阅读说明：本技术 一种基于瞬态电磁环境的设备敏感指标设计方法 (Equipment sensitivity index design method based on transient electromagnetic environment ) 是由 李尧尧 胡宗奇 蔡少雄 苏东林 于 2021-08-30 设计创作，主要内容包括：本发明公开了一种基于瞬态电磁环境的设备敏感指标设计方法,包括以下步骤：S1.构建系统模型,并确定瞬态电磁进入系统的途径和影响系统的方式；S2.给定瞬态电磁场辐射敏感度指标；S3.基于给定的瞬态电磁场辐射敏感度指标,对系统模型内的敏感阈值进行计算；S4.根据计算的敏感阈值与系统模型中部件的设计指标,综合确定系统内的敏感阈值指标。本发明对设备互连线缆和接收天线的抗干扰指标进行设计,以保证其在瞬态电磁环境下的生存特性,有抵御给定的电磁环境干扰的能力,并有一定的安全余量。(The invention discloses a method for designing equipment sensitivity indexes based on a transient electromagnetic environment, which comprises the following steps: s1, constructing a system model, and determining a way for transient electromagnetism to enter a system and a way for influencing the system; s2, giving a transient electromagnetic field radiation sensitivity index; s3, calculating a sensitivity threshold value in the system model based on a given transient electromagnetic field radiation sensitivity index; and S4, comprehensively determining the sensitivity threshold index in the system according to the calculated sensitivity threshold and the design index of the component in the system model. The invention designs the anti-interference indexes of the equipment interconnection cable and the receiving antenna so as to ensure the survival characteristic of the equipment interconnection cable and the receiving antenna under the transient electromagnetic environment, has the capability of resisting the given electromagnetic environment interference and has certain safety margin.)

1. A method for designing equipment sensitivity indexes based on a transient electromagnetic environment is characterized by comprising the following steps: the method comprises the following steps:

s1, constructing a system model, and determining a way for transient electromagnetism to enter a system and a way for influencing the system;

s2, giving a transient electromagnetic field radiation sensitivity index;

s3, calculating a sensitivity threshold value in the system model based on a given transient electromagnetic field radiation sensitivity index;

and S4, comprehensively determining the sensitivity threshold index in the system according to the calculated sensitivity threshold and the design index of the component in the system model.

2. The method for designing the equipment sensitivity index based on the transient electromagnetic environment according to claim 1, wherein the method comprises the following steps: the system model comprises a system shell with a hole seam, an antenna is arranged on the system shell, and a plurality of devices are arranged in the system shell; the device comprises a receiver connected to an antenna by a radio frequency line, and a receiving device interconnected by a cable, the cable comprising a signal line and a control line;

the transient electromagnetic environment enters the system through a front door coupling way and a rear door coupling way; the front door coupling means that the front door enters a system through an antenna and influences a receiver connected with the antenna; the back door coupling means that the back door enters the system through a hole gap, a coupling effect is generated on the cable, and the receiving equipment interconnected through the cable is influenced.

3. The method for designing the equipment sensitivity index based on the transient electromagnetic environment according to claim 1, wherein the method comprises the following steps: the transient electromagnetic field radiation sensitivity index aims at the capability of the whole system in the transient electromagnetic environment, and is obtained through an RS105 test or is directly preset.

4. The method for designing the equipment sensitivity index based on the transient electromagnetic environment according to claim 1, wherein the method comprises the following steps: in step S3, when the electromagnetic field enters the system enclosure through the back door coupling, the radiation value of the electromagnetic environment inside the system enclosure is estimated:

P_{in E}＝P_{E. Outer cover}-L

Wherein P is_{In E}The unit is the environmental index of the electromagnetic field inside the system: dBV/m; p_{E outer}The unit is the overall design index of the system: dBV/m; l is the shielding effectiveness of the housing, unit: dB;

the electromagnetic environment inside the shell generates a coupling effect on the cable, flows into the receiving equipment through a cable port, is closely related to the length, layout and ground clearance of the cable, and needs to establish a relation function F(s) of an internal field and a cable common-mode coupling effect and a relation function H(s) of an internal field and a cable differential-mode coupling effect to decompose the electromagnetic compatibility index of the cable, and then calculates the cable common-mode current and the differential-mode voltage according to the relation functions:

I_{common mode}＝E_{Inner part}·F(s)

U_{Differential mode}＝E_{Inner part}·H(s)

Wherein E is_{Inner part}Representing the field strength of the system's internal field environment according to P_{In E}＝20lgE_{Inner part}Calculating to obtain a unit V/m; converting the sensitive threshold values of the common-mode current and the differential-mode voltage into a dB form, and reserving 6dB design margin to obtain the sensitive threshold values of the common-mode current and the differential-mode voltage of the cable:

。

5. the method for designing the equipment sensitivity index based on the transient electromagnetic environment according to claim 1, wherein the method comprises the following steps: in step S3, when the electromagnetic field enters the system housing through the front door coupling, the radiation field generates a coupling effect on the rf line connected to the antenna, the radiation field is injected into the receiver inside the system housing through the rf port, and the port induced voltage is obtained by establishing a coupling effect relation function H' (S) between the field environment and the rf line:

U_{differential mode}＝E_{Outer cover}·H′(s)

E_{Outer cover}Representing the transient electromagnetic environment outside the system for the radiation sensitivity index of the transient electromagnetic field;

s303, let R be the equivalent load of the radio frequency line port, that is, the power of the port load is:

wherein, U_{Differential mode}For sensing load voltage, according to the sensitivity threshold S_Port(s)＝10lgP_Port(s)A design margin of 6dB is left, thus deducing the antenna receiver sensitivity threshold S:

wherein S is_Port(s)Antenna port power, unit: dBm, f_downLower frequency limit of the receiving antenna, f_upIs the lower frequency limit of the receiving antenna; f. of_elseIs represented by [ f_down,f_up]Outside frequency band, phi_fIndicating that the device is in the test frequency band f_testThe degree of inhibition.

6. The method for designing the equipment sensitivity index based on the transient electromagnetic environment according to claim 1, wherein the method comprises the following steps: the step S4 includes:

s401, regarding the cable connected with the receiving equipment in the system shell, the sensitive threshold values of the common-mode current and the differential-mode voltage obtained in the step S3 are marked as C_iI is 1,2, wherein when i is 1, the corresponding C_iIs P_I(ii) a When i is 2, corresponding C_iIs P_U(ii) a Obtaining a sensitivity threshold K of the cable itself_iWhere i is 1, corresponding to K_iA common-mode current sensitivity threshold representing the cable itself; when i is 2, corresponding K_iA differential mode voltage sensitive threshold representing the cable itself;

c is to be_iAnd K_iComparing, and taking the harsher index as the sensitive design index Q of the system in the transient electromagnetic environment_i：

Q_i＝max(K_i，C_i)，i＝1,2

Sensitive design index Q_iAs a final cable sensitivity threshold indicator;

s402, for a receiver connected with an antenna through a radio frequency line, setting the sensitivity of the receiver per se in a working frequency band as L_f,f∈[f_down,f_up]Wherein f is_downAnd f_upRespectively representing the lower limit and the upper limit of the working frequency range of the equipment;

given receiver antenna terminal out-of-band response rejection R_f,f∈f_elseFrom L_fAnd R_fThe receiver sensitivity threshold function S' of the electronic device is obtained by integration as shown in the following formula:

and taking the index max (S, S ') with severer S' and S as the sensitive design index of the receiver.

7. The method for designing the equipment sensitivity index based on the transient electromagnetic environment according to claim 5, wherein the method comprises the following steps: in the step S401, a sensitivity threshold K of the cable itself is obtained_iThe method comprises the following steps:

(1) testing the cable, and directly testing the sensitive threshold values of the common-mode current and the differential-mode voltage of the cable;

(2) according to the cable condition, sensitive thresholds of the cable common mode current and differential mode voltage are preset.

Technical Field

The invention relates to electromagnetic sensitivity index decomposition, in particular to a method for designing equipment sensitivity indexes based on a transient electromagnetic environment.

Background

Electromagnetic susceptibility refers to the ability to withstand electromagnetic interference in the presence of electromagnetic disturbance, i.e., the ability to function properly as required in a given electromagnetic environment. With the continuous development of science and technology, the spectrum of the transient electromagnetic environment is wider and stronger, electronic devices, equipment and systems tend to be miniaturized, integrated, complicated, high-sensitivity, high-power, high-speed and broadband, and accompanying problems are that the anti-interference capability of the components is poorer and poorer, and the components are easily influenced by the transient electromagnetic pulse environment (such as nuclear electromagnetic pulse, thunder, high-power microwave and the like), so that the electromagnetic sensitivity of the system in the transient electromagnetic environment is more and more concerned by engineering technicians.

Transient electromagnetic environment mainly gets into the system through two kinds of ways of front door coupling (radio frequency port such as antenna) and back door coupling (aperture, cable etc.), and the field that gets into through antenna, aperture coupling influences equipment with the mode that the radiation is sensitive mostly, and the field that gets into through cable coupling influences equipment with the mode that the conduction is sensitive mostly, for guaranteeing that transient electromagnetic environment does not influence system normal work, need urgently to carry out electromagnetic sensitivity index design to the system, makes it satisfy the interference killing feature limit value that is applicable to transient electromagnetic environment.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a method for designing the equipment sensitivity index based on the transient electromagnetic environment, which designs the sensitivity of an equipment interconnection cable and a receiver so as to ensure the survival characteristic of the equipment interconnection cable and the receiver under the transient electromagnetic environment, has the capability of resisting the given electromagnetic environment interference and has certain safety margin.

The purpose of the invention is realized by the following technical scheme: a method for designing equipment sensitivity indexes based on a transient electromagnetic environment comprises the following steps:

s1, constructing a system model, and determining a way for transient electromagnetism to enter a system and a way for influencing the system;

s2, giving a transient electromagnetic field radiation sensitivity index;

s3, calculating a sensitivity threshold value in the system model based on a given transient electromagnetic field radiation sensitivity index;

and S4, comprehensively determining the sensitivity threshold index in the system according to the calculated sensitivity threshold and the design index of the component in the system model.

Preferably, the system model comprises a system housing with a slot, an antenna is arranged on the system housing, and a plurality of devices are arranged in the system housing; the device comprises a receiver connected to an antenna by a radio frequency line, and a receiving device interconnected by a cable, the cable comprising a signal line and a control line;

the transient electromagnetic environment enters the system through a front door coupling way and a rear door coupling way; the front door coupling means that the front door enters a system through an antenna and influences a receiver connected with the antenna; the back door coupling means that the back door enters the system through a hole gap, a coupling effect is generated on the cable, and the receiving equipment interconnected through the cable is influenced.

Preferably, the transient electromagnetic field radiation sensitivity index is obtained by RS105 test or is directly preset aiming at the capability of the whole system to bear the transient electromagnetic environment.

In step S3, when the electromagnetic field enters the system enclosure through the back door coupling, the radiation value of the electromagnetic environment inside the system enclosure is estimated:

P_{in E}＝P_{E. Outer cover}-L

Wherein P is_{In E}The unit is the environmental index of the electromagnetic field inside the system: dBV/m; p_{E outer}The unit is the overall design index of the system: dBV/m; l is the shielding effectiveness of the housing, unit: dB;

the electromagnetic environment inside the shell generates a coupling effect on the cable, flows into the receiving equipment through a cable port, is closely related to the length, layout and ground clearance of the cable, and needs to establish a relation function F(s) of an internal field and a cable common-mode coupling effect and a relation function H(s) of an internal field and a cable differential-mode coupling effect to decompose the electromagnetic compatibility index of the cable, and then calculates the cable common-mode current and the differential-mode voltage according to the relation functions:

I_{common mode}＝E_{Inner part}·F(s)

U_{Differential mode}＝E_{Inner part}·H(s)

Wherein E is_{Inner part}Representing the field strength of the system's internal field environment according to P_{In E}＝20lgE_{Inner part}Calculating to obtain a unit V/m; shape converting sensitivity threshold of common mode current and differential mode voltage into dBAnd (3) obtaining the sensitivity threshold values of the common-mode current and the differential-mode voltage of the cable by reserving a design margin of 6 dB:

。

in step S3, when the electromagnetic field enters the system housing through the front door coupling, the radiation field generates a coupling effect on the rf line connected to the antenna, the radiation field is injected into the receiver inside the system housing through the rf port, and the port induced voltage is obtained by establishing a coupling effect relation function H' (S) between the field environment and the rf line:

U_{differential mode}＝E_{Outer cover}·H′(s)

E_{Outer cover}Representing the transient electromagnetic environment outside the system for the radiation sensitivity index of the transient electromagnetic field;

s303, let R be the equivalent load of the radio frequency line port, that is, the power of the port load is:

wherein, U_{Differential mode}For sensing load voltage, according to the sensitivity threshold S_Port(s)＝10lgP_Port(s)A design margin of 6dB is left, thus deducing the antenna receiver sensitivity threshold S:

wherein S is_Port(s)Antenna port power, unit: dBm, f_downLower frequency limit of the receiving antenna, f_upIs the lower frequency limit of the receiving antenna; f. of_elseIs represented by [ f_down,f_up]Outside frequency band, phi_fIndicating that the device is in the test frequency band f_testThe degree of inhibition.

The step S4 includes:

s401, for the cables connected with the receiving equipment in the system shell, the cables obtained in the step S3 are calculatedThe sensitive thresholds for the common mode current and differential mode voltage are labeled C_iI is 1,2, wherein when i is 1, the corresponding C_iIs P_I(ii) a When i is 2, corresponding C_iIs P_U(ii) a Obtaining a sensitivity threshold K of the cable itself_iWhere i is 1, corresponding to K_iA common-mode current sensitivity threshold representing the cable itself; when i is 2, corresponding K_iA differential mode voltage sensitive threshold representing the cable itself;

c is to be_iAnd K_iComparing, and taking the harsher index as the sensitive design index Q of the system in the transient electromagnetic environment_i：

Q_i＝max(K_i，C_i)，i＝1,2

Sensitive design index Q_iAs a final cable sensitivity threshold indicator;

s402, for a receiver connected with an antenna through a radio frequency line, setting the sensitivity of the receiver per se in a working frequency band as L_f,f∈[f_down,f_up]Wherein f is_downAnd f_upRespectively representing the lower limit and the upper limit of the working frequency range of the equipment;

given receiver antenna terminal out-of-band response rejection R_f,f∈f_elseFrom L_fAnd R_fThe receiver sensitivity threshold function S' of the electronic device is obtained by integration as shown in the following formula:

and taking the index max (S, S ') with severer S' and S as the sensitive design index of the receiver.

In step S401, a sensitivity threshold K of the cable itself is obtained_iThe method comprises the following steps:

(1) testing the cable, and directly testing the sensitive threshold values of the common-mode current and the differential-mode voltage of the cable;

(2) according to the cable parameters, sensitive thresholds of the cable common mode current and the differential mode voltage are preset.

The invention has the beneficial effects that: the invention designs the sensitivity of the device interconnection cable and the receiver so as to ensure the survival characteristic of the device interconnection cable and the receiver under the transient electromagnetic environment, has the capability of resisting the given electromagnetic environment interference and has certain safety margin.

Drawings

FIG. 1 is a flow chart of a method of the present invention;

fig. 2 is a graph of the radiation field relationship of the cable.

Detailed Description

The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings, but the scope of the present invention is not limited to the following.

As shown in fig. 1, a method for designing a device sensitivity index based on a transient electromagnetic environment includes the following steps:

s1, constructing a system model, and determining a way for transient electromagnetism to enter a system and a way for influencing the system;

s2, giving a transient electromagnetic field radiation sensitivity index;

s3, calculating a sensitivity threshold value in the system model based on a given transient electromagnetic field radiation sensitivity index;

and S4, comprehensively determining the sensitivity threshold index in the system according to the calculated sensitivity threshold and the design index of the component in the system model.

In an embodiment of the application, the system model includes a system housing with a slot, an antenna is disposed on the system housing, and a plurality of devices are disposed in the system housing; the device comprises a receiver connected to an antenna by a radio frequency line, and a receiving device interconnected by a cable, the cable comprising a signal line and a control line;

the transient electromagnetic environment enters the system through a front door coupling way and a rear door coupling way; the front door coupling means that the front door enters a system through an antenna and influences a receiver connected with the antenna; the back door coupling means that the back door enters the system through a hole gap, a coupling effect is generated on the cable, and the receiving equipment interconnected through the cable is influenced.

Preferably, the transient electromagnetic field radiation sensitivity index is obtained by RS105 test or is directly preset aiming at the capability of the whole system to bear the transient electromagnetic environment.

In step S3, when the electromagnetic field enters the system enclosure through the back door coupling, the radiation value of the electromagnetic environment inside the system enclosure is estimated:

P_{in E}＝P_{E. Outer cover}-L

Wherein P is_{In E}The unit is the environmental index of the electromagnetic field inside the system: dBV/m; p_{E outer}The unit is the overall design index of the system: dBV/m; l is the shielding effectiveness of the housing, unit: dB;

the electromagnetic environment in the shell generates a coupling effect on the cable, flows into the receiving equipment through a cable port, is closely related to the length, layout and ground clearance of the cable, and needs to establish a relation function F(s) of an internal field and a common mode coupling effect of the cable and a relation function H(s) of an internal field and a differential mode coupling effect of the cable for decomposing the electromagnetic compatibility index of the cable, wherein the relation functions F(s) and H(s) can be obtained by a simulation or test method and serve as a known function which is determined in advance in the actual application process; and then calculating the common-mode current and the differential-mode voltage of the cable according to the following steps:

I_{common mode}＝E_{Inner part}·F(s)

U_{Differential mode}＝E_{Inner part}·H(s)

Wherein E is_{Inner part}Representing the field strength of the system's internal field environment according to P_{In E}＝20lgE_{Inner part}Calculating to obtain a unit V/m; converting the sensitive threshold values of the common-mode current and the differential-mode voltage into a dB form, and reserving 6dB design margin to obtain the sensitive threshold values of the common-mode current and the differential-mode voltage of the cable:

。

in step S3, when the electromagnetic field enters the system housing through the front door coupling, the radiation field generates a coupling effect on the rf line connected to the antenna, the radiation field is injected into the receiver inside the system housing through the rf port, the radiation field is obtained by establishing a coupling effect relation function H '(S) between the field environment and the rf line, and the H' (S) is obtained through simulation or experimental test, and in the actual application process, the radiation field is used as a predetermined known function to calculate the port induced voltage:

U_{differential mode}＝E_{Outer cover}·H′(s)

E_{Outer cover}Representing the transient electromagnetic environment outside the system for the radiation sensitivity index of the transient electromagnetic field;

s303, let R be the equivalent load of the radio frequency line port, that is, the power of the port load is:

wherein, U_{Differential mode}For sensing load voltage, according to the sensitivity threshold S_Port(s)＝10lgP_Port(s)A design margin of 6dB is left, thus deducing the antenna receiver sensitivity threshold S:

wherein S is_Port(s)Antenna port power, unit: dBm, f_downLower frequency limit of the receiving antenna, f_upIs the lower frequency limit of the receiving antenna; f. of_elseIs represented by [ f_down,f_up]Outside frequency band, phi_fIndicating that the device is in the test frequency band f_testThe suppression degree can be directly given, and can also be obtained through the antenna terminal sensitive items CS103, CS104, CS105 test.

The step S4 includes:

s401, regarding the cable connected with the receiving equipment in the system shell, the sensitive threshold values of the common-mode current and the differential-mode voltage obtained in the step S3 are marked as C_iI is 1,2, wherein when i is 1, the corresponding C_iIs P_I(ii) a When i is 2, corresponding C_iIs P_U(ii) a Obtaining a sensitivity threshold K of the cable itself_iWhere i is 1, corresponding to K_iA common-mode current sensitivity threshold representing the cable itself; when i is 2, pairShould be K_iA differential mode voltage sensitive threshold representing the cable itself;

obtaining a sensitivity threshold K of the cable itself_iThe method comprises the following steps:

(1) testing the cable, and directly testing the sensitive threshold values of the common-mode current and the differential-mode voltage of the cable; if the test is needed, the sensitive threshold value of the differential mode voltage can be obtained through the CS101 or CS106 test; the common-mode current sensitive threshold value can be obtained through CS114, CS115 or CS116 tests;

(2) according to the cable condition, sensitive thresholds of the cable common mode current and differential mode voltage are preset.

C is to be_iAnd K_iComparing, and taking the harsher index as the sensitive design index Q of the system in the transient electromagnetic environment_i：

Q_i＝max(K_i，C_i)，i＝1,2

Sensitive design index Q_iAs a final cable sensitivity threshold indicator;

for a receiver connected with an antenna through a radio frequency line, the sensitivity of the receiver per se in a working frequency band is set to be L_f,f∈[f_down,f_up]Wherein f is_downAnd f_upRespectively representing the lower limit and the upper limit of the working frequency range of the equipment;

given receiver antenna terminal out-of-band response rejection R_f,f∈f_else,(R_f＝φ_f) From L_fAnd R_fThe receiver sensitivity threshold function S' of the electronic device is obtained by integration as shown in the following formula:

and taking the index max (S, S ') with severer S' and S as the sensitive design index of the receiver.

The invention designs the anti-interference indexes of the equipment interconnection cable and the receiver so as to ensure the survival characteristic of the equipment interconnection cable and the receiver under the transient electromagnetic environment, has the capability of resisting the given electromagnetic environment interference and has certain safety margin.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.