Rohde & Schwarz R&S CMW-KN200 User manual

R&S®CMW-KN200
GSM BS Measurements
User Manual
User Manual
1177.5456.02 ─ 02
(;ÛÄÆ2)
Test & Measurement
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This user manual describes the R&S®CMW option
R&S®CMW-KN200 (GSM GPRS EDGE R6, BS TX measurement, downlink)
© 2015 Rohde & Schwarz GmbH & Co. KG
Mühldorfstr. 15, 81671 München, Germany
Phone: [phone] - 0
Fax: [phone]
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.
The following abbreviations are used throughout this manual: R&S®CMW is abbreviated as R&S CMW.
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Contents
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Contents
1 Preface.................................................................................................... 7
1.1 R&S CMW Models......................................................................................................... 7
1.2 How to Read Firmware Application Chapters............................................................ 7
1.2.1 General Description........................................................................................................ 8
1.2.2 Application Sheets.......................................................................................................... 8
1.2.3 GUI Reference................................................................................................................ 8
1.2.4 Programming Examples..................................................................................................8
1.2.5 Command Reference...................................................................................................... 9
2 What's New in this Revision................................................................10
3 General Description.............................................................................11
3.1 GSM TX Tests.............................................................................................................. 11
3.1.1 Test Setup.....................................................................................................................11
3.1.2 How to Measure a Downlink GSM Signal..................................................................... 11
3.1.3 Defining the Scope of the Measurement.......................................................................12
3.1.4 Detecting GSM Multislot Frames.................................................................................. 12
3.1.5 Configuring the Spectrum Measurement...................................................................... 14
3.1.6 Speed Considerations...................................................................................................14
3.2 GSM DL Signal Properties..........................................................................................14
3.3 GSM Frequency Bands and Channels...................................................................... 15
3.4 Burst Types................................................................................................................. 16
3.5 Limit Settings and Conformance Requirements......................................................17
3.5.1 Transmit Modulation Limits........................................................................................... 17
3.5.2 Avg. Burst Power Limits................................................................................................ 18
3.5.3 Power Templates.......................................................................................................... 20
3.5.4 Spectrum Limits............................................................................................................ 23
3.6 Measurement Results................................................................................................. 25
3.6.1 Overview....................................................................................................................... 25
3.6.2 Detailed Views: EVM, Magnitude Error, Phase Error and Spectrum............................ 26
3.6.3 Detailed Views: Power vs Time.....................................................................................28
3.6.4 Detailed Views: IQ Constellation Diagram.................................................................... 29
3.6.5 TX Measurement Scalar............................................................................................... 30
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3.6.6 Selecting and Modifying Views..................................................................................... 31
3.6.7 Using Markers............................................................................................................... 32
3.6.8 Common View Elements...............................................................................................32
4 GUI Reference...................................................................................... 34
4.1 Measurement Control................................................................................................. 34
4.2 Parameters and Settings............................................................................................ 34
4.2.1 Signal Routing and Analyzer Settings...........................................................................35
4.2.2 Common Measurement Control Settings...................................................................... 37
4.2.3 Modulation View Settings..............................................................................................40
4.2.4 Power vs. Time Settings............................................................................................... 42
4.2.5 Modulation Settings.......................................................................................................44
4.2.6 Spectrum Settings.........................................................................................................45
4.2.7 Trigger Settings.............................................................................................................47
4.2.8 Limits.............................................................................................................................50
4.2.9 Display Configuration.................................................................................................... 53
4.2.10 Generator Shortcut........................................................................................................53
4.2.11 Additional Softkeys and Hotkeys...................................................................................53
4.3 Measurement Results................................................................................................. 56
5 Programming........................................................................................60
5.1 General Examples....................................................................................................... 60
5.1.1 Specifying General Measurement Settings...................................................................60
5.1.2 Specifying Measurement-Specific Settings...................................................................61
5.1.3 Configuring the Trigger System.................................................................................... 61
5.1.4 Specifying Limits........................................................................................................... 62
5.1.5 Performing Single-Shot Measurements........................................................................ 64
5.1.6 Single-Shot and Continuous Measurements.................................................................64
5.1.7 Configuring a Spectrum Measurement......................................................................... 65
5.1.8 Selecting Specific Burst Types......................................................................................66
5.2 I/Q Constellation Diagram.......................................................................................... 66
6 Command Reference........................................................................... 68
6.1 Conventions and General Information......................................................................68
6.1.1 MEAS<i>....................................................................................................................... 68
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6.1.2 FETCh, READ and CALCulate Commands.................................................................. 68
6.1.3 Current and Statistical Results......................................................................................69
6.1.4 Values for RF Path Selection........................................................................................ 69
6.1.5 Keywords...................................................................................................................... 69
6.1.6 Reliability Indicator........................................................................................................ 70
6.2 General Measurement Settings................................................................................. 72
6.2.1 Signal Routing...............................................................................................................72
6.2.2 Analyzer Settings.......................................................................................................... 74
6.3 Multi Evaluation Measurement Commands..............................................................77
6.3.1 Measurement Control and States................................................................................. 77
6.3.2 Enabling Results and Views..........................................................................................79
6.3.3 Statistical Settings.........................................................................................................82
6.3.4 Measurement Settings.................................................................................................. 86
6.3.5 Power vs. Time Settings............................................................................................... 88
6.3.6 Modulation Settings.......................................................................................................89
6.3.7 Spectrum Modulation Settings...................................................................................... 89
6.3.8 Spectrum Switching Settings........................................................................................ 91
6.3.9 I/Q Constellation Settings..............................................................................................92
6.3.10 Trigger Settings.............................................................................................................93
6.3.11 Limits (GMSK Modulation)............................................................................................ 96
6.3.12 Limits (8-PSK Modulation).......................................................................................... 100
6.3.13 Limits (16-QAM Modulation)....................................................................................... 104
6.3.14 Limits (Power vs. Time)...............................................................................................108
6.3.15 Limits (Spectrum Modulation)..................................................................................... 114
6.3.16 Limits (Spectrum Switching)........................................................................................117
6.3.17 Modulation View Throughput Result........................................................................... 121
6.3.18 EVM Results (Traces)................................................................................................. 122
6.3.19 Magnitude Error Results (Traces)............................................................................... 122
6.3.20 Phase Error Results (Traces)......................................................................................123
6.3.21 Modulation Results (Single Values)............................................................................ 124
6.3.22 Power vs Time Results (Traces)................................................................................. 129
6.3.23 Power vs Time Results (Single Values)...................................................................... 130
6.3.24 Spectrum Modulation Results..................................................................................... 133
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6.3.25 Spectrum Switching Results....................................................................................... 135
6.3.26 I/Q Constellation Results (Traces).............................................................................. 137
List of Commands..............................................................................138
Index....................................................................................................142
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Preface
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1 Preface
The operation of the R&S CMW is described in several user manuals:
●The R&S CMW user manual describes the base software, common features of the
firmware applications and basic principles for manual operation and remote control.
There is a separate manual version for each R&S CMW model.
●Additional user manuals, like this document, describe the firmware applications.
There is only one version of these manuals for all R&S CMW models.
Rohde & Schwarz provides registered users a "CMW Customer Web" section on
GLORIS, the Global Rohde & Schwarz Information System: https://extranet.rohde-
schwarz.com. From this resource, you can download software updates, waveform
library updates and documentation updates, for example updates of this document.
1.1 R&S CMW Models
The R&S CMW software supports several instrument models. Depending on the
model, only a subset of the software packages and software options is allowed.
To check whether this document is relevant for your instrument model and which soft-
ware options are supported, refer to the preface of your model-specific base user man-
ual. The PDF filename of this manual starts with CMW<Model>_UserManual, for
example CMW500_UserManual.
1.2 How to Read Firmware Application Chapters
Each firmware application is described in a separate chapter. These chapters can be
read independently of each other. However, they are all organized as follows:
1. General Description
2. Application Sheets (optional)
3. GUI Reference
4. Programming Examples
5. Command Reference
The chapters "System Overview" and "Remote Control" in the R&S CMW user manual
provide additional important information independent of the individual firmware applica-
tions. The most important parts are referenced by the firmware application descrip-
tions.
How to Read Firmware Application Chapters
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1.2.1 General Description
This section provides a general description of the firmware application, independent of
a specific operation mode (manual or remote control). It gives a high-level introduction
to the capabilities of the firmware application. Background information related to the
network standard is given as far as it is directly related to administrable parameters.
For measurement applications a detailed description of measurement results and a
description of configurable limits is given, including the relation to conformance require-
ments defined in network standard specifications.
1.2.2 Application Sheets
This optional section provides short application examples for select issues and related
background information.
1.2.3 GUI Reference
The GUI reference describes the manual operation of the firmware application via the
Graphical User Interface (GUI).
The description of a configuration dialog usually starts with a screenshot presenting the
preset values of the parameters (sometimes preset values are modified to enable hid-
den parts of a dialog). Below the screenshot all shown parameters are described. For
each single parameter a link to the corresponding command description in the "Com-
mand Reference" is provided. Ranges for numeric parameters and reset values are
given there.
For measurement results links to the corresponding command descriptions are provi-
ded (commands to retrieve the results). The measurement results are described in
detail in the "General Description".
1.2.4 Programming Examples
The programming examples show how to control and configure the firmware applica-
tion via a remote-control program and how to retrieve measurement results. The exam-
ples consist of comprehensive command sequences. You can check just a single com-
mand of a sequence to get an example for the syntax of this single command. But you
can also consider an entire sequence showing the commands in the context of a com-
mand script, under consideration of dependencies and required orders of the com-
mands.
The command sequences are written with the intention to list most commands of the
firmware application. They do not show the fastest way for a given configuration task.
The fastest way would use many reset values and omit the corresponding commands.
The examples are referenced by the command descriptions of the "Command Refer-
ence".
How to Read Firmware Application Chapters
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1.2.5 Command Reference
The command reference provides information on the remote commands of the firm-
ware application. The commands are grouped according to their function.
Each command description indicates the syntax of the command header and of the
parameters. For input parameters the allowed ranges, reset values and default units
are listed, for returned values the expected ranges and default units. Most commands
have a command form and a query form. Exceptions are marked by "Setting only",
"Query only" or "Event". Furthermore a link to the "Programming Examples" is provided
and the first software version supporting the command is indicated.
How to Read Firmware Application Chapters
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What's New in this Revision
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2 What's New in this Revision
This document describes version 3.5.11 and later of the "GSM BS Measurements".
Compared to the initial software version 3.5.10, there are only editorial changes.
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General Description
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3 General Description
The GSM base station measurements provide quick and flexible TX tests on GSM
downlink signals. The tests cover the following BS transmitter properties:
●Transmitter output power over a wide range of timeslots
●Modulation accuracy (EVM, phase error, magnitude error and frequency error)
●Spectrum due to switching and due to modulation
●Off-carrier emissions vs. time
●I/Q constellation diagram
Many of the tests and conformance requirements are specified in 3GPP TS 51.021,
Base Station System (BSS) equipment specification; Radio aspects.
The GSM BS multi evaluation measurement requires option R&S CMW-KN200.
The following sections describe how to perform and configure the measurement.
●GSM TX Tests.........................................................................................................11
●GSM DL Signal Properties......................................................................................14
●GSM Frequency Bands and Channels....................................................................15
●Burst Types.............................................................................................................16
●Limit Settings and Conformance Requirements......................................................17
●Measurement Results............................................................................................. 25
3.1 GSM TX Tests
TX tests have many characteristics in common. The following sections describe these
characteristics and show how to perform TX tests.
3.1.1 Test Setup
The external RF signal source (base station, signal generator etc.) is connected to one
of the RF input connectors (RF COM) at the front panel of the R&S CMW. No addi-
tional cabling and no external trigger is needed.
The input level ranges of all RF COM connectors are identical.
See also: "RF Connectors" in the R&S CMW user manual, chapter "Getting Started"
3.1.2 How to Measure a Downlink GSM Signal
After connecting your GSM Base Station (BS) to the R&S CMW as shown above, you
have to adjust at least the following analyzer settings to the properties of the analyzed
DL GSM signal:
●The analyzer "Frequency"
GSM TX Tests
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●The "Expected Nominal Power" and (optional) a "User Margin" and "External
Attenuation".
Recommended values: "Expected Nominal Power" = average power of the BS sig-
nal; "User Margin" = + 5 dB (for 8-PSK-modulated bursts) and +7.5 dB (for 16-
QAM-modulated bursts).
The R&S CMW uses an RF power trigger and is able to synchronize to the incoming
bursts and decode the signal.
3.1.3 Defining the Scope of the Measurement
The GSM BS multi evaluation measurement is a multislot application: The R&S CMW
can measure up to 8 consecutive GSM slots (1 frame) and store the power results for
all slots.
Within this measurement interval, a single slot ("Measurement Slot") is selected for a
more detailed analysis. The measurement slot provides:
●The reference power and time reference (symbol no. 0) for the "Power vs. Time"
diagram.
●The results in all modulation and spectrum due to modulation diagrams (the spec-
trum due to switching results are measured over all slots).
●The statistical results in the detailed views of all modulation and spectrum dia-
grams.
If the interval of n measured slots is measured repeatedly, the R&S CMW can evaluate
the trace and slot statistics in consecutive intervals.
See also: "Statistical Settings" in the R&S CMW user manual, chapter "System Over-
view"
3.1.4 Detecting GSM Multislot Frames
With an active "Acquisition" trigger, the R&S CMW analyzes the RF input signal and
derives a frame trigger using information about the active slots. After frame detection,
the acquisition trigger events are repeated periodically according to the GSM frame
clock. TSC detection is performed continuously in order to compensate for a possible
drift. Two different acquisition trigger modes – "Gap" and "Pattern" – are available.
GSM TX Tests
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Gap Trigger
In the gap trigger mode the R&S CMW searches for a gap in the sequence of active
slots. A gap is a series of 1 to 3 inactive slots. The trigger event is generated at the
beginning of the first slot after the gap and is repeated periodically.
To use the gap trigger as shown above,
1. Feed the GSM downlink signal to the input connector and perform the necessary
analyzer settings, see How to Measure a Downlink GSM Signal .
2. Open the "GSM BS Measurement – Multi Evaluation Configuration" dialog.
3. Select "Trigger > Trigger Source: Acquisition", "Trigger > Acquisition > Mode:
Gap", "Trigger > Acquisition > Gap Length: 3".
4. Start the GSM BS Multi Evaluation measurement and observe the triggered frames
in the "Power vs. Time" diagram.
Pattern Trigger
In the pattern trigger mode the R&S CMW analyzes the modulation scheme of the
received bursts and searches for a predefined burst pattern. The trigger events are
generated at the beginning of the pattern and repeated according to the GSM frame
clock, even though the true burst pattern may have changed.
To use the pattern trigger as shown above,
1. Feed the GSM downlink signal to the input connector and perform the necessary
analyzer settings, see How to Measure a Downlink GSM Signal.
2. Open the "GSM BS Measurement – Multi Evaluation Configuration" dialog.
3. Select "Trigger > Trigger Source: Acquisition", "Trigger > Acquisition > Mode: Pat-
tern", "Trigger > Acquisition > Pattern: GMSK GMSK 8-PSK OFF 8-PSK OFF OFF
OFF".
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4. Start the GSM BS Multi Evaluation measurement and observe the triggered frames
in the "Power vs. Time" diagram.
3.1.5 Configuring the Spectrum Measurement
The spectrum measurements are performed in the "Measurement Slot". Compared to
the power vs. time and modulation measurements, spectrum measurements depend
on the following additional settings:
●The frequency offsets for the spectrum due to modulation and spectrum due to
switching measurements in the frequency domain.
●The evaluation area for the spectrum due to modulation measurement and the
peak hold mode for spectrum due to switching.
●The frequency offsets for the spectrum vs. time measurements.
●The spectrum vs. time measurements can slow down the measurement (see
Speed Considerations), so they can be enabled separately.
3.1.6 Speed Considerations
The following measurement settings provide additional results but can slow down the
measurement:
●Evaluation of the spectrum vs. time measurements
●Evaluation of the "AM-PM" delay for polar modulators
●Access burst search
The following settings improve the accuracy of the results but require additional pro-
cessing time:
●Measurement of 8-PSK or 16-QAM-modulated bursts in "Data Compensated" ref-
erence power mode.
3.2 GSM DL Signal Properties
The GSM physical channel uses a combination of frequency and time division multi-
plexing and is defined as a sequence of radio frequency channels and timeslots. The
basic system and physical channel parameters are listed below.
Table 3-1: Basic GSM parameters
Parameter Value
TDMA frame duration 60/13 ms ≈ 4.615 ms
Slot duration (8 slots per TDMA frame) 15/26 ms ≈ 576.9 μs
Symbol rate 270.833 ksymbol/s
GSM DL Signal Properties
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Parameter Value
Symbol duration 3.69 μs
(--> 156.25 symbols per timeslot)
Modulation schemes GMSK (1 bit per symbol)
8-PSK (3 bits per symbol)
16QAM (4 bits per symbol)
8-PSK channels (the so-called EDGE channels) and 16-QAM channels are used for
data transmission; only normal bursts are transmitted. The R&S CMW supports down-
link 16-QAM channels at normal symbol rate (EGPRS2-A channels). Hence, the sym-
bol rate for 8-PSK channels and 16-QAM channels is the same as for GMSK modula-
tion, which corresponds to a bit rate of 3 x 270.833 kbit/s and 4 x 270.833 kbit/s,
respectively.
The burst type analyzed by the R&S CMW is the normal burst. The reference power (0
dB line) is equal to the received transmitter carrier power, that is the average value of
the transmitter carrier power over the useful part of the burst as received by the
R&S CMW. The burst is fitted into the tolerance template such that the transition
between bit 13/14 of the training sequence corresponds to the center of the useful part
of the burst.
For further reference refer to the following standards:
●3GPP TS 45.002, physical channels and bursts
●3GPP TS 45.004, modulation formats
●3GPP TS 45.005, transmitter and receiver requirements
3.3 GSM Frequency Bands and Channels
The GSM frequency bands are defined in standard 3GPP TS 25.021. A band contains
a set of adjacent channels, each with a bandwidth of 200 kHz. The channel numbers
and the assignment between channel numbers and frequencies are band-specific.
In all frequency bands, the downlink frequencies are higher than the corresponding
uplink frequencies. The difference between downlink and uplink frequencies is termed
the duplex spacing; it is also band-specific.
The tables below give an overview all supported GSM bands with their channel num-
bers and the downlink and uplink center frequencies.
Band Channel Numbers Center Frequencies FDL in
MHz
Center Frequencies FUL in MHz
GSM4001) 259 to 340 460.6 to 495.0 450.6 to 485.0
GSMGT8002) 350 to 425 851.0 to 866.0 806.0 to 821.0
GSM8503) 128 to 251 869.2 to 893.8 824.2 to 848.8
GSM Frequency Bands and Channels
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Band Channel Numbers Center Frequencies FDL in
MHz
Center Frequencies FUL in MHz
GSM900
(P-GSM900)
(R-GSM900)
(E-GSM900)
0 to 124
940 to 974
975 to 1023
935.0 to 959.8
918.2 to 925.0
925.2 to 934.8
890.0 to 914.8
873.2 to 880.0
880.2 to 889.8
GSM18004) 512 to 885 1805.2 to 1879.8 1710.2 to 1784.8
GSM19005) 512 to 810 1930.2 to 1989.8 1850.2 to 1909.8
1) This R&S CMW band comprises the bands GSM450 and GSM480 from the stand-
ard.
2) This R&S CMW band corresponds to band T-GSM810 from the standard.
3) This R&S CMW band corresponds to the bands GSM850 and MXM850 from the
standard.
4) This R&S CMW band corresponds to the band DCS1800 from the standard.
5) This R&S CMW band corresponds to the bands PCS1900 and MXM1900 from the
standard.
3.4 Burst Types
The GSM physical channel is a sequence of timeslots, each of which is divided into
156.25 symbol periods; see GSM DL Signal Properties. A burst represents the physical
content of a timeslot. Standard 3GPP TS 45.002 defines the different burst types
together with their bit structure. The GSM BS multi evaluation measurement supports
all specified downlink burst types.
GMSK-modulated normal burst
The GSMK-modulated normal burst is used for data transmission on the traffic channel
and on the control channels (except the RACH, PRACH and CPRACH).
The normal burst contains two 57-bit long data fields for the transmission of the user
information. The training sequence (TSC) in the center is flanked by two "stealing flag"
bits (S1); each of them is set to 0. The 2 times 3 tail bits at the beginning and at the
end of the burst are all set to 0, the 8.25-bit guard period at the end is transmission-
free.
8-PSK-modulated normal burst
An EDGE burst is an 8-PSK-modulated normal burst; see GSM DL Signal Properties.
EDGE bursts are used for data transmission at higher data rates. Due to the higher-
Burst Types
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order modulation scheme, the bit content of all fields is tripled. The "stealing flag" bits
are not present. All tail bits are set to 1. The length of the guard period is 24.75 bits.
16-QAM-modulated normal burst
To further increase the data rate, EDGE Evolution introduces 16-QAM-modulated nor-
mal bursts; see GSM DL Signal Properties. The burst structure is equal to the 8-PSK-
modulated normal burst, however, the bit content is multiplied by a factor of 4/3: The
burst contains (12 + 232 + 104 + 232 + 36) bits.
Access burst
The access burst is used by mobile stations for initial random access to the network
and for handover. In packet data mode, it is also possible to use access bursts for the
transmission of CONTROL_ACK_TYPE messages. Compared to a normal burst, the
access burst has an extended guard period (EGuard, 68.25 symbols instead of 8.25
symbols) whereas the useful duration is shortened by 60 symbols. Access bursts are
always GMSK-modulated
3.5 Limit Settings and Conformance Requirements
Conformance requirements are specified in Base Station System (BSS) equipment
specification in 3GPP TS 51.021, section 6, "Transmitter" and in the related specifica-
tions quoted therein.
The following sections give an overview of the R&S CMW limit settings and the related
test requirements.
●Transmit Modulation Limits..................................................................................... 17
●Avg. Burst Power Limits..........................................................................................18
●Power Templates.................................................................................................... 20
●Spectrum Limits...................................................................................................... 23
3.5.1 Transmit Modulation Limits
A poor modulation accuracy of the base transceiver station (BTS) increases the trans-
mission errors in the downlink channel of the GSM network. The frequency error and
the phase error are the critical quantities to assess the modulation accuracy of a BTS.
For GMSK modulation 3GPP defines that the frequency error, measured at various
BTS output powers and frequencies, shall not exceed 0.05 ppm (0.1 ppm for pico BTS
and multicarrier BTS). In addition, the RMS phase error, measured after adjustment for
the effect of the frequency error and averaged over all samples in the useful part of the
Limit Settings and Conformance Requirements
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burst, shall not exceed 5 deg. The peak phase error shall not exceed 20 deg. At each
channel and BTS output power, the measurement shall be repeated with a statistic
count ≥ 200 bursts.
For higher order modulation 3GPP defines the RMS EVM at various criteria, see 3GPP
TS 51.021, section 6.2.4, conformance requirement (for example RMS EVM values,
measured after any active element and excluding the effect of passive combining
equipment shall not exceed 7 % for 8-PSK and 5 % for 16-QAM under normal condi-
tions and normal symbol rate). The peak EVM shall not exceed 22 % and the EVM 95th
percentile shall not exceed 11 %. In addition the I/Q offset shall be better than -35 dB.
The frequency error shall not exceed 0.05 ppm (0.1 ppm for pico BTS and multicarrier
BTS).
The specified limits can be set in the configuration dialog, along with limits for the other
measured quantities (for reference information refer to Modulation).
3.5.2 Avg. Burst Power Limits
Dynamic power control is essential to ensure stable transmission and an efficient radio
resource management within the system. Generally speaking, an output power of the
BTS that is too low decreases the coverage area while an excess output power may
cause interference to other channels or systems. Both effects decrease the system
capacity.
GSM base stations are divided into different power classes according to their maxi-
mum output power as listed in the following tables (see 3GPP TS 45.005, section
4.1.2).
Limit Settings and Conformance Requirements
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Table 3-2: Normal BTS power classes except multicarrier
TRX
power
class
Maximum output power for GSM 400, GSM
900, ER-GSM 900, GSM 850, MXM 850, GSM
700
Maximum output power for DCS 1800, PCS
1900, MXM 1900
1
2
3
4
5
6
7
8
320 ≦ P in W < 640
160 ≦ P in W < 320
80 ≦ P in W < 160
40 ≦ P in W < 80
20 ≦ P in W < 40
10 ≦ P in W < 20
5 ≦ P in W < 10
2,5 ≦ P in W < 5
20 ≦ P in W < 40
10 ≦ P in W < 20
5 ≦ P in W < 10
2,5 ≦ P in W < 5
-
-
-
-
Table 3-3: Micro and pico BTS power classes
TRX
power
class
Maximum output power for GSM 400, GSM
900, ER-GSM 900, GSM 850, MXM 850, GSM
700
Maximum output power for DCS 1800, PCS
1900, MXM 1900
M1
M2
M3
P1
19 < P in dBm ≦ 24
14 < P in dBm ≦ 19
9 < P in dBm ≦ 14
13 < P in dBm ≦ 20
27 < P in dBm ≦ 32
22 < P in dBm ≦ 27
17 < P in dBm ≦ 22
16 < P in dBm ≦ 23
Table 3-4: Multicarrier BTS power classes
TRX power class Total output power limit per antenna for all
bands
Wide Area
Medium Range *
Local Area *
no limitation
38 dBm
24 dBm
* not applicable for MXM 850 and MXM 1900
The TRX power class is defined by the highest single carrier output power capability
for any modulation.
Static power step (N)
The output power may be reduced from the maximum level in six or more steps of 2 dB
with an accuracy of ±1 dB.
The static power step N has the range from the highest static power level to Nmax inclu-
sive, where
●The Highest Static Power Level corresponds to the maximum single carrier output
power declared by the manufacturer. For multicarrier BTS, the Highest Static
Power Level corresponds to maximum output power per carrier for each supported
number of carriers declared by the manufacturer.
●The Lowest Static Power Level is defined as the Highest Static Power Level
reduced by Nmax power steps, where the number of power steps can be different
for each supported modulation.
Limit Settings and Conformance Requirements
深圳德标仪器 135-1095-0799

General Description
R&S®CMW-KN200
20User Manual 1177.5456.02 ─ 02
In addition, the actual absolute output power at each static RF power step (N) shall be
2*N dB below the absolute output power at static RF power step 0. The static RF
power step 0 shall be the actual output power according to the TRX power class. For
exceptions see 3GPP, TS 45.005, section 4.1.2 c.
Downlink RF power control
The actual absolute output power for each supported modulation at each power control
level shall be 2*Y dB below the maximum BTS output power for the modulation with
the highest output power capability. Y is the sum of the number of steps below highest
static power level for the modulation with the highest output power capability. For
exceptions see 3GPP, TS 45.005, section 4.1.2 c.
According to the GSM standard, the tolerances for the BTS average burst power are
listed in the following table.
Table 3-5: Tolerances
Normal conditions Extreme conditions
Maximum output power ±2.0 dB ±2.5 dB
Output power at each static power
step
±3.0 dB ±4.0 dB
Output power at each power con-
trol level
±3.0 dB ±4.0 dB
The limits can be set in the configuration dialog (for reference information refer to Avg.
Burst Power).
During the guard periods between any two active timeslots, the power must not be
larger than 3 dB above the nominal burst power (dBc value); see also Time mask of a
multislot configuration.
3.5.3 Power Templates
The GSM power templates specify the dynamic structure (power/time relationship) of
the transmitted GSM bursts. The burst is subdivided into different time intervals (areas)
with specified upper and lower transmitter output power. The entire power template is
Limit Settings and Conformance Requirements
深圳德标仪器 135-1095-0799