Radio Frequency Susceptibility (Radiated and Conducted)
RTCA DO-160 – Section 20.0 – Radio Frequency Susceptibility (Radiated and Conducted)
These tests determine whether equipment will operate within performance specifications when the equipment and its interconnecting wiring are exposed to a level of RF modulated power, either by a radiated RF field or by injection probe induction onto the power lines and interface circuit wiring.
Two test procedures are used:
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From 10 kHz to 400 MHz, the equipment under test (EUT) is subjected to RF signals coupled by means of injection probes into its cable bundles, and
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for frequencies between 100 MHz and the upper frequency limit, the EUT is subjected to radiated RF fields. There is an intentional overlap of the tests from 100 to 400 MHz.
Radiated susceptibility tests from 100 MHz to 18 GHz may be conducted using methods and materials as described within Section 20.5 (Anechoic Chamber Method) or Section 20.6 (Reverberation Chamber Method). The choice of methods is at the discretion of the applicant.
Equipment with special signal, frequency, modulation or bandpass characteristics may require test variations as specified by the applicable performance standards.
The result of these tests can be used to:
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Determine equipment response to various RF threats such as HIRF, T-PEDs, and
installed system’s emissions, and to
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Permit categories to be assigned defining the conducted and radiated RF test levels of
the equipment
These tests are sufficient to obtain environmental qualification for radio frequency susceptibility of the equipment. Additional tests may be necessary to certify the installation of systems in an aircraft dependent on the functions performed.
Categories B, D, F, G, L, M and O provide test levels which directly relate to the high intensity radiated field (HIRF) external field environments for systems with highest criticality as specified in the HIRF regulations.
Category R provides test levels for equipment when: a) Bench testing is allowed to meet the HIRF for systems with high criticality as specified in the HIRF regulations, and b) Showing backdoor Transmitting-Portable Electronic Device (T-PED) tolerance.
Category S provides a minimum test level where aircraft effects from the external electromagnetic environment are minor and where interference free operation on the aircraft is desirable but not required. This category may also be representative of the internal EMI environment from aircraft equipment.
Category T provides test levels for equipment when bench testing is allowed to meet the HIRF for systems with moderate criticality as specified in the HIRF regulations. This category may also be representative of the internal EMI environment from aircraft equipment.
Categories W and Y a) Bench testing supporting compliance to HIRF Special Conditions, and provide test levels for: b) Showing backdoor T-PED tolerance
Category Q indicates tests conducted at test limits or with modulations other than those specified in these procedures.
