CN101520482A - Electromagnetic radiation sensitivity testing method for increasing test precision - Google Patents

Abstract

The invention discloses an electromagnetic radiation sensitivity testing method for increasing test precision, which comprises six steps: a single radiating antenna is used for radiating from a far field, and the radiating power of the antenna, the field intensity value of electric-field sensors and the distance between the antenna and the electric-field sensors are measured; a tested device is placed, and a plurality of electric-field sensors are arranged; the values of the electric-field sensors are recorded at the moment; the radiating antenna is approached to the tested device, the difference of the field intensity value at the moment and the field intensity measured in the last step is from 0dB to 6 dB, and the values of the electric-field sensors are recorded at the moment; the power of the radiating antenna is calculated in standard field intensity; and a sensitivity test is carried out. The invention gives out satisfying conditions between the radiation field intensity Elim prescribed by a testing standard and the radiation power P of the radiating antenna, utilizes an antenna theory to calculate the satisfying conditions between the power of the radiating antenna and the measuring field intensity value of a testing point when an internal coupling field of the tested device reaches the testing requirement and gives out a quantized calculating method, thereby increasing the precision of the electromagnetic radiation sensitivity test, and ensuring that a testing result is accurate and can repeatedly appear.

Description

A kind of electromagnetic radiation sensitivity method of testing that improves measuring accuracy

Technical field

The present invention relates to electromagnetic compatibility radiosensitivity method of testing, relate in particular to a kind of electromagnetic radiation sensitivity method of testing that improves measuring accuracy.

Background technology

According to GJB152A-97 " military equipment and subsystem Electromagnetic Launching and susceptibility are measured ", the radiosensitivity test is to be used for checking the ability that is subjected to examination equipment and relevant cable to bear radiated electric field in the electromagnetic compatibility test.

The frequency of electric field radiation sensitivity testing is from 10kHz～40GHz, even higher, covered the electromagnetic spectrum that major part has been utilized, is the most extensive, most important, also is one of the most representative sensitivity testing project.

The radiosensitivity test was promoted from the sixties in last century, so far in the military standard of a plurality of countries, as MIL-STD-461 series (American army mark), GJB151/152 series (British army's mark), Defence Standard 59-411 series (national military standard), and the civil standards of a plurality of systems, as ISO61000-4-6 etc.This test is widely used in the sensitivity characteristic of checkout equipment to electric interfering field.

This test derives from MIL-STD-461 series the earliest, continues to use in decades always, does not make an amendment substantially, has not been suitable for system-level test and development thereof in some field.Alternative methods such as TEM cell method, gtem cell method and big current injection method abroad when the improving one's methods of the system-level radiosensitivity test of research, occurred, but still do not break through on the size of equipment being tried.Reverberation chamber occurred the eighties in last century and sent out, and obtained extensive research in the nineties.This method can solve tests the large-scale radiosensitivity that is tried equipment, but the test result sensitivity characteristic of this method is a kind of statistical treatment data, how still need to study with traditional test result and be consistent, and method can't determine accurately that still susceptibility threshold etc. quantizes index.

The standards system of China is formulated with reference to American army mark, since GJB1389A not to the test method especially choosing of input power levels do clear and definite regulation, for the accuracy that guarantees to test, traditional scheme generally requires to select electric field radiation susceptibility measured power level with reference to the input power levels of the regulation of 10kHz～40GHz electric field radiation susceptibility among the GJB152A-97 " military equipment and subsystem Electromagnetic Launching and susceptibility are measured ".

Because the power magnitude mode in traditional electric field radiation sensitivity testing is adjusted main dependence tester's experience, subjective factor accounts for and has a significant impact the status, and the power magnitude that neither one quantizes limits, and can't provide the error quantization relation of test findings.

Summary of the invention

Order of the present invention is mainly to rely on tester's experience for power magnitude adjustment in the test of resolution system level electric field radiation susceptibility, and be not easy to reach the device interior coupled field needed homogeneity condition when test of being tried, and measuring accuracy can't be weighed, cause test result inaccurate, problems such as test result can't reappear have proposed a kind of electromagnetic radiation sensitivity method of testing that improves electromagnetic radiation sensitivity degree measuring accuracy.

The present invention can calculate the size of the required radiation power that applies of test, helps to test the accurate detection that realizes the radiosensitivity that is tried equipment full angle scope.By simulation homogeneous radiation field in being subjected to examination equipment, to reach the test condition of radiation emission test.

A kind of electromagnetic radiation sensitivity method of testing that improves measuring accuracy of the present invention specifically may further comprise the steps:

Step 1: place an electric-field sensor at the testing location that is tried the equipment place, use single radiating antenna to carry out radiation from the far field to electric-field sensor, the increase of starting from scratch of the output power of radiating antenna, output power value up to radiating antenna reaches the sensitivity of the field intensity of testing location above electric-field sensor, and the radiation power of record radiating antenna at this moment is P ₁, the distance between radiating antenna and the electric-field sensor is D ₁, the electric-field sensor measured value is E ₁

Step 2: place the examination equipment that is subjected at testing location, make that the center and the distance between the radiating antenna of the equipment that tried are D ₁, evenly place N electric-field sensor being tried device interior, use radiating antenna from the far field to being subjected to examination equipment to carry out radiation, the position of radiating antenna is identical with step 1 with radiation power.

Step 3: switch the electric-field sensor of diverse location, and the field strength distribution numerical value E of record electric-field sensor this moment ₁₁, E ₁₂... E _1N, wherein N is the number of electric-field sensor.

Step 4: with the hole seam place of radiating antenna near the stronger equipment that tried that radiated electric field is coupled, keep the position of the equipment that tried in the step 2 and the quantity and the layout of electric-field sensor, adjust the position and the radiated antenna power of radiating antenna, the feasible Electric Field Numerical E that this moment, electric-field sensor recorded ₂₁, E ₂₂... E _2NSatisfy following the requirement:

E ₂₁, E ₂₂... E _2NNumerical value satisfy 75% position at least and measure field intensity and E ₁₁, E ₁₂... E _1NThe absolute value of numerical difference between+0～+ 6dB, testing location is measured field intensity value E ₂₁, E ₂₂... E _2NSatisfy the relation of formula (1):

$|\sqrt{{\left(\frac{E_{21}}{E_{11}}\right)}^2+{\left(\frac{E_{22}}{E_{12}}\right)}^2+\·\·\·+{\left(\frac{E_{22}}{E_{12}}\right)}^2}/N-1|\≤\mathrm{\δ}---\left(1\right)$

Wherein, δ is the error magnitude, can specify according to customer requirements, and such as 0.01, wherein N is the electric-field sensor number of placement.

Under this condition, the field of being tried device interior is approximately uniform field, electric field value E ₂₁, E ₂₂... E _2NTried the electric field value E that device interior produces with the radiating antenna in the step 3 ₁₁, E ₁₂... E _1NEquivalence.Record radiated antenna power at this moment is P ₂, radiating antenna is D with the distance of being tried equipment ₂

Step 5: utilize the radiated antenna power P that obtains in the step 4 ₂, the field intensity value E that obtains of electric-field sensor monitoring ₂₁, E ₂₂... E _2N, obtain the radiation field intensity E that testing standard is stipulated _LimThe time, radiating antenna is D with the distance of being tried equipment ₂The time aerial radiation power P ₃

Step 6: according to radiating antenna in the step 5 and the distance D of being tried equipment ₂, the radiation power P of radiating antenna ₃, whether judgement is subjected to examination equipment responsive, if insensitive, then writes down insensitive; If sensitivity then write down sensitivity, and determine the responsive threshold level of the equipment that tried according to the method for regulation in army's mark.

The invention has the advantages that:

(1) extrapolates the radiation field intensity E that testing standard is stipulated with antenna theory _LimAnd between the radiation power P of radiating antenna the condition that should satisfy;

(2) extrapolate with antenna theory and tried power and test point that the device interior coupled field reaches test radiating antenna when needing and measure the condition that is satisfied between the field intensity value;

(3) change the experience that power magnitude mode in the electric field radiation sensitivity testing is in the past adjusted main dependence tester, subjective factor accounts for and has a significant impact the status, and the present invention has provided the power magnitude computing method of a quantification;

(4) improve the electromagnetic radiation sensitivity measuring accuracy, make test result accurate, test result can reappear.

Description of drawings

Fig. 1 is a process flow diagram of the present invention.

Embodiment

The present invention is described in further detail below in conjunction with accompanying drawing.

The present invention is a kind of electromagnetic radiation sensitivity method of testing that improves measuring accuracy, and flow process may further comprise the steps as shown in Figure 1:

Step 1: use single radiating antenna to carry out radiation from the far field at testing location, place an electric-field sensor at testing location, the increase of starting from scratch of the output power of radiating antenna, output power value up to radiating antenna reaches the sensitivity of the field intensity of testing location above electric-field sensor, and the radiation power of record radiating antenna at this moment is P ₁, the distance between radiating antenna and the electric-field sensor is D ₁, the electric-field sensor measured value is E ₁

The electric field of electric-field sensor reaches the electric field strength E of test regulation _LimThe time radiated antenna power P obtain by following steps:

If power amplifier output power is P _T(W), by antenna theory as can be known apart from the electric-field sensor received power P at radiating antenna R place _RFor

$P_R=\frac{P_T}{4\mathrm{\π}{R}^2}{G}_T\·S_e=\frac{P_T}{4\mathrm{\π}{R}^2}{G}_T\·\frac{{\mathrm{\λ}}^2}{4\mathrm{\π}}{G}_R---\left(2\right)$

G wherein _TBe radiating antenna gain, G _RBe electric-field sensor efficient, S _eBe the useful area of electric-field sensor, λ is the electromagnetic signal wavelength that electric-field sensor receives.

The electromagnetic Poynting vector S that electric-field sensor receives _R=E _R* H _R, in the far-field region, E _RBe the electric field that electric-field sensor receives, H _RFor the magnetic field that electric-field sensor receives, satisfy the free space condition simultaneously, E _R, H _RBoth are vertical mutually, and its ratio is constant 120 π.Poynting vector mould apart from radiating antenna R place is E _R ²/ 120 π, then radiating antenna radiation field intensity E _THave:

$E_T^2=\frac{120\mathrm{\π}{P}_T{G}_T{G}_R{\mathrm{\λ}}^2}{4\mathrm{\π}{R}^2\·4\mathrm{\π}}---\left(3\right)$

Equation (3) both sides evolution gets:

$E_T=\frac{\sqrt{30\mathrm{\π}{P}_T{G}_T{G}_R}\mathrm{\λ}}{2\mathrm{\πR}}---\left(4\right)$

The radiation power of radiating antenna is P ₁, the distance between radiating antenna and the electric-field sensor is D ₁, the electric-field sensor measured value is E ₁, the radiating antenna gain G _T, the electric-field sensor gain G _R, the electromagnetic wave signal wavelength X that receives and the electric field E of electric-field sensor ₁Between should satisfy formula (4), substitution obtains as shown in the formula (5):

$E_1=\frac{\sqrt{30\mathrm{\π}{P}_1{G}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}---\left(5\right)$

If it is E that the electric field of electric-field sensor reaches the electric field intensity numerical value of test regulation _Lim, radiating antenna is D with the distance of being tried equipment ₁The time radiated antenna power that needs be made as P, have according to formula (4):

$E_{\lim }=\frac{\sqrt{30\mathrm{\π}{\mathrm{PG}}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}---\left(6\right)$

Be divided by in (5) and (6) both sides:

$\frac{E_1}{E_{\lim }}=\frac{\sqrt{30\mathrm{\π}{P}_1{G}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}/\frac{\sqrt{30\mathrm{\π}{\mathrm{PG}}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}=\sqrt{\frac{P_1}{P}}---\left(7\right)$

Obtain after the arrangement:

$P=P_1\×{\left(\frac{E_{\lim }}{E_1}\right)}^2---\left(8\right)$

Step 2: be subjected to examination equipment in the testing location placement, center and the distance between the radiating antenna of being tried equipment are D ₁, evenly place N electric-field sensor being tried device interior, use radiating antenna to carry out radiation from the far field, the position of radiating antenna is identical with step 1 with radiation power.

Step 3: switch the electric-field sensor of diverse location, and the field strength distribution numerical value E of record electric-field sensor this moment ₁₁, E ₁₂... E _1N, wherein N is the number of electric-field sensor.

Step 4: with the hole seam place of radiating antenna near the stronger equipment that tried that radiated electric field is coupled, keep the position of the equipment that tried in the step 2 and the quantity and the layout of electric-field sensor, adjust the position and the radiated antenna power of radiating antenna, the feasible Electric Field Numerical E that this moment, electric-field sensor recorded ₂₁, E ₂₂... E _2NSatisfy following the requirement:

E ₂₁, E ₂₂... E _2NNumerical value satisfy 75% position at least and measure field intensity and E ₁₁, E ₁₂... E _1NThe absolute value of numerical difference between+0～+ 6dB, test point is measured field intensity value E ₂₁, E ₂₂... E _2NSatisfy formula (1) relation.

Under this condition, the field of being tried device interior is approximately uniform field, electric field value E ₂₁, E ₂₂... E _2NTried the electric field value E that device interior produces with the radiating antenna in the step 3 ₁₁, E ₁₂... E _1NEquivalence.Record radiated antenna power at this moment is P ₂, radiating antenna is D with the distance of being tried equipment ₂

Step 5: utilize the radiated antenna power P that obtains in the step 4 ₂, the field intensity value E that obtains of electric-field sensor monitoring ₂₁, E ₂₂... E _2N, obtain the radiation field intensity E that testing standard is stipulated _LimThe time, radiating antenna is D with the distance of being tried equipment ₂The time aerial radiation power P ₃

According to antenna theory, in order to make the E that the electric-field sensor monitoring obtains in the step 4 ₂₁, E ₂₂... E _2N, reach the radiation field intensity E that satisfies the testing standard regulation _Lim, the radiation power P of radiating antenna ₃And P ₁, P and P ₂Between should satisfy following relation:

$\frac{P_3}{P_2}=\frac{P}{P_1}---\left(9\right)$

(8) substitution (9) is obtained:

$P_3=P_2{\left(\frac{E_{\lim }}{E_1}\right)}^2---\left(10\right)$

Taking the logarithm in formula (10) both sides, and becomes the dB of unit to have unit conversion:

P _3(dB)＝P _2(dB)+(E _lim(dB)-E _1(dB)) (11)

Radiating antenna is with P _{3 (dB)}Radiation of power can make that being tried the device interior coupled field promptly reaches uniform field, can reach the field intensity value E of test request regulation again _{Lim (dB)}Increase radiated antenna power to performance number P ₃, can make and be tried the requirement that the device interior coupled field reaches the field uniformity of test needs.

Step 6: is D according to the radiating antenna in the step 5 with the distance of being tried equipment ₂, the radiation power of radiating antenna is P ₃, whether judgement is subjected to examination equipment responsive, if insensitive, then writes down insensitive; If sensitivity then write down sensitivity, and determine the responsive threshold level of the equipment that tried according to the method for regulation in army's mark.

Claims (1)

1, a kind of electromagnetic radiation sensitivity method of testing that improves measuring accuracy is characterized in that, may further comprise the steps:

Step 1: use single radiating antenna to carry out radiation from the far field at testing location, place an electric-field sensor at testing location, the increase of starting from scratch of the output power of radiating antenna, output power value up to radiating antenna reaches the sensitivity of the field intensity of testing location above electric-field sensor, and the radiation power of record radiating antenna at this moment is P ₁, the distance between radiating antenna and the electric-field sensor is D ₁, the electric-field sensor measured value is E ₁

The electric field of electric-field sensor reaches the electric field strength E of test regulation _LimThe time radiated antenna power P obtain by following steps:

If power amplifier output power is P _T(W), by antenna theory as can be known apart from the electric-field sensor received power P at radiating antenna R place _RFor

$P_R=\frac{P_T}{4\mathrm{\π}{R}^2}{G}_T\·S_e=\frac{P_T}{4\mathrm{\π}{R}^2}{G}_T\·\frac{{\mathrm{\λ}}^2}{4\mathrm{\π}}{G}_R---\left(1\right)$

G wherein _TBe radiating antenna gain, G _RBe electric-field sensor efficient, S _eBe the useful area of electric-field sensor, λ is the electromagnetic signal wavelength that electric-field sensor receives;

The electromagnetic Poynting vector S that electric-field sensor receives _R=E _R* H _R, in the far-field region, E _RBe the electric field that electric-field sensor receives, H _RFor the magnetic field that electric-field sensor receives, satisfy the free space condition simultaneously, E _R, H _RBoth are vertical mutually, and its ratio is constant 120 π, are E apart from the Poynting vector mould at radiating antenna R place _R ²/ 120 π, then radiating antenna radiation field intensity E _THave:

$E_T^2=\frac{120\mathrm{\π}{P}_T{G}_T{G}_R{\mathrm{\λ}}^2}{4\mathrm{\π}{R}^2\·4\mathrm{\π}}---\left(2\right)$

Equation (2) both sides evolution gets:

$E_T=\frac{\sqrt{30\mathrm{\π}{P}_T{G}_T{G}_R}\mathrm{\λ}}{2\mathrm{\πR}}---\left(3\right)$

The radiation power of radiating antenna is P ₁, the distance between radiating antenna and the electric-field sensor is D ₁, the electric-field sensor measured value is E ₁, the radiating antenna gain G _T, the electric-field sensor gain G _R, the electromagnetic wave signal wavelength X that receives and the electric field E of electric-field sensor ₁Between should satisfy formula (3), substitution obtains as shown in the formula (4):

$E_1=\frac{\sqrt{30\mathrm{\π}{P}_1{G}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}---\left(4\right)$

If it is E that the electric field of electric-field sensor reaches the electric field intensity numerical value of test regulation _Lim, radiating antenna is D with the distance of being tried equipment ₁The time radiated antenna power that needs be made as P, have according to formula (3):

$E_{\lim }=\frac{\sqrt{30\mathrm{\π}{\mathrm{PG}}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}---\left(5\right)$

Be divided by in (4) and (5) both sides:

$\frac{E_1}{E_{\lim }}=\frac{\sqrt{30\mathrm{\π}{P}_1{G}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}/\frac{\sqrt{30\mathrm{\π}{\mathrm{PG}}_T{G}_R}\mathrm{\λ}}{2\mathrm{\π}{D}_1}=\sqrt{\frac{P_1}{P}}---\left(6\right)$

Obtain after the arrangement:

$P=P_1\×{\left(\frac{E_{\lim }}{E_1}\right)}^2---\left(7\right)$

Step 2: be subjected to examination equipment in the testing location placement, center and the distance between the radiating antenna of being tried equipment are D ₁, evenly place N electric-field sensor being tried device interior, use radiating antenna to carry out radiation from the far field, the position of radiating antenna is identical with step 1 with radiation power;

Step 3: switch the electric-field sensor of diverse location, and the field strength distribution numerical value E of record electric-field sensor this moment ₁₁, E ₁₂... E _1N, wherein N is the number of electric-field sensor;

Step 4: with the hole seam place of radiating antenna near the stronger equipment that tried that radiated electric field is coupled, keep the position of the equipment that tried in the step 2 and the quantity and the layout of electric-field sensor, adjust the position and the radiated antenna power of radiating antenna, the feasible Electric Field Numerical E that this moment, electric-field sensor recorded ₂₁, E ₂₂... E _2NSatisfy following the requirement:

E ₂₁, E ₂₂... E _2NNumerical value satisfy 75% position at least and measure field intensity and E ₁₁, E ₁₂... E _1NThe absolute value of numerical difference between+0～+ 6dB, test point is measured field intensity value E ₂₁, E ₂₂... E _2NSatisfy formula (8) relation;

$|\sqrt{{\left(\frac{E_{21}}{E_{11}}\right)}^2+{\left(\frac{E_{22}}{E_{12}}\right)}^2+\·\·\·+{\left(\frac{E_{22}}{E_{12}}\right)}^2}/N-1|\≤\mathrm{\δ}---\left(8\right)$

Wherein, δ is the error magnitude, can specify according to customer requirements, wherein the electric-field sensor number of N for placing;

Under this condition, the field of being tried device interior is approximately uniform field, electric field value E ₂₁, E ₂₂... E _2NTried the electric field value E that device interior produces with the radiating antenna in the step 3 ₁₁, E ₁₂... E _1NEquivalence; Record radiated antenna power at this moment is P ₂, radiating antenna is D with the distance of being tried equipment ₂

Step 5: utilize the radiated antenna power P that obtains in the step 4 ₂, the field intensity value E that obtains of electric-field sensor monitoring ₂₁, E ₂₂... E _2N, obtain the radiation field intensity E that testing standard is stipulated _LimThe time, radiating antenna is D with the distance of being tried equipment ₂The time aerial radiation power P ₃

According to antenna theory, in order to make the E that the electric-field sensor monitoring obtains in the step 4 ₂₁, E ₂₂... E _2N, reach the radiation field intensity E that satisfies the testing standard regulation _1im, the radiation power P of radiating antenna ₃And P ₁, P and P ₂Between should satisfy following relation:

$\frac{P_3}{P_2}=\frac{P}{P_1}---\left(9\right)$

(7) substitution (9) is obtained:

$P_3=P_2{\left(\frac{E_{\lim }}{E_1}\right)}^2---\left(10\right)$

Taking the logarithm in formula (10) both sides, and becomes the dB of unit to have unit conversion:

P _3(dB)＝P _2(dB)+(E _lim(dB)-E _1(dB)) (11)

Radiating antenna is with P _{3 (dB)}Radiation of power can make that being tried the device interior coupled field promptly reaches uniform field, can reach the field intensity value E of test request regulation again _{Lim (dB)}Increase radiated antenna power to performance number P ₃, can make and be tried the requirement that the device interior coupled field reaches the field uniformity of test needs;

Step 6: is D according to the radiating antenna in the step 5 with the distance of being tried equipment ₂, the radiation power of radiating antenna is P ₃, whether judgement is subjected to examination equipment responsive, if insensitive, then writes down insensitive; If sensitivity then write down sensitivity, and determine the responsive threshold level of the equipment that tried according to the method for regulation in army's mark.

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