by the first light source (1) and the second light source (2) are transmitted to the first wavelength division multiplexer (3) through polarization-maintaining fiber, and the two monochromatic light signals are combined into a dual-color light signal by the first wavelength division multiplexer (3); at the same time, the wavelengths of the two monochromatic light signals are adjusted so that the difference between the natural bias points of the two monochromatic light signals in the sensor (4) is π / 2+nπ, where n is an integer. Step 3: The two-color light signal forms an asymmetric modulation optical path through the asymmetric modulation device in the sensor (4); at the same time, the signal to be measured is input into the sensor (4), and the signal to be measured is loaded on the asymmetric modulation optical path, so that the two-color light signal is converted into a two-color light signal with modulation information. The dual-color light signal with modulation information is transmitted to the second wavelength division multiplexer (5) through the polarization-maintaining fiber. The second wavelength division multiplexer (5) restores the dual-color light signal with modulation information into two monochromatic light signals with modulation information. Two monochromatic light signals with modulation information are output as two DC voltage signals through the first photodetector (6) and the second photodetector (7), respectively; the two DC voltage signals are converted into two digital voltage signals by the analog-to-digital converter (8) and then input into the data processing unit. Step 4: The data processing unit performs calculations on the two obtained digital voltage signals based on the nonlinear range of the transfer functions of the two monochromatic light signals loaded with modulation information, to obtain the pulse waveform of the signal under test, specifically: Step 4.1, let the arrival time of the signal under test be t0, that is, the initial sampling time be t0, then the amplitude demodulated value of the signal under test output at the initial sampling time is... for: ； In the above formula: V1(t0) and V2(t0) are the output voltages of the two monochromatic light signals at time t0, respectively; k1 and k2 are the saturation output voltages of the first photodetector (6) and the second photodetector (7), respectively; Step 4.2: Starting from the initial sampling time t0, the amplitude demodulated value of the signal under test at all sampling times can be obtained by recursion using the following formula. : ； In the above formula, f(t) is the amplitude demodulated value of the signal under test output at time t; V1(t) and V2(t) are the output voltages of the two monochromatic light signals at time t, respectively; Δt is the time interval between two adjacent sampling times; round indicates rounding to the nearest whole number; Step 4.3, demodulate the amplitude of the signal under test based on the amplitude values ​​at all sampling times. Obtain the initial demodulated waveform of the signal under test. ; Step 4.4: Calculate the pulse waveform of the signal under test using the following formula. : ； In the above formula, S π It is a half-wave signal.

7. The integrated optical electromagnetic pulse large dynamic range measurement method according to claim 6, characterized in that... Before step 4.4, the process also includes removing the initial demodulated waveform of the signal under test. The steps of biasing; Alternatively, after step 4.4, the step may include: removing the pulse waveform of the signal under test. The steps of biasing.

Images