Rohde & Schwarz ESW-K55E User manual

R&S®ESW-K55E and -K55R
Real-Time Spectrogram
User Manual
1179598202
Version 01
(;ÝÉà2)

This manual describes the following R&S®ESW models:
●R&S®ESW8 (1328.4100K08)
●R&S®ESW8 (1328.4100K09)
●R&S®ESW26 (1328.4100K26)
●R&S®ESW26 (1328.4100K27)
●R&S®ESW44 (1328.4100K44)
●R&S®ESW44 (1328.4100K45)
The contents of this manual correspond to firmware version 3.00 and higher.
The following firmware options are described:
●R&S®ESW-K55E (1351.1026.02)
●R&S®ESW-K55R (1351.1226.02)
© 2023 Rohde & Schwarz GmbH & Co. KG
Muehldorfstr. 15, 81671 Muenchen, Germany
Phone: [phone] - 0
Email: [email protected]
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.
Trade names are trademarks of the owners.
1179.5982.02 | Version 01 | R&S®ESW-K55E and -K55R
Throughout this manual, products from Rohde & Schwarz are indicated without the ® symbol , e.g. R&S®ESW is indicated as
R&S ESW.

Contents
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Contents
1 Preface.................................................................................................... 5
1.1 About this manual.........................................................................................................5
1.2 Documentation overview..............................................................................................5
1.3 Conventions used in the documentation....................................................................7
2 Welcome to the real-time spectrogram application............................9
2.1 Starting real-time spectrogram measurements......................................................... 9
2.2 Understanding the display information.................................................................... 10
3 Measurements and result displays.................................................... 13
3.1 Result display..............................................................................................................13
3.2 How to run a real-time spectrogram..........................................................................14
4 Configuration........................................................................................16
4.1 Notes about configuring real-time spectrogram measurements........................... 16
4.2 Configuration overview.............................................................................................. 17
4.3 General measurement settings..................................................................................18
4.4 Data input and output................................................................................................. 18
4.5 Frequency configuration............................................................................................ 21
4.6 Amplitude and vertical axis configuration................................................................24
4.7 Bandwidth configuration............................................................................................32
4.8 Sweep settings............................................................................................................ 35
4.9 Trigger.......................................................................................................................... 36
4.10 Display configuration................................................................................................. 39
4.11 Transducer...................................................................................................................39
5 Analysis................................................................................................ 40
5.1 Trace settings.............................................................................................................. 40
5.2 Marker settings............................................................................................................40
5.3 Line settings................................................................................................................ 40
6 Remote commands for real-time spectrogram measurements....... 41
6.1 Introduction................................................................................................................. 41
6.2 Common suffixes........................................................................................................ 46
6.3 Application selection.................................................................................................. 46

Contents
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6.4 Result display configuration......................................................................................50
6.5 Configuration...............................................................................................................58
6.6 Analysis....................................................................................................................... 79
List of commands................................................................................ 80
Index......................................................................................................82

Preface
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1 Preface
1.1 About this manual
This Real-Time Spectrogram User Manual provides all the information specific to the
application. All general instrument functions and settings common to all applications
and operating modes are described in the main R&S ESW User Manual.
The main focus in this manual is on the measurement results and the tasks required to
obtain them. The following topics are included:
●Welcome to the Real-Time Spectrogram Application
Introduction to and getting familiar with the application
●Measurements and Result Displays
Details on supported measurements and their result types
●Measurement Basics
Background information on basic terms and principles in the context of the mea-
surement
●Configuration + Analysis
A concise description of all functions and settings available to configure measure-
ments and analyze results with their corresponding remote control command
●Measurement Examples
Detailed measurement examples to guide you through typical measurement sce-
narios and allow you to try out the application immediately
●Remote Commands for Real-Time Spectrogram Measurements
Remote commands required to configure and perform Real-Time Spectrogram
measurements in a remote environment, sorted by tasks
(Commands required to set up the environment or to perform common tasks on the
instrument are provided in the main R&S ESW User Manual)
Programming examples demonstrate the use of many commands and can usually
be executed directly for test purposes
●List of remote commands
Alphabetical list of all remote commands described in the manual
●Index
1.2 Documentation overview
This section provides an overview of the R&S ESW user documentation. You find it on
the product page at:
www.rohde-schwarz.com/manual/esw
Documentation overview

Preface
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1.2.1 Getting started manual
Introduces the R&S ESW 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.
1.2.2 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.
●Manuals for (optional) firmware applications
Contains the description of the specific functions of a firmware application, includ-
ing remote control commands. Basic information on operating the R&S ESW is not
included.
The contents of the user manuals are available as help in the R&S ESW. 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.
1.2.3 Service manual
Describes the performance test for checking the rated specifications, module replace-
ment and repair, firmware update, troubleshooting and fault elimination, and contains
mechanical drawings and spare part lists.
The service manual is available for download for registered users on the global
Rohde & Schwarz information system (GLORIS):
https://gloris.rohde-schwarz.com
1.2.4 Instrument security procedures
Deals with security issues when working with the R&S ESW in secure areas. It is avail-
able for download on the Internet.
Documentation overview

Preface
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1.2.5 Basic safety instructions
Contains safety instructions, operating conditions and further important information.
The printed document is delivered with the instrument.
1.2.6 Data sheets and brochures
The data sheet contains the technical specifications of the R&S ESW. It also lists the
options 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/esw
1.2.7 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 open source acknowledgment document provides verbatim license texts of the
used open source software.
See www.rohde-schwarz.com/firmware/esw
1.2.8 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/esw
1.3 Conventions used in the documentation
1.3.1 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.
Conventions used in the documentation

Preface
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Convention Description
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.
1.3.2 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.
1.3.3 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.
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 real-time spectrogram application
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2 Welcome to the real-time spectrogram
application
The real-time spectrogram application provides functionality to perform real-time spec-
trogram measurements with the R&S ESW.
Requirements
●The R&S ESW-K55E requires an R&S ESW equipped with R&S ESW-B350 or -
B1000
●The R&S ESW-K55R requires an R&S ESW equipped with R&S ESW-B350R or -
B1000R
The application features real-time spectrogram measurements with two main result dis-
plays:
●Sweep
●Sweep spectrogram
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 ESW user manual. The latest version is available for download at
the product homepage http://www.rohde-schwarz.com/product/esw.
Installation
You can find detailed installation instructions in the R&S ESW getting started manual or
in the release notes.
2.1 Starting real-time spectrogram measurements
Real-time spectrogram measurements is a separate application on the R&S ESW.
To activate real-time spectrogram measurements
1. Select the [MODE] key.
A dialog box opens that contains all operating modes and applications currently
available on your R&S ESW.
2. Select the "Real-Time Spectrogram" item.
The R&S ESW opens a new channel for the application.
Starting real-time spectrogram measurements

Welcome to the real-time spectrogram application
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The measurement is started immediately with the default settings. It can be configured
in the real-time spectrogram configuration dialog box, which is displayed when you
select the "Overview" softkey from any menu.
Multiple Channels and sequencer function
When you activate an application, a new channel 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 channels that can be configured at the same time depends on the avail-
able memory on the instrument.
Only one measurement can be performed at any time, namely the one in the currently
active channel. However, in order 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 channels are updated in the tabs (as well as the
"MultiView") as the measurements are performed. Sequential operation itself is inde-
pendent of the currently displayed tab.
For details on the sequencer function see the R&S ESW user manual.
2.2 Understanding the display information
The following figure shows a measurement diagram during real-time spectrogram mea-
surements. All different information areas are labeled. They are explained in more
detail in the following sections.
Understanding the display information

Welcome to the real-time spectrogram application
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1 2 3
5 4
1 = Channel bar for firmware and measurement settings
2 = Window title bar with diagram-specific (trace) information
3 = Diagram area
4 = Instrument status bar with error messages and date/time display
5 = Diagram footer with diagram-specific information, depending on result display
Channel bar information
In the Real-Time Spectrogram application, the R&S ESW shows the following settings:
Table 2-1: Information displayed in the channel bar in the application for real-time spectrogram mea-
surements
Meas BW Measurement bandwidth
Att RF attenuation applied to input
Input Input toggle state
Meas Time Measurement time for data acquisition
Notch Notch filter state
PS Preselector state
Frequency Receiver Frequency
Window title bar
Each channel in the R&S ESW display can contain several windows. Each window can
display either a graph or a table as a result of the channel measurement. The window's
title bar indicates which type of evaluation is displayed.
Understanding the display information

Welcome to the real-time spectrogram application
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Information on the displayed traces is indicated in the window title bar.
Trace color
Trace number
Detector
Trace mode
For further information on the window title bar, see R&S ESW user manual.
Status bar information
Global instrument settings, the instrument status and any irregularities are indicated in
the status bar beneath the diagram.
Furthermore, the progress of the current operation is displayed in the status bar.
Understanding the display information

Measurements and result displays
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3 Measurements and result displays
The data that was measured by the R&S ESW can be evaluated using various different
methods. In the Real-Time Spectrogram application, multiple result displays can be
used simultaneously.
●Result display..........................................................................................................13
●How to run a real-time spectrogram........................................................................14
3.1 Result display
Access: "Overview" > "Display Config"
Or: [MEAS] > "Display Config"
The R&S ESW provides several result displays that show different aspects of the mea-
sured data.
Fast Access...................................................................................................................13
Marker Table................................................................................................................. 13
Notes.............................................................................................................................13
Preselector....................................................................................................................14
Sweep........................................................................................................................... 14
Sweep Spectrogram......................................................................................................14
Fast Access
By default, the Fast Access panel provides functionality to control the Reference Level
and the Tuned Frequency. For more information on how to change the functionality and
how to work with the Fast Access panel, refer to the R&S ESW user manual.
Remote command:
LAY:ADD? '1',RIGH,FACC
(See LAYout:ADD[:WINDow]? on page 51)
Marker Table
Provides functionality to display information for all active markers. For more information
on how to work with the Marker Table, refer to the R&S ESW user manual.
Remote command:
LAY:ADD? '1',RIGH,MTAB
(See LAYout:ADD[:WINDow]? on page 51)
Notes
Provides functionality to add comments or explanations to the current measurement.
For more information on how to work with the Notes panel, refer to the R&S ESW user
manual.
Remote command:
LAY:ADD? '1',RIGH,NOT
(See LAYout:ADD[:WINDow]? on page 51)
Result display

Measurements and result displays
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Preselector
Provides an overview of the active preselector filters. For more information on prese-
lector filters, refer to the R&S ESW user manual.
Remote command:
LAY:ADD? '1',RIGH,PRES
(See LAYout:ADD[:WINDow]? on page 51)
Sweep
Displays a frequency sweep of the input signal over a specified span.
Remote command:
LAY:ADD? '1',RIGH,SCAN
(See LAYout:ADD[:WINDow]? on page 51)
Sweep Spectrogram
Displays a spectrogram of a frequency sweep of the input signal over a specified span.
Remote command:
LAY:ADD? '1',RIGH,SCSG
(See LAYout:ADD[:WINDow]? on page 51)
3.2 How to run a real-time spectrogram
The following step-by-step instructions demonstrate how to perform a basic real-time
spectrogram measurement with the Real-Time Spectrogram application.
1. Press the [MODE] key on the front panel and select the "Real-Time Spectrogram"
application.
2. Select the "Overview" softkey to display the "Overview" for an Real-Time Spectro-
gram measurement.
How to run a real-time spectrogram

Measurements and result displays
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3. Select the "Amplitude" button to define the required level parameters.
4. Select the "Frequency" button to define the center frequency of the measurement.
5. Optionally, select the "Trigger" button to use an external trigger.
6. Select the "Bandwidth" button to configure the bandwidth parameters.
● "RBW": Define the resolution bandwidth in Hz
● "Sweep Time": Define how long data is captured for one line in the spectrogram
7. Select the "Analysis" button and then the "Spectrogram/Waterfall" tab to configure
the spectrogram.
● "History Depth": number of lines (frames) to be stored in the spectrogram (pos-
sibly for several consecutive measurements).
● Optionally, deactivate the "Time Stamp" option to refer to the individual lines
(frames) using an index number instead of the time they were captured.
● Optionally, select "Color Mapping" to change the colors with which the power
levels are represented in the spectrogram.
● Select "Clear Spectrogram" to start a new spectrogram display.
8. Press the "Sweep" key and set the "Sweep Count" to define the number of mea-
surements taken.
9. Press [RUN SINGLE] to start a measurement.
10. Scroll through the individual frames of the "Spectrogram":
a) Tap the "Spectrogram" window.
b) Press the [Sweep] key.
c) Select the "Select Frame" softkey and change the index number (negative
numbers from 0 downwards).
The "Real-Time Spectrogram" displays the stored spectrum for the selected frame.
11. Optionally, export the trace data of the spectrogram to a file.
a) Select the "Analysis" button in the "Overview".
b) In the "Traces" tab of the "Analysis" dialog box, switch to the "Trace Export"
tab.
c) From the "Specifics for" list, select the spectrogram display.
d) Select "Export Trace to ASCII File".
e) Define a file name and storage location and select "OK".
How to run a real-time spectrogram

Configuration
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4 Configuration
Access: [MODE] > "Real-Time Spectrogram"
When you activate the Real-Time Spectrogram application, a Real-Time Spectrogram
measurement for the input signal is started automatically with the default configuration.
It can be configured in the Real-Time Spectrogram "Overview" dialog box, which is dis-
played when you select the "Overview" softkey from any menu.
●Notes about configuring real-time spectrogram measurements............................. 16
●Configuration overview............................................................................................17
●General measurement settings...............................................................................18
●Data input and output..............................................................................................18
●Frequency configuration..........................................................................................21
●Amplitude and vertical axis configuration................................................................24
●Bandwidth configuration..........................................................................................32
●Sweep settings........................................................................................................35
●Trigger.....................................................................................................................36
●Display configuration...............................................................................................39
●Transducer.............................................................................................................. 39
4.1 Notes about configuring real-time spectrogram mea-
surements
In the real-time spectrogram application, the hardware uses different signal paths for
certain frequency ranges. A switch to another signal path occurs on certain frequen-
cies. The use of different signal paths prevent the R&S ESW from measuring in real-
time across these frequency borders. Therefore, the frequency settings have several
dependencies in the real-time spectrogram application.
Center frequency dependencies
For measurements in the vicinity of the frequency border, the R&S ESW tries to pre-
serve the span. If you enter a center frequency that is too close to a frequency border
to accomodate the span, the R&S ESW adjusts the center frequency to the next possi-
ble frequency and shows a corresponding message in the status bar.
The measurement still includes the frequency you have entered, but it is not possible
to use this frequency as the center frequency with the given span. If you decrease the
span, you can set a center frequency that is closer to the hardware border.
Span dependencies
Possible spans depend on the frequency range you are measuring in and the currently
selected measurement bandwidth. If you change the frequency range or the band-
width, the R&S ESW adjusts the span to the next possible value.
Note that due to the fact that the bandwidth also has an effect on the span, possible
spans can be different for a certain frequency.
Notes about configuring real-time spectrogram measurements

Configuration
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Example:
You are doing a measurement with a 9 kHz bandwidth, a center frequency of 75 MHz
and a span of 90 MHz.
If you set the center frequency to 60 MHz, the center frequency remains the same,
because a frequency border at 30 MHz in combination with 90 MHz span prevents a
60 MHz center frequency. If you decrease the span to 80 MHz, setting the center fre-
quency of 60 MHz is possible.
If you now set the center frequency to 25 MHz, the span will be adjusted to the largest
possible value in the frequency range below 30 MHz. In this case, you end up with a
new span of 29.85 MHz and a new center frequency of 15.075 MHz.
4.2 Configuration overview
Throughout the measurement configuration, an overview of the most important cur-
rently defined settings is provided in the "Overview". The "Overview" is displayed when
you select the "Overview" icon, which is available at the bottom of all softkey menus.
In addition to the main measurement settings, the "Overview" provides quick access to
the main settings dialog boxes. Thus, you can easily configure an entire EMI Real-
Time measurement channel from input over processing to output and analysis by step-
ping through the dialog boxes as indicated in the "Overview".
Preset Channel............................................................................................................. 17
Preset Channel
Select the "Preset Channel" button in the lower left-hand corner of the "Overview" to
restore all measurement settings in the current channel to their default values.
Configuration overview

Configuration
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Note: Do not confuse the "Preset Channel" button with the [Preset] key, which restores
the entire instrument to its default values and thus closes all channels on the
R&S ESW (except for the default channel)!
Remote command:
SYSTem:PRESet:CHANnel[:EXEC] on page 49
4.3 General measurement settings
Access: [MEAS CONFIG]
General measurement settings are settings that define the overall measurement proc-
ess.
Compliant
Turns CISPR compliant measurements on and off.
"On" Measurements compliant with CISPR 16-1-1. Preselector is on.
"Off" Measurements not compliant with CISPR 16-1-1. Preselector is off.
Remote command:
INPut<ip>:PRESelection:COMPliance[:STATe] on page 59
4.4 Data input and output
Access: "Overview" > "Input"
Access: "Overview" > "Output"
The R&S ESW can analyze signals from different input sources and provide various
types of output (such as video or trigger signals).
●Configuring the RF input......................................................................................... 18
●Configuring the preselector.....................................................................................20
●Configuring line impedance stabilization networks (LISN)......................................20
●Configuring additional outputs.................................................................................20
4.4.1 Configuring the RF input
Access: "Overview" > "Input / Frontend" > "Input Source" > "Radio Frequency"
The R&S ESW supports various signal input sources. The default input source is the
RF input.
Data input and output

Configuration
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Functions in the "Input" dialog box described elsewhere:
●"Input Selection" on page 19
The remote commands required to configure the RF input are described in Chap-
ter 6.5.1, "RF input", on page 58.
Input Selection.............................................................................................................. 19
Input Coupling...............................................................................................................19
Impedance.................................................................................................................... 20
Pulse Limiter................................................................................................................. 20
Input Selection
Selects the RF input connector you would like to use for a measurement.
Note that you cannot use both RF inputs simultaneously.
Remote command:
Global: INPut<ip>:TYPE on page 59
Input Coupling
The RF input of the R&S ESW can be coupled by alternating current (AC) or direct cur-
rent (DC).
Note that the "Input Coupling" feature is only available for input 2 when the pulse lim-
iter is turned off. When the pulse limiter is on, the input is always DC coupled.
AC coupling blocks any DC voltage from the input signal. AC coupling is activated by
default to prevent damage to the instrument. Very low frequencies in the input signal
can be distorted.
However, some specifications require DC coupling. In this case, you must protect the
instrument from damaging DC input voltages manually. For details, refer to the data
sheet.
Data input and output

Configuration
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Remote command:
INPut<ip>:COUPling on page 58
Impedance
For some measurements, the reference impedance for the measured levels of the
R&S ESW can be set to 50 Ω or 75 Ω.
Select 75 Ω if the 50 Ω input impedance is transformed to a higher impedance using a
75 Ω adapter of the RAZ type. (That corresponds to 25Ω in series to the input impe-
dance of the instrument.) The correction value in this case is 1.76 dB = 10 log (75Ω/
50Ω).
This value also affects the unit conversion.
Remote command:
INPut<ip>:IMPedance on page 58
Pulse Limiter
The pulse limiter, available for the second RF input, is a protection mechanism against
high level pulses or signals (which can damage the input mixer).
When you turn on the pulse limiter, the attenuation is always at least 10 dB. Attenua-
tion smaller than 10 dB is only available when you turn off the pulse limiter.
Remote command:
INPut<ip>:ATTenuation:LIMiter[:STATe] on page 59
4.4.2 Configuring the preselector
Access: "Overview" > "Input / Frontend" > "Preselector"
The preselector works similar to the preselector in the receiver application and can be
deactivated if needed.
For more information, refer to the user manual of the R&S ESW.
4.4.3 Configuring line impedance stabilization networks (LISN)
Access: "Overview" > "Output" > "LISN"
The R&S ESW supports several LISN models and provides functionality to control
these devices. The functionality is the same as in the receiver application.
For more information, refer to the user manual of the R&S ESW.
4.4.4 Configuring additional outputs
Access: "Overview" > "Output" > "Additional Outputs"
The R&S ESW provides several additional outputs. The functionality is the same as in
the receiver application.
Data input and output