Differential noise figure is compatible with the broadband and mmWave systems and, as with option 41, a receiver module greatly helps this effort by removing coupler losses (as loops are not available in the mmWave bands). Two such modules (like the 3744A-Rx) are required for most of the differential noise figure measurements, and receiver offset corrections can be applied to both receiver paths. In a 4-port setup, these receiver modules should be connected as ports 2 and 4, as these will be the only paths monitored for noise measurements. Port 1 can remain as a standard module, as it will be used for receiver and correlation calibrations. The overall calibration processes follow from what has been discussed.