Broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device and method

Abstract

The invention relates to the technical field of electromagnetic signal spectrum analysis, and provides a broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device and method. The device comprises a mainboard, and a laser module, a local oscillator terahertz source, an atomic antenna module and a signal processing module which are connected with the mainboard. The laser module is used for generating detection laser and coupling laser which are input into the atom antenna module; the local oscillator terahertz source is used for providing a required local oscillator signal for the atomic antenna module to carry out superheterodyne receiving; the atomic antenna module is used for collimating two paths of input light and then enabling the light to enter an atomic gas chamber, and the detection laser passes through the atomic gas chamber and then is reflected by a dichroic mirror to enter a photodiode so as to convert a detection laser signal into an intermediate frequency signal; and the signal processing module is used for filtering and amplifying the intermediate-frequency signal, performing spectrum analysis to obtain an intermediate-frequency signal power spectrum, and performing spectrum splicing on the intermediate-frequency signal power spectrum and a local oscillator signal frequency corresponding to the time slot to obtain a to-be-measured electromagnetic field spectrum.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic signal spectrum analysis, and in particular to a broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device and method. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] Electromagnetic signal spectrum analysis technology is widely used in many fields such as communication testing, microwave / millimeter wave communication, satellite communication, remote sensing, radar, material analysis and detection, scientific research and teaching. As a mature basic measuring instrument, the traditional spectrum analyzer is mainly used to realize the spectrum analysis of microwave and millimeter wave frequency bands. The maximum operating frequency of commercially available spectrum analyzers can reach 110GHz. However, terahertz spectrum analysis requires the combination of traditional spectrum analyzers and frequency doubling modules. The measurement system is expensive and has limited sensitivity. The light intensity spectrum analyzer based on time-domain optics completes the spectrum measurement by loading the terahertz signal to be measured onto continuous light. The working bandwidth of the light intensity spectrum analyzer is much larger than that of the traditional spectrum analyzer, but due to factors such as the laser line width and detector bandwidth used, the frequency resolution of this technical route is not high. The electromagnetic field measurement method based on Rydberg atoms has the characteristics of high sensitivity, large working frequency band, high frequency resolution, high spatial resolution, and the measurement results can be directly traced back to basic physical constants. It has received widespread attention in recent years. This method can be used to achieve broadband and high-resolution electromagnetic signal spectrum analysis. However, most of the current electric field measurement systems based on Rydberg atoms are composed of lasers, frequency stabilization systems, electric field receiving modules, oscilloscopes, spectrometers and other instruments, and the measurement system needs to be built on an optical platform. The technology maturity is in the laboratory principle verification stage, and there are problems such as low overall integration, heavy weight, high power consumption and poor mobility. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned background technology, the present invention provides a broadband high-resolution fiber-integrated electromagnetic wave spectrum analysis device and method. The present invention adopts a fiber laser source to generate dual-wavelength laser, and the laser transmission from the laser source to the atomic antenna for receiving electromagnetic signals adopts an all-fiber solution. The atomic antenna adopts an integrated optical path design inside to reduce the influence of factors such as fiber coupling efficiency and external vibration on the measurement results of the device; the present invention utilizes a signal processing module to complete functions including laser control, frequency stabilization control and FFT, etc., to improve the system integration and realize the spectrum measurement and analysis of electromagnetic signals of any frequency within a broadband range.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A first aspect of the present invention provides a broadband, high-resolution, optical fiber-integrated electromagnetic wave spectrum analysis device.

[0007] A broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device, comprising: a main board, and a laser module, a local oscillator terahertz source, an atomic antenna module and a signal processing module all connected to the main board;

[0008] A laser module, used for generating a detection laser and a coupling laser input into the atomic antenna module;

[0009] A local oscillator terahertz source is used to provide the required local oscillator signal for the atomic antenna module to perform superheterodyne reception;

[0010] The atomic antenna module is used to collimate the two input lights and then enter the atomic gas chamber. After the detection laser passes through the atomic gas chamber, it is reflected by the dichroic mirror and enters the photodiode to convert the detection laser signal into an intermediate frequency signal.

[0011] The signal processing module is used to filter and amplify the intermediate frequency signal, perform spectrum analysis to obtain the intermediate frequency signal power spectrum, and perform spectrum splicing with the local oscillator signal frequency corresponding to the time slot to obtain the electromagnetic field spectrum to be measured.

[0012] Furthermore, the laser module includes a first laser source, a second laser source, an EOM module, a saturated absorption frequency stabilization module, an EIT frequency stabilization module and a frequency shift module. The first laser source is used to generate a detection laser, which is divided into two paths, one of which is connected to the atomic antenna module, and the other is divided into two paths after being modulated by the EOM module, and enters the saturated absorption frequency stabilization module and the EIT frequency stabilization module respectively; the second laser source is used to generate a coupling laser, which is divided into two paths, one of which enters the EIT frequency stabilization module, and the other enters the atomic antenna module through the frequency shift module; the two paths of light entering the EIT frequency stabilization module enter the signal processing module after being processed; the saturated absorption frequency stabilization module and the EIT frequency stabilization module generate an error signal after outputting a spectral signal, and send the error signal to the signal processing module; the saturated absorption frequency stabilization module and the EIT frequency stabilization module output a spectral signal to the frequency stabilization control circuit in the signal processing module, the frequency stabilization control circuit demodulates the received signal to generate an error signal, and sends the error signal to the laser control module to achieve frequency stabilization.

[0013] Furthermore, the atomic antenna module includes a first collimation head, a second collimation head, a first PBS polarization beam splitter prism, a second PBS polarization beam splitter prism, an atomic gas chamber, a dichroic mirror and a photodiode. One detection laser entering the atomic antenna module sequentially enters the atomic gas chamber through the first collimation head and the first PBS polarization beam splitter prism, and another coupling laser entering the atomic antenna module sequentially enters the atomic gas chamber through the second collimation head and the second PBS polarization beam splitter prism. The detection laser passing through the atomic gas chamber is reflected by the dichroic mirror and converted into an electrical signal by the photodiode. The electrical signal is the required intermediate frequency signal.

[0014] Furthermore, the signal processing module includes a laser control module, which is connected to the first laser source and the second laser source in the laser module and is used to change the laser power and wavelength output by the first laser source and the second laser source.

[0015] Furthermore, the signal processing module also includes a frequency stabilization control circuit, which is connected to the laser control module and is used to generate the radio frequency signal required for the operation of the EOM module, generate an error signal after receiving the spectral signals output by the saturated absorption frequency stabilization module and the EIT frequency stabilization module, and send the error signal to the laser control module.

[0016] Furthermore, the signal processing module also includes a frequency shift control module for generating a radio frequency signal required for the AOM in the frequency shift module in the laser module to work.

[0017] Furthermore, the signal processing module also includes a preamplifier module, which is connected to the photodiode in the atomic antenna module, filters and amplifies the intermediate frequency signal output by the photodiode and then sends it to the FFT module, so that the FFT module performs spectrum analysis on the signal output by the preamplifier module to obtain the intermediate frequency signal power spectrum.

[0018] Furthermore, the signal processing module also includes a power supply module for supplying power to each module.

[0019] Furthermore, the device also includes a display module for displaying the electromagnetic field spectrum to be measured, and the display module is connected to the mainboard.

[0020] A second aspect of the present invention provides a broadband, high-resolution, fiber-integrated electromagnetic wave spectrum analysis method.

[0021] A broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis method, comprising:

[0022] A laser module is used to generate a detection laser and a coupling laser input into the atomic antenna module;

[0023] A local oscillator terahertz source is used to provide the required local oscillator signal for superheterodyne reception of the atomic antenna module;

[0024] The atomic antenna module is used to collimate the two input lights and then enter the atomic gas chamber. The detection laser passes through the atomic gas chamber and is reflected by the dichroic mirror into the photodiode to convert the detection laser signal into an intermediate frequency signal.

[0025] After filtering and amplifying the intermediate frequency signal using the signal processing module, spectrum analysis is performed to obtain the intermediate frequency signal power spectrum, which is then spectrally spliced ​​with the local oscillator signal frequency corresponding to the time slot to obtain the electromagnetic field spectrum to be measured.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention adopts a fiber laser source to generate the dual-wavelength laser required for measurement, and the laser transmission from the laser source to the terahertz receiving module where the atomic gas chamber is located adopts an all-fiber solution to reduce the influence of external vibration, air flow and other factors on the system. Since the laser propagation path in the gas chamber must be free space, in order to avoid the influence of fiber coupling efficiency on the measurement results, the terahertz receiving module adopts an integrated optical path design. After the two optical fiber lights are connected to the terahertz receiving module, they are converted into spatial light and pass through the gas chamber in the reverse common path. The detection light is directly received by the photodiode in the receiving module, ensuring the miniaturization requirements of the entire module while ensuring the detection efficiency. The present invention uses a signal processing module including laser control, frequency stabilization control and FFT module to replace the instruments used in other solutions, further improve the system integration and can realize the spectrum measurement and analysis of terahertz fields of any frequency in a broadband range by synchronously controlling the laser wavelength, the local oscillator terahertz field frequency, and the FFT module data acquisition and processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0029] Figure 1 is a structural diagram of a terahertz coherent detection and spectrum analysis device based on room temperature atoms shown in the present invention;

[0030] Figure 2 It is a structural diagram of a broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device shown in the present invention;

[0031] Figure 3 is a structural diagram of an integrated optical path atomic antenna module shown in the present invention;

[0032] Figure 4 is a flow chart of spectrum analysis shown in the present invention;

[0033] Figure 5 is a schematic diagram of spectrum analysis results shown in the present invention;

[0034] Among them, 1. Laser module, 1-1. First laser source, 1-2. Second laser source, 1-3. EOM module, 1-4. Saturated absorption frequency stabilization module, 1-5. EIT frequency stabilization module, 1-6. Frequency shift module, 2. Signal processing module, 2-1. Laser control module, 2-2. Frequency stabilization control circuit, 2-3. Frequency shift control module, 2-4. FFT module, 2-5. Preamplifier module, 2-6. Main board, 2-7. Power supply module, 3. Atomic antenna module, 3-1. First collimator head, 3-2. First PBS polarization beam splitter prism, 3-3. Atomic gas chamber, 3-4. Dichroic mirror, 3-5. Second PBS polarization beam splitter prism, 3-6. Second collimator head, 3-7. Photodiode, 4. Local oscillator terahertz source, 5. Display module. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0036] It should be noted that the following detailed descriptions are all illustrative and intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0037] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0038] It should be noted that the flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the methods and systems according to various embodiments of the present disclosure. It should be noted that each box in the flowchart or block diagram can represent a module, a program segment, or a part of a code, and the module, program segment, or a part of a code may include one or more executable instructions for implementing the logical functions specified in each embodiment. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, or they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the flowchart and / or block diagram, and the combination of boxes in the flowchart and / or block diagram can be implemented using a dedicated hardware-based system that performs a specified function or operation, or can be implemented using a combination of dedicated hardware and computer instructions.

[0039] By analyzing domestic and foreign literature, patents and products related to this technology, it is found that the existing more mature spectrum analysis devices include light intensity spectrum analyzers based on time-domain optics and spectrum analysis systems based on traditional spectrum analyzers. The spectrum resolution of light intensity spectrum analyzers can only reach the MHz level, and the sensitivity of traditional spectrum analyzers in the terahertz band is limited. Both technical routes cannot meet the large bandwidth and high spectrum resolution requirements proposed by various application scenarios.

[0040] In recent years, terahertz spectrum analysis methods and devices based on Rydberg atoms have received widespread attention. Rydberg atoms refer to atoms whose outermost electrons are excited to a highly excited state, the Rydberg state. Due to the large radius of Rydberg atoms, the small binding of the outermost electrons by the atomic core, the high polarizability and the large AC transition dipole moment, they are extremely sensitive to external electromagnetic fields, especially electric fields that resonate with Rydberg transitions, and can achieve high-sensitivity field strength measurements. The frequency of the electric field that resonates with the Rydberg atomic transition covers 0GHz to 1.1THz, so the operating frequency of the electric field measurement device based on Rydberg atoms can cover microwave, millimeter wave and sub-terahertz frequency bands. The preparation of hot Rydberg atoms is usually completed by filling alkali metal atomic vapor. When an external electric field acts on the Rydberg atom, the Rydberg energy level undergoes frequency shift or splitting due to the AC-Stark effect. By using the nonlinear quantum coherence effect under the interaction between light and atoms, the electromagnetically induced transparency effect (EIT), the change of the Rydberg energy level can be read out, and the measurement of the electromagnetic field can be converted into the measurement of the transmitted light field of the Rydberg atom. When a strong local oscillator field with similar frequency and a weak field to be measured act on the Rydberg atom, the Rydberg energy level will be perturbed and oscillated, and the amplitude, phase and frequency of the electromagnetic field to be measured will be modulated into the transmitted light field of the Rydberg atom. By receiving and processing the light field, the spectrum analysis of the electromagnetic field to be measured can be completed.

[0041] like Figure 1 As shown, the terahertz coherent detection and spectrum analysis device based on room temperature atoms includes: a detection light laser, an atomic gas chamber, a dichroic mirror, a coupled light laser, a photodetector, an oscilloscope, and a terahertz differential signal generator. The atomic gas chamber is used to provide cesium atomic gas under room temperature saturated vapor pressure. The detection light and the coupled light are collinearly and reversely incident on the atomic gas chamber to prepare the cesium atomic gas to the Rydberg state and produce an electromagnetically induced transparency effect. The error signal obtained by demodulation of the phase-locked amplifier is then used to lock the laser frequencies of the detection light and the coupled light. The photodetector is used to receive the detection light signal, and the optical signal is converted into an electrical signal and entered into the oscilloscope of the signal module, as well as the spectrum analysis unit and the phase-sensitive detection amplifier unit. The electric field intensity, frequency and phase information of the terahertz wave can be detected simultaneously.

[0042] Most systems use free-space transmission of the laser required for Rydberg atom preparation, which needs to be built on an optical platform. There are problems such as large size of the device, inconvenient movement, complicated optical devices used in the laser transmission path, and easy to be affected by the outside world. Some systems are built based on fiber-optic integrated air chambers. Due to the large differences in the wavelengths of the lasers used in the measurement process, there are no mature products for common devices such as circulators in the system, and the customization process is difficult and the insertion loss is large. In addition, the laser control circuits, data acquisition and signal processing devices used in each scheme are mostly external devices. During the test, each device needs to be operated separately, resulting in low overall integration of the device and high requirements on the professional level of the operator. The spectrum analysis methods in the above schemes are mostly more suitable for receiving and analyzing electromagnetic signals with known center frequencies. If the spectrum analysis of unknown signals is to be completed, it will take a long time and be difficult.

[0043] To this end, the present invention provides a broadband high-resolution fiber-integrated electromagnetic wave spectrum analysis device and method, which uses a fiber laser source to generate dual-wavelength lasers, and the laser transmission from the laser source to the atomic antenna for electromagnetic signal reception adopts an all-fiber solution. The atomic antenna adopts an integrated optical path design to reduce the influence of factors such as fiber coupling efficiency and external vibration on the device measurement results; the present invention uses a signal processing module to complete functions including laser control, frequency stabilization control, and FFT, etc., to improve the system integration, and realize the spectrum measurement and analysis of electromagnetic signals of any frequency within a broadband range. The present invention is described in detail through several embodiments below:

[0044] Embodiment 1

[0045] like Figure 2 As shown, this embodiment provides a broadband high-resolution fiber-integrated electromagnetic wave spectrum analysis device, including: a laser module 1, a signal processing module 2, an atomic antenna module 3, a local oscillator terahertz source 4 and a display module 5.

[0046] The laser module 1 includes a first laser source 1-1, a second laser source 1-2, an EOM module 1-3, a saturated absorption frequency stabilization module 1-4, an EIT frequency stabilization module 1-5, and a frequency shift module 1-6. The first laser source 1-1 and the second laser source 1-2 are both fiber laser source modules, which respectively generate a detection laser with a wavelength of about 852nm and a coupling laser with a wavelength of 511nm to 517nm. The detection light is divided into two paths, one of which is directly connected to the atomic antenna module 3, and the other is modulated by the electro-optical modulator of the EOM module 1-3 and connected to the saturated absorption frequency stabilization module 1-4 and the EIT frequency stabilization module 1-5. The coupling laser is divided into two paths, one of which is used for the EIT frequency stabilization module 1-5, and the other is connected to the atomic antenna module 3 after passing through the frequency shift module 1-6.

[0047] The specific structure of the atomic antenna module 3 is as follows Figure 3, the module is a multi-optical element integrated optical circuit. The detection laser coupling laser is collimated by the first collimator 3-1 and the second collimator 3-6, and then purified by the first PBS polarization splitter prism 3-2 and the second PBS polarization splitter prism 3-5, and then passes through the atomic gas chamber 3-3 filled with cesium atoms in the reverse direction. The detection laser passing through the atomic gas chamber 3-3 is reflected by the dichroic mirror 3-4 and converted into an electrical signal by the photodiode 3-7. The local oscillator signal required for superheterodyne reception of the atomic antenna module 3 is generated by the local oscillator terahertz source 4.

[0048] The laser control module 2-1 in the signal processing module 2 is connected to the first laser source 1-1 and the second laser source 1-2 in the laser module 1 to change the laser power and wavelength output by the first laser source 1-1 and the second laser source 1-2. The frequency stabilization control circuit 2-2 generates the radio frequency signal required for the operation of the EOM module 1-3, and after receiving the spectrum signal output by the saturated absorption frequency stabilization module 1-4 and the EIT frequency stabilization module 1-5, the spectrum is demodulated to generate an error signal, and the error signal is sent to the laser control module 2-1 after passing through the frequency stabilization control circuit 2-2 to achieve two-wavelength laser frequency stabilization. The frequency shift control module 2-3 generates the radio frequency signal required for the operation of the AOM in the frequency shift module 1-6. The preamplifier module 2-5 is connected to the photodiode 3-7 in the atomic antenna module 3 to filter and amplify the output signal of the photodiode 3-7. The FFT module 2-4 completes the spectrum analysis. The main board 2-6 is connected to the local oscillator terahertz source 4, the laser control module 2-1, the frequency shift control module 2-3, the frequency stabilization control circuit 2-2, the FFT module 2-4, etc., and reads the parameters of each module and the FFT spectrum analysis results and sends them to the display module 5, and distributes the instructions read by the user interaction interface to each module. The power supply module 2-7 supplies power to each module. Among them, the AOM is used to change the wavelength of the light after frequency stabilization so that the system works at the highest sensitivity point.

[0049] Under the joint action of the two-way frequency-stabilized laser output by the laser module 1, the atom is excited to the Rydberg state. Due to the quantum coherence effect, the population of the first excited state is zero at this time. The wavelength of the coupled light is scanned to obtain the detection light transmission spectrum, and the transmission peak, i.e., the EIT signal, can be observed. When the laser wavelength range used is 511-517nm, the corresponding Rydberg transition resonance frequency points are distributed in 0.02-0.5THz, and the atom can achieve superheterodyne reception at any frequency point in the frequency range. Under the action of the strong local oscillator field, the Rydberg energy level undergoes frequency shift or splitting. Under the joint action of the field to be measured and the local oscillator field, the Rydberg energy level undergoes perturbation oscillation. At the near-resonance laser wavelength, the intensity of the detection laser passing through the atomic gas chamber changes sinusoidally with time. The atom modulates the frequency, phase, amplitude and other information of the field to be measured to the transmitted detection light, thereby achieving superheterodyne reception of the field to be measured. The intermediate frequency signal can be obtained by converting the transmitted detection light into an electrical signal using a photodiode 3-7. The frequency of the intermediate frequency signal is the frequency difference between the two electromagnetic fields, the initial phase is the initial phase difference between the two electromagnetic fields, and the amplitude is proportional to the amplitude of the electromagnetic field to be measured. After filtering and amplifying the intermediate frequency signal, it is sent to the FFT module 2-4 for spectrum analysis. The specific analysis process is as follows: Figure 4 As shown. The mainboard 2-6 is used to synchronously trigger the change of the local oscillator source frequency, and the FFT module 2-4 collects and processes. The FFT module 2-4 transforms the signal in each time slot to obtain the intermediate frequency signal power spectrum, and performs spectrum splicing with the local oscillator terahertz signal frequency corresponding to the time slot, thereby obtaining the electromagnetic field spectrum to be measured. In view of the shortcomings of the existing electromagnetic signal spectrum analysis method, the present invention proposes a spectrum analysis method based on Rydberg atoms that is applicable to microwave, millimeter wave and terahertz bands, and solves the problem of high-sensitivity, high-resolution and wide-band spectrum analysis.

[0050] Taking the spectrum analysis of the terahertz field in the frequency range of 158GHz to 160GHz as an example, the laser control module 2-1 is used to set the coupled laser wavelength to 511.9340nm, and the output frequency of the fundamental frequency microwave source in the local oscillator terahertz source 4 is scanned. The scanning range is 13.17GHz to 13.33GHz, and the scanning step is 40kHz. The microwave is input into the frequency doubling module to generate a terahertz local oscillator source. The trigger signal simultaneously triggers the change of the microwave source frequency and the FFT data acquisition to obtain the power spectrum of the intermediate frequency signal under the action of the local oscillator terahertz field of different frequencies. After the mainboard reads the output power spectrum of the FFT module 2-4 and the signal frequency in the microwave source, the spectrum splicing is completed to obtain the following Figure 5 The signal shown is sent to the display module 5 to complete the spectrum analysis function. The wavelength of the coupled laser is changed by using the frequency shift module 1-6 to optimize the measured signal. The spectrum resolution of this method can reach 10Hz and the working frequency bandwidth can reach 0.5THz.

[0051] The electromagnetic signal receiving device of the present invention adopts a laser transmission solution combining optical fiber and integrated optical circuit as a whole, which reduces the loss in the laser transmission process, ensures the stability of the measurement results of the device and meets the miniaturization requirements; the atomic antenna has an integrated optical circuit to ensure that the detection light passing through the atomic gas chamber is received by the photodiode as much as possible, meets the miniaturization requirements and improves the detection efficiency.

[0052] The present invention proposes a signal acquisition and processing module including laser control, frequency stabilization control and FFT module, which can cooperate with other modules to realize terahertz spectrum analysis with a wide working range and high spectrum resolution, thereby improving the integration level compared with other devices.

[0053] Embodiment 2

[0054] This embodiment provides a broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis method, including:

[0055] A laser module is used to generate a detection laser and a coupling laser input into the atomic antenna module;

[0056] A local oscillator terahertz source is used to provide the required local oscillator signal for superheterodyne reception of the atomic antenna module;

[0057] The atomic antenna module is used to collimate the two input lights and then enter the atomic gas chamber. The detection laser passes through the atomic gas chamber and is reflected by the dichroic mirror into the photodiode to convert the detection laser signal into an intermediate frequency signal.

[0058] After filtering and amplifying the intermediate frequency signal using the signal processing module, spectrum analysis is performed to obtain the intermediate frequency signal power spectrum, which is then spectrally spliced ​​with the local oscillator signal frequency corresponding to the time slot to obtain the electromagnetic field spectrum to be measured.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device, characterized in that: It includes: a main board, and a laser module, a local oscillator terahertz source, an atomic antenna module and a signal processing module all connected to the main board; A laser module, used for generating a detection laser and a coupling laser input into the atomic antenna module; A local oscillator terahertz source is used to provide the required local oscillator signal for the atomic antenna module to perform superheterodyne reception; The atomic antenna module is used to collimate the two input lights and then enter the atomic gas chamber. After the detection laser passes through the atomic gas chamber, it is reflected by the dichroic mirror and enters the photodiode to convert the detection laser signal into an intermediate frequency signal. The signal processing module is used to filter and amplify the intermediate frequency signal, perform spectrum analysis to obtain the intermediate frequency signal power spectrum, and perform spectrum splicing with the local oscillator signal frequency corresponding to the time slot to obtain the electromagnetic field spectrum to be measured.

2. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The laser module includes a first laser source, a second laser source, an EOM module, a saturated absorption frequency stabilization module, an EIT frequency stabilization module and a frequency shift module. The first laser source is used to generate a detection laser, which is divided into two paths, one of which is connected to the atomic antenna module, and the other is divided into two paths after being modulated by the EOM module, and enters the saturated absorption frequency stabilization module and the EIT frequency stabilization module respectively; the second laser source is used to generate a coupling laser, which is divided into two paths, one of which enters the EIT frequency stabilization module, and the other enters the atomic antenna module through the frequency shift module; the two paths of light entering the EIT frequency stabilization module enter the signal processing module after being processed; the saturated absorption frequency stabilization module and the EIT frequency stabilization module output spectral signals to the frequency stabilization control circuit in the signal processing module, and the frequency stabilization control circuit demodulates the received signal to generate an error signal, and sends the error signal to the laser control module to achieve frequency stabilization.

3. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The atomic antenna module comprises a first collimation head, a second collimation head, a first PBS polarization beam splitter prism, a second PBS polarization beam splitter prism, an atomic gas chamber, a dichroic mirror and a photodiode. One detection laser entering the atomic antenna module sequentially passes through the first collimation head and the first PBS polarization beam splitter prism into the atomic gas chamber. Another coupling laser entering the atomic antenna module sequentially passes through the second collimation head and the second PBS polarization beam splitter prism into the atomic gas chamber. The detection laser passing through the atomic gas chamber is reflected by the dichroic mirror and then converted into an electrical signal by the photodiode. The electrical signal is the required intermediate frequency signal.

4. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The signal processing module comprises a laser control module, which is connected to the first laser source and the second laser source in the laser module and is used to change the laser power and wavelength output by the first laser source and the second laser source.

5. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 4, characterized in that: The signal processing module also includes a frequency stabilization control circuit, which is connected to the laser control module and is used to generate a radio frequency signal required for the operation of the EOM module, generate an error signal after receiving the spectral signals output by the saturated absorption frequency stabilization module and the EIT frequency stabilization module, and send the error signal to the laser control module.

6. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The signal processing module also includes a frequency shift control module, which is used to generate a radio frequency signal required for the AOM in the frequency shift module in the laser module to work.

7. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The signal processing module also includes a preamplifier module, which is connected to the photodiode in the atomic antenna module, filters and amplifies the intermediate frequency signal output by the photodiode and then sends it to the FFT module, so that the FFT module performs spectrum analysis on the signal output by the preamplifier module to obtain the intermediate frequency signal power spectrum.

8. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The signal processing module also includes a power supply module, which is used to supply power to each module.

9. The broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis device according to claim 1, characterized in that: The device also includes a display module for displaying the electromagnetic field spectrum to be measured, and the display module is connected to the mainboard.

10. A broadband high-resolution optical fiber integrated electromagnetic wave spectrum analysis method, characterized in that: include: A laser module is used to generate a detection laser and a coupling laser input into the atomic antenna module; A local oscillator terahertz source is used to provide the required local oscillator signal for superheterodyne reception of the atomic antenna module; The atomic antenna module is used to collimate the two input lights and then enter the atomic gas chamber. The detection laser passes through the atomic gas chamber and is reflected by the dichroic mirror into the photodiode to convert the detection laser signal into an intermediate frequency signal. After filtering and amplifying the intermediate frequency signal using the signal processing module, spectrum analysis is performed to obtain the intermediate frequency signal power spectrum, which is then spectrally spliced ​​with the local oscillator signal frequency corresponding to the time slot to obtain the electromagnetic field spectrum to be measured.

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