Fast neutron wireless communication method

Abstract

The invention discloses a fast neutron wireless communication method. The method comprises the following steps: S1, an information coding module converts to-be-transmitted information into pulse digital coding information consisting of high and low levels according to an information coding protocol; s2, a fast neutron pulse module acts on a fast neutron generation module according to the pulse digital coding information to form a pulse neutron radiation signal sequence corresponding to the pulse digital coding information; s3, a fast neutron detection module detects the pulse neutron radiation signal sequence to obtain pulse neutron radiation signal sequence information; and S4, the neutron pulse decoding module converts the pulse neutron radiation signal sequence information into to-be-transmitted information according to an information coding protocol. According to the invention, near-field wireless communication is carried out at two ends of a metal object or two ends of an electromagnetic shielding building and other scenes in which traditional wireless communication based on electromagnetic wave signals cannot be used or is limited by using the characteristic that fast neutrons have strong penetrating power to the metal object, the electromagnetic shielding building and the like.

Description

Technical Field

[0001] The present application relates to the fields of nuclear technology and communication, and in particular to a fast neutron wireless communication method. Background Art

[0002] Traditional wireless communication technologies mainly use electromagnetic waves as the wireless communication medium for long-distance information transmission. As a common communication technology, electromagnetic wave wireless communication technology has been widely applied in various fields of society, providing great convenience for people's production and life. However, in some places with special requirements for electromagnetic shielding, electromagnetic interference, electromagnetic leakage or intrusion, etc., such as the shielding effect of the nuclear island building in a nuclear power plant is very strong, and electromagnetic wave wireless communication signals cannot be received in places with electromagnetic shielding inside the nuclear island. At the same time, due to a large number of electrical, control, instrumentation and other devices arranged inside the nuclear island, these devices are usually very sensitive to electromagnetic interference problems and information security transmission problems, and the maximum transmission power of wireless communication devices is limited, making the wireless communication technology based on electromagnetic wave transmission unable to be used or limited in use in these special places.

[0003] Fast neutron radiation rays are uncharged, and their interaction characteristics during propagation in free space are in sharp contrast to those of electromagnetic radiation. They have strong penetrability for high-Z materials, such as metal materials, and can enter places that electromagnetic waves cannot penetrate. Theoretically, fast neutrons can be used as a near-field wireless communication transmission medium and are a potential wireless communication means. However, due to the radiation characteristics of fast neutrons, and the generation of fast neutrons is usually accompanied by complex gamma-ray components, their safe use is strictly regulated and restricted. However, with the development of related technologies such as neutron generators and fast neutron shielding and collimation, the application of fast neutrons has entered a large number of industrial non-destructive testing and security inspection fields.

[0004] In existing applications, fast neutrons are usually provided by isotope neutron sources (such as californium-252 neutron sources) or neutron generators. Pulsed neutrons are usually realized by pulsing the neutrons generated by neutron generators, and the repetition frequency generally does not exceed 20 kHz. The pulsed neutrons are repetitive pulses with exactly the same pulse width and time interval, but there is no generation and application of other forms of pulsed neutrons such as specific coding time sequences or random frequencies. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a fast neutron wireless communication method. The present invention uses deuterium-deuterium / deuterium-tritium fast neutron radiation rays with an energy in the MeV range as the near-field wireless communication medium, and utilizes the characteristics of strong penetrability of deuterium-deuterium / deuterium-tritium fast neutrons for metal objects, electromagnetic shielding buildings, etc., to perform near-field wireless communication in scenarios where traditional wireless communication based on electromagnetic wave signals cannot be used or is limited in use, such as at both ends of metal objects or both ends of electromagnetic shielding buildings.

[0006] The present invention provides a fast neutron wireless communication method, which is characterized by comprising the following steps:

[0007] S1, an information encoding module converts the information to be transmitted into pulse digital encoding information composed of high and low levels according to an information encoding protocol, wherein, "0" represents the low level of the pulse digital encoding, and "1" represents the high level of the pulse digital encoding;

[0008] S2, a fast neutron pulsing module acts on a fast neutron generation module according to the pulse digital encoding information to form a pulse neutron radiation signal sequence corresponding to the pulse digital encoding information;

[0009] S3, a fast neutron detection module detects the pulse neutron radiation signal sequence to obtain pulse neutron radiation signal sequence information;

[0010] S4, a neutron pulse decoding module converts the pulse neutron radiation signal sequence information into the information to be transmitted according to the information encoding protocol.

[0011] Further, in step S1, the information encoding protocol is a standard ASCII code, Unicode code or a user-defined data encoding protocol, which is represented by a string of "0" and "1" digits conforming to the corresponding encoding standard, and its modulation method can adopt pulse width modulation or pulse frequency modulation.

[0012] Further, in step S2, the fast neutron pulsing module realizes the pulsing of fast neutrons by other physical means such as the blocking and opening of a collimating shield.

[0013] Further, in step S2, the physical blocking method is a high-voltage shutter.

[0014] Further, in step S2, the fast neutron generation module is an accelerator neutron source for generating fast neutrons, such as a deuterium-deuterium / deuterium-tritium neutron generator or a deuterium-tritium neutron generator with associated alpha particle tagging.

[0015] Further, in step S3, the fast neutron detection module adopts a dual-mode neutron detector that is sensitive to fast and thermal neutrons and has pulse shape discrimination characteristics. The detector material serves as both a neutron detection sensitive material and a neutron moderation material, and contains elements with a large thermal neutron reaction cross section to realize the simultaneous dual-mode measurement of fast and thermal neutrons, such as a plastic scintillator detector doped with lithium-6 and having pulse shape discrimination characteristics, which directly measures the fast neutron pulse.

[0016] Further, in step S3, the fast neutron detection module is a plastic scintillator detector doped with lithium-6.

[0017] Further, in step S5, only a fast neutron pulsing module is provided at one end and only a fast neutron detection module is provided at the other end to achieve unidirectional wireless communication; or the fast neutron pulsing module and the fast neutron detection module are paired and arranged at both ends to achieve bidirectional wireless communication.

[0018] Advantages of the present invention:

[0019] It is applicable to near-field wireless communication in scenarios where traditional electromagnetic transmission is infeasible or subject to inherent limitations, and can be used as a supplement to traditional wireless communication technologies. In cases where safety requirements such as electromagnetic shielding, electromagnetic interference, leakage, and intrusion of devices, facilities, and buildings are crucial for their structural integrity, the fast neutron wireless communication technology of the present invention can minimize the penetration times of communication cables passing through these metal structures, thus effectively avoiding complex problems such as traditional cable laying. The present invention uses fast neutron radiation rays with an energy level in the MeV range as the wireless communication medium, which has higher penetrability and can achieve short-range wireless transmission of information inside and outside a sealed container or enclosed space formed by thick metal materials, etc. Description of the drawings

[0020] Figure 1 It is a schematic flow diagram of the fast neutron wireless communication method of the present invention;

[0021] Figure 2 It is a schematic flow diagram of Embodiment 1 of the fast neutron wireless communication method of the present invention;

[0022] Figure 3 It is a schematic diagram of the pulsed neutron radiation signal sequence in Embodiment 1 of the fast neutron wireless communication method of the present invention;

[0023] Figure 4 It is a schematic flow diagram of Embodiment 2 of the fast neutron wireless communication method of the present invention;

[0024] Figure 5 It is a schematic diagram of the high-level neutron signal in Embodiment 2 of the fast neutron wireless communication method of the present invention;

[0025] Figure 6 It is a schematic diagram of the low-level neutron signal in Embodiment 2 of the fast neutron wireless communication method of the present invention;

[0026] In the figure, 1. Information encoding module, 2. Fast neutron pulsing module, 3. Fast neutron generation module, 4. Fast neutron detection module, 5. Neutron pulse decoding module. Detailed implementation manners

[0027] The technical solution of the present invention will be described below with reference to the accompanying drawings.

[0028] The present invention provides a fast neutron wireless communication method, as Figure 1 shown, which is characterized by including the following steps:

[0029] S1. The information encoding module 1 converts the information to be transmitted into pulse digital encoding information composed of high and low levels according to the information encoding protocol. Among them, "0" represents the low level of the pulse digital encoding, and "1" represents the high level of the pulse digital encoding. Pulse width modulation can be used, and a sub-sequence of pulses in a specific timing is used as the digital information carrier for wireless communication. The pulse neutron sequence has a neutron signal (pulse mode or current mode) within a certain time width as the binary digit "1", and no neutron signal within a certain time width in the pulse neutron sequence as the binary digit "0". The presence or absence of pulse neutrons within this time width is used as the basic unit of digital encoding. Or pulse frequency modulation can be used, with pulses of a specific frequency as the binary digit "1" and pulse signals of another specific frequency as the binary digit "0", and the information is modulated onto the neutron signal through frequency modulation.

[0030] S2. The fast neutron pulsing module 2 acts on the fast neutron generation module 3 according to the pulse digital encoding information to form a sequence of pulse neutron radiation signals corresponding to the pulse digital encoding information.

[0031] S3. The fast neutron detection module 4 detects the sequence of pulse neutron radiation signals to obtain the information of the sequence of pulse neutron radiation signals.

[0032] S4. The neutron pulse decoding module 5 converts the information of the sequence of pulse neutron radiation signals into the information to be transmitted according to the information encoding protocol. By arranging the pulse neutron generation end and the pulse neutron detection end in pairs at both ends, two-way wireless communication at both ends can be realized.

[0033] Further, in step S1, the information encoding protocol is the standard ASCII code, Unicode code or a user-defined data encoding protocol, which is represented by a set of "0" and "1" digits that conform to the corresponding encoding standard, and its modulation method can adopt pulse width modulation or pulse frequency modulation.

[0034] Further, in step S2, the fast neutron pulsing module 2 realizes the pulsing of fast neutrons by physically blocking the fast neutron generation module 3. For example, the neutron source is placed in a shielding body, and a collimation hole for outputting neutrons is reserved on the shielding body to prevent fast neutrons from being emitted in other directions to generate scattered neutron background. The collimation hole needs to be large enough to ensure that the neutron detector can obtain sufficient statistics within one fast neutron pulse period. By physically "blocking" and "unblocking" the collimation hole, the "off" and "on" of neutron output are realized to form neutron pulses. By controlling the time width of "blocking" and "unblocking", the time width of pulse neutrons is controlled, and by controlling the repetition sequence of "blocking" and "unblocking", the time sequence of pulse neutrons is controlled.

[0035] By pulse-controlling the working parameters of the neutron beam device (such as high voltage, current, etc.), neutron pulses are realized by ion source pulses, beam extraction pulses, or target pressure pulses. By controlling the working parameters of the neutron generator (such as high voltage, current, etc.), the information to be encoded is modulated on the pulsed neutron signal.

[0036] Furthermore, in step S2, the physical blocking method is a high-voltage shutter.

[0037] Furthermore, in step S2, the fast neutron generating module is an accelerator neutron source that generates fast neutrons, such as a deuterium-deuterium / deuterium-tritium neutron generator or a deuterium-tritium neutron generator with accompanying alpha particle markers.

[0038] Furthermore, the fast neutron source is a radioisotope neutron source, such as a californium-252 neutron source, or a deuterium-deuterium / deuterium-tritium neutron generator or a deuterium-tritium neutron generator with an accompanying alpha particle marker. The neutron ray device is placed in a shielding body, and a collimation hole for outputting neutrons is reserved on the shielding body to prevent fast neutrons from being emitted in other directions to generate a scattered neutron background. According to the actual situation of the fast neutron transmission path through the medium, the fast neutron detector is placed naked, or placed in a shielding body with a hole left in the direction of fast neutron transmission, or placed in an absorber that can absorb slow neutrons below a certain energy threshold, and the fast neutron pulse is directly measured, the fast neutron pulse waveform or count is recorded, and the fast neutron pulse sequence is directly obtained.

[0039] Furthermore, in step S3, the fast neutron detection module uses a dual-mode neutron detector with pulse shape discrimination characteristics that is sensitive to fast and thermal neutrons. The detector material is used as both a neutron detection sensitive material and a neutron moderator material, and contains elements with a large reaction cross section with thermal neutrons, so as to achieve dual-mode simultaneous measurement of fast and thermal neutrons, such as a lithium-6-doped plastic scintillator detector with pulse shape discrimination characteristics, which directly measures fast neutron pulses.

[0040] Furthermore, in step S3, the fast neutron detection module is a lithium-6 doped plastic scintillator detector.

[0041] Furthermore, in step S5, only a fast neutron pulse module is provided at one end, and only a fast neutron detection module is provided at the other end, so as to realize one-way wireless communication; or a fast neutron pulse module and a fast neutron detection module are arranged in pairs at both ends, so as to realize two-way wireless communication. The present invention relates to the design of auxiliary devices such as shielding, collimation and moderation of fast neutrons, and the design of parameters such as fast neutron intensity, time width and time interval can be determined by calculation and simulation of neutron transport Monte Carlo program (such as MCNP program).

[0042] Example 1

[0043] Figure 2Shows a specific implementation of the fast neutron wireless communication technology of the present invention. The basic process of fast neutron wireless communication mainly includes: information encoding at the information sending end, information transmission, information reception at the information receiving end, and information decoding.

[0044] Taking the most basic information to be transmitted "OK" as an example, the information pulse encoding module 1 converts the to-be-transmitted "OK" into two 7-bit binary strings according to the standard ASCII protocol. "O" corresponds to "1101111", and "K" corresponds to "1101011". Therefore, during the information encoding process, "OK" is represented by the binary string "11011111101011" this group of codes, completing the information encoding process.

[0045] The fast neutron generation module 3 is selected as a deuterium-deuterium / deuterium-tritium neutron generator or a deuterium-tritium neutron generator with associated alpha particle calibration, and is composed of a Penning ion source, a deuterium storage, a beam extraction system, a tritium target, a vacuum and pressure-resistant cavity, high voltage and control, etc. The neutron output of the neutron generator is not less than 1×10 8 n / s. The fast neutron pulsing module 2 is realized by controlling the high voltage device and circuit of the Penning ion source discharge high voltage power supply [ON] / [OFF] state. The [ON] / [OFF] state of the Penning ion source discharge high voltage power supply is set according to the logic of "11011111101011" by its control circuit, where "1" is the power supply [ON] state and "0" is the [OFF] state. Convert the ASCII string encoded information "11011111101011" representing the to-be-transmitted information "OK" into the [ON] / [OFF] state of the high voltage pulse of the Penning ion source that controls the generation of fast neutron pulses. The high voltage power supply switch that controls the Penning ion source discharge discharges in pulses according to the [ON] / [OFF] state of "11011111101011", generating a pulsed beam current with corresponding time sequence. After being extracted and hitting the target, pulsed neutrons with corresponding time sequence are generated, thereby emitting a corresponding pulsed neutron sequence, as Figure 3 shown, completing the information transmission process at the information sending end.

[0046] The fast neutron detection module 4 is composed of a plastic scintillation detector doped with lithium-6 with pulse shape discrimination characteristics and data acquisition and analysis. The liquid scintillation detection is a 3-inch Cs2LiYCl6:Ce (CLYC) plastic scintillator coupled with a photomultiplier tube. The anode output signal of the photomultiplier tube is connected to the neutron / gamma discrimination circuit to perform pulse shape discrimination on the neutron / gamma radiation signal. The pulsed signal after completing the pulse shape discrimination is sent to the counter to obtain the pulsed neutron time sequence information. The relevant information is transmitted to the data analysis computer through the network cable, and software is compiled to analyze, store, and display the data, etc., detecting the pulsed neutron sequence emitted by the neutron generator with high fidelity, completing the information reception process at the information receiving end.

[0047] On the data analysis computer, the neutron pulse decoding module 5 first converts the received pulsed neutron sequence into a binary string "11011111101011", and then decodes this string according to the standard ASCII protocol. The first 7 characters correspond to the English letter "O", and the last 7 characters correspond to the English letter "K", converting it into the corresponding information to be transmitted "OK", thus completing the information decoding process.

[0048] Embodiment 2

[0049] Figure 4 Another specific implementation of the fast neutron wireless communication technology of the present invention is shown. Using frequency modulation, taking the most basic information to be transmitted "OK" as an example, the signal encoding process is the same as that in Embodiment 1, and the encoded signal of "OK" is "11011111101011". The information encoding module 1 encodes the information "OK" and transmits it to the fast neutron pulsing module 2.

[0050] When modulating the neutron signal transmission, it is set that when the neutron generator operates at a frequency of 10 kHz, it is "1", and when it operates at a frequency of 2 kHz, it is "0".

[0051] The fast neutron generation module 3 is selected as a neutron generator, and its composition structure is the same as that in Embodiment 1. The fast neutron generation module 3 outputs pulsed neutrons with frequencies of 2 kHz and 10 kHz, and the output pulse width is 50 us. The fast neutron pulsing module 2 realizes the conversion of the output neutron frequency by controlling the output frequency of the Penning ion source discharge high-voltage power supply. The pulse width of a single signal is 1 ms. For example, the neutron signal of "1" is as Figure 5 shown, and the neutron signal of "0" is as Figure 6 shown.

[0052] Convert the ASCII string encoded information "11011111101011" representing the information to be transmitted "OK" into a high-voltage pulse signal of the Penning ion source that controls the generation of fast neutrons. Control the pulse frequency of the Penning ion source discharge to perform pulsed discharge according to the state of "11011111101011", generate a pulsed beam current with the corresponding frequency, and after being led out and hitting the target, generate pulsed neutrons with the corresponding time sequence, thereby emitting the corresponding pulsed neutron sequence and completing the information emission process at the information sending end.

[0053] The fast neutron detection module 4 consists of a plastic scintillation detector doped with lithium-6 with pulse shape discrimination characteristics and data acquisition and analysis. The liquid scintillation detection uses a 3-inch Cs2LiYCl6:Ce (CLYC) plastic scintillator coupled with a photomultiplier tube. The anode output signal of the photomultiplier tube is connected to the neutron / gamma discrimination circuit to perform pulse shape discrimination on the neutron / gamma radiation signal. The pulse signal after pulse shape discrimination is sent to a counter to obtain the pulse neutron timing information. The relevant information is transmitted to the data analysis computer through a network cable, and software is compiled to analyze, store, and display the data, etc. The pulsed neutron sequence emitted by the portable neutron generator is detected with high fidelity, and the information receiving process at the information receiving end is completed.

[0054] On the data analysis computer, the neutron pulse decoding module 5 first converts the received pulsed neutron sequence into a binary string "11011111101011", and then decodes this string according to the standard ASCII protocol. The first 7 characters correspond to the English letter "O", and the last 7 characters correspond to the English letter "K", and it is converted into the corresponding information to be transmitted "OK", completing the information decoding process.

[0055] The present invention has been described in detail above in combination with specific embodiments and exemplary examples. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments; the above description should not be construed as a limitation of the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent replacements, modifications, or improvements can be made to the technical solutions and their implementation manners of the present invention, and these all fall within the scope of the present invention; the protection scope of the present invention is subject to the appended claims.

Claims

1. A fast neutron wireless communication method, characterized in that: The following steps are involved: S1, the information encoding module (1) converts the information to be transmitted into pulse digital encoding information composed of "0" and "1" according to the information encoding protocol; S2, the fast neutron pulsing module (2) acts on the fast neutron generating module (3) according to the pulse digital coding information to form a pulse neutron radiation signal sequence corresponding to the pulse digital coding information; S3, the fast neutron detection module (4) detects the pulse neutron radiation signal sequence to obtain pulse neutron radiation signal sequence information; S4, the neutron pulse decoding module (5) converts the pulse neutron radiation signal sequence information into information to be transmitted according to the information encoding protocol.

2. A fast neutron wireless communication method according to claim 1, characterized in that: In step S1, the information encoding protocol is a standard ASCII code, Unicode code or a user-defined data encoding protocol.

3. A fast neutron wireless communication method according to claim 1, characterized in that: In step S2, the fast neutron pulsing module (2) realizes the pulsing of fast neutrons by blocking and opening the collimating shield.

4. A fast neutron wireless communication method according to claim 3, characterized in that: In step S2, the physical blocking method is a high-voltage shutter.

5. A fast neutron wireless communication method according to claim 1, characterized in that: In step S2, the fast neutron generation module (3) is an accelerator neutron source that generates fast neutrons.

6. A fast neutron wireless communication method according to claim 5, characterized in that: The accelerator neutron source is a deuterium-deuterium / deuterium-tritium neutron generator or a deuterium-tritium neutron generator with accompanying alpha particle labels.

7. A fast neutron wireless communication method according to claim 1, characterized in that: In step S3, the fast neutron detection module (4) uses a dual-mode neutron detector that is sensitive to fast and thermal neutrons and has pulse shape discrimination characteristics.

8. A fast neutron wireless communication method according to claim 7, characterized in that: In step S3, the fast neutron detection module (4) is a lithium-doped-6 plastic scintillator detector.

9. A fast neutron wireless communication method according to claim 7, characterized in that: In step S5, only a fast neutron pulsing module is set at one end of the communication, and only a fast neutron detection module is set at the other end to perform one-way wireless communication; or a fast neutron pulsing module and a fast neutron detection module are arranged in pairs at both ends of the communication to perform two-way wireless communication.

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