A microwave multi-dimensional parameter measurement system and method based on differential frequency-time mapping

Abstract

The application discloses a microwave multi-dimensional parameter measurement system and method based on differential frequency-time mapping. In the system, after optical pulses pass through an input end dispersion medium to complete pulse expansion, the optical pulses enter a Sagnac loop. Meanwhile, after a microwave signal to be measured is branched by a radio frequency power divider, the microwave signal to be measured is input into two Mach-Zehnder modulators in the loop to modulate the optical pulses. An adjustable optical delay line is arranged between the first Mach-Zehnder modulator and an optical coupler. The modulated optical pulses output by the loop pass through an output end dispersion medium to realize frequency-time mapping, and map the spectrum information to the time domain. After the optical signal is converted into an electric signal by a photoelectric detector, the electric signal is converted into a digital signal by an analog-to-digital converter and is input into a digital signal processor, so that the time, frequency, amplitude and phase information of the microwave signal to be measured are obtained. The application avoids the problems of narrow bandwidth, high loss and poor adjustability of an electronic delay line, and can simultaneously perform high-precision measurement on the time, frequency, amplitude and phase of a multi-carrier microwave signal.

Description

Technical Field

[0001] This invention belongs to the field of microwave photonic signal processing technology, specifically relating to a microwave multidimensional parameter measurement system and method based on differential frequency-time mapping. Background Technology

[0002] Real-time measurement of microwave signal time-frequency amplitude-phase parameters is crucial for sensing complex electromagnetic environments, modern radar signal analysis, and next-generation communication systems. A signal's complete information can be characterized by parameters such as its frequency, amplitude, phase, and pulse period. The joint and rapid acquisition of these parameters is fundamental to achieving accurate signal identification, jamming countermeasures, and high-dimensional information extraction. Especially for low-probability intercepted burst pulse signals, their parameters often change rapidly, making it difficult for traditional discrete measurement methods to achieve a comprehensive characterization while maintaining real-time performance.

[0003] Traditional electronic measurement methods are limited by instantaneous bandwidth, sampling rate, and anti-interference capabilities, posing significant challenges in ultra-wideband and complex electromagnetic environments. Microwave photonics technology, with its inherent advantages of wide bandwidth, low loss, and electromagnetic interference resistance, offers a new approach to overcoming these bottlenecks. In the field of photon-assisted measurement of multi-dimensional parameters (time, frequency, amplitude, and phase) of microwave signals, numerous schemes have been proposed. Early schemes, such as photonic time stretching, photonic channelization, and photonic compressed sensing, primarily alleviate the pressure on back-end electronic analog-to-digital conversion through photonic preprocessing. While this expands the processing bandwidth, the final extraction of multi-dimensional information still heavily relies on complex digital post-processing. To pursue even more precise real-time response, photonic instantaneous frequency measurement technology emerged. Through frequency-power mapping, it can directly acquire multiple parameters such as frequency and pulse width without high-speed sampling. However, its inherent mapping mechanism struggles to handle simultaneous multi-carrier signals, limiting its applicability in complex spectral environments. Subsequently, optical real-time Fourier transform technology utilizes dispersive media to map the spectrum to the time domain, enabling instantaneous analysis of multi-carrier signals. However, its key performance bottleneck lies in frequency resolution, which limits its ability to capture instantaneous phase changes and complex modulation formats. Recently, an improved scheme based on polarization-multiplexed dual-channel interferometry has successfully mapped phase information to interference amplitude, enabling real-time measurement of frequency, amplitude, pulse width, pulse period, and even modulation format identification, significantly improving the information dimension of a single measurement. However, this scheme requires an additional RF cable in one branch to achieve controllable delay when implementing dual-channel interferometry. The RF cable not only introduces insertion loss, but its frequency-dependent delay characteristics also distort the phase relationship of broadband signals, fundamentally limiting the system's operating bandwidth and measurement accuracy.

[0004] To better and more comprehensively analyze microwave signal parameters and ensure the large bandwidth and accuracy of parameter measurements, improvements are needed to address the aforementioned technical issues. Summary of the Invention

[0005] In view of the above-mentioned shortcomings in the existing technology, the present invention provides a microwave multidimensional parameter measurement system and method based on differential frequency-time mapping.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution:

[0007] A microwave multidimensional parameter measurement system based on differential frequency-time mapping includes: a pulsed light source, an input dispersive medium, a first Mach-Zehnder modulator (MZM), a second Mach-Zehnder modulator (MZM), an RF power divider, an adjustable optical delay line, an optical coupler, an output dispersive medium, a photodetector, an analog-to-digital converter (ADC), and a digital signal processor. The pulsed light source outputs an optical pulse that enters the input dispersive medium for pulse broadening, and then enters a Sagnac loop (also commonly referred to as a Sagnac loop). Simultaneously, the microwave signal under test is split by the RF power divider and input to the two Mach-Zehnder modulators within the Sagnac loop to modulate the optical pulse. An adjustable optical delay line is positioned between the first Mach-Zehnder modulator and the optical coupler. The modulated optical pulse output from the Sagnac loop passes through the output dispersive medium, and frequency-time mapping is achieved based on a real-time Fourier transform mechanism using time convolution, mapping the spectral information to the time domain. After the optical signal is converted into an electrical signal by a photodetector, the time-domain waveform of the output signal of the photodetector is acquired; the electrical signal is converted into a digital signal by an analog-to-digital converter and input to a digital signal processor for processing to obtain the time, frequency, amplitude and phase information of the microwave signal under test.

[0008] As a preferred embodiment, the input dispersion medium and the output dispersion medium are selected from one or more combinations of chirped fiber gratings or optical fibers.

[0009] As a preferred option, the dispersion value of the input dispersion medium is equal to that of the output dispersion medium but opposite in sign, so as to form a dispersion complementary structure.

[0010] As a preferred embodiment, the adjustable optical delay line is used to adjust the relative time delay of the bidirectional propagating light within the Sagnac ring, so that the clockwise and counterclockwise optical pulses are staggered in the time domain, respectively carrying different time segments of the same microwave signal, and achieving coherent superposition and interference at the output of the optical coupler.

[0011] As a preferred option, the delay introduced by the tunable delay line should be greater than the time of frequency-time mapping of a single microwave signal.

[0012] As a preferred embodiment, the period of the input optical pulse corresponds to the period of the frequency-time mapping of the microwave signal, and each frequency of the microwave signal corresponds to the generation of two electrical pulses within a mapping period.

[0013] As a preferred option, when the microwave signal is a continuous wave signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line remains constant, and the corresponding output signal amplitude will also remain constant; when the microwave signal is a linear frequency modulated chirped signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line exhibits periodic changes, and the corresponding output signal amplitude will also change with the time period; when the microwave signal is a BPSK (binary phase shift keying) signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line will have jumps, and the corresponding output signal amplitude will also have jumps.

[0014] Another objective of this invention is to provide a method for implementing a microwave multidimensional parameter measurement system based on differential frequency-time mapping, the steps of which are as follows:

[0015] S1, pulsed light source The periodic output half-width is A pulse train, the pulse train passes through a dispersion of The light pulse is broadened after dispersion at the input end, and then input into the Sagnac ring.

[0016] S2. The microwave signal to be measured is simultaneously input to two Mach-Zehnder modulators after passing through an RF power divider. The clockwise optical pulse is introduced by an adjustable optical delay line. The delay causes the clockwise and counterclockwise optical pulses to be modulated at different times in the time domain, respectively carrying different time segments of the same microwave signal, and achieving coherent superposition and interference at the output of the optical coupler.

[0017] S3. Set both the first and second Mach-Zehnder modulators to operate at the minimum bias point.

[0018] The beat frequency signals output from S4 and Sagnac rings undergo dispersion of... The output dispersive medium completes the frequency-to-time mapping of the microwave signal, and then the signal waveform is acquired by a photodetector and an analog-to-digital converter.

[0019] S5, Digital Signal Processor Analysis of a Single Cycle The time interval between two electrical pulses The frequency of the microwave signal under test is obtained by time interval analysis. Simultaneously analyze the signal envelope expression. The time, amplitude, and phase information of the microwave signal under test can be obtained by analyzing this relationship.

[0020] Compared with the prior art, the beneficial effects of this invention are:

[0021] (1) This invention places the core delay and interference synthesis in the optical domain, which fundamentally avoids the problems of narrow bandwidth, high loss and poor adjustability of electronic delay lines.

[0022] (2) Based on the large bandwidth and real-time characteristics of the optical real-time Fourier transform processing architecture, this invention can simultaneously perform high-precision measurement of the time, frequency, amplitude and phase of multi-carrier microwave signals. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the microwave multidimensional parameter measurement system of the present invention;

[0024] Figure 2 This is a schematic diagram illustrating the principle of the BPSK signal modulation format recognition process according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the response characteristics of an embodiment of the present invention;

[0026] Figure 4 Figure 1 shows the experimental results of multi-dimensional parameter detection of BPSK signal encoded by Hamming code according to an embodiment of the present invention. Figure 2 shows the complete waveform and the local magnified time-domain waveform at the transition point. Figure 3 shows the collected output results.

[0027] Figure 5 The figures show the experimental results, where (a) is the mapping result for one time window and (b) is the phase coding result of the BPSK signal.

[0028] Among them: 1. Pulsed light source, 2. Input dispersive medium, 3a. First Mach-Zehnder modulator, 3b. Second Mach-Zehnder modulator, 4. Radio frequency power divider, 5. Adjustable optical delay line, 6. Optical coupler, 7. Output dispersive medium, 8. Photodetector, 9. Analog-to-digital converter, 10. Digital signal processor. Detailed Implementation

[0029] To more clearly illustrate the embodiments of the present invention, specific implementation methods will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0030] Example:

[0031] like Figure 1As shown, this embodiment proposes a microwave multidimensional parameter measurement system and method based on differential frequency-time mapping. It employs real-time Fourier transform technology based on Sagnac rings and time convolution to achieve simultaneous measurement of the time, frequency, and amplitude of multi-carrier signals. The system includes: a pulsed light source 1, an input dispersive medium 2, a first Mach-Zehnder modulator 3a, a second Mach-Zehnder modulator 3b, an RF power divider 4, a tunable optical delay line 5, an optical coupler 6, an output dispersive medium 7, a photodetector 8, an analog-to-digital converter 9, and a digital signal processor 10. Specifically, the input dispersive medium 2 is a single-mode optical fiber, and the output dispersive medium 7 is a dispersion-compensating optical fiber. The specific implementation method of a microwave multidimensional parameter measurement system and method based on differential frequency-time mapping includes the following steps:

[0032] The pulsed light source 1 outputs a light pulse that enters the input dispersion medium 2 to complete pulse broadening, and then enters the Sagnac ring. Simultaneously, the microwave signal under test is split by the RF power divider 4 and input into two Mach-Zehnder modulators 3a and 3b within the Sagnac ring to modulate the light pulse. An adjustable optical delay line 5 is provided between the first Mach-Zehnder modulator 3a and the optical coupler 6. The modulated light pulse output from the Sagnac ring passes through the output dispersion medium 7, and frequency-time mapping is achieved based on the real-time Fourier transform mechanism of time convolution, mapping the spectral information to the time domain. After the optical signal is converted into an electrical signal by the photodetector 8, the time-domain waveform of the signal output by the photodetector 8 is acquired. The electrical signal is converted into a digital signal by the analog-to-digital converter 9 and input to the digital signal processor 10 for processing to obtain the time, frequency, amplitude, and phase information of the microwave signal under test.

[0033] The input dispersion medium 2 and the output dispersion medium 7 are selected from one or more combinations of chirped fiber gratings or optical fibers. The dispersion value of the input dispersion medium 2 is equal to that of the output dispersion medium 7 but opposite in sign, so as to form a dispersion complementary structure.

[0034] The adjustable optical delay line 5 is used to adjust the relative time delay of the bidirectional propagating light within the Sagnac ring, so that the clockwise and counterclockwise optical pulses are staggered in the time domain, carrying different time segments of the same microwave signal respectively, and achieving coherent superposition and interference at the output of the optical coupler. Introducing an adjustable optical delay line into the Sagnac ring enables key delay processing in the optical domain. Compared to delaying in the electrical domain, this effectively avoids distortion and loss of high-frequency microwave signals during transmission, significantly improving the frequency range and accuracy of multi-dimensional parameter measurements of microwave signals.

[0035] Delay introduced by tunable delay line 5 It should be greater than the time of frequency mapping of a single microwave signal. This ensures that the pulse amplitude after differential frequency mapping can accurately reflect the phase change of the microwave signal.

[0036] The period of the input optical pulse corresponds to the period of the frequency-time mapping of the microwave signal, and each frequency of the microwave signal corresponds to generating two electrical pulses within one mapping period. When the microwave signal is a continuous wave signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line 5 remains constant, and the corresponding output signal amplitude will also remain constant. When the microwave signal is a linear frequency modulated chirped signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line 5 exhibits periodic changes, and the corresponding output signal amplitude will also change with the time period. When the microwave signal is a BPSK signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line 5 will have jumps, and the corresponding output signal amplitude will also have jumps.

[0037] Another objective of this invention is to provide a method for implementing a microwave multidimensional parameter measurement system based on differential frequency-time mapping, the steps of which are as follows:

[0038] S1, pulsed light source The periodic output half-width is A pulse train, the pulse train passes through a dispersion of The light pulse is broadened after dispersion at the input end, and then input into the Sagnac ring.

[0039] S2. The microwave signal to be measured is simultaneously input to two Mach-Zehnder modulators after passing through an RF power divider. The clockwise optical pulse is introduced by an adjustable optical delay line. The delay causes the clockwise and counterclockwise optical pulses to be out of time in the modulation time domain, so that they can carry different time segments of the same microwave signal respectively, and achieve coherent superposition and interference at the output of the optical coupler.

[0040] S3. Set both the first and second Mach-Zehnder modulators to operate at the minimum bias point.

[0041] The beat frequency signals output from S4 and Sagnac rings undergo dispersion of... The output dispersive medium completes the frequency-to-time mapping of the microwave signal, and then the signal waveform is acquired by a photodetector and an analog-to-digital converter.

[0042] S5, Digital Signal Processor Analysis of a Single Cycle The time interval between two electrical pulses The frequency of the microwave signal under test is obtained by time interval analysis. Simultaneously analyze the signal envelope expression. The time, amplitude, and phase information of the microwave signal under test can be obtained by analyzing this relationship.

[0043] The working principle of the microwave multidimensional parameter measurement system and method based on differential frequency-time mapping provided by this invention is as follows:

[0044] Theoretically, the light pulse train output by a pulsed light source can be represented as:

[0045] (1)

[0046] In the formula It is the period of the optical pulse train, which represents the system's interval. A frequency-time mapping is performed, where t represents time and i represents the i-th light pulse. It is the full width at half maximum (FWHM) of the pulse, and A is the amplitude of the light pulse. The light pulse train passes through a dispersion value of The input dispersion completes pulse broadening. The expression for the broadened pulse is:

[0047] (2)

[0048] The microwave signal to be measured is input into the first Mach-Zehnder modulator and the second Mach-Zehnder modulator, respectively. The clockwise light pulse passes through... The delay, while the counterclockwise light pulse directly enters the second Mach-Zehnder modulator.

[0049] The microwave signal to be measured entering the Mach-Zehnder modulator can be expressed as:

[0050] (3)

[0051] in It is the angular frequency of the microwave signal to be measured. It is the frequency of the microwave signal to be measured. It is the amplitude of the microwave signal to be measured. It is the normalized envelope of the microwave signal under test. Phase information of the signal. After carrier-suppressed double-sideband modulation, the clockwise and counterclockwise signals are denoted as follows: , , can be represented as:

[0052] (4)

[0053] This is the half-wave voltage of the Mach-Zehnder modulator, and the extinction ratio of the Mach-Zehnder modulator is assumed to be infinite during the derivation. Expanding (4) using Bessel and ignoring higher-order terms, the two signal expressions can be rewritten as:

[0054] (5)

[0055] in, It is the modulation coefficient. It is a first-order Bessel function of the first kind. The Sagnac loop outputs clockwise and counterclockwise signals, which can be expressed as:

[0056] (6)

[0057] The coherent signal passes through the dispersive medium at the output terminal, achieving frequency-time mapping. The expression for this signal can then be written as:

[0058] (7)

[0059] The light pulse then undergoes photoelectric conversion via a photodetector, and the electrical signal envelope at this point can be written as:

[0060] (8)

[0061] As shown in (8), there are two pulses within each mapping window. The time interval between the pulses is... The frequency is related to the frequency of the microwave signal being measured, and can be calculated using the following formula:

[0062] (9)

[0063] Furthermore, for the parameters of the microwave signal under test, such as pulse amplitude, pulse width, and pulse period, it is known in the case of small-signal modulation that... The maximum value of the signal envelope at this point can be written as:

[0064] (10)

[0065] R is the matching resistor. Combining the modulation coefficient expression mentioned above, the pulse envelope expression of the microwave signal under test can be obtained as follows:

[0066] (11)

[0067] The pulse amplitude, pulse width, pulse period, and other information of the pulse signal are all contained within it. The identification of intra-pulse modulation formats can be achieved by analyzing the amplitude changes of the waveform after frequency-time mapping. Taking the BPSK signal as an example, It takes the value 0 or π. When Where k is any integer, when the BPSK signal experiences a phase transition, in time... Inside There will also be a jump, The value can be either the maximum or minimum value. The amplitude transition position is the BPSK symbol change position. Therefore, this scheme can not only identify the intra-pulse BPSK signal format, but also analyze the encoding.

[0068] In this embodiment, its overall structure is as follows: Figure 1 As shown in the figure. In the system, the optical pulse train has a period of 20 ns and a full width at half maximum (FWHM) of 8 ps. To satisfy the temporal convolution condition, the dispersion values ​​of the dispersive medium at the input and output ends are set to ±10 ns / nm, with opposite signs. The working principle of the system to realize BPSK signal modulation format recognition is as follows. Figure 2 As shown, the delay module introduces a time delay of 200 ns. Since the system's mapping period is 20 ns, this approximately 200 ns delay will cause amplitude jumps in at least 10 mapping windows.

[0069] The system's response characteristics to input signals are as follows: Figure 3 As shown. Figure 3 The phase difference-amplitude response characteristics shown in the figure are the basis for realizing phase demodulation of BPSK signals. Figure 3 The input voltage-amplitude response characteristics of the system are shown in the figure. When the input voltage is less than 2.052 V, the response curve is monotonically increasing, thus ensuring that unambiguous amplitude measurement can be achieved in this range.

[0070] Experimental results of multidimensional parameter detection of BPSK signals are as follows: Figure 4 and Figure 5 As shown. The microwave signal under test is a BPSK signal with a center frequency of 10 GHz, a pulse period of 10 μs, and a pulse width of 7 μs. The code group is set to a 7-bit Hamming code 1000101 with a symbol period of 1 μs. Its complete waveform and the locally magnified time-domain waveform at the transition point are shown in the figure. Figure 4 As shown in Figure (a), the photoelectric conversion is completed by the photodetector, and the electrical pulse information is collected by the analog-to-digital converter. The collected output result is as follows. Figure 4 As shown in Figure (b), the amplitude values ​​at both ports maintain a polarized relationship, accompanied by amplitude jumps, and the amplitude jump positions correspond to the symbol change positions. Figure 5 As shown in Figure (a), observing the mapping results of one time window, the actual frequency measurement result is 12.45 GHz, which is consistent with the theoretical derivation. Based on... Figure 4 The results in Figure (b) show the phase encoding of the BPSK signal, as follows: Figure 5 As shown in Figure (b), the above process demonstrates the system's ability to simultaneously measure the time, frequency, phase change, and amplitude of microwave signals.

[0071] For other structures and principles, please refer to Example 1.

[0072] It should be noted that the above embodiments can be freely combined as needed. The above description is only a detailed explanation of the preferred embodiments and principles of the present invention. For those skilled in the art, there will be changes in the specific implementation methods based on the ideas provided by the present invention, and these changes should also be considered within the scope of protection of the present invention.

Claims

1. A microwave multidimensional parameter measurement system based on differential frequency-time mapping, characterized in that, It includes a pulsed light source, an input dispersive medium, a first Mach-Zehnder modulator, a second Mach-Zehnder modulator, an RF power divider, a tunable optical delay line, an optical coupler, an output dispersive medium, a photodetector, an analog-to-digital converter, and a digital signal processor. The pulsed light source outputs a light pulse that enters the input dispersion medium to complete pulse broadening, and then enters the Sagnac ring. Simultaneously, the microwave signal under test is split by an RF power divider and input into two Mach-Zehnder modulators within the Sagnac ring to modulate the light pulse. An adjustable optical delay line is provided between the first Mach-Zehnder modulator and the optical coupler. The modulated light pulse output from the Sagnac ring passes through the output dispersion medium, and frequency-time mapping is achieved based on a real-time Fourier transform mechanism using time convolution, mapping the spectral information to the time domain. After the optical signal is converted into an electrical signal by a photodetector, the time-domain waveform of the photodetector output signal is acquired. The electrical signal is converted into a digital signal by an analog-to-digital converter and input to a digital signal processor for processing to obtain the time, frequency, amplitude, and phase information of the microwave signal under test.

2. The microwave multidimensional parameter measurement system based on differential frequency-time mapping according to claim 1, characterized in that, The input dispersion medium and the output dispersion medium are selected from one or more combinations of chirped fiber gratings or optical fibers.

3. The microwave multidimensional parameter measurement system based on differential frequency-time mapping according to claim 1, characterized in that, The dispersion value of the input dispersion medium is equal to that of the output dispersion medium but opposite in sign, thus forming a dispersion complementary structure.

4. The microwave multidimensional parameter measurement system based on differential frequency-time mapping according to claim 1, characterized in that, The adjustable optical delay line is used to adjust the relative time delay of the bidirectional propagating light within the Sagnac ring, so that the clockwise and counterclockwise optical pulses are staggered in the time domain, carrying different time segments of the same microwave signal respectively, and achieving coherent superposition and interference at the output of the optical coupler.

5. The microwave multidimensional parameter measurement system based on differential frequency-time mapping according to claim 1, characterized in that, The delay introduced by the tunable optical delay line is greater than the time of frequency-time mapping of a single microwave signal.

6. The microwave multidimensional parameter measurement system based on differential frequency-time mapping according to claim 1, characterized in that, The period of the optical pulse corresponds to the period of the frequency-time mapping of the microwave signal, and each frequency of the microwave signal corresponds to the generation of two electrical pulses within a mapping period.

7. The microwave multidimensional parameter measurement system based on differential frequency-time mapping according to claim 1, characterized in that, When the microwave signal is a continuous wave signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line remains constant, and the corresponding output signal amplitude will also remain constant. When the microwave signal is a linear frequency modulated chirped signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line exhibits periodic changes, and the corresponding output signal amplitude will also change with the time period. When the microwave signal is a BPSK signal, the phase difference between the microwave signal and the delay signal introduced by the tunable optical delay line jumps, and the corresponding output signal amplitude also jumps.

8. A microwave multidimensional parameter measurement method based on differential frequency-time mapping, used to implement the microwave multidimensional parameter measurement system according to any one of claims 1 to 7, characterized in that, The steps are as follows: S1, pulsed light source The periodic output half-width is A pulse train, the pulse train passes through a dispersion of The light pulse is broadened after dispersion at the input end, and then input into the Sagnac ring; S2. The microwave signal to be tested is simultaneously input to two Mach-Zehnder modulators after passing through an RF power divider. The clockwise optical pulse is introduced by an adjustable optical delay line. The time delay causes the clockwise and counterclockwise optical pulses to be modulated at different times in the time domain, respectively carrying different time segments of the same microwave signal, and achieving coherent superposition and interference at the output of the optical coupler; S3. Set both the first and second Mach-Zehnder modulators to operate at the minimum bias point. The beat frequency signals output from S4 and Sagnac rings undergo dispersion of... The output dispersive medium completes the frequency-to-time mapping of the microwave signal, and then the signal waveform is acquired by a photodetector and an analog-to-digital converter. S5, Digital Signal Processor Analysis of a Single Cycle The time interval between two electrical pulses The frequency of the microwave signal under test is obtained by time interval analysis. Simultaneously, the signal envelope expression is analyzed, and the time, amplitude, and phase information of the microwave signal under test are obtained through this relationship.

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