How to perform a MIL-STD-461 RE102 Radiated Emission test[edit]
This application note explains how the MIL-STD-461 RE102 Radiated Emission test can be performed with RadiMation®.
The "RE102, radiated emissions, electrical field" test is applicable to equipment, subsystem enclosures and all interconnecting cables and is used to verify that the electrical field emissions from the EUT and cabling do not exceed the specified requirements. Other standards are based on this test (for example DO160) and those tests are very comparable to this test.
The exact requirements and test methods for the RE102 are specified in the MIL-STD-461. Depending on the tested product, the complete or a partial frequency range should be tested.
Necessary equipment[edit]
The following devices should be configured:
- Receiver
- One or more antennas
- Cables
Depending on the frequency range that should be measured, up to four different antennas may be needed.
| Antenna |
Frequency range
|
| Rod antenna |
10 kHz to 30 MHz
|
| Biconical antenna |
30 MHz to 200 MHz
|
| Double ridge horn |
200 MHz to 1 GHz
|
| Double ridge horn |
1 GHz to 18 GHz
|
Optionally[edit]
- Antenna polarizer / tower, because above 30 MHz both vertical and horizontal polarizations should be measured.
Configuration of the testsites[edit]
The configuration of the equipment is an antenna connected with a cable to a receiver.
The configuration of the testsite should thus contain the following devices:
| Device name |
Tab in testsite configuration window |
note
|
| Antenna |
Devices 1 |
Antenna for the required frequency range
|
| Antenna tower |
Devices 1 |
Optional antenna tower
|
| Spectrum Analyser |
Devices 2 |
The receiver used for the test
|
| Cable preamp -> analyser |
Cables |
Cable with a correction file specified for the loss
|
As different antennas are used for each frequency range, it is best to also create and configure multiple separate testsites. Each testsite will use a different antenna, and to make the distinction between the testsites, it is best to give them different names. For example like:
| Testsite |
Antenna
|
| MIL-STD RE102 10 kHz - 30 MHz |
Rod antenna
|
| MIL-STD RE102 30 MHz - 200 MHz |
Biconical antenna
|
| MIL-STD RE102 200 MHz - 1 GHz |
Horn antenna
|
| MIL-STD RE102 1 GHz - 18 GHz |
Horn antenna
|
Perform the test[edit]
To perform the actual RE102 test, start a Radiated Emission Multiband test:
-
Tests
- Radiated Emission
- Multiband
The complete test from 10 kHz up to 18 GHz has different settings for different frequency bands. All these different bands can be configured.
The test can be configured with 6 bands each using their applicable frequency range, bandwidth, polarization and used testsite (antenna).
When it is not possible to automatically switch and or position the antenna, multiple tests can be created and executed separately.
| Band |
Frequency range |
RBW |
Step size |
Measure time receiver |
Measure time FFT receiver |
Polarization |
Testsite |
Antenna
|
| Band 1 |
10 kHz - 150 kHz |
1 kHz |
500 Hz |
0.15 s |
1 s |
Vertical |
MIL-STD RE102 (10 kHz - 30 MHz) |
Rod antenna
|
| Band 2 |
150 kHz - 10 MHz |
10 kHz |
5 kHz |
0.015 s |
1 s |
Vertical |
MIL-STD RE102 (150 kHz - 30 MHz) |
Rod antenna
|
| Band 3 |
10 MHz - 30 MHz |
10 kHz |
5 kHz |
0.015 s |
0.15 s |
Vertical |
MIL-STD RE102 (150 kHz - 30 MHz) |
Rod antenna
|
| Band 4 |
30 MHz - 200 MHz |
100 kHz |
50 kHz |
0.015 s |
0.15 s |
Both |
MIL-STD RE102 (30 MHz - 200 MHz) |
Biconical antenna
|
| Band 5 |
200 MHz - 1 GHz |
100 kHz |
50 kHz |
0.015 s |
0.15 s |
Both |
MIL-STD RE102 (200 MHz - 1 GHz) |
Horn antenna
|
| Band 6 |
1 GHz - 18 GHz |
1 MHz |
500 kHz |
0.015 s |
0.015 s |
Both |
MIL-STD RE102 (1 GHz - 18 GHz) |
Horn antenna
|
For more information regarding required antenna positions refer to section 5.18.3.3 c. EUT testing, of the MIL-STD-461 RE102 standard.
To automatically change the antenna position, an antenna tower could be used. When no antenna tower is available, multiple positions (heights) could be tested using a "Manual Controlled Antenna Tower", the "Manual Controlled Antenna Tower" will prompt the end-user to move the antenna manually when applicable.
In the following test setup, an EUT for "Ground applications, Navy Mobile & Army" is tested. This limit line starts at 2 MHz and ends at 18 GHz, therefore this test does not include the test site for "Band 1 (10 kHz - 150 kHz)"
 Start
|
The start frequency of the test. For example 2 MHz.
|
| Stop
|
The stop frequency of the test. For example 10 MHz.
|
| Reference Level
|
The reference level set in an analyser, not used in a receiver
|
| Attenuation
|
The attenuation set in the receiver
|
| RBW
|
The RBW set in the receiver, see table with different bands for possible values
|
| Step size
|
The step size set in the receiver, see table with different bands for possible values
|
| Measure time
|
The measure time set in the receiver, see table with different bands for possible values
|
| Preamplifier
|
The preamplifier setting set in the receiver
|
| Traces
|
The type of trace set in the receiver, for MIL-STD-461 RE102 a peak detector is used
|
| Test Equipment
|
The equipment used for the measurement, see table with different bands for possible values
|
| Location type
|
Set this to "Antenna height, distance, polararization and angle"
|
| Max Height
|
The maximum height for the antenna tower, configuration is depending on how many positions should be measured
|
| Min Height
|
The minimal height for the antenna tower, configuration is depending on how many positions should be measured
|
| Steps
|
The number of height positions to measure, configuration is depending on how many positions should be measured
|
| Move during measurement
|
If the antenna tower can move during the measurement, not used during MIL-STD-461 RE102 measurement
|
| Optimize Height
|
Find the optimal emission around a certain height, not used during MIL-STD-461 RE102 measurement
|
| Distance
|
The used antenna distance, 1 Meter for MIL-STD-461 RE102
|
| Antenna Polarization
|
Which polarization is used, Vertical, Horizontal or Both, above 30 MHz both polarization should be tested
|
| Start Angle
|
The minimal turn table angle
|
| End Angle
|
The maximum turn table angle
|
| Steps
|
The number of angles to measure
|
| Turn during measurement
|
If the turn table can move during the measurement, not applicable for MIL-STD-461 RE102
|
| Optimize Angle
|
Find the optimal emission around a certain angle, not applicable for MIL-STD-461 RE102
|
| EUT Angle Offset
|
The offset of the EUT on the table, not applicable for MIL-STD-461 RE102
|
| Limit Lines
|
The applicable limit line can be added, in this case "MIL-STD-461G RE102 Ground Applications, Navy Mobile & Army"
|
| All peaks above x dB below the limit line
|
Which level above x dB below the limit line should detect peaks, no peaks should be measured in MIL-STD-461 RE102
|
| Peak detection
|
How many peaks should be detected automatically, no peaks should be measured for MIL-STD-461 RE102
|
| Final peak measurement
|
It is possible to perform a final measurement on a peak with a specific detector, no final peak measurement is needed for RE102
|
When all parameters are configured for the RE102 test, press Start Test to perform the emission measurement.
Review the test result[edit]
Once the test is finished, the results of this test is stored in the EUT file, and available as one of the performed Tests in the EUT file. Selecting the corresponding test result and pressing on Info will show the test results again.
Conclusion[edit]
The MIL-STD-461 RE102 test has to use multiple antennas and depending on the frequency band, different settings are configured. All these settings can be easily configured in a "Test Setup File" and tested with RadiMation®.
