Rohde&Schwarz ZNL User manual

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R&S®ZNL
Analog Demodulation Mode
(SA Option R&S®FPL1K7)
User Manual
1178599502
Version 13
(;ÜÉí2)
This manual applies to the following R&S®ZNL models with firmware version 1.71 and higher:
R&S®ZNL3, 5 kHz to 3 GHz, 2 ports, N(f) connectors, order no. 1323.0012K03
R&S®ZNL4, 5 kHz to 4.5 GHz, 2 ports, N(f) connectors, order no. 1323.0012K04
R&S®ZNL6, 5 kHz to 6 GHz, 2 ports, N(f) connectors, order no. 1323.0012K06
R&S®ZNL14, 5 kHz to 14 GHz, 2 ports, N(f) connectors, order no. 1323.0012K14
Serial numbers 101200 and higher
R&S®ZNL20, 5 kHz to 20 GHz, 2 ports, 3.5 mm (m) connectors, order no. 1323.0012K20
Serial numbers 101200 and higher
The following firmware options are described:
R&S®ZNL3-B1 Spectrum Analysis (1323.1802.02)
R&S®ZNL4-B1 Spectrum Analysis (1303.8099.02)
R&S®ZNL6-B1 Spectrum Analysis (1323.2067.02)
R&S®ZNL14-B1 Spectrum Analysis (1303.8082.02)
R&S®ZNL20-B1 Spectrum Analysis (1303.8101.02)
R&S FPL1-K7 Analog Demodulation AM/FM/PM (1323.1731.02)
© 2023 Rohde & Schwarz GmbH & Co. KG
Muehldorfstr. 15, 81671 Muenchen, Germany
Phone: +49 89 41 29 - 0
Internet: www.rohde-schwarz.com
Subject to change – data without tolerance limits is not binding.
R&S® is a registered trademark of Rohde & Schwarz GmbH & Co. KG.
All other trademarks are the properties of their respective owners.
1178.5995.02 | Version 13 | R&S®ZNL
Throughout this manual, products from Rohde & Schwarz are indicated without the ® symbol, e.g. R&S®ZNL is indicated as
R&S ZNL.
Contents
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3User Manual 1178.5995.02 ─ 13
Contents
1 Preface.................................................................................................... 5
1.1 Documentation overview..............................................................................................5
1.2 Conventions used in the documentation....................................................................7
2 Welcome to the R&S FPL1-K7 AM/FM/PM Modulation Analysis
application.............................................................................................. 9
2.1 Starting AM/FM/PM Modulation Analysis....................................................................9
2.2 Understanding the display information.................................................................... 10
3 Measurements and result displays.................................................... 13
4 Measurement basics............................................................................24
4.1 Demodulation process............................................................................................... 24
4.2 Demodulation bandwidth........................................................................................... 26
4.3 Sample rate and demodulation bandwidth...............................................................27
4.4 AF triggers................................................................................................................... 28
4.5 AF filters.......................................................................................................................29
4.6 Time domain zoom......................................................................................................29
5 Configuration........................................................................................31
5.1 Configuration overview.............................................................................................. 31
5.2 Configuration according to standards......................................................................33
5.3 Input and frontend settings........................................................................................35
5.4 Trigger configuration.................................................................................................. 42
5.5 Data acquisition.......................................................................................................... 45
5.6 Demodulation display.................................................................................................50
5.7 Demodulation.............................................................................................................. 50
5.8 Output settings............................................................................................................69
5.9 Adjusting settings automatically...............................................................................69
6 Analysis................................................................................................ 73
6.1 Trace settings.............................................................................................................. 73
6.2 Spectrogram settings................................................................................................. 76
6.3 Trace / data export configuration.............................................................................. 81
Contents
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4User Manual 1178.5995.02 ─ 13
6.4 Working with markers in the R&S FPL1-K7 AM/FM/PM Modulation Analysis appli-
cation............................................................................................................................84
7 I/Q data import and export................................................................ 104
8 How to perform measurements in the R&S FPL1-K7 AM/FM/PM
Modulation Analysis application...................................................... 105
8.1 How to export trace data and numerical results.................................................... 106
9 Measurement example: demodulating an FM signal...................... 107
10 Optimizing and troubleshooting the measurement........................ 112
11 Remote commands for AM/FM/PM Modulation Analysis............... 113
11.1 Introduction............................................................................................................... 114
11.2 Common suffixes...................................................................................................... 119
11.3 Activating analog modulation analysis...................................................................119
11.4 Configuring the measurement................................................................................. 122
11.5 Capturing data and performing sweeps................................................................. 167
11.6 Configuring the result display................................................................................. 170
11.7 Retrieving results......................................................................................................178
11.8 Analyzing results...................................................................................................... 190
11.9 Importing and exporting I/Q data and results........................................................ 264
11.10 Deprecated commands.............................................................................................265
11.11 Programming example............................................................................................. 266
Annex.................................................................................................. 269
A Predefined standards and settings.................................................. 269
List of commands (analog demodulation mode)............................ 271
Index....................................................................................................280
Preface
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5User Manual 1178.5995.02 ─ 13
1 Preface
This chapter provides safety-related information, an overview of the user documenta-
tion and the conventions used in the documentation.
1.1 Documentation overview
This section provides an overview of the R&S ZNL user documentation. Unless speci-
fied otherwise, you find the documents at:
www.rohde-schwarz.com/manual/ZNL or www.rohde-schwarz.com/manual/ZNLE.
1.1.1 Getting started manual
Introduces the R&S ZNL and describes how to set up and start working with the prod-
uct. Includes basic operations, typical measurement examples, and general informa-
tion, e.g. safety instructions, etc.
A printed version is delivered with the instrument. A PDF version is available for down-
load on the Internet.
1.1.2 User manuals and help
Separate user manuals are provided for the base unit and the firmware applications:
Base unit manual
Contains the description of all instrument modes and functions. It also provides an
introduction to remote control, a complete description of the remote control com-
mands with programming examples, and information on maintenance, instrument
interfaces and error messages. Includes the contents of the getting started manual.
Firmware application manual
Contains the description of the specific functions of a firmware application, includ-
ing remote control commands. Basic information on operating the R&S ZNL is not
included.
The contents of the user manuals are available as help in the R&S ZNL. The help
offers quick, context-sensitive access to the complete information for the base unit and
the firmware applications.
All user manuals are also available for download or for immediate display on the Inter-
net.
1.1.3 Service manual
Describes the performance test for checking compliance with rated specifications, firm-
ware update, troubleshooting, adjustments, installing options and maintenance.
Documentation overview
Preface
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6User Manual 1178.5995.02 ─ 13
The service manual is available for registered users on the global Rohde & Schwarz
information system (GLORIS):
https://gloris.rohde-schwarz.com
1.1.4 Instrument security procedures
Deals with security issues when working with the R&S ZNL in secure areas. It is availa-
ble for download on the Internet.
1.1.5 Printed safety instructions
Provides safety information in many languages. The printed document is delivered with
the product.
1.1.6 Data sheets and brochures
The data sheet contains the technical specifications of the R&S ZNL. It also lists the
firmware applications and their order numbers, and optional accessories.
The brochure provides an overview of the instrument and deals with the specific char-
acteristics.
See www.rohde-schwarz.com/brochure-datasheet/ZNL or www.rohde-schwarz.com/
brochure-datasheet/ZNLE.
1.1.7 Release notes and open source acknowledgment (OSA)
The release notes list new features, improvements and known issues of the current
firmware version, and describe the firmware installation.
The software makes use of several valuable open source software packages. An open-
source acknowledgment document provides verbatim license texts of the used open
source software.
See www.rohde-schwarz.com/firmware/ZNL or www.rohde-schwarz.com/firmware/
ZNLE.
1.1.8 Application notes, application cards, white papers, etc.
These documents deal with special applications or background information on particu-
lar topics.
See www.rohde-schwarz.com/application/ZNL or www.rohde-schwarz.com/application/
ZNLE.
Documentation overview
Preface
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7User Manual 1178.5995.02 ─ 13
1.1.9 Calibration certificate
The document is available on https://gloris.rohde-schwarz.com/calcert. You need the
device ID of your instrument, which you can find on a label on the rear panel.
1.2 Conventions used in the documentation
1.2.1 Typographical conventions
The following text markers are used throughout this documentation:
Convention Description
"Graphical user interface ele-
ments"
All names of graphical user interface elements on the screen, such as
dialog boxes, menus, options, buttons, and softkeys are enclosed by
quotation marks.
[Keys] Key and knob names are enclosed by square brackets.
Filenames, commands,
program code
Filenames, commands, coding samples and screen output are distin-
guished by their font.
Input Input to be entered by the user is displayed in italics.
Links Links that you can click are displayed in blue font.
"References" References to other parts of the documentation are enclosed by quota-
tion marks.
1.2.2 Conventions for procedure descriptions
When operating the instrument, several alternative methods may be available to per-
form the same task. In this case, the procedure using the touchscreen is described.
Any elements that can be activated by touching can also be clicked using an addition-
ally connected mouse. The alternative procedure using the keys on the instrument or
the on-screen keyboard is only described if it deviates from the standard operating pro-
cedures.
The term "select" may refer to any of the described methods, i.e. using a finger on the
touchscreen, a mouse pointer in the display, or a key on the instrument or on a key-
board.
1.2.3 Notes on screenshots
When describing the functions of the product, we use sample screenshots. These
screenshots are meant to illustrate as many as possible of the provided functions and
possible interdependencies between parameters. The shown values may not represent
realistic usage scenarios.
Conventions used in the documentation
Preface
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8User Manual 1178.5995.02 ─ 13
The screenshots usually show a fully equipped product, that is: with all options instal-
led. Thus, some functions shown in the screenshots may not be available in your par-
ticular product configuration.
Conventions used in the documentation
Welcome to the R&S FPL1-K7 AM/FM/PM Modulation Analysis application
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9User Manual 1178.5995.02 ─ 13
2 Welcome to the R&S FPL1-K7 AM/FM/PM
Modulation Analysis application
The R&S FPL1-K7 AM/FM/PM Modulation Analysis application option converts the
R&S ZNL into an analog modulation analyzer for amplitude-, frequency- or phase-
modulated signals. It measures not only characteristics of the useful modulation, but
also factors such as residual FM or synchronous modulation.
The R&S FPL1-K7 AM/FM/PM Modulation Analysis application features:
AM, FM, and PM demodulation, with various result displays:
Modulation signal versus time
Spectrum of the modulation signal (FFT)
RF signal power versus time
Spectrum of the RF signal
Determining maximum, minimum and average or current values in parallel over a
selected number of measurements
Maximum accuracy and temperature stability due to sampling (digitization) already
at the IF and digital down-conversion to the baseband (I/Q)
Error-free AM to FM conversion and vice versa, without deviation errors, frequency
response or frequency drift at DC coupling
Relative demodulation, in relation to a user-defined or measured reference value
Availability of the R&S FPL1-K7 AM/FM/PM Modulation Analysis application
The R&S FPL1-K7 AM/FM/PM Modulation Analysis application becomes available
when you equip the R&S ZNLxx with the optional spectrum analyzer hardware option
R&S ZNLxx-B1 and the optional AM/FM/PM Modulation Analysis firmware (R&S FPL1-
K7).
For the R&S ZNLE and for R&S ZNL14 and R&S ZNL20 with serial numbers below
101200, these options are not available.
This user manual contains a description of the functionality that the application pro-
vides, including remote control operation.
All functions not discussed in this manual are the same as in the base unit and are
described in the R&S ZNL User Manual. The latest version is available for download at
the product homepage http://www.rohde-schwarz.com/product/ZNL.
2.1 Starting AM/FM/PM Modulation Analysis
AM/FM/PM Modulation Analysis is a separate application on the R&S ZNL.
To activate AM/FM/PM Modulation Analysis
1. Select the [MODE] key.
Starting AM/FM/PM Modulation Analysis
Welcome to the R&S FPL1-K7 AM/FM/PM Modulation Analysis application
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A dialog box opens that contains all operating modes and applications currently
available on your R&S ZNL.
2. Select the "Analog Demod" item.
The R&S ZNL opens a new channel setup for the application for analog modulation
analysis.
The measurement is started immediately with the default settings. It can be configured
in the analog modulation analysis "Overview" dialog box, which is displayed when you
select the "Overview" softkey from any menu (see Chapter 5.1, "Configuration over-
view", on page 31).
Multiple Channel Setups and Sequencer Function
When you activate an application, a new channel setup is created which determines
the measurement settings for that application ("Channel"). The same application can
be activated with different measurement settings by creating several "Channel"s for the
same application.
The number of channel setups that can be configured at the same time depends on the
available memory on the instrument.
Only one measurement can be performed at any time, namely the one in the currently
active channel setup. However, to perform the configured measurements consecu-
tively, a Sequencer function is provided.
If activated, the measurements configured in the currently defined "Channel"s are per-
formed one after the other in the order of the tabs. The currently active measurement is
indicated by a symbol in the tab label.
The result displays of the individual channel setups are updated in the tabs (as well as
the "MultiView" ) as the measurements are performed. Sequential operation itself is
independent of the currently displayed tab.
For details on the Sequencer function, see the R&S ZNL User Manual.
2.2 Understanding the display information
The following figure shows a measurement diagram during analog modulation analy-
sis. All different information areas are labeled. They are explained in more detail in the
following sections.
Understanding the display information
Welcome to the R&S FPL1-K7 AM/FM/PM Modulation Analysis application
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1
3
5
4
2
1 = Channel Setup bar for firmware and measurement settings
2 = Diagram area
3 = Window title bar with diagram-specific (trace) information
4 = Instrument status bar with error messages and date/time display
5 = Diagram footer with diagram-specific information, depending on result display
Channel Setup bar information
In the Analog Modulation Analysis application, the R&S ZNL shows the following set-
tings:
Table 2-1: Information displayed in the channel setup bar in the application for analog modulation
analysis
Ref Level Reference level
Offset Reference level offset
AQT Measurement time for data acquisition.
RBW Resolution bandwidth
DBW Demodulation bandwidth
Freq Center frequency for the RF signal
Window title bar information
For each diagram, the header provides the following information:
1 2 3
4
5 6 7 8 9
Figure 2-1: Window title bar information in the application for analog modulation analysis
Understanding the display information
Welcome to the R&S FPL1-K7 AM/FM/PM Modulation Analysis application
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12User Manual 1178.5995.02 ─ 13
1 = Window number
2 = Window type
3 = Trace color
4 = Trace number
5 = Detector
6 = Trace mode
7 = Reference value (at the defined reference position)
8 = AF coupling (AC/DC), only in AF time domains, if applicable
9 = Results are selected for demodulation output
Diagram footer information
The diagram footer (beneath the diagram) contains the following information, depend-
ing on the evaluation:
"RF Spectrum"
CF: Center frequency
of input signal
Sweep points Span: measured span
RF Time domain
CF: Center frequency
of input signal
Sweep points Time per division
AF Spectrum
AF CF: center fre-
quency of demodula-
ted signal
Sweep points AF Span: evaluated span
AF Time domain
CF: Center frequency
of input signal
Sweep points Time per division
For most modes, the number of sweep points shown in the display are indicated in the
diagram footer. In zoom mode, the (rounded) number of currently displayed points are
indicated.
Status bar information
Global instrument settings, the instrument status and any irregularities are indicated in
the status bar beneath the diagram.
Understanding the display information
Measurements and result displays
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3 Measurements and result displays
Access: "Overview" > "Display Config"
Or: [MEAS] > "Display Config"
The data that was measured by the R&S ZNL can be evaluated using various different
methods. In the Analog Modulation Analysis application, up to six evaluation methods
can be displayed simultaneously in separate windows. The results can be displayed as
absolute deviations or relative to a reference value or level.
The abbreviation "AF" (for Audio Frequency) refers to the demodulated AM, FM or PM
signal.
Basis for evaluation
All evaluations are based on the I/Q data set acquired during the measurement. The
spectrum of the modulated signal to be evaluated is determined by the demodulation
bandwidth. However, it can be restricted to a limited span ( "AF Span" ) if only part of
the signal is of interest. Furthermore, the time base for evaluations in the time domain
can be restricted to analyze a smaller extract in more detail, see Chapter 4.6, "Time
domain zoom", on page 29.
AM Time Domain ..........................................................................................................13
FM Time Domain ..........................................................................................................14
PM Time Domain ..........................................................................................................15
AM Spectrum ............................................................................................................... 16
FM Spectrum ................................................................................................................17
PM Spectrum ............................................................................................................... 18
RF Time Domain .......................................................................................................... 19
RF Spectrum ................................................................................................................20
Result Summary ...........................................................................................................21
Marker Table ................................................................................................................ 23
Marker Peak List .......................................................................................................... 23
AM Time Domain
Displays the modulation depth of the demodulated AM signal (in %) versus time.
Measurements and result displays
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Optionally, the settling time can be evaluated and displayed, see Chapter 5.7.7, "Set-
tling time", on page 67.
Remote command:
LAY:ADD? '1',RIGH,'XTIM:AM:REL'
(See LAYout:ADD[:WINDow]? on page 171)
FM Time Domain
Displays the frequency spectrum of the demodulated FM signal versus time.
Measurements and result displays
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Optionally, the settling time can be evaluated and displayed, see Chapter 5.7.7, "Set-
tling time", on page 67.
Remote command:
LAY:ADD? '1',RIGH,'XTIM:FM'
(See LAYout:ADD[:WINDow]? on page 171)
PM Time Domain
Displays the phase deviations of the demodulated PM signal (in rad or °) versus time.
Measurements and result displays
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Optionally, the settling time can be evaluated and displayed, see Chapter 5.7.7, "Set-
tling time", on page 67.
Remote command:
LAY:ADD? '1',RIGH,'XTIM:PM'
(See LAYout:ADD[:WINDow]? on page 171)
AM Spectrum
Displays the modulation depth of the demodulated AM signal (in % or dB) versus AF
span. The spectrum is calculated from the demodulated AM signal in the time domain
via FFT.
Measurements and result displays
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Remote command:
LAY:ADD? '1',RIGH,'XTIMe:AM:REL:AFSPectrum1'
(see LAYout:ADD[:WINDow]? on page 171)
FM Spectrum
Displays the frequency deviations of the demodulated FM signal (in Hz or dB) versus
AF span. The spectrum is calculated from the demodulated AM signal in the time
domain via FFT.
Measurements and result displays
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18User Manual 1178.5995.02 ─ 13
Remote command:
LAY:ADD? '1',RIGH,'XTIMe:FM:AFSPectrum1'
(see LAYout:ADD[:WINDow]? on page 171)
PM Spectrum
Displays the phase deviations of the demodulated PM signal (in rad, ° or dB) versus
AF span. The spectrum is calculated from the demodulated AM signal in the time
domain via FFT.
Measurements and result displays
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19User Manual 1178.5995.02 ─ 13
Remote command:
LAY:ADD? '1',RIGH,'XTIMe:PM:AFSPectrum1'
(see LAYout:ADD[:WINDow]? on page 171)
RF Time Domain
Displays the RF power of the input signal versus time. The level values represent the
magnitude of the I/Q data set.
Measurements and result displays
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20User Manual 1178.5995.02 ─ 13
Optionally, the settling time can be evaluated and displayed, see Chapter 5.7.7, "Set-
tling time", on page 67.
Remote command:
LAY:ADD? '1',RIGH,'XTIM:AM'
(see LAYout:ADD[:WINDow]? on page 171)
RF Spectrum
Displays the spectrum of the input signal. In contrast to the Spectrum application, the
frequency values are determined using FFT from the recorded I/Q data set.
/