SWRA004A
High-Band Cascaded: Noise Figure
Control state: 111001
SEE APPENDIX A: TEST BENCH SETUPS
Test setup Figure 22
The cascaded Noise Figure (NF) is measured at the EVM Low Band IF output port, J21. The measurement is performed using an HP8970B Noise Figure Meter. The IF output of the mixer is converted from differential to single ended using a transformer balun. The noise figure meter requires a special setup and calibration since the RF source and receive frequencies are different.
Set up the noise figure meter as follows:
1)Special Function 1.4 sets the noise figure meter to measure variable IF and fixed LO frequencies.
2)The IF start, stop, and step size frequencies are set to 100MHz, 120MHz, and 5MHz respectively.
3)Set the smoothing to 16 or above.
4)Ensure that the Excess Noise Ratio (ENR) Table on the Noise Source head in use is entered on the NF meter.
a)On the front panel, press the ENR button.
b)Check the ENR value by pressing the Enter button or enter the ENR value for each frequency.
c)After entering the ENR for the desired frequency, press the Frequency button on the front panel to exit.
5)To calibrate the NF Meter:
a)Connect the Noise Source directly to the NF meter; press the calibration button twice.
b)Next, press the Noise Figure and Gain Button. The corrected LED just above the button should be lit.
c)Calibration is complete. Enter the desired IF frequency to measure.
Next, the external equipment Loss is considered (RF cable,
Transmission line, filter and circulator).
6)The losses are entered in the Noise Figure Meter by using special function 34.x.
TRF1500 Integrated | 43 |
