field shows a selection for the PXB (supported instrument) or an External Fader (unsupported instrument).All instruments supported by software are shown in the tree window. But for some tests, there may be an additional instrument selection within the test setting window that is not supported by the software (not shown in the tree window). An example of this situation is in the LTE Clause 8 test setting window, where the Fading Simulator field shows a selection for the PXB (supported instrument) or an External Fader (unsupported instrument).
When an unsupported instrument is selected, there are additional manual test settings that must be performed. The unsupported instrument must be configured in accordance with the standards to perform its function
The external fader is a Fading Simulator selection for the Clause 8 tests. Even though it is a selection within the software, the external fader is not supported by the software and therefore not controlled by the software. But the signal generators used in conjunction with the external fader, and identified (connected) in the Hardware Connections and Settings node are controlled by the software. The following list shows the requirements to use an external fader:
the external fader, in addition to providing fading for all signals, must also provide the following:
the AWGN (this is indicated in the software by the AWGN section being grayed out)
the MIMO configuration
the propagation condition
some external fader settings must match those of the software's channel configuration (see the tutorials)
each waveform must use a separate signal generator
the signal generators used must be the ones listed in the requirements topic for Clause 8 tests
the external fader must be able to adjust the SNR to compensate for the signal generator's increased power level of 3 dB and 6 dB for Rx antenna setups of 2x and 4x respectively
This increased power level is in addition to the software's displayed signal generator power level.
the State checkbox must be checked for all signals and the Override Settings checkbox unchecked to download valid signal generator test signals in accordance with the 3GPP standards
