WO2020000870A1

WO2020000870A1 - Electromagnetic radiation detecting system and detecting method

Info

Publication number: WO2020000870A1
Application number: PCT/CN2018/115728
Authority: WO
Inventors: 贾成艳; 王荣; 祁春超
Original assignee: 深圳市华讯方舟太赫兹科技有限公司; 华讯方舟科技有限公司
Priority date: 2018-06-26
Filing date: 2018-11-15
Publication date: 2020-01-02
Also published as: CN108761215A

Abstract

An electromagnetic radiation detecting system and detecting method, the electromagnetic radiation detecting system comprising: a receiving antenna (101), a spectrum analyzer (102) and a cable assembly (103); the receiving antenna (101) is connected to the spectrum analyzer (102) by means of the cable assembly (103); the receiving antenna (101) is used for receiving an electromagnetic radiation signal in a preset area when a security check device is operating; the spectrum analyzer (102) is used for analyzing the electromagnetic radiation signal so as to obtain signal parameters of the electromagnetic radiation signal and calculate the electromagnetic radiation power density of the security check device according to the signal parameters and the parameters of the receiving antenna (101). The accuracy of electromagnetic radiation detection by the security check device may be improved by means of the described method.

Description

Electromagnetic radiation detection system and detection method

[Technical Field]

The present application relates to the technical field of security inspection equipment, and in particular, to an electromagnetic radiation detection system and a detection method.

【Background technique】

Existing electromagnetic radiation detection equipment uses a sensor probe to sense electromagnetic signals in the environment, and obtains the electromagnetic radiation power density in the environment after signal processing. However, since the millimeter wave or terahertz wave radiation emitted by the millimeter wave human body security inspection device is very small, the accuracy of the existing electromagnetic radiation detection equipment is not high enough to accurately measure the electromagnetic radiation of the millimeter wave human body security inspection device.

[Summary of the Invention]

The present application mainly provides an electromagnetic radiation detection system and detection method, which can improve the electromagnetic radiation detection accuracy of a millimeter wave human body security inspection instrument.

In order to solve the above technical problems, a technical solution adopted in the present application is to provide an electromagnetic radiation detection method, which is applied to an electromagnetic radiation detection system. The electromagnetic radiation detection system includes a receiving antenna, a spectrum analyzer, a vector network analyzer, and a cable. The receiving antenna is connected to the spectrum analyzer through a cable assembly; the vector network analyzer is connected to the cable assembly; the method includes: using the receiving antenna to receive the electromagnetic radiation signal of a preset area when the security detector works; using the spectrum analyzer to analyze the electromagnetic radiation signal And obtain the signal parameters of the electromagnetic radiation signal; use the vector network analyzer to obtain the insertion loss of the cable assembly; use the insertion loss to compensate the signal parameters of the electromagnetic radiation signal; calculate the security check with the compensated signal parameters and the parameters of the receiving antenna as known parameters The electromagnetic radiation power density of the instrument; wherein the signal parameters include the time domain signal peak of the electromagnetic radiation signal at a preset frequency point.

In order to solve the above technical problem, another technical solution adopted in the present application is to provide an electromagnetic radiation detection system including: a receiving antenna, a spectrum analyzer, and a cable assembly; the receiving antenna is connected to the spectrum analyzer through a cable assembly; Receive the electromagnetic radiation signal in the preset area when the security detector works; the spectrum analyzer is used to analyze the signal parameters of the electromagnetic radiation signal to calculate the electromagnetic radiation power density of the security detector according to the signal parameters and the parameters of the receiving antenna.

In order to solve the above technical problem, another technical solution adopted in the present application is to provide an electromagnetic radiation detection method, which is applied to the electromagnetic radiation detection system as described above. The method includes: receiving electromagnetic radiation in a preset area when the security checker works Signal; analyzing the signal parameters of the electromagnetic radiation signal; calculating the electromagnetic radiation power density of the security checker with the signal parameters and the parameters of the receiving antenna as known parameters.

The beneficial effect of the present application is that, unlike in the prior art, in some embodiments of the present application, the electromagnetic radiation detection system uses a receiving antenna to receive electromagnetic radiation signals in a preset area during the operation of the security detector, and then uses a spectrum analyzer to analyze electromagnetic The time-domain signal parameters of the radiated signal are used to calculate the electromagnetic radiation power density of the security detector based on the time-domain signal parameters and the parameters of the receiving antenna. Due to the higher accuracy of the spectrum analyzer, the signal parameters of the electromagnetic radiation signals with lower power can be obtained. Finally, the accuracy of the calculated electromagnetic radiation power density is improved.

[Brief Description of the Drawings]

1 is a schematic structural diagram of a first embodiment of an electromagnetic radiation detection system of the present application;

2 is a schematic diagram of an application scenario of the first embodiment of the electromagnetic radiation detection system of the present application;

3 is a schematic structural diagram of a second embodiment of an electromagnetic radiation detection system of the present application;

4 is a schematic diagram of an application scenario of a second embodiment of an electromagnetic radiation detection system of the present application;

5 is a schematic diagram of a scenario in which a spectrum analyzer is removed in a second embodiment of the electromagnetic radiation detection system of the present application, and a vector network analyzer is directly connected to detect the insertion loss of a cable component;

6 is a schematic flowchart of an embodiment of an electromagnetic radiation detection method of the present application;

FIG. 7 is a detailed flowchart of step S16 in FIG. 6; FIG.

FIG. 8 is a schematic diagram of a specific process after step S14 in FIG. 6.

【detailed description】

In the following, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

As shown in FIG. 1, in the first embodiment of the electromagnetic radiation detection system of the present application, the electromagnetic radiation detection system 10 includes a receiving antenna 101, a spectrum analyzer 102, and a cable assembly 103. The receiving antenna 101 is connected to the spectrum analyzer 102 through a cable assembly 103.

The receiving antenna 101 is used for receiving electromagnetic radiation signals in a preset area during the operation of the security checker. The spectrum analyzer 102 is used to analyze the signal parameters of the electromagnetic radiation signal, so as to calculate the electromagnetic radiation power density of the security detector according to the signal parameters and the parameters of the receiving antenna 101.

Optionally, as shown in FIG. 2, the electromagnetic radiation detection system 10 in this embodiment may further include a human body security detector 300.

Among them, the security checker 300 is a millimeter wave / terahertz human security checker, which emits millimeter wave / terahertz waves to the human body when it is working. The existing security checkers on the market generally have a small emission power and reach the power density of the surface of the object It is far lower than the electromagnetic radiation control standard of 2W / m ^{2. The} accuracy of using ordinary electromagnetic radiation detection equipment is too low, and the detected electromagnetic radiation is not accurate enough. Therefore, in this embodiment, a high-precision spectrum analyzer is used for detection, which can detect Smaller power signals, thus improving detection accuracy.

The preset area is an area where a human body stands in the security checker 300. For example, when the security checker 300 has two layers of inner and outer glass surrounding the human detection area, the antenna mouth of the receiving antenna 101 and the inner glass of the security checker 300 are first preset. The area at a distance and a second preset distance from the position of the sole of the foot when the human body at the bottom of the security inspection device 300 stands is the preset area. The first preset distance and the second preset distance are set according to actual detection requirements. For example, the first preset distance may be one of 30cm, 40cm, and 50cm, and the second preset distance may be 50cm, One of 100cm and 135cm.

The receiving antenna 101 is an antenna that can receive millimeter waves / terahertz waves, such as a horn antenna or an array antenna with a working frequency band of 26 GHz to 40 GHz. The parameter gain of the receiving antenna 101 can be set according to detection requirements, such as 10dB, 15dB, 20dB or 25dB, etc., this gain can be set according to different detection requirements, such as the use of antennas with different gains at different detection frequencies, which is not specifically limited here.

The cable assembly 103 is a cable that transmits electrical signals, such as a coaxial cable. The length of the cable assembly 103 can be adjusted according to different detection products or site layouts, and its model can also be selected according to the requirements of the detection frequency band, which is not specifically limited here.

The spectrum analyzer 102 is an instrument for studying the spectrum structure of an electrical signal, such as a scanning-tuned spectrum analyzer. In this embodiment, the spectrum analyzer is an instrument that can analyze signals in the frequency band corresponding to the millimeter wave or the terahertz frequency band, and its specific parameter configuration It can be set according to actual detection requirements, and is not specifically limited here.

Specifically, in an application example, as shown in FIG. 2, when detecting the electromagnetic radiation of the human body security device 300, the receiving antenna 101 (such as a horn antenna with a standard gain) may be set in a preset inside the human body security device 300. Area A, where the preset area A may be an area that is 30 cm, 40 cm, or 50 cm away from the antenna mouth and the glass in the security inspection device 300, and the distance between the bottom of the receiving antenna 101 and the foot position when the human body stands is 50 cm, 100 cm, or 135 cm. When the human body security device 300 is turned on for scanning, the transmitting antenna of the human body security device 300 emits electromagnetic waves (millimeter wave / terahertz wave). The receiving antenna 101 provided in the preset area A can receive the electromagnetic waves and convert them into electromagnetic waves. After radiating the signal, the transmission through the cable assembly 103 (such as a 2.92mm coaxial cable with a length of 1.5m) can be received by the spectrum analyzer 102. The spectrum analyzer 102 analyzes the received electromagnetic radiation signal and acquires the electromagnetic Signal parameters of the radiated signal. For example, when the spectrum analyzer 102 is set to the time domain mode, its bandwidth at a single frequency point is 0Hz, the intermediate frequency bandwidth can be 8MHz, and the scan time can be set to 5s. Then the spectrum analyzer 102 can analyze and display the electromagnetic The time-domain signal peak of the radiated signal at different frequency points, that is, the power value of the electromagnetic radiation signal at each frequency point, for example, at multiple frequencies such as 29.12GHz, 31.12GHz, 33.12GHz, 35.12GHz, 37.12GHz, and 38.12GHz The peak time domain signal at the point. According to the peak value of the time domain signal and the parameters (such as gain) of the receiving antenna 101, the following formula (1) can be used to calculate the electromagnetic radiation power density of the human security device 300:

Among them, q is the unit electromagnetic radiation power density, P is the power value of the electromagnetic radiation signal received by the receiving antenna 101, and A is the effective detection area of the receiving antenna 101.

The effective detection area A of the receiving antenna 101 can be calculated by using the following formula (2):

Among them, A is the effective detection area of the receiving antenna 101, λ is the wavelength corresponding to the frequency at which the power value of the electromagnetic radiation signal is located, and G is the gain of the receiving antenna 101 at the current frequency.

Optionally, as shown in FIG. 2, the electromagnetic radiation detection system 20 may further include a processing device 105 connected to the spectrum analyzer 102 to acquire signal parameters of the electromagnetic radiation signal and calculate the electromagnetic radiation thereof. Power density.

The processing device 105 is a device having communication and computing functions, such as a mobile phone, a computer, a tablet, a server, or the like, and may also be a part of an element integrated with the above device, such as a signal processing chip.

Specifically, in the above application example, the processing device 105 may obtain the time-domain signal peak value of the electromagnetic radiation signal analyzed by the spectrum analyzer 102, and then use the formulas (1) and (2) to calculate the unit of the electromagnetic radiation signal. Power density of electromagnetic radiation.

Through the above detection process, the unit electromagnetic radiation power density of the electromagnetic radiation signals generated by the human security device can be analyzed, and because the spectrum analyzer has higher accuracy, it can analyze the electromagnetic radiation signals with lower power and obtain its signal parameters. , And finally improve the accuracy of the unit electromagnetic radiation power density obtained by detection.

In other embodiments, in order to further improve the detection accuracy, the electromagnetic radiation detection system can also compensate the insertion loss of the cable assembly to the power value of the electromagnetic radiation signal.

Specifically, as shown in FIG. 3, in the second embodiment of the electromagnetic radiation detection system of the present application, the electromagnetic radiation detection system 20 includes a receiving antenna 101, a spectrum analyzer 102, a cable assembly 103, and a vector network analyzer 104. The receiving antenna 101 is connected to the spectrum analyzer 102 through a cable assembly 103, and the vector network analyzer 104 is connected to the cable assembly 103.

The receiving antenna 101 is used for receiving electromagnetic radiation signals in a preset area during the operation of the security checker. The spectrum analyzer 102 is configured to obtain signal parameters of the electromagnetic radiation signal.

The vector network analyzer 104 is used to obtain the insertion loss of the cable assembly 103, to use the insertion loss to compensate the signal parameters of the electromagnetic radiation signal, and to calculate the electromagnetic radiation power of the security checker according to the compensated signal parameters and the parameters of the receiving antenna 101 density.

Optionally, the electromagnetic radiation detection system 20 in this embodiment may further include a human body security detector 300. The human body security checker 300 is a millimeter wave / terahertz human body security checker, which emits a millimeter wave / terahertz wave to a human body during operation.

Specifically, in an application example, as shown in FIG. 4, when detecting electromagnetic radiation of the human body security device 300, the receiving antenna 101 (such as a horn antenna with a standard gain) may be set in a preset inside the human body security device 300. Area, when the human security device 300 is turned on for scanning, the transmitting antenna of the human security device 300 emits electromagnetic waves (millimeter wave / terahertz wave), and the receiving antenna 101 provided in the preset area can receive the electromagnetic wave and convert it into After the electromagnetic radiation signal is transmitted through the cable assembly 103, it can be received by the spectrum analyzer 102. The spectrum analyzer 102 analyzes the received electromagnetic radiation signal and obtains the signal parameters of the electromagnetic radiation signal, such as multiple detection frequency points Time domain signal peak. Then, the vector network analyzer 104 can test the detected cable assembly 103 to obtain the insertion loss corresponding to each of a plurality of detected frequency points. According to the insertion loss, the time-domain signal peak value of the electromagnetic radiation signal can be compensated, and the compensated time-domain signal peak value can be obtained. Furthermore, according to the compensated time-domain signal peak value and parameters (such as gain) of the receiving antenna 101, the same Using the above formulas (1) and (2), the unit electromagnetic radiation power density of the electromagnetic radiation signal can be calculated. Wherein, to detect the insertion loss of the cable assembly 103, only the vector network analyzer 104 is required. At this time, the spectrum analyzer 102 is not working, or as shown in FIG. 5, the spectrum analyzer 102 can be directly removed. Detection is performed using a vector network analyzer 104.

Optionally, as shown in FIG. 4, the electromagnetic radiation detection system 20 may further include: a processing device 106, which is connected to a spectrum analyzer 102 and a vector network analyzer 104 respectively, for acquiring signals of the electromagnetic radiation signal Parameters and insertion loss, use the insertion loss to compensate the signal parameter, and calculate the electromagnetic radiation power density using the compensated signal parameter.

The processing device 106 is a device having communication and computing functions, such as a mobile phone, a computer, a tablet, a server, or the like, or may be a component integrated with the above device, such as a signal processing chip.

Specifically, in the above application example, the processing device 106 may obtain the time-domain signal peak of the electromagnetic radiation signal analyzed by the spectrum analyzer 102 and the insertion loss of the cable assembly 103 obtained by the vector network analyzer 104, and then The insertion loss is used to compensate the time domain signal peak, and after the compensated time domain signal peak is obtained, the unit electromagnetic radiation power density of the electromagnetic radiation signal is calculated by using the formulas (1) and (2) above.

Through the above detection process, due to the high accuracy of the spectrum analyzer, it is possible to analyze the electromagnetic radiation signal with lower power and obtain its signal parameters, and finally improve the accuracy of the unit electromagnetic radiation power density obtained by the detection, while also taking into account the cable assembly to the signal The insertion loss of the cable assembly is obtained by a vector network analyzer, the signal parameters are compensated, and the accuracy of the unit electromagnetic radiation power density is calculated using the compensated signal parameters, thereby further improving the detection accuracy.

As shown in FIG. 6, the present application also proposes an electromagnetic radiation detection method, which is applied to a system provided by the first or second embodiment of the electromagnetic radiation detection system of the present application. In this embodiment, the method includes:

S12: Use a receiving antenna to receive electromagnetic radiation signals in a preset area during the operation of the security detector.

S14: Use a spectrum analyzer to analyze the electromagnetic radiation signal to obtain signal parameters of the electromagnetic radiation signal.

S16: Calculate the power density of the electromagnetic radiation of the security checker by using the signal parameters and the parameters of the receiving antenna as known parameters.

Optionally, as shown in FIG. 7, step S16 specifically includes:

S161: Calculate the electromagnetic radiation power density of the security checker by using the signal parameter and the receiving antenna parameter as known parameters by using formula (1).

Further, before step S161, the method includes:

S160: Calculate the effective detection area of the receiving antenna by using formula (2).

Optionally, as shown in FIG. 7, after step S14, the method further includes:

S151: Use a vector network analyzer to obtain the insertion loss of the cable assembly.

S152: Use the insertion loss to compensate a signal parameter of the electromagnetic radiation signal.

Further, as shown in FIG. 8, step S16 includes:

S162: Calculate the power density of the electromagnetic radiation of the security detector by using the compensated signal parameters and the parameters of the receiving antenna as known parameters.

In this embodiment, after receiving the electromagnetic radiation signal of a preset area during the operation of the security inspection device by using a receiving antenna, the electromagnetic radiation signal is analyzed by using a spectrum analyzer, and the time domain signal parameters of the electromagnetic radiation signal are obtained to And the parameters of the receiving antenna are used to calculate the electromagnetic radiation power density of the security detector. Because of the higher accuracy of the spectrum analyzer, the signal parameters of the electromagnetic radiation signal with lower power can be obtained, and the accuracy of the calculated electromagnetic radiation power density is finally improved. In addition, in this embodiment, the attenuation of the signal by the cable assembly is further considered. After the vector cable analyzer is used to detect the insertion loss of the used cable assembly, it is compensated to the signal parameter of the electromagnetic radiation signal, so that the compensation is finally used. The accuracy of the electromagnetic radiation power density calculated by the subsequent signal parameters and the parameters of the receiving antenna is higher.

The above description is only an implementation of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of the application, or directly or indirectly applied to other related technologies The fields are equally covered by the patent protection scope of this application.

Claims

An electromagnetic radiation detection method, which is applied to an electromagnetic radiation detection system, the electromagnetic radiation detection system includes: a receiving antenna, a spectrum analyzer, a vector network analyzer, and a cable assembly; The spectrum analyzer is connected; the vector network analyzer is connected to the cable assembly; the method includes:

Using the receiving antenna to receive electromagnetic radiation signals in a preset area during the operation of the security detector;

Analyzing the electromagnetic radiation signal by using the spectrum analyzer, and obtaining signal parameters of the electromagnetic radiation signal;

Using the vector network analyzer to obtain the insertion loss of the cable component;

Using the insertion loss to compensate a signal parameter of the electromagnetic radiation signal;

Calculating the electromagnetic radiation power density of the security checker with the compensated signal parameters and the parameters of the receiving antenna as known parameters;

The signal parameter includes a time-domain signal peak of the electromagnetic radiation signal at a preset frequency point.
The method according to claim 1, wherein the parameters of the receiving antenna include an effective detection area of the receiving antenna;

The calculating the electromagnetic radiation power density of the security checker with the compensated signal parameters and the parameters of the receiving antenna as known parameters includes:

The following formula is used to calculate the power density of electromagnetic radiation of the security checker:

Wherein, q is the unit electromagnetic radiation power density of the security detector, P is the power value of the electromagnetic radiation signal received by the receiving antenna, and A is the effective detection area of the receiving antenna.
An electromagnetic radiation detection system, including: a receiving antenna, a spectrum analyzer, and a cable assembly;

The receiving antenna is connected to the spectrum analyzer through the cable assembly; the receiving antenna is used to receive an electromagnetic radiation signal in a preset area when the security checker works; the spectrum analyzer is used to analyze the electromagnetic radiation signal. A signal parameter to calculate an electromagnetic radiation power density of the security checker according to the signal parameter and a parameter of the receiving antenna.
The system according to claim 3, further comprising: a vector network analyzer connected to the cable assembly for obtaining an insertion loss of the cable assembly to utilize the insertion loss compensation The signal parameters.
The system according to claim 3, further comprising: a processing device, the processing device being connected to the spectrum analyzer for acquiring the signal parameters and calculating the electromagnetic radiation power density.
The system according to claim 4, further comprising: a processing device, wherein the processing device is connected to the spectrum analyzer and the vector network analyzer, respectively, for acquiring the signal parameter and the insertion loss, and using The insertion loss compensates the signal parameter, and calculates the electromagnetic radiation power density using the compensated signal parameter.
The system according to claim 3, wherein the signal parameter comprises a time-domain signal peak of the electromagnetic radiation signal at a preset frequency point.
The system of claim 3, wherein the receiving antenna is a standard gain horn antenna.
The system of claim 3, wherein the cable assembly is a length coaxial cable.
The system according to claim 3, wherein the preset area is a foot position of the receiving antenna when the antenna mouth surface is at a first preset distance from the inner glass of the security checker and when standing with a human body at the bottom of the security checker An area from a second preset distance.
The system according to claim 3, further comprising: a security detector for transmitting the electromagnetic radiation signal to detect a foreign object on the target.
An electromagnetic radiation detection method, which is applied to the electromagnetic radiation detection system according to claim 3, the method comprising:

Use a receiving antenna to receive electromagnetic radiation signals in a preset area when the security detector is working;

Use a spectrum analyzer to analyze the electromagnetic radiation signal and obtain signal parameters of the electromagnetic radiation signal;

The electromagnetic radiation power density of the security checker is calculated using the signal parameters and the parameters of the receiving antenna as known parameters.
The method according to claim 12, wherein the electromagnetic radiation detection system further comprises: a vector network analyzer, the vector network analyzer being connected to the cable assembly;

Before the calculating the electromagnetic radiation power density of the security checker using the signal parameter and the parameter of the receiving antenna as known parameters, the method includes:

The vector network analyzer is used to obtain the insertion loss of the cable component to compensate the signal parameter by using the insertion loss.
The method according to claim 13, wherein the electromagnetic radiation detection system further comprises: a processing device, the processing device being respectively connected to the spectrum analyzer and the vector network analyzer;

The obtaining the insertion loss of the cable component by using the vector network analyzer to compensate the signal parameter by using the insertion loss includes:

Acquiring, by the processor, the signal parameters from the spectrum analyzer, and acquiring the insertion loss from the vector network analyzer;

The processor compensates the signal parameter using the insertion loss, and calculates the electromagnetic radiation power density using the compensated signal parameter.
The method according to claim 12, wherein the signal parameter comprises a time-domain signal peak of the electromagnetic radiation signal at a preset frequency point.
The method according to claim 15, wherein the electromagnetic radiation detection system further comprises: a processing device connected to the spectrum analyzer; the parameters of the receiving antenna include an effective detection area of the receiving antenna;

The calculating the electromagnetic radiation power density of the security checker by using the signal parameter and the parameter of the receiving antenna as known parameters includes:

The processor obtains the signal parameters and an effective detection area of the receiving antenna, and calculates the electromagnetic radiation power density by using the following formula:

Wherein, q is the unit electromagnetic radiation power density of the security detector, P is the power value of the electromagnetic radiation signal received by the receiving antenna, and A is the effective detection area of the receiving antenna.
The method according to claim 12, wherein the receiving antenna is a standard gain horn antenna.
The method of claim 12, wherein the cable assembly is a length coaxial cable.
The method according to claim 12, wherein the preset area is a foot position of the receiving antenna when the antenna mouth surface is at a first preset distance from the glass of the security checker and when standing with a human body at the bottom of the security checker An area from a second preset distance.
The method according to claim 12, wherein the electromagnetic radiation detection system further comprises: a security checker, and the receiving antenna is disposed in the security checker;

Before the receiving an electromagnetic radiation signal in a preset area during operation of the security inspection device by using a receiving antenna, the method includes:

The security checker emits the electromagnetic radiation signal.