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ISO-11451-2:2005 Narrow Band RF Immunity

8. June 2015 18:47 by streng in
NB RF Immunity for EV should be carried out per IEC 61980-1 Annex B - Radiated RF Field 20 MHz - 2 G

NB RF Immunity for EV should be carried out per IEC 61980-1 Annex B - Radiated RF Field 20 MHz - 2 GHz @ 30V/m using the test setup per ISO-11451-2:2005.

The test is performed in ALSE chamber, the aim being to create an indoor electromagnetic compatibility testing facility that simulates open field testing.

The position or positions of the vehicle relative to the antenna or TLS (Transmission Line System) are specified in the EMC test plan.

The radiating elements of the field-generating device is no closer than 0,5 m to any absorbing material and no closer than 1,5 m to the wall of the shielded enclosure.

No part of the radiating antenna is closer than 0,5 m to the outer body surface of the vehicle. The phase centre of the antenna is separated by at least 2 m horizontally from the reference point. No part of an antenna's radiating elements is closer than 0,25 m to the floor. There is no absorber material in the direct path between the transmitting antenna and the DUT.

No part of a TLS, with the exception of the ground plane, is closer than 0,5 m to any part of the vehicle. The TLS radiating element or elements is separated by at least 1 m vertically from the reference point. The TLS is extend centrally over at least 75 % of the length of the vehicle.

The test is performed using the substitution method, which is based on the use of forward power as the reference parameter used for field calibration and during testing.

The field calibration is done without the vehicle present. The specific test level (field) shall be calibrated periodically, using an unmodulated sinusoidal wave, by recording the forward power required to produce a specific field strength (measured with a field probe) for each test frequency. The field strength is calibrated for vertical and horizontal polarizations.

* at a height of (1 ± 0,05) m above the shielded enclosure floor for vehicles with a roof height =< 3 m;
* at a height of (2 ± 0,05) m for vehicles with roof heights > 3 m.

* at heights of 0,5 m, 0,8 m, 1 m and 1,2 m, for vehicles with a roof height =< 3 m;
* at heights of 1,2 m, 1,5 m, 1,8 m and 2,1 m, for vehicles with a roof height > 3 m.