ETTC'2003 - SEE

At equipment level
EMC TEST PROGRAM
When an equipment has been previously qualified for another project and will be used for a new
program without modification, then only those tests, or parts of tests, for which the equipment has not
yet demonstrated compliance are performed, provided that full visibility of the previous test
specifications and test results is available. When an equipment is modified to meet requirements, then
the degree of re-testing and any additional testing is defined.
The test requirements for units, based on the allowed limits defined in the EMC part of the equipment
environment test requirements, include: conducted emission (sine and transient), conducted
susceptibility (sine and transient), radiated emission, radiated susceptibility and ESD. These tests are
made as early as possible in the program on the first available model that is electrically representative
of the flight unit. Tests on later models are not normally performed unless the equipment design is
changed or EMC modifications have to be made.
At repeater level
The radiated tests are of the "sniff" (radiated emission located at connection/unit level) & "snort"
(radiated susceptibility located at connection/unit level) type, and as such they provide an easy
possibility of tracing the RF level to its source. The tests are performed at the worst case in receive and
transmit bands. These tests are not intended to duplicate, but rather to confirm and complement the
equipment tests already performed in order to check that no RF connection performed on the
communication module during the AIT sequence presents abnormal RF leakage level.
At system level
The purpose is to verify safety margins in conducted and radiated mode, the compatibility with the
launcher & the launch facility and the RF auto-compatibility.
Conducted mode
The aim of these conducted emissions and conducted susceptibility tests is to verify that the different
functional chains of the satellite are mutually compatible for the conducted mode with sufficient safety
margins in all the spacecraft operating modes. It is demonstrated an operating margin of at least:
- Main power buses: 6 dB
- Pyrotechnic devices: 20 dB
Radiated mode
The radiated emissions by the satellite in launch configuration shall be below the limits defined by the
launch authority. These limits are dependant on the launch site and launch vehicle.
The radiated susceptibility test goal is to check that the satellite continues to operate in accordance
with the relevant system performance specification when it is submitted to a narrow-band and/or
broadband electric fields in the launcher site & vehicle frequency range. The field strength is
dependant on the used launcher.
RF auto-compatibility
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