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With a PATH LOSS setting of 0 dB, a single path of the fading simulator introduces an insertion loss between 12 dB and 18 dB for the IQ signals applied (with Insertion Loss Setting Mode = NORMAL). This insertion loss provides a headroom if several paths are superimposed on one another and also for the statistical influences to which a path is exposed. In the LOW ACP mode, the insertion loss is reduced to approx. 6 dB to 12 dB. This may lead to the rare case that the clipping level is attained in the instrument.
In this case the IQ signals are limited to the maximum level (clipping). The insertion loss is automatically corrected in the SMIQ. The output power is kept constant.
Displays:
LEVEL: The rms value of the output signal is displayed.
PEP: The (theoretically possible) peak value is displayed. This value is attained if the clipping level is reached for both the I and the Q path. For signals with a high crest factor it is not likely that the PEP value is attained.
Due to the insertion loss introduced by the fading simulator, the maximum output power of the SMIQ is reduced by max. 18 dB.
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