Testing and measurement techniques — Radiated, radio-frequency electromagnetic field immunity test
IEC 61000-4-3-2020 pdf download.Electromagnetic compatibility (EMC) — Part 4-3: Testing and measurement techniques — Radiated, radio-frequency electromagnetic field immunity test.
6.3.2 Constant field strength level setting method The constant field strength of the uniform field shall be:
• established at each particular frequency. The particular frequencies are determined by using the frequency step described in 8.4
• established at each of the points of the UFA, one after the other (see Figure 4);
• established by adjusting the forward power accordingly.
• measured via a calibrated field sensor.
The forward power necessary to establish the field strength chosen shall be measured in
accordance with Figure 6 and is to be recorded in dBm for the sixteen points. Procedure to be followed at both horizontal and vertical polarizations:
a) Position the sensor at one of the sixteen points in the grid (see Figure 4), and set the frequency of the signal generator output to the lowest frequency in the range of the test (for example 80 MHz).
NOTE 1 To lower the uncertainty of the field measurement, the probe is oriented in the same manner at each
of the grid points as it was oriented during the probe calibration.
b) Adjust the forward power to the field generating antenna so that the field strength obtained (with field probe correction factors for frequency applied) is equal to the level setting field strength EL. Record the forward power reading.
C) Increase the frequency using the step size given in Clause 8.
d) Repeat steps b) and c) until the next frequency in the sequence would exceed the highest frequency In the range of the test. Finally, repeat step b) at the maximum frequency of the test range (for example 1 GHz).
e) Repeat steps a) to d) for each point in the grid.
At each frequency:
1) Sort the sixteen forward power readings into ascending order.
2) Start at the highest value and check if at least the eleven readings below this value (75 % of grid points) are within the tolerance of —6 dB to 0 dB of that value.
6.3.3 Constant power level setting method
The field strength of the uniform field shall be established and measured via a calibrated field sensor at each particular frequency and at each of the sixteen points one after the other (see Figure 4) using the step size given in 8.4 and adjusting the forward power accordingly.
The forward power necessary to establish the field strength at the starting position shall be measured in accordance with Figure 6, and noted. The same forward power shall be applied for all sixteen positions. The field strength created by this forward power is to be recorded at each of the sixteen points.
Procedure to be followed at both horizontal and vertical polarizations:
a) Position the sensor at one of the sixteen points in the grid (see Figure 4), and set the frequency of the signal generator output to the lowest frequency in the range of the test (for example 80 MHz).
NOTE 1 To lower the uncertainty ol the tield measurement, the probe is oñented In the same manner at each of the grid points as it was described in the probe calibration report.
b) Apply a forward power to the field generating antenna so that the field strength obtained (with field probe correction factors for frequency applied) equals EL. Record the forward power and field strength readings
c) Increase the frequency using the step size given in Clause 8.
d) Repeat steps b) and C) until the next frequency in the sequence would exceed the highest frequency in the range of the test. Finally, repeat step b) at the maximum frequency of the test range (for example 1 GHz).
e) Move the sensor to another position in the grid. At each of the frequencies used in steps a) to d). apply the forward power recorded in step b) for that frequency, and record the field strength reading.
f) Repeat step e) for each point in the grid.
At each frequency:
1) Sort the sixteen field strength readings into ascending order.IEC 61000-4-3-2020 pdf download.