Microwave multi-information measuring device and method based on multi-local-oscillator microwaves

Abstract

The invention belongs to the technical field of microwave information measurement, and discloses a microwave multi-information measurement device based on multi-local oscillator microwaves, which comprises a detection laser module, a coupling laser module, a signal detection module, a local oscillator signal generation module and a signal processing module, the detection laser module is used for outputting first detection light, second detection light, first reference light and second reference light to the detection unit; the coupling laser module is used for outputting coupling light to the detection unit; the local oscillation signal generation module is used for outputting a plurality of local oscillation microwave signals with the same phase and a propagation path perpendicular to a light beam path in the detection unit to the detection unit; the first detection light and the first reference light are received by the first balance detector, the second detection light and the second reference light are received by the second balance detector, and microwave information to be detected is obtained through calculation of the signal processing module.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microwave information measurement, and in particular to a microwave multi-information measurement device and method based on multiple local oscillation microwaves. BACKGROUND

[0002] Although the traditional classical microwave measurement technology is mature, the measurement instruments based on classical microwave circuits and devices such as waveguides and coaxial cables have certain reliability in the measurement of parameters such as frequency, power and phase of conventional microwave signals, but their equipment is usually bulky and complex in structure, which is difficult to meet the needs of portability and integration. In addition, the traditional measurement process has the following shortcomings: first, the calibration operation is complex; second, the detection range is small; third, the measurement accuracy is affected by electromagnetic interference. More importantly, the traditional method cannot simultaneously collect multi-element information of microwaves.

[0003] In contrast, the microwave quantum sensor based on Rydberg atoms has the following advantages: first, no calibration is required; second, high sensitivity can detect extremely weak microwave signals, and has ultra-narrow linewidth, which can realize high-precision frequency resolution; third, it is not easy to be disturbed by noise. However, the existing microwave information measurement system mostly measures single parameters, such as the frequency, electric field strength or phase of the microwave, and cannot realize the multi-information measurement of the microwave. If the complete information of the microwave signal is to be obtained, it is often necessary to use multiple different measurement devices to measure respectively, which not only increases the complexity and cost of measurement, but also may lead to inaccurate measurement results between different devices, thereby affecting the accurate analysis and understanding of the overall characteristics of the microwave signal. Therefore, a device capable of simultaneously measuring multi-information of microwaves needs to be designed to overcome the limitations of the prior art. SUMMARY

[0004] In order to solve the above technical problems, the present application proposes a microwave multi-information measurement device and method based on multiple local oscillation microwaves, which uses multiple directionally orthogonal and independently local oscillation microwaves to cooperatively detect the intensity, frequency, phase and polarization of microwaves, so as to realize the multi-information measurement of microwaves.

[0005] In order to solve the above technical problems, the technical scheme adopted by the present application is as follows: a microwave multi-information measurement device based on multiple local oscillation microwaves, comprising: a probe laser module, a coupling laser module, a signal detection module, a local signal generation module and a signal processing module; The signal detection module comprises a detection unit, a polarization beam splitter, a first balanced detector and a second balanced detector. The detection laser module is configured to output first detection light, second detection light, first reference light and second reference light to the detection unit; the first detection light is frequency-shifted, orthogonally polarized and light-path coincided with the second detection light, the first reference light has the same frequency and polarization as the first detection light, and the second reference light has the same frequency and polarization as the second detection light; the coupling laser module is configured to output a coupling light which is directionally coincided with the first detection light and the second detection light to the detection unit, and the coupling light is used to meet the first detection light and the second detection light in the detection unit to generate the EIT effect; The local oscillator signal generation module is configured to output a plurality of local oscillator microwave signals which have the same phase and are perpendicular to the light beam path in the detection unit in the propagation path to the detection unit; The first detection light, the second detection light, the first reference light and the second reference light are separated by a polarization beam splitter after passing through the detection unit, wherein the first detection light and the first reference light are received by the first balanced detector, and the second detection light and the second reference light are received by the second balanced detector; The output signals of the first balanced detector and the second balanced detector are calculated by the signal processing module to obtain the to-be-measured microwave information.

[0006] The to-be-measured microwave information calculated by the signal processing module includes the electric field intensity, frequency, phase information and polarization angle of the to-be-measured microwave.

[0007] The detection laser module includes a detection laser and a beam splitting module, the beam splitting module includes a half-wave plate, a first polarization beam splitter, an acousto-optic modulator, a first light splitting device, a second light splitting device and a second polarization beam splitter; the laser output by the detection laser is split into two beams after passing through the half-wave plate and the first polarization beam splitter, one of which is a vertically polarized light, and the other of which is a horizontally polarized light; the vertically polarized light is frequency-shifted by the acousto-optic modulator and then split into the first detection light and the first reference light by the first light splitting device; the horizontally polarized light is reflected by the first mirror and then split into the second detection light and the second reference light by the second light splitting device; the horizontally polarized second detection light J is reflected by the fourth mirror and then coincides with the vertically polarized first detection light after the second polarization beam splitter, and then enters the detection unit; the first reference light and the second reference light are reflected by the second mirror and the third mirror respectively, and then enter the detection unit in parallel with the detection light.

[0008] The shift amount of the acousto-optic modulator is 180-200 MHz.

[0009] The local oscillator signal generation module comprises a local oscillator signal generation device, a power divider, a phase compensator and a transmitter, the local oscillator signal generation device transmits a plurality of local oscillator microwave groups to the power divider and the phase compensator, and then to different transmitters, and the phase compensator is used for compensating the initial phase of each microwave in each local oscillator microwave group so as to keep the initial phase consistent, and each transmitter is used for transmitting one of the local oscillator microwave groups, and each local oscillator microwave group comprises two polarized orthogonal microwaves.

[0010] The signal processing module comprises a phase-locked amplifier, a spectrum analyzer, an oscilloscope and a calculation unit; the phase-locked amplifier is used for extracting the phase information carried by the beat frequency signals output by the first balanced detector and the second balanced detector; the spectrum analyzer is used for performing spectrum analysis on the detection laser passing through the detection unit to obtain spectrum information; the oscilloscope is used for directly observing and storing the beat frequency signals; and the calculation unit is used for obtaining the to-be-measured microwave information according to the beat frequency signals, the phase information and the spectrum information.

[0011] The detection unit is an alkali metal atom vapor cell.

[0012] In addition, the application further provides a microwave multi-information measurement method based on multiple local oscillator microwaves, which is realized according to the microwave multi-information measurement device based on multiple local oscillator microwaves and comprises the following steps. Step one: to-be-measured microwave intensity measurement; comprising: A group of orthogonal polarized local oscillator microwaves are applied, and the first balanced detector and the second balanced detector receive signals, and the beat frequency signals in the two groups of received signals are subjected to spectrum analysis to obtain the electric field intensity E1 of the to-be-measured microwave; Another group of orthogonal polarized local oscillator microwaves are applied, and the beat frequency signals of the first balanced detector and the second balanced detector are subjected to spectrum analysis to obtain the electric field intensity E2 of the to-be-measured microwave; The electric field intensity E1 and the electric field intensity E2 are combined to obtain the electric field intensity of the to-be-measured microwave; Step two: to-be-measured microwave frequency measurement; comprising: A group of orthogonal polarized local oscillator microwaves are applied, and the first balanced detector and the second balanced detector receive signals, and the beat frequency signals in the two groups of received signals are subjected to spectrum analysis, the frequency of the local oscillator microwave is changed, and the frequency f1 of the to-be-measured microwave is determined according to the strongest beat frequency signal obtained; Another group of orthogonal polarized local oscillator microwaves are applied, and the first balanced detector and the second balanced detector receive signals, and the beat frequency signals in the two groups of received signals are subjected to spectrum analysis, the frequency of the local oscillator microwave is changed, and the frequency f2 of the to-be-measured microwave is obtained according to the strongest beat frequency signal obtained; The frequency f1 and the frequency f2 are combined to determine the frequency of the to-be-measured microwave; Step three: carry out the measured microwave phase measurement, comprising: A set of applied orthogonal polarization of the local microwave, through the first balanced detector and the second balanced detector receive signal, the received two groups of signal beat frequency signal for phase sensitive detection, get two beat frequency signal phase information; Another set of applied orthogonal polarization of the local microwave, through the first balanced detector and the second balanced detector receive signal, the received two groups of signal beat frequency signal for phase sensitive detection, get two beat frequency signal phase information; Combined with the phase information twice, determine the phase of the measured microwave; Step four: carry out the measured microwave polarization measurement, comprising: A set of applied orthogonal polarization of the local microwave A, B and another set of applied orthogonal polarization of the local microwave C, D, through the first balanced detector and the second balanced detector receive signal, the received two groups of signal beat frequency signal amplitude analysis, get two horizontal polarization ; A set of applied orthogonal polarization of the local microwave A, B and another set of applied orthogonal polarization of the local microwave C, D, through the first balanced detector and the second balanced detector receive signal, the received two groups of signal beat frequency signal amplitude analysis, get two vertical polarization ; Combined with the horizontal polarization and vertical polarization information twice, calculate the polarization angle of the measured microwave, the formula is: ; Among them, The phase difference between the horizontal polarization And vertical polarization Of the detection unit.

[0013] Compared with the prior art, the present application has the following beneficial effects: The application provides a microwave multi-information measuring device and method based on multiple local oscillator microwaves, which realizes synchronous high-precision measurement of multiple information of a to-be-measured microwave, such as electric field intensity, frequency, phase and polarization, by using multiple local oscillator microwaves in different directions, which are orthogonal and independent, and cooperating with Rydberg atom heterodyne detection technology. Multiple local oscillator channels are integrated by using a dual-polarized radio frequency horn, and a dual-optical-path laser excitation system is combined, so that there is a frequency offset between a first probe light and a second probe light, two groups of independent stepped energy levels are formed, and the polarizations are different, which can reduce the influence of polarization matching of light and microwave on EIT-AT spectrum, and improve the microwave measurement precision. In addition, the spatial positions coincide, which greatly reduces the space occupation of optical and radio frequency components. The multiple local oscillator microwave frequencies are separated from the to-be-measured signal projection through a small frequency difference, the beat frequency signals between the microwaves are used to directly extract the amplitude and phase difference of each direction electric field component, and high-sensitivity measurement is completed. Therefore, the application has the advantages of small size, convenient carrying, simple operation, high measurement precision, and multiple information of the to-be-measured microwave, such as electric field intensity, phase, frequency and polarization, can be obtained in sequence. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 A structure schematic view of a microwave multi-information measuring device based on multiple local oscillator microwaves is provided for the first embodiment of the application. Figure 2 A light path structure schematic view of a detection laser module and a signal detection module is provided for the first embodiment of the application. Figure 3 A local schematic view of a detection module is provided for the first embodiment of the application. Figure 4 A structure schematic view of a local oscillator signal generation module is provided for the first embodiment of the application. Figure 5 A flow chart of a microwave information measuring method based on multiple local oscillator microwaves is provided for the second embodiment of the application.

[0015] In the figure, 1 is a detection laser, 2 is a beam splitting module, 3 is a first beam shaper, 4 is a first frequency locking system, 5 is a coupling laser, 6 is a second frequency locking system, 7 is a second beam shaper, 8 is a local oscillator signal generation device, 9 is a resistive power divider, 10 is a phase compensator, 11 is a to-be-measured signal generation device, 12 is a detection unit, 13 is a polarization beam splitter, 14 is a first balanced detector, 15 is a second balanced detector, 16 is a phase-locked amplifier, 17 is a spectrum analyzer, 18 is an oscilloscope, 19 is a calculation unit, and 20 is a display. 2-1-Half-wave plate; 2-2-First polarizing beam splitter; 2-3-Acousto-optic modulator; 2-4-First beam splitter; 2-5-Second polarizing beam splitter; 2-6-First dichroic mirror; 2-7-Second reflecting mirror; 2-8-First reflecting mirror; 2-9-Second beam splitter; 2-10-Third reflecting mirror; 2-11-Fourth reflecting mirror; 2-12-Second dichroic mirror; 13-Polarizing beam splitter; 2-13-Fifth reflecting mirror. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1 like Figure 1 As shown, Embodiment 1 of the present invention provides a microwave multi-information measurement device based on multi-local oscillator microwaves, including: a detection laser module, a coupling laser module, a signal detection module, a local oscillator signal generation module, and a signal processing module.

[0018] Specifically, the signal detection module includes a detection unit, a polarization beam splitter, a first balanced detector, and a second balanced detector. The detection unit is specifically an alkali metal atom vapor cell.

[0019] Specifically, in this embodiment, the detection laser module is used to output a first detection light, a second detection light, a first reference light, and a second reference light that are parallel to each other to the detection unit; wherein the first detection light is frequency-shifted and orthogonally polarized relative to the second detection light, the first reference light has the same frequency and polarization as the first detection light, and the second reference light has the same frequency and polarization as the second detection light; the coupling laser module is used to output two coupled beams that are opposite in direction to the first and second detection lights to the detection unit, and the coupled beams and the corresponding detection lights meet at the detection unit to produce the EIT effect.

[0020] The local oscillator signal generation module is used to output multiple local oscillator microwave signals with the same phase and propagation path perpendicular to the beam path in the detection unit to the detection unit; the first detection beam, the second detection beam, the first reference beam, and the second reference beam are separated by the polarization beam splitter 13 after passing through the detection unit, wherein the first detection beam and the first reference beam enter the first balanced detector, and the second detection beam and the second reference beam enter the second balanced detector; the output signals of the first balanced detector and the second balanced detector are calculated by the signal processing module to obtain the microwave information to be measured.

[0021] Specifically, in this embodiment, the microwave information to be tested calculated by the signal processing module includes the electric field strength, frequency, phase information, and polarization angle of the microwave to be tested.

[0022] like Figure 1 As shown, in this embodiment, the detection laser module includes a detection laser 1 and a beam splitter module 2, as follows: Figure 2 As shown, the beam splitting module includes a half-wave plate 2-1, a first polarizing beam splitter 2-2, an acousto-optic modulator 2-3, a first beam splitter 2-4, a second beam splitter 2-9, and a second polarizing beam splitter 2-5. The laser output from the probe laser 1 is split into two beams after passing through the half-wave plate 2-1 and the first polarizing beam splitter 2-2. One beam is vertically polarized light, which is frequency-shifted by the acousto-optic modulator 2-3 and then split into a first probe beam I and a first reference beam RefI by the first beam splitter 2-4. The other beam is horizontally polarized light, which is reflected by the first reflector 2-8 and then split into a second probe beam J and a second reference beam RefJ by the second beam splitter 2-9. The horizontally polarized second probe beam J is reflected by the fourth reflector 2-11 and then combined with the vertically polarized first probe beam I by the second polarizing beam splitter 2-5 before entering the probe unit 12. The first reference light RefI and the second reference light RefJ are reflected by the second reflector 2-7 and the third reflector 2-10, respectively, and then incident parallel to the probe light onto the detector unit 12. A polarization beam splitter 13 is positioned on the optical path of the probe light. After passing through the polarization beam splitter 13, the first probe light I is transmitted and enters the first balanced detector 14 together with the first reference light RefI. The second probe light J is reflected and enters the second balanced detector 15 together with the second reference light RefJ, which has been reflected by the fifth reflector 2-11.

[0023] Specifically, in this embodiment, the offset of the acousto-optic modulator is set to 180-200 MHz. Therefore, the frequency offset of the first probe light I and the second probe light J is 180-200 MHz.

[0024] In addition, in this embodiment, the signal detection module also includes a first dichroic mirror 2-6 and a second dichroic mirror 2-12 disposed on both sides of the detection unit 12. The first dichroic mirror 2-6 and the second dichroic mirror 2-12 are located on the optical path of the detection light. The pump light is reflected by the second dichroic mirror 2-12 and coincides with the detection light in the opposite direction before entering the detection unit 12. Then, it is reflected by the first dichroic mirror 2-6 and leaves the optical path where the detection light is located.

[0025] Furthermore, in this embodiment, the detection laser module also includes a first frequency locking system 4 and a first beam shaper 3, wherein the first frequency locking system 4 is used to lock the light output by the detection laser 1, and the first beam shaper 3 is used for shaping.

[0026] Furthermore, in this embodiment, the coupled laser module includes a coupled laser 5, a second frequency locking system 6, and a second beam shaper 7. The second frequency locking system 6 is used to lock the light output by the coupled laser 5, and the second beam shaper 7 is used for shaping.

[0027] like Figure 3 As shown, in this embodiment, the local oscillator signal generation module is used to output four local oscillator microwave signals with the same phase and propagation paths perpendicular to the beam path in the detection unit to the detection unit. Local oscillator microwaves A and B propagate along the z-axis, while local oscillator microwaves C and D propagate along the x-axis. The polarization directions of local oscillator microwaves A and B are perpendicular, along the x-axis and y-axis respectively; the polarization directions of local oscillator microwaves C and D are perpendicular, along the z-axis and y-axis respectively.

[0028] In this embodiment, the frequencies of the four local oscillator microwaves are relative to the rubidium atom energy levels. to energy level The transition frequencies between these frequencies, at 10.663 GHz, shift to A = 10.6633 GHz, B = 10.66327 GHz, C = 10.6628 GHz, and D = 10.66278 GHz, with shift amounts of [missing information]. kHz kHz kHZ, kHz, to avoid beat frequency overlap.

[0029] Furthermore, such as Figure 4 As shown, in this embodiment, the local oscillator signal generation module includes a local oscillator signal generator, a power divider, a phase compensator, and a transmitter. Multiple local oscillator microwave groups emitted by the local oscillator signal generator are transmitted to different transmitters via the power divider and the phase compensator, and then transmitted to the detection unit via the transmitters. The phase compensator is used to compensate for the initial phase of each microwave in each local oscillator microwave group to keep them consistent. Each transmitter is used to transmit one local oscillator microwave group, and each local oscillator microwave group includes two microwaves with orthogonal polarization.

[0030] Furthermore, such as Figure 1 As shown, in this embodiment, the signal processing module includes a lock-in amplifier, a spectrum analyzer, an oscilloscope, and a computing unit. The lock-in amplifier is used to extract the phase information carried by the beat frequency signals output by the first balanced detector and the second balanced detector. The spectrum analyzer is used to perform spectrum analysis on the probe laser passing through the detection unit to obtain spectrum information. The oscilloscope is used to directly observe and store the beat frequency signal. The computing unit is used to obtain the microwave information to be measured based on the beat frequency signal, phase information, and spectrum information.

[0031] Specifically, the first and second balance detectors can be the balance detectors of Thorlabs, model PDB415A.

[0032] Specifically, in this embodiment, the probe laser 1 generates a 780 nm probe laser, and the coupling laser 5 generates a 480 nm coupling laser. The frequency of the probe laser is locked, and the frequency of the coupling laser is scanned, allowing the probe laser and coupling laser to interact with atoms within the probe unit. For example... Figure 3 As shown, the first probe light I and the second probe light J have orthogonal polarization directions and coincident spatial positions. The first reference light RefI and the second reference light RefJ are incident on the detection unit 12 in parallel with the first probe light I and the second probe light J. The coupling laser enters from the other end of the detection unit and coincides with the first probe light I and the second probe light J in the opposite direction. The two probe lights excite the ground-state atoms of the detection unit 12 to the excited state, and the coupling light excites the excited-state atoms to the Rydberg state. The signal detected by the balanced detector is observed through an oscilloscope to show the electromagnetically induced transparency (EIT) phenomenon of the Rydberg atoms.

[0033] Furthermore, in this embodiment, the computing unit can provide feedback based on the measurement information and control various parameters of the detection and coupling laser, as well as parameters such as the frequency and phase of the local oscillator microwave electric field, through servo control, thereby continuously optimizing the measurement signal and ultimately obtaining more accurate measurement results.

[0034] Specifically, in this embodiment, the measuring device also has a port, which can be adjusted according to the measurement requirements when measuring other parameters of the microwave under test, so as to achieve more complete measurement of the microwave under test information.

[0035] The measurement principle of this invention is described below.

[0036] The EI spectrum acquired by the balanced detector can be observed with an oscilloscope. By analyzing the relationship between the EIT-AT splitting peak size and the microwave frequency, the resonance frequency of the microwave-coupled atomic transition channel at the current microwave power can be confirmed, and the frequency interval Δf of signal splitting under resonance conditions can be obtained. Furthermore, the microwave electric field intensity at the atomic vapor chamber can be calculated using the microwave Rabi frequency conversion formula. The calculation formula is: ; (1) Where h is Planck's constant. Let P be the transition dipole moment between Rydberg states; by setting the power of the microwave to be measured to P, the microwave electric field intensity corresponding to this microwave power is measured, and a linear calibration curve of microwave field intensity versus microwave power to be measured is further obtained. Assume the calibration curve is as follows: ; (2) The value is the slope of the relationship curve. The microwave electric field strength is then obtained through measurement. By using the linear calibration curve, the microwave power to be measured can be obtained.

[0037] In the atomic superheterodyne measurement model, the Rabi frequency of the microwave to be measured The Rabi frequency is much smaller than that of the local oscillator microwave. At that time, the detected laser transmission spectrum is: (3) To detect the average transmitted light intensity. This refers to the time-dependent oscillation signal in the transmission probe spectrum, i.e., the beat frequency signal displayed on the oscilloscope. The frequency corresponding to the beat frequency signal. The phase corresponding to the beat frequency signal. Transform to the frequency domain using Fourier transform. back, In frequency The amplitude at that point, . The total intrinsic gain coefficient in the atomic superheterodyne measurement method is used. The phase information of the microwave to be measured can be obtained by performing phase-sensitive detection on the probe laser transmission signal using formula (3).

[0038] Since the microwaves to be measured can enter the atomic gas cell from any direction, this embodiment of the invention uses three local oscillator microwaves to form a spatial coordinate system, enabling three-dimensional spatial measurement of the microwaves to be measured. Furthermore, this embodiment of the invention uses two probe beams for measurement, one vertically polarized and one horizontally polarized, resulting in a change in the beat frequency signal amplitude, which can form a comparison of the measurement signals.

[0039] Three local oscillator microwaves, A, B, and C, are orthogonally polarized, with their polarization directions along the X, Y, and Z axes, respectively, thus forming a spatial coordinate system. When local oscillator microwaves A, B, and C are applied, the microwave under test is horizontally polarized. Vertical polarization Individual outputs generate projections on the main axes of the three local oscillator microwaves. Because of the relationship between the local oscillator microwave polarization directions, the projection satisfies the following condition: (4) The three local oscillator microwaves have different frequencies, which will generate three heterodyne beat frequencies with the same microwave under test. The amplitude of the beat frequency signal... The relationship with the amplitude of the microwave to be measured is as follows: (5) Three local oscillator microwaves, A, C, and D, are orthogonally polarized, with their polarization directions along the X, Z, and Y axes, respectively, forming a spatial coordinate system. When local oscillator microwaves A, C, and D are applied, the output mode of the microwave under test remains unchanged, and projections are generated on the principal axes of the local oscillator microwaves. The relationship between the projections is as follows: (6) The amplitude of the generated beat frequency signal The relationship with the amplitude of the microwave to be measured is as follows: (7) When local oscillator microwaves A, B, and C are applied, , When the relative amplitudes are the same, at the atomic vapor cell , phase difference between Related to the parameters of the device, it can be specifically expressed as: ; (8) in, This represents the projection of the microwave under test along the polarization direction (i.e., the X-axis) of the local oscillator microwave A. The projection of the microwave under test along the polarization direction (i.e., the Y-axis) of the local oscillator microwave B. Phase difference at the atomic vapor cell This represents the projection of the microwave under test along the polarization direction (i.e., the X-axis) of the local oscillator microwave A. The projection of the microwave under test along the polarization direction (i.e., the Z-axis) of the local oscillator microwave C Phase difference at the atomic vapor cell; This represents the projection of the local oscillator microwave A and the microwave under test along the polarization direction (i.e., the X-axis) of the local oscillator microwave A. Phase difference at the atomic vapor cell This represents the phase difference between the local oscillator microwave A and the atomic vapor cell. This represents the phase difference between the local oscillator microwave B and the atomic vapor cell. This represents the projection of the local oscillator microwave B and the microwave under test along the polarization direction (i.e., the Y-axis) of the local oscillator microwave B. Phase difference at the atomic vapor cell; This represents the projection of the measured microwave along the polarization direction (i.e., the Z-axis) of the local oscillator microwave C. The phase difference between the microwave transmitting antenna and the atomic vapor pool; This represents the projection of the local oscillator microwave C and the microwave under test along the polarization direction of the local oscillator microwave C. The phase difference at the atomic vapor cell.

[0040] pass The microwave polarization angle to be measured can be obtained. The range, through the horizontal signal ( ) and vertical signal ( The specific polarization angle can be obtained by projecting along the polarization axis. .

[0041] (9) Specifically, the formula for calculating the polarization angle is: ; (10) Specifically, in this embodiment, according to the first formula in formula (5), the beat frequency signal can be used. Determine the horizontal polarization of the microwave under test And the second or third equation in formula (7) can be obtained through the beat frequency signal. or The vertical polarization of the microwave under test can be determined. ; By measuring the horizontal and vertical polarization information, the atomic vapor cell , The phase difference between the phases is used to obtain the polarization information of the microwave under test.

[0042] Example 2 Embodiment 2 of the present invention provides a microwave multi-information measurement method based on multi-local oscillator microwaves, according to... Figure 1 The illustrated implementation of a microwave multi-information measurement device based on multi-local oscillator microwaves, such as... Figure 5 As shown, it includes the following steps: Step 1: Measure the microwave intensity to be tested; including: A set of orthogonally polarized local oscillator microwaves is applied, and the signals are received by the first and second balanced detectors. The beat frequency signals in the two sets of received signals are analyzed to obtain the electric field strength E1 of the microwave under test. Another set of orthogonally polarized local oscillator microwaves is applied, and the electric field strength E2 of the microwave under test is obtained by spectrum analysis of the beat frequency signals of the first and second balanced detectors. By combining the electric field strengths E1 and E2, the electric field strength of the microwave under test can be obtained.

[0043] Step 2: Perform the measurement of the microwave frequency to be tested, including: A set of orthogonally polarized local oscillator microwaves is applied, and signals are received through the first and second balanced detectors. The frequency spectrum of the beat frequency signal in the two received signals is analyzed, the frequency of the local oscillator microwave is changed, and the frequency f1 of the microwave to be tested is determined based on the strongest beat frequency signal obtained. Another set of orthogonally polarized local oscillator microwaves is applied, and the signals are received through the first and second balanced detectors. The frequency spectrum of the beat frequency signal in the two received signals is analyzed, the frequency of the local oscillator microwave is changed, and the frequency f2 of the microwave to be measured is obtained based on the strongest beat frequency signal. By combining frequency f1 and frequency f2, the frequency of the microwave to be measured is determined; Step 3: Perform microwave phase measurement, including: A set of orthogonally polarized local oscillator microwaves is applied, and signals are received through the first and second balanced detectors. The beat frequency signals in the two sets of received signals are phase-sensitively detected to obtain the phase information of the two beat frequency signals. Another set of orthogonally polarized local oscillator microwaves is applied, and the signals are received through the first and second balanced detectors. The phase-sensitive detection of the beat frequency signals in the two sets of received signals is performed to obtain the phase information of the two beat frequency signals. By combining the phase information from the two measurements, the phase of the microwave under test is determined. Step 4: Perform microwave polarization measurement, including: Local oscillator microwave C, one of two sets of orthogonally polarized local oscillator microwaves (A and B) and another set of orthogonally polarized local oscillator microwaves (C and D), is received by a first balanced detector and a second balanced detector. The amplitude of the beat frequency signal in the two received signals is analyzed to obtain two horizontal polarizations. ; Local oscillator microwave A from one set of orthogonally polarized local oscillator microwaves A and B, and local oscillator microwaves C and D from another set of orthogonally polarized local oscillator microwaves, are received by a first balanced detector and a second balanced detector. The amplitude of the beat frequency signal in the two received signals is analyzed to obtain two vertical polarizations. ; Combining the horizontal and vertical polarization information from two measurements, the polarization angle of the microwave under test is calculated using the following formula: ; (11) in, Indicates the horizontal polarization at the location of the detection unit. With vertical polarization The phase difference between them.

[0044] Example 3 Embodiment 2 of the present invention provides a microwave multi-information measurement method based on multi-local oscillator microwaves, according to... Figure 1 The microwave multi-information measurement device based on multi-local oscillator microwaves shown includes the following steps: Step 1: Measure the microwave intensity to be tested; including: A set of orthogonally polarized local oscillator microwaves is applied, and the signals are received by the first and second balanced detectors. The beat frequency signals in the two sets of received signals are analyzed to obtain the electric field strength E1 of the microwave under test. Another set of orthogonally polarized local oscillator microwaves is applied, and the electric field strength E2 of the microwave under test is obtained by spectrum analysis of the beat frequency signals of the first and second balanced detectors. By combining the electric field strengths E1 and E2, the electric field strength of the microwave under test can be obtained.

[0045] This embodiment also includes a process for calibrating, adjusting, and evaluating the device parameters, as detailed below: S1-1. In this embodiment, local oscillator microwaves A and B and the microwave to be tested are first applied. The power of the microwave to be tested is set to P0, causing the EIT spectral line of the probe light to split into AT segments. The phenomenon is optimized. The transmission signal of the probe light is collected using an oscilloscope to obtain the frequency interval Δf of the signal splitting under resonance conditions. The microwave electric field intensity |E0| at the atomic vapor chamber is obtained by formula (1). The power of the microwave to be tested is modified several times, and its corresponding electric field intensity is measured. The linear calibration curve of the power of the microwave to be tested and the electric field intensity of the microwave to be tested is further obtained by formula (2).

[0046] S1-2. After locking the coupling light, observe the beat frequency signal. The transmission spectrum of the probe light is received through the first balanced detector 14 and the second balanced detector 15. The spectrum analyzer 17 receives the signals from the balanced detectors and performs spectrum analysis on the probe light after passing through the detection unit. The collected beat frequency signal is transmitted to the computing unit, and the electric field intensity E1 corresponding to the microwave power is obtained through a linear calibration curve.

[0047] S1-3. Next, stop applying local oscillator microwaves A and B, turn on local oscillator microwaves C and D, repeat step S1-2, observe the beat frequency signal again, and perform spectrum analysis on the transmitted laser spectrum to obtain the electric field intensity E2 corresponding to the microwave power.

[0048] S1-4. Compare the obtained electric field strengths E1 and E2 of the microwave under test. Using servo control, adjust the frequency and phase of the local oscillator microwave at the local oscillator signal generator, and adjust the laser parameters in the detection laser module and coupling laser module. Since the electric field strength of the simulated microwave under test is known, adjusting the parameters to minimize the error between the measured result and the known electric field strength is considered sufficient adjustment.

[0049] S1-5. Repeat steps S1-4 and S1-5 multiple times to simulate the known electric field strength of the microwave under test. After repeated measurements, calculate the average electric field strength of the microwave under test and obtain the measurement result and measurement error.

[0050] In this embodiment, a microwave signal is generated by the signal generator 11 to simulate the microwave under test. The microwave under test is emitted to the detection unit 12 from any direction; the beat frequency signal between the local oscillator microwave and the microwave under test is sensed by the atoms in the detection unit 12 and converted into a change in the intensity of the probe light. Because one probe light is vertically polarized and the other is horizontally polarized, in the superheterodyne measurement method, the EIT-AT spectrum is affected by the polarization matching of the light and the microwave. When the polarization directions of the microwave and the light are parallel, the AT splitting phenomenon is most obvious. During the measurement process, the clearer spectrum of the two spectra can be selected for analysis to improve the measurement accuracy.

[0051] Step 2: Perform the measurement of the microwave frequency to be tested, including: A set of orthogonally polarized local oscillator microwaves is applied, and signals are received through the first and second balanced detectors. The frequency spectrum of the beat frequency signal in the two received signals is analyzed, the frequency of the local oscillator microwave is changed, and the frequency f1 of the microwave to be tested is determined based on the strongest beat frequency signal obtained. Another set of orthogonally polarized local oscillator microwaves is applied, and the signals are received through the first and second balanced detectors. The frequency spectrum of the beat frequency signal in the two received signals is analyzed, the frequency of the local oscillator microwave is changed, and the frequency f2 of the microwave to be measured is obtained based on the strongest beat frequency signal. By combining frequencies f1 and f2, the frequency of the microwave to be measured is determined.

[0052] This embodiment also includes the process of calibrating and adjusting the device parameters and evaluating the measurement results, as detailed below: S2-1. The signal microwave and the local oscillator microwave have different frequencies, resulting in beat frequencies during transmission. By changing the frequencies of the local oscillator microwaves A and B, the balanced detectors 14 and 15 collect the transmission spectrum of the probe light. The beat frequency signal is obtained using a spectrum analyzer 17 and an oscilloscope 18. The collected data is transmitted to the computing unit, the beat frequency signal is analyzed, the frequency corresponding to the strongest beat frequency signal is found, and the frequency I of the microwave under test is obtained.

[0053] S2-2. Stop applying local oscillator microwaves A and B, turn on local oscillator microwaves C and D, change the frequency of local oscillator microwaves C and D, and perform spectrum analysis on the detection laser after passing through the detection unit again to obtain the beat frequency signal. Transmit the collected data to the calculation unit, find the frequency corresponding to the strongest beat frequency signal, and obtain the frequency 2 of the microwave to be measured.

[0054] S2-3. Compare the results of the measured microwave frequencies 1 and 2. Through servo control, adjust the frequency and phase of the local oscillator microwave at the local oscillator signal generator, and adjust the laser parameters in the detection laser module and coupling laser module. Since the frequency of the simulated microwave is known, adjusting the parameters to minimize the error between the measured result and the known frequency is considered to be in place.

[0055] S2-4. Repeat steps S2-2 and S2-3 multiple times. The frequency of the microwave to be measured is known. After repeated measurements, the average frequency of the microwave to be measured is calculated, and the measurement results and measurement errors are obtained.

[0056] Step 3: Perform microwave phase measurement, including: A set of orthogonally polarized local oscillator microwaves is applied, and signals are received through the first and second balanced detectors. The beat frequency signals in the two sets of received signals are phase-sensitively detected to obtain the phase information of the two beat frequency signals. Another set of orthogonally polarized local oscillator microwaves is applied, and the signals are received through the first and second balanced detectors. The phase-sensitive detection of the beat frequency signals in the two sets of received signals is performed to obtain the phase information of the two beat frequency signals. By combining the phase information from the two measurements, the phase of the microwave under test is determined.

[0057] This embodiment also includes the process of calibrating and adjusting the device parameters and evaluating the measurement results, as detailed below: S3-1. Adjust the frequencies of the local oscillator microwaves A and B to obtain the beat frequency signals of the microwave under test and the local oscillator microwaves A and B. Perform phase-sensitive detection on the probe laser transmission signal through the lock-in amplifier 16, and transmit the phase and other information of the beat frequency 1 to the computing unit for processing and analysis.

[0058] S3-2. Stop applying local oscillator microwaves A and B, turn on local oscillator microwaves C and D, obtain the beat frequency signals of the microwave to be tested and local oscillator microwaves C and D, perform phase-sensitive detection on the probe laser transmission signal again, and transmit the phase and other information of beat frequency 2 to the computing unit for processing and analysis. S3-3. The phase information of the beat frequency signal can be obtained through formula (3). The phase information of the local oscillator microwave is known. ,pass The phase of the microwave under test can be obtained. By comparing the phase of the microwave under test obtained from beat frequency 1 and beat frequency 2, the frequency and phase of the local oscillator microwave are adjusted at the local oscillator signal generator via servo control, and the laser parameters are adjusted in the detection laser module and the coupling laser module. Since the phase of the simulated microwave under test is known, adjusting the parameters to minimize the error between the measurement result and the known phase is considered to be in place.

[0059] S3-4. Repeat steps S3-2 and S3-3 multiple times. After repeated measurements, calculate the average phase value of the microwave under test and obtain the measurement result and measurement error.

[0060] Step 4: Perform microwave polarization measurement, including: Local oscillator microwave C, one of two sets of orthogonally polarized local oscillator microwaves (A and B) and another set of orthogonally polarized local oscillator microwaves (C and D), is received by a first balanced detector and a second balanced detector. The amplitude of the beat frequency signal in the two received signals is analyzed to obtain two horizontal polarizations. ; Local oscillator microwave A from one set of orthogonally polarized local oscillator microwaves A and B, and local oscillator microwaves C and D from another set of orthogonally polarized local oscillator microwaves, are received by a first balanced detector and a second balanced detector. The amplitude of the beat frequency signal in the two received signals is analyzed to obtain two vertical polarizations. ; Combining the horizontal and vertical polarization information from two measurements, the polarization angle of the microwave under test is calculated using the following formula: ;(12) in, Indicates the vertical polarization at the location of the detection unit. With horizontal polarization The phase difference between them.

[0061] This embodiment also includes the process of calibrating and adjusting the device parameters and evaluating the measurement results, as detailed below: S4-1. Simultaneously apply local oscillator microwaves A, B, and C, with the microwave under test horizontally polarized. 、 Vertical polarization With separate outputs and two independent stepped energy levels, the horizontal and vertical polarization of the microwave under test can be measured separately. Projections are generated on the principal axes of the three local oscillator microwaves. ,and Because of the placement of the microwave generator, the projection has a fixed relationship, which is expressed by formula (4). The three local oscillator microwaves are at different frequencies, which will generate six heterodyne beat frequencies ( ).

[0062] S4-2. Calibrate the local oscillator microwave to ensure equal amplitude at the atomic level. Observe the transmission spectrum of the probe laser using oscilloscope 18. Use the fast Fourier transform of the optical zero-difference output to obtain the signal peaks corresponding to the three beat frequencies of horizontal polarization and the three beat frequencies of vertical polarization. Perform spectrum analysis to obtain the beat frequency amplitude and the relative phase between beat frequencies. Transmit the collected beat frequency amplitude and the relative phase information between beat frequencies to the computing unit to obtain the relative amplitude and phase difference of the horizontal and vertical polarization projections of the microwave under test on the three main axes of the local oscillator microwave. The magnitude of the horizontal and vertical polarization can be determined by the relative amplitude projected onto each axis; the phase difference projected onto each axis can determine the angle between the horizontal and vertical polarization and each axis. The horizontal polarization of the microwave under test can be obtained using formulas (5), (8), and (9). and vertical polarization ; S4-3. Stop applying the local oscillator microwave B, turn on the local oscillator microwave D, and keep the output mode of the microwave under test unchanged. New projections will be generated on the principal axes of the three local oscillator microwaves. The fixed relationship of projection can be expressed by formula (6). Since the three local oscillator microwave frequencies are different, repeat step S4-2 to obtain another set of horizontal polarizations of the microwave under test. and vertical polarization .

[0063] S4-4. Compare the polarization information obtained from different step-type energy levels and local oscillator microwaves. Compare horizontal polarization information 1 with vertical polarization information 2, and horizontal polarization information 2 with vertical polarization information 1. Through servo control, adjust the frequency and phase of the local oscillator microwave at the local oscillator signal generator, and adjust the laser parameters in the detection laser module and coupling laser module. Since the polarization information of the simulated microwave under test is known, adjusting the parameters to minimize the error between the measurement result and the known polarization information is considered to be in place.

[0064] S4-5. The obtained horizontal and vertical polarization information of the microwave under test is calculated using formula (10) to obtain detailed polarization information of the microwave under test.

[0065] S4-6. Repeat steps S4-3 and S4-4 multiple times. The polarization information of the microwave under test is known. After repeated measurements, calculate the average value of the polarization information of the microwave under test and obtain the measurement result and measurement error.

[0066] S4-7. By rotating the microwave antenna under test, different polarization information is pre-acquired, and the results are tabulated. In subsequent measurements, the collected data can be compared with this table to quickly obtain polarization information.

[0067] Furthermore, this invention can also measure other parameters of the microwave under test. The device can be adjusted according to measurement requirements to achieve more complete measurement of the microwave information under test. For example, the directionality of the microwave under test: the angle of arrival can be calculated by the phase difference of the four local oscillator microwaves of the microwave under test. The phase difference is related to the spacing of the local oscillator microwaves and the incident angle, thus obtaining the direction information of the microwave under test. Measurements can be performed according to user needs. This is only an example of customized measurement. Specific details regarding the measurement of a certain parameter can be found in relevant patents and literature.

[0068] In summary, this invention proposes a microwave multi-information measurement device based on multiple local oscillator microwaves. By utilizing multiple orthogonal and independent local oscillator microwaves in conjunction with Rydberg atomic heterodyne detection technology, it achieves simultaneous high-precision measurement of the intensity, frequency, phase, and polarization of the microwave electric field under test. Multiple local oscillator channels are integrated using a dual-polarized RF horn, combined with a dual-optical-path laser excitation system. The frequency shift between laser beams I and J is detected, forming two independent sets of stepped energy levels. The polarization directions of lasers I and J are orthogonal and their spatial positions coincide, significantly reducing the space occupied by optical and RF components. Multiple local oscillator microwave frequencies are separated by a small frequency difference to project the signal under test. The beat frequency signal between the microwaves is used to directly extract the amplitude and phase difference of the electric field components in each direction, completing a high-sensitivity measurement. Therefore, the entire device and method have the advantages of small size, portability, simple operation, high measurement accuracy, and the ability to sequentially obtain multiple information about the microwave under test.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A microwave multi-information measurement device based on multi-local oscillator microwaves, characterized in that, include: The system includes a laser detection module, a laser coupling module, a signal detection module, a local oscillator signal generation module, and a signal processing module. The signal detection module includes a detection unit, a polarization beam splitter, a first balanced detector, and a second balanced detector; The detection laser module is used to output a first detection light, a second detection light, a first reference light, and a second reference light to the detection unit; wherein the first detection light is frequency-shifted, polarized orthogonal, and has the same optical path as the second detection light; the first reference light has the same frequency and polarization as the first detection light; and the second reference light has the same frequency and polarization as the second detection light. The coupling laser module is used to output a coupled light beam to the detection unit that is opposite in direction to the first and second detection lights; the coupled light is used to generate an EIT effect when it meets the first and second detection lights at the detection unit. The local oscillator signal generation module is used to output multiple local oscillator microwave signals with the same phase and a propagation path perpendicular to the beam path in the detection unit to the detection unit; The first probe light, the second probe light, the first reference light, and the second reference light are separated by a polarization beam splitter after passing through the detection unit. The first probe light and the first reference light are received by the first balanced detector, and the second probe light and the second reference light are received by the second balanced detector. The output signals from the first and second balanced detectors are used by the signal processing module to calculate the microwave information to be measured.

2. The microwave multi-information measurement device based on multi-local oscillator microwaves according to claim 1, characterized in that, The signal processing module calculates the microwave information to be tested, including the electric field strength, frequency, phase information, and polarization angle of the microwave.

3. The microwave multi-information measurement device based on multi-local oscillator microwaves according to claim 1, characterized in that, The detection laser module includes a detection laser and a beam splitting module. The beam splitting module includes a half-wave plate, a first polarizing beam splitter, an acousto-optic modulator, a first beam splitter, a second beam splitter, and a second polarizing beam splitter. The laser output from the detection laser is split into two beams after passing through the half-wave plate and the first polarizing beam splitter. One beam is vertically polarized light, which is frequency-shifted by the acousto-optic modulator and then split into a first detection beam and a first reference beam by the first beam splitter. The other beam is horizontally polarized light, which is reflected by the first mirror and then split into a second detection beam and a second reference beam by the second beam splitter. The horizontally polarized second detection beam is reflected by the fourth mirror and then combined with the vertically polarized first detection beam by the second polarizing beam splitter before entering the detection unit. The first reference beam and the second reference beam are reflected by the second mirror and the third mirror, respectively, and then incident on the detection unit parallel to the detection beam.

4. The microwave multi-information measurement device based on multi-local oscillator microwaves according to claim 3, characterized in that, The offset of the acousto-optic modulator is 180-200 MHz.

5. A microwave multi-information measurement device based on multi-local oscillator microwaves according to claim 1, characterized in that, The local oscillator signal generation module includes a local oscillator signal generator, a power divider, a phase compensator, and a transmitter. Multiple local oscillator microwave groups emitted by the local oscillator signal generator are transmitted to different transmitters via the power divider and the phase compensator, and then transmitted to the detection unit via the transmitters. The phase compensator is used to compensate for the initial phase of each microwave in each local oscillator microwave group to keep them consistent. Each transmitter is used to transmit one local oscillator microwave group, and each local oscillator microwave group includes two microwaves with orthogonal polarization.

6. The microwave multi-information measurement device based on multi-local oscillator microwaves according to claim 1, characterized in that, The signal processing module includes a lock-in amplifier, a spectrum analyzer, an oscilloscope, and a computing unit; the lock-in amplifier is used to extract the phase information carried by the beat frequency signals output by the first and second balanced detectors; the spectrum analyzer is used to perform spectrum analysis on the detection laser passing through the detection unit to obtain spectrum information; the oscilloscope is used to directly observe and store the beat frequency signals. The calculation unit is used to obtain the microwave information to be measured based on the beat frequency signal, phase information, and spectrum information.

7. A microwave multi-information measurement device based on multi-local oscillator microwaves according to claim 1, characterized in that, The detection unit is an alkali metal atomic vapor cell.

8. A microwave multi-information measurement method based on multi-local oscillator microwaves, implemented according to the microwave multi-information measurement device based on multi-local oscillator microwaves as described in claim 1, characterized in that, Includes the following steps: Step 1: Measure the microwave intensity to be tested; including: A set of orthogonally polarized local oscillator microwaves is applied, and the signals are received by the first and second balanced detectors. The beat frequency signals in the two sets of received signals are analyzed to obtain the electric field strength E1 of the microwave under test. Another set of orthogonally polarized local oscillator microwaves is applied, and the electric field strength E2 of the microwave under test is obtained by spectrum analysis of the beat frequency signals of the first and second balanced detectors. By combining the electric field strengths E1 and E2, the electric field strength of the microwave under test can be obtained. Step 2: Perform the measurement of the microwave frequency to be tested, including: A set of orthogonally polarized local oscillator microwaves is applied, and signals are received through the first and second balanced detectors. The frequency spectrum of the beat frequency signal in the two received signals is analyzed, the frequency of the local oscillator microwave is changed, and the frequency f1 of the microwave to be tested is determined based on the strongest beat frequency signal obtained. Another set of orthogonally polarized local oscillator microwaves is applied, and the signals are received through the first and second balanced detectors. The frequency spectrum of the beat frequency signal in the two received signals is analyzed, the frequency of the local oscillator microwave is changed, and the frequency f2 of the microwave to be measured is obtained based on the strongest beat frequency signal. By combining frequencies f1 and f2, the frequency of the microwave to be measured is determined; Step 3: Perform microwave phase measurement, including: A set of orthogonally polarized local oscillator microwaves is applied, and signals are received through the first and second balanced detectors. The beat frequency signals in the two sets of received signals are phase-sensitively detected to obtain the phase information of the two beat frequency signals. Another set of orthogonally polarized local oscillator microwaves is applied, and the signals are received through the first and second balanced detectors. The phase-sensitive detection of the beat frequency signals in the two sets of received signals is performed to obtain the phase information of the two beat frequency signals. By combining the phase information from the two measurements, the phase of the microwave under test is determined. Step 4: Perform microwave polarization measurement, including: Local oscillator microwave C, one of two sets of orthogonally polarized local oscillator microwaves (A and B) and another set of orthogonally polarized local oscillator microwaves (C and D), is received by a first balanced detector and a second balanced detector. The amplitude of the beat frequency signal in the two received signals is analyzed to obtain two horizontal polarizations. ; Local oscillator microwave A from one set of orthogonally polarized local oscillator microwaves A and B, and local oscillator microwaves C and D from another set of orthogonally polarized local oscillator microwaves, are received by a first balanced detector and a second balanced detector. The amplitude of the beat frequency signal in the two received signals is analyzed to obtain two vertical polarizations. ; Combining the horizontal and vertical polarization information from two measurements, the polarization angle of the microwave under test is calculated using the following formula: ； in, Indicates the horizontal polarization at the location of the detection unit. With vertical polarization The phase difference between them.

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