am supression
The setup is very simple.
An RF Test set (let’s say CMU200) and a Signal Generator (let’s say ESG or SMIQ with framed GSM modulation) are routed through a power splitter to the input of your mobile.
The mobile is in loop-back with RF Test Set (CMU200), receiving a mid-band channel fo (level –99dBm at antenna connector, that is 3dB above reference sensitivity).
The frequency of the Signal Generator is set to any frequency fg = fo > 6MHz, but shall be inside of the receive band, and shall be an integer of channel spacing (200kHz). The level of the Signal Generator at antenna connector shall be as in the spec table (beware to take into account the splitter loss).
Is specifying that you can use a notch filter (notch frequency = fo, between Signal Generator and splitter) to minimize the co-channel interferer that can affect your test. You have to take into account the notch attenuation at Signal Generator frequency (fg).