Rohde & Schwarz R&S FSP Series, Operating Manual

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R&S FSP Getting Started
Introduction
2.2 Operating Manual 1164.4556.12 - 06
2.1 Introduction
This chapter explains how to operate the R&S FSP using typical measurements as
examples.
The basic operating steps such as selecting the menus and setting parameters are
described in the Quick Start Guide, chapter 4, "Basic Operation". Furthermore, the
screen structure and displayed function indicators are explained in this chapter.
Chapter “Instrument Functions” describes all the menus and R&S FSP functions.
All of the following examples are based on the standard settings of the R&S FSP.
These are set with the
PRESET key. A complete listing of the standard settings can
be found in chapter “Instrument Functions” , section “R&S FSP Initial Configuration –
PRESET Key” on page 4.5 . Examples of more basic character are provided in the
Quick Start Guide, chapter 5, as an introduction.
2.2 Measuring the Spectra of Complex Signals
2.2.1 Intermodulation Measurements
If several signals are applied to a DUT with non-linear characteristics, unwanted
mixing products are generated – mostly by active components such as amplifiers or
mixers. The products created by 3
rd order intermodulation are particularly trouble-
some as they have frequencies close to the useful signals and, compared with other
products, are closest in level to the useful signals. The fundamental wave of one sig-
nal is mixed with the 2
nd harmonic of the other signal.
f
s1
= 2 × f
u1
– f
u2
(6)
f
s2
= 2 × f
u2
– f
u1
(7)
where f
s1
and f
s2
are the frequencies of the intermodulation products and f
u1
and f
u2
the frequencies of the useful signals.
The following diagram shows the position of the intermodulation products in the fre-
quency domain.
Fig. 2.8 3
rd
order intermodulation products
Frequency
P
u2
P
u1
P
s1
P
s2
∆
f
∆
f
∆
f
a
D3
Level
f
s1
f
u1
f
u2
f
s2