Rohde & Schwarz R&S FSP Series, Operating Manual

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Operating Manual 1164.4556.12 - 06 4.281
R&S FSP Instrument Functions
LO/IF ports for external mixers - Option R&S FSP-B21
If unwanted mixer products represented at frequencies which slightly differ from
each other occur in the test sweep and reference sweep, the two mixer products
from the test sweep and the reference sweep are displayed by the same sweep
point. They will not be detected as unwanted mixer products by
AUTO ID and there-
fore not be blanked out. Illustration of this follows:
Fig. 4.38 Screen A: Unwanted mixer product not detected by AUTO ID
Screen B: Unwanted mixer product not detected by AUTO ID and examined with a small
span using SIGNAL ID
An input signal consisting of a large number of spectral components is shown in Fig.
4.38 , screen A. Unwanted mixer products are blanked out with AUTO ID . If a signal
identified as real is examined at approx. 29.615 GHz (see marker in Fig. 4.38 ) with a
reduced span using SIGNAL ID (see Fig. 4.38 , screen B), it can be seen that the
mixer products represented in the test sweep and reference sweep differ by approx.
16.5 MHz in their frequency. For the span of 13.4 GHz set in
Fig. 4.38 , screen A, a
frequency range of 21,4 MHz is displayed by one sweep point (selection 625 sweep
points).
Very small spans should therefore be selected to ensure correct signal identification
by means of
AUTO ID .
R e f 0 d B m
1 A P
C L R W R
1 A P
C L R W R
2 A P
C L R W R
R e f - 2 0 d B m
1 0 M H z / C e n t e r 2 9 . 6 1 5 3 8 4 6 2 G H z S p a n 1 0 0 M H z
R B W 2 M H z
V B W 5 M H z
S W T 2 0 m s
1 . 3 4 G H z / C e n t e r 3 3 . 2 G H z S p a n 1 3 . 4 G H z
R B W 3 M H z
V B W 1 0 M H z
S W T 8 0 m s
E X T
A
B
- 9 0
- 8 0
- 7 0
- 6 0
- 5 0
- 4 0
- 3 0
- 2 0
- 1 0
- 1 1 0
- 1 0 0
- 9 0
- 8 0
- 7 0
- 6 0
- 5 0
- 4 0
- 3 0
1
M a r k e r 1 [ T 1 ]
- 3 6 . 8 4 d B m
2 9 . 6 0 8 8 1 4 1 0 3 G H z
2
D e l t a 2 [ T 2 ]
- 1 8 . 4 7 d B
1 6 . 5 0 6 4 1 0 2 5 6 M H z
1
M a r k e r 1 [ T 1 ]
- 5 5 . 5 6 d B m
2 9 . 6 1 5 3 8 4 6 1 5 G H z