There are three places to enter offsets in N1912A==> Channel off set, freq dep offset and display offset.
1. I have a network consisting of RF cables , directional coupler and attenuator between PA output and N1921A power head. I have 2 port S parameter files of this network from 1800 MHz to 2000 MHz in 1 MHz spacing. Can I use this file as Freq Dep offset? The examples in the manual shows frequency vs some percentage in the freq dep offset table. Could you please explain this?
2. Suppose my network between PA output and N1921A has a loss of 52 dB at 1805 MHz. I enter 52 dB as channel offset and 1805 MHz as freq, this value of 52 dB will be used as offset, right.
3. For the case 2 above, suppose I have another number in the Freq Dep offset table along with the 52 dB as channel offset. Will the total offset be sum of these two?
4. It has been mentioned that “Note that when selected, frequency dependent offset corrections are applied IN ADDITION to any correction for sensor frequency response”. Could you please explain the concept of “Sensor Frequency Response offset”.
Thanks..
Leyo Joseph
Hi,
See below the answer for your questions:
Answer #1: Yes, you may use your S parameter filem but you may need to change the unit to percentage (%). For your case, you may want to use the channel offset, in order to enter the offset in dB. But, this you will have to change the offset every time the frequnecy is changed. Alternatively, you can convert the loss in dB to %.
Answer #2: Yes, you are right.
Answer #3: Yes, the total offset will be the sum of both.
Answer #4: Each sensor will have their own frequency response/characteristc. For example, the calibration factor of the sensor is varies across the freqeuncy.