A method and apparatus for receiving Rydberg atoms with electromagnetic interference resistance

Abstract

The application relates to the technical field of electromagnetic detection, in particular to a Rydberg atom receiving device and method capable of resisting electromagnetic interference. The device comprises two parallel-plate waveguide atom probes integrated with optical fiber air chambers, an 852nm frequency stabilization module, a 509nm frequency stabilization module and three microwave sources; the three microwave sources are respectively used for generating local field signals, signal field signals and interference field signals; one alkali metal atom air chamber is embedded in each of the two parallel-plate waveguide atom probes, wherein the first alkali metal atom air chamber in the first parallel-plate waveguide atom probe receives the local field signals, the signal field signals and the interference field signals, mixes the local field signals and the signal field signals to generate intermediate frequency signals, and the second parallel-plate waveguide atom probe is used for realizing signal anti-interference through compensation of alternating current Stark energy shift; the device has simple structure and high sensitivity, can effectively improve the anti-interference capability of microwave signal detection, and ensures the signal detection precision and reliability of the device in a complex electromagnetic environment.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic detection technology, and in particular to a Rydberg atom receiving device and method that resists electromagnetic interference. Background Technology

[0002] With the increasing complexity of modern battlefield environments, traditional electromagnetic detection technologies face severe challenges. Especially in complex electromagnetic environments such as high-power microwave weapons, ultra-wideband white noise jamming, and forwarding jamming, existing microwave signal detection technologies often struggle to accurately detect and identify target signals. The presence of these interference sources renders traditional electronic warfare technologies significantly weak in anti-jamming capabilities, making them unsuitable for the demands of modern battlefields.

[0003] Existing microwave detection technologies often fail to effectively distinguish between target signals and interference signals when facing the aforementioned interference sources, resulting in a significant reduction in the accuracy and reliability of signal detection. Traditional electronic radar systems have inherent design limitations, making them ill-suited to the demands of modern battlefields for high sensitivity and strong anti-jamming capabilities.

[0004] Traditional electronic warfare jamming and anti-jamming technologies have developed in parallel, but in the "spear and shield" game, they have not yet achieved an ideal anti-jamming technology advantage, and there is an urgent need for a new generation of electromagnetic detection technology to break through this problem.

[0005] In recent years, next-generation radio receiving systems based on Rydberg atoms have gained popularity in the scientific and industrial communities due to their advantages such as high sensitivity, self-calibration capability, ultra-wideband operating frequency band covering DC to terahertz, ease of integration, and immunity to traditional antenna size effects. These advantages make them highly suitable for radio sensing and detection. In particular, their all-optical readout method possesses significant anti-interference potential, with an atomic instantaneous bandwidth of approximately 10MHz. The increased Q-value under high-frequency interference provides good suppression of external interference signals, potentially leading to a disruptive impact on traditional electronic radar technology. Summary of the Invention

[0006] In view of this, the present invention proposes a Rydberg atom receiving method and device for resisting electromagnetic interference. It has a simple structure, high sensitivity, effectively improves the anti-interference capability of microwave signal detection, and ensures the accuracy and reliability of signal detection in complex electromagnetic environments.

[0007] The present invention solves the above problems through the following technical means:

[0008] In a first aspect, this invention proposes a Rydberg atom receiving device resistant to electromagnetic interference, comprising two integrated fiber optic gas chambers with parallel-plate waveguide atom probes, an 852nm frequency stabilization module, a 509nm frequency stabilization module, and three microwave sources; wherein...

[0009] Three microwave sources are used to generate the local oscillator field signal, the signal field signal, and the interference field signal, respectively.

[0010] The 852nm frequency stabilization module is used to provide two 852nm lasers;

[0011] The 509nm frequency stabilization module is used to provide two 509nm lasers;

[0012] Two parallel plate waveguide atomic probes each have an alkali metal atom gas cell embedded in them. The first alkali metal atom gas cell in the first parallel plate waveguide atomic probe receives the local oscillator signal, the signal field signal, and the interference field signal. It mixes the local oscillator signal and the signal field signal to generate an intermediate frequency signal. The second parallel plate waveguide atomic probe is used to achieve signal anti-interference by compensating for AC Stark energy shift.

[0013] Furthermore, each of the parallel plate waveguide atomic probes includes two opposing optical fiber pigtails connected to the alkali metal atomic gas cell, and also includes a parallel plate waveguide for embedding the alkali metal atomic gas cell.

[0014] Furthermore, the parallel plate waveguide is made of copper, with one end tilted outward to form an open port, which is used to receive signals into the parallel plate waveguide.

[0015] Furthermore, the alkali metal atom gas chamber is a cuboid gas chamber made of high borosilicate glass, filled with Cs atoms, and fixed in the parallel plate waveguide by a support rod made of Teflon material.

[0016] Furthermore, the device also includes a photodetector, an oscilloscope, and a spectrum analyzer;

[0017] The photodetector is used to detect intermediate frequency signals;

[0018] The oscilloscope is used to observe the frequency lock of the 509nm frequency stabilization module;

[0019] The spectrum analyzer is used to observe and record the signal-to-noise ratio of intermediate frequency signals.

[0020] Furthermore, the device also includes a power divider and a horn, wherein the power divider is used to input both the signal field signal and the interference field signal into the horn, and the horn is used to couple the signal field signal and the interference field signal into the open port.

[0021] Furthermore, one 852nm laser from the 852nm frequency stabilization module and one 509nm laser from the 509nm frequency stabilization module are respectively incident into the first alkali metal atom gas cell through two oppositely arranged optical fiber pigtails to excite Rydberg atoms and lock the 852nm laser and the 509nm laser.

[0022] The other 852nm laser from the 852nm frequency stabilization module and the other 509nm laser from the 509nm frequency stabilization module are incident on the second parallel plate waveguide atomic probe, which has no signal feed, and the 509nm laser is locked.

[0023] On the other hand, the present invention also proposes a Rydberg atom receiving method resistant to electromagnetic interference, comprising the following steps:

[0024] Step 101: Place two Cs atom gas cells in two parallel plate waveguides. One gas cell is embedded in the parallel plate waveguide for measurement and is fed with a local oscillator signal via a coaxial cable. The other gas cell is embedded in the parallel plate waveguide for laser frequency locking and is not fed with a signal.

[0025] Step 102: The probe light and the coupling light are reversed and injected into the Cs atom gas cell to excite the Rydberg atoms;

[0026] Step 103: The interference signal and the signal field signal are transmitted to the two Cs atom gas cells through the horn. At this time, the Rydberg atoms act as spatial mixers, and the EIT-AT spectrum is modulated by the intermediate frequency signal generated by the mixing.

[0027] Step 104: The signal anti-interference capability can be observed by collecting the intermediate frequency signal through a photodetector.

[0028] Further, step 102 specifically includes:

[0029] Using optical fibers, the probe light and coupling light generated by two tunable lasers are respectively injected into the atomic cluster from both ends of the Cs atomic gas cell. The probe light and coupling light overlap inside the atomic cluster, and under the combined action of the probe light and coupling light, an electromagnetically induced transparent window is formed.

[0030] Furthermore, step 103 specifically includes:

[0031] Two microwave sources are used to generate two microwave signals, which are then transmitted to a speaker via a power divider. The speaker then illuminates both microwave signals onto a parallel plate waveguide atomic probe. One microwave signal is a signal field signal, which differs from the local oscillator signal by 10 kHz and has a power of -18 dBm. The signal field and the local oscillator field are mixed in a Cs atomic gas chamber to generate an intermediate frequency signal carrying information. The other microwave signal is an interference field signal, which provides a high-frequency, high-power interference signal to test the anti-interference capability of the intermediate frequency signal.

[0032] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0033] 1. Improved anti-interference capability: By optimizing the design of the Rydberg atomic heterodyne receiver and introducing an AC Stark effect compensation mechanism, this invention significantly improves the anti-interference capability of microwave signal detection.

[0034] 2. Enhanced signal detection accuracy: By utilizing parallel plate waveguide technology, this invention enhances the intermediate frequency signal strength and improves the ability to measure the phase and amplitude of the signal field, thereby enhancing the accuracy of signal detection.

[0035] 3. Adaptable to complex electromagnetic environments: The technical solution of this invention is particularly suitable for complex electromagnetic environments such as modern battlefields, and can effectively cope with challenges such as high-power microwave weapons, ultra-wideband white noise interference, and forwarding interference. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a flowchart of the anti-interference implementation method based on Rydberg atoms according to the present invention;

[0038] Figure 2 This is a schematic diagram of the anti-interference device structure based on Rydberg atoms according to the present invention;

[0039] Figure 3 This is a schematic diagram of the energy level structure for the anti-interference implementation process based on Rydberg atoms in this invention. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0041] It should be noted that, unless otherwise specified, the various features in the embodiments of this invention can be combined with each other, all of which are within the protection scope of this invention. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than the module division in the device or the order in the flowchart. Moreover, the terms "first," "second," and "third" used in this invention do not limit the data or execution order, but only distinguish identical or similar items with essentially the same function and effect.

[0042] like Figure 2As shown, the present invention provides an anti-interference device based on Rydberg atoms, including a Cs atom gas chamber 1, a parallel plate waveguide 2, a horn 3, a power divider 4, a microwave source 5, an 852nm frequency stabilization module 6, a 509nm frequency stabilization module 7, a dichroic mirror 8, a spectrum analyzer 9, an oscilloscope 10, and a photodetector 11.

[0043] Figure 2 The core component consists of a Cs atomic gas cell 1 and a parallel plate waveguide 2, which are divided into two groups. One group of parallel plate waveguides is fed with a local oscillator signal for detection; the other group is not fed with a local oscillator signal and is used for frequency locking. The 852nm frequency stabilization module 6 provides two 852nm beams, one modulated and the other unmodulated. The two beams are injected into the Cs atomic gas cell 1, with the modulated 852nm beam entering the frequency-stabilized Cs gas cell. The 509nm frequency stabilization module 7 generates two 509nm laser beams. The 852nm and 509nm lasers collide within the Cs atomic gas cell 1, generating an EIT signal. The 852nm laser used for detection passes through the Cs gas cell 1 and then through a dichroic mirror 8, before entering a photodetector 11. The photodetector 11 converts the detected optical signal into an electrical signal. Microwave source 5 generates three microwave signals. One signal is input to parallel plate waveguide 2 via a coaxial cable as the local oscillator. The other two signals are input to horn 3 via power divider 4, illuminating Cs atom gas chamber 1. Based on the Rydberg superheterodyne principle, the local oscillator signal is mixed with the signal field signal to generate an intermediate frequency (IF) signal carrying amplitude, phase, and other information. The signal-to-noise ratio of the IF signal is observed and recorded using spectrum analyzer 9. The 509nm frequency stabilization module 7 is observed using oscilloscope 10.

[0044] like Figure 3The diagram shows the energy level structure of the Cs atom anti-interference process within the Cs atom chamber. 201 is the ground state of the Cs atom (6S¹ / ²), 203 is the excited state of the Cs atom (6P³ / ²), and 205 is the Rydberg state of the Cs atom (66D⁵ / ²). 202 is the probe light with a wavelength of 852 nm, 204 is the coupling light with a wavelength of 509 nm, and 206 is the resonance between the Rydberg state 66D⁵ / ² and a microwave signal with a frequency of 2.38 GHz. During superheterodyne signal detection, the 204 atom is excited to the Rydberg state 206 using probe light 202 and coupling light, exhibiting an EIT spectrum. Then, electromagnetically induced transparency stabilization is used to lock the coupling light 204 onto the EIT transmission peak. Next, an intrinsic microwave field (Lo) resonating with the Rydberg state 206 and a signal microwave field (SIG) detuned to the Rydberg state 206 are added. The two microwave fields mix within the atomic cluster, generating an intermediate frequency (IF) signal, which is the superheterodyne signal. The frequency and amplitude of the superheterodyne signal can be observed using a spectrum analyzer 9. At this point, an external interference signal is applied. Due to the extremely high polarizability of Rydberg atoms, they are highly sensitive to external fields. The external interference field causes the Ac.stark effect 207, shifting the energy levels and thus degrading the signal-to-noise ratio of the IF signal. To counteract the effects of energy level shift, a Cs atom gas cell 1 embedded in a parallel plate waveguide 2 without a local oscillator is used to lock the 509nm laser. This compensates for the energy level shift, improves the signal-to-noise ratio of the intermediate frequency signal, and enhances its anti-interference capability.

[0045] like Figure 1 As shown, the present invention provides a Rydberg atom receiving method resistant to electromagnetic interference, comprising the following steps:

[0046] Step 101: Place two Cs atomic gas cells 1 in a parallel plate waveguide (PPWG) 2. One gas cell is embedded in the parallel plate waveguide 2 for measurement and is fed into the local oscillator (Lo) at the coaxial cable end. The other gas cell 1 is embedded in the parallel plate waveguide 2 for laser frequency locking and is not fed into the coaxial cable end.

[0047] Step 102: The probe light 202 and the coupling light 204 are directed into the Cs atom gas cell in opposite directions to excite the Rydberg atoms;

[0048] Step 103: The interference signal and the signal field signal (SIG) are transmitted to the two Cs atom gas chambers 1 through the horn. At this time, the Rydberg atoms act as spatial mixers, and the EIT-AT spectrum will be modulated by the intermediate frequency signal generated by the mixing.

[0049] Step 104: The signal anti-interference capability can be observed by collecting the intermediate frequency signal through the photodetector 11.

[0050] Furthermore, step 101 specifically includes:

[0051] A parallel plate waveguide, 70mm long, 30mm wide, and 20mm high, was constructed using copper. One end of the waveguide was tilted at 30°, similar to a horn, and this end coupled the horn's signal field emitted in free space. A cuboid gas chamber made of high borosilicate glass was filled with Cs atoms and placed inside the waveguide. It was fixed in place using a 20mm Teflon support rod. A local oscillator signal was fed into the coaxial cable end of one waveguide; no local oscillator signal was fed into the coaxial cable end of the other gas chamber. The waveguide with the local oscillator signal was mixed with the signal field to generate a 10kHz intermediate frequency signal. The waveguide without a signal input achieved signal anti-interference by compensating for AC.stark energy shift.

[0052] Furthermore, step 102 specifically includes:

[0053] The probe light and coupling light generated by the 852nm laser and 509nm laser respectively are injected into the atomic cluster from both ends of the Cs atomic gas cell. The probe light and coupling light overlap inside the Cs cluster, and under the combined action of the probe light and coupling light, an electromagnetically induced transparent window is formed.

[0054] Furthermore, step 103 specifically includes:

[0055] Two microwave sources were used to generate two microwave signals, which were then transmitted to a speaker via a power divider. The speaker then directed both microwave signals onto a Cs atomic gas chamber. One of the microwave signals was a signal field signal, which differed from the local oscillator signal by 10 kHz and had a power of -18 dBm. The signal field and the local oscillator field were mixed in the Cs atomic gas chamber to generate an intermediate frequency (IF) signal carrying information. The other microwave signal was an interference field signal, which provided a high-frequency, high-power interference signal to test the IF signal's anti-interference capability.

[0056] The working principle of the above method is as follows: Probe light 202 and coupling light 204 are injected from both ends of the Cs atom gas cell 1 embedded in the parallel plate waveguide 2. The probe light 202 and coupling light 204 overlap inside the Cs atom 1, forming an electromagnetically induced transparent window under their combined action. A microwave source generates three microwave signals: one is fed into the parallel plate waveguide 1 as the local oscillator field, and the other two signals are input to the horn 3 through the power divider 4, illuminating the Cs gas cell 1. Of the two signals output by the horn, the one with a 10kHz phase difference from the local oscillator field serves as the signal field, and the other high-frequency, high-power signal serves as the interference field. The Rydberg atom acts as a spatial mixer, and the EIT-AT spectrum is modulated by the intermediate frequency (IF) signal generated by the mixer. The signal-to-noise ratio (SNR) of the IF signal is acquired by the spectrum analyzer 9. When there is no interference signal output, the IF signal has a good SNR; however, when an interference field is output, as the power of the interference field increases, the IF signal is submerged in the background noise of the spectrum analyzer, resulting in a very poor SNR. This is because the Rydberg states of Cs atoms have extremely high polarizability and are very sensitive to external fields. When placed in an interference field, they undergo the Ac.stark effect, resulting in energy level shifts and thus degrading the signal-to-noise ratio (SNR) of the intermediate frequency (IF) signal. To address this, another Cs atom gas cell 1, embedded in a parallel plate waveguide 2 without a local oscillator feed, is used to lock the 509nm laser. By compensating for the energy level shifts, the SNR of the IF signal is improved, thereby enhancing its anti-interference capability.

[0057] The above-disclosed embodiments are merely preferred embodiments of this application and should not be construed as limiting the scope of this application. Therefore, any equivalent variations made in accordance with the claims of this application shall still fall within the scope of this application.

Claims

1. A Rydberg atom receiver device against electromagnetic interference, characterized in that, The parallel plate waveguide atomic probe integrated with two fiber gas chambers, an 852nm frequency stabilization module, a 509nm frequency stabilization module, three microwave sources, a power divider and a horn; The three microwave sources are respectively used for generating a local field signal, a signal field signal and an interference field signal; The parallel plate waveguide atomic probe integrated with two fiber gas chambers comprises a first parallel plate waveguide atomic probe and a second parallel plate waveguide atomic probe; The first parallel plate waveguide atomic probe and the second parallel plate waveguide atomic probe respectively comprise two oppositely arranged fiber tail fibers connected with alkali metal atomic gas chambers, and further comprise a parallel plate waveguide for embedding the alkali metal atomic gas chambers, which is made of red copper and has an outwardly inclined one end forming a wide port; The power divider is used for inputting the signal field signal and the interference field signal into the horn, and the horn is used for coupling the signal field signal and the interference field signal into the wide port; The 852nm frequency stabilization module is used for providing two 852nm lasers as probe light; The 509nm frequency stabilization module is used for providing two 509nm lasers as coupling light; One of the 852nm lasers of the 852nm frequency stabilization module and one of the 509nm lasers of the 509nm frequency stabilization module are respectively incident on the first parallel plate waveguide atomic probe through two oppositely arranged fiber tail fibers to excite Rydberg atoms and lock the 852nm laser and the 509nm laser; The other 852nm laser of the 852nm frequency stabilization module and the other 509nm laser of the 509nm frequency stabilization module are incident on the second parallel plate waveguide atomic probe without signal feed to lock the 509nm laser; Two alkali metal atomic gas chambers are respectively embedded in the two parallel plate waveguide atomic probes, wherein the first alkali metal atomic gas chamber in the first parallel plate waveguide atomic probe receives the local field signal, the signal field signal and the interference field signal, mixes the local field signal and the signal field signal to generate an intermediate frequency signal, and the second alkali metal atomic gas chamber in the second parallel plate waveguide atomic probe receives the signal field signal and the interference field signal to realize signal anti-interference by compensating for the AC Stark shift.

2. The apparatus of claim 1, wherein, The alkali metal atomic gas chamber is a cuboid gas chamber made of high borosilicon, filled with Cs atoms, and a support rod made of Teflon material is fixed in the parallel plate waveguide.

3. The apparatus of claim 2, wherein, Further comprising a photodetector, an oscilloscope and a spectrum analyzer; The photodetector is used for detecting the intermediate frequency signal; The oscilloscope is used for observing the frequency locking of the 509nm frequency stabilization module; The spectrum analyzer is used for observing and recording the signal-to-noise ratio of the intermediate frequency signal.

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