Radiated Susceptibility Limits

The field level to which a device is subjected during Radiated Susceptibility testing is called the Limit.  The limit is typically specified as field strength over a range of frequencies.  The field level may be constant over the frequency range or may vary with frequency.  Limits are generally specified by the governing regulatory agency.

For example, at the time of this writing the European Union specifies in EN61000-4-3 that equipment subject to Level 3 requirements shall not be susceptible to field strength 10 V/m over the frequency range 80 MHz to 1 GHz.  Similarly, the US Military specifies in MIL-STD-461E that equipment installed internally aboard aircraft shall withstand 20 V/m from 2 MHz to 1 GHz, and 60 V/m from 1 GHz to 18 GHz.

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Interference Sources

Regulatory Agency Requirements