Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Instrument Functions
LO/IF ports for external mixers - Option R&S FSP-B21
4.286 Operating Manual 1164.4556.12 - 06
Fig. 4.41 Spectrum at the multiplier output recorded with an external mixer
6. Level correction with average value
If an average value is to be taken into account instead of the frequency-dependent
level correction, enter the following parameters for the selected band in the
SELECT BAND table:
➢
Enter the table with
[
FREQUENCY : EXTERNAL MIXER : SELECT BAND} dB ]:
➢
Enter the average of the conversion loss into the field AVG CONV LOSS:
{conversion loss}
dB ]
➢
Enter the type of mixer (in this example 2-port mixer) into the field PORTS.
➢
Enter the permissible harmonic (in this example even, since a double-diode
mixer is used) into the field EVEN/ODD HARMONICS:
By pressing ENTER a list box will be opened to select the permissible
harmonic.
The entered average value is taken into account for the spectrum display
irrespective of the frequency. The precision that can be obtained depends on
the frequency response of the mixer. With this type of level correction
measurements can be easily performed at single frequencies.
7. Taking into account the cable loss in the IF path
On performing level correction, the conversion loss of the mixer and also the
insertion loss a
0
of the cable used to tap off the IF signal are to be taken into
account. This additional loss is frequency-dependent.
➢
Determine the insertion of the cable at the intermediate frequency f
IF
= 404.4
MHz.
➢
For level correction with average value, add the cable insertion loss to the
average conversion loss.
1 A P
C L R W R
A
R B W 3 M H z
S W T 5 0 m s
* V B W 1 M H z
R e f - 2 0 d B m
C e n t e r 5 6 G H z S p a n 8 G H z 8 0 0 M H z /
E X T
- 1 2 0
- 1 1 0
- 1 0 0
- 9 0
- 8 0
- 7 0
- 6 0
- 5 0
- 4 0
- 3 0
- 2 0
1
M a r k e r 1 [ T 1 ]
- 3 6 . 0 7 d B m
5 8 . 0 1 2 8 2 0 5 1 3 G H z