Rohde & Schwarz CMW-KM750 User manual

R&S®CMW-KM750/-KM751
TD-SCDMA Firmware Applications
User Manual
User Manual
(;×îÔ2)
1173.9670.02 ─ 05
Test & Measurement

This user manual describes the following R&S®CMW options:
●R&S®CMW-KM750 (TD-SCDMA, TX measurement, uplink)
●R&S®CMW-KM751 (TD-SCDMA enhancement, TX measurement, uplink)
© 2012 Rohde & Schwarz GmbH & Co. KG
Muehldorfstr. 15, 81671 Munich, Germany
Phone: [phone] - 0
Fax: [phone]
E-mail: [email protected]
Internet: http://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.

Contents
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Contents
1Preface....................................................................................................7
1.1 How to Read Firmware Application Chapters............................................................7
1.1.1 General Description........................................................................................................7
1.1.2 Application Sheets..........................................................................................................7
1.1.3 GUI Reference................................................................................................................8
1.1.4 Programming Examples..................................................................................................8
1.1.5 Command Reference......................................................................................................8
2What's New in this Revision..................................................................9
3General Description.............................................................................10
3.1 TD-SCDMA TX Tests...................................................................................................10
3.1.1 Test Setup.....................................................................................................................10
3.1.2 Measuring an Uplink TD-SCDMA Signal......................................................................11
3.1.3 Defining the Scope of the Measurement.......................................................................11
3.1.4 Trigger Modes...............................................................................................................12
3.2 TD-SCDMA RX Tests...................................................................................................12
3.2.1 Test Setup.....................................................................................................................13
3.2.2 Performing a TD-SCDMA RX Test................................................................................13
3.3 Multi Evaluation List Mode.........................................................................................14
3.4 TD-SCDMA Signal Properties....................................................................................17
3.4.1 Frames and Timeslots...................................................................................................17
3.4.2 Channelization for CDMA..............................................................................................19
3.5 Limit Settings and Conformance Requirements......................................................20
3.5.1 Transmit Modulation Limits...........................................................................................20
3.5.2 Power Templates..........................................................................................................21
3.5.3 ACLR Limits..................................................................................................................22
3.5.4 Spectrum Emission Mask..............................................................................................23
3.6 Measurement Results.................................................................................................25
3.6.1 Overview.......................................................................................................................25
3.6.2 Detailed Views: Modulation, CDP and CDE, Power vs Time........................................26
3.6.3 Detailed Views: ACLR...................................................................................................28
3.6.4 Detailed Views: Spectrum Emission Mask....................................................................29

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3.6.5 Mod. Scalar and BER....................................................................................................30
3.6.6 Selecting and Modifying Views.....................................................................................31
3.6.7 Using Markers...............................................................................................................32
3.6.8 Common View Elements...............................................................................................32
4GUI 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 UE Signal Info...............................................................................................................37
4.2.3 Measurement Control Settings......................................................................................39
4.2.4 Trigger Settings.............................................................................................................44
4.2.5 Limit Settings.................................................................................................................46
4.3 Measurement Results.................................................................................................47
5Programming........................................................................................50
5.1 General Examples.......................................................................................................50
5.1.1 Specifying General Measurement Settings...................................................................50
5.1.2 Specifying Required Settings........................................................................................51
5.1.3 Specifying Additional Measurement-Specific Settings..................................................52
5.1.4 Configuring the Trigger System....................................................................................52
5.1.5 Specifying Limits...........................................................................................................53
5.1.6 Performing Single-Shot Measurements........................................................................53
5.1.7 Single-Shot and Continuous Measurements.................................................................55
5.2 Using the TD-SCDMA List Mode................................................................................55
5.2.1 Specifying Global Measurement Settings.....................................................................56
5.2.2 Specifying List Mode Settings.......................................................................................56
5.2.3 Performing Single-Shot Measurements........................................................................56
5.2.4 Retrieving Single Results for All Segments...................................................................57
6Command Reference...........................................................................59
6.1 Conventions and General Information......................................................................59
6.1.1 MEAS<i>.......................................................................................................................59
6.1.2 FETCh, READ and CALCulate Commands..................................................................59
6.1.3 Current and Statistical Results......................................................................................60

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6.1.4 Reliability Indicator........................................................................................................60
6.2 General Measurement Settings.................................................................................62
6.2.1 Signal Routing...............................................................................................................63
6.2.2 Analyzer Settings..........................................................................................................64
6.2.3 UE Signal Info...............................................................................................................66
6.3 Multi Evaluation Measurement Commands..............................................................73
6.3.1 Measurement Control and States.................................................................................73
6.3.2 Enabling Results and Views..........................................................................................75
6.3.3 Measurement Parameters.............................................................................................81
6.3.4 List Mode Settings.........................................................................................................87
6.3.5 Trigger Settings.............................................................................................................92
6.3.6 Limits (Modulation)........................................................................................................95
6.3.7 Limits (Power vs. Time).................................................................................................98
6.3.8 Limits (Spectrum ACLR).............................................................................................100
6.3.9 Limits (Spectrum Emission)........................................................................................102
6.3.10 EVM Results (Traces).................................................................................................103
6.3.11 Magnitude Error Results (Traces)...............................................................................105
6.3.12 Phase Error Results (Traces)......................................................................................107
6.3.13 CDP Results (Traces).................................................................................................109
6.3.14 CDE Results (Traces).................................................................................................111
6.3.15 Power vs Time Results (Traces + Limits)....................................................................114
6.3.16 Spectrum Emission Results (Traces)..........................................................................116
6.3.17 Modulation Results (Single Values)............................................................................118
6.3.18 Spectrum Results (Single Values)..............................................................................122
6.3.19 RX Results (Single Values).........................................................................................123
6.3.20 List Mode Results (One Segment)..............................................................................123
6.3.21 List Mode Results (All Segments, One Result)...........................................................129
6.3.22 List Mode Results (All Segments, Result Groups)......................................................139
List of Commands..............................................................................144
Index....................................................................................................152

Contents
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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.
●Additional user manuals, like this document, describe the firmware applications.
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, e.g. updates of this document.
1.1 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 descriptions.
1.1.1 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 mea-
surement applications a detailed description of measurement results and a description
of configurable limits is given, including the relation to conformance requirements defined
in network standard specifications.
1.1.2 Application Sheets
This optional section provides short application examples for select issues and related
background information.
How to Read Firmware Application Chapters

Preface
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1.1.3 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 hidden
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 "Command
Reference" is provided. Ranges for numeric parameters and reset values are given there.
For measurement results links to the corresponding command descriptions are provided
(commands to retrieve the results). The measurement results are described in detail in
the "General Description".
1.1.4 Programming Examples
The programming examples show how to control and configure the firmware application
via a remote-control program and how to retrieve measurement results. The examples
consist of comprehensive command sequences. You can check just a single command
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 command script,
under consideration of dependencies and required orders of the commands.
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".
1.1.5 Command Reference
The command reference provides information on the remote commands of the firmware
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

What's New in this Revision
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2 What's New in this Revision
This revision describes version 3.0.30 and later of the "TD-SCDMA Measurement" firm-
ware application. Compared to version 3.0.20 it provides the following new features:
●List mode enhancements, see Multi Evaluation List Mode:
– Increased maximum number of segments to 500
– Increased maximum number of subframes to 1600
Software Version
To check your R&S CMW software version, open the "Setup" dialog and click "HW/SW
Equipment". The initial software version for each remote control command is quoted in
the reference description.

General Description
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3 General Description
The "TD-SCDMA measurement" firmware application (option R&S CMW-KM750) pro-
vides quick and flexible TX tests on TD-SCDMA uplink signals and an RX test (Bit Error
Rate and Block Error Ratio).
Option R&S CMW-KM750 allows to measure QPSK modulated signals only. To measure
16-QAM modulated signals, option R&S CMW-KM751 is required additionally.
The tests cover the following UE transmitter properties:
●UE output power over a wide range of slots
●Modulation accuracy
●Spectrum emissions
●Code Domain Power (CDP) and Code Domain Error (CDE)
Many of the tests and conformance requirements are specified in 3GPP TS 34.122,
"Universal Mobile Telecommunications System (UMTS); Terminal conformance specifi-
cation; Radio transmission and reception (TDD)".
The following sections describe how to perform and configure the measurement.
●TD-SCDMA TX Tests..............................................................................................10
●TD-SCDMA RX Tests.............................................................................................12
●Multi Evaluation List Mode......................................................................................14
●TD-SCDMA Signal Properties.................................................................................17
●Limit Settings and Conformance Requirements......................................................20
●Measurement Results.............................................................................................25
3.1 TD-SCDMA 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 (mobile 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 additional
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"
TD-SCDMA TX Tests

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Fig. 3-1: Connecting an RF transmitter to the instrument
3.1.2 Measuring an Uplink TD-SCDMA Signal
After connecting your TD-SCDMA UE to the R&S CMW you have to adjust the following
analyzer settings to the properties of the analyzed UL TD-SCDMA signal:
●The analyzer "Frequency"
●The "Expected Nominal Power" and (optional) a "User Margin" and "External Attenu-
ation". Recommended values: "Expected Nominal Power" = peak power of the UE
signal over the entire measurement range; "User Margin" = 0 dB (the smallest pos-
sible value ensures maximum dynamic range).
For synchronization to the received signal and proper decoding, the "UE Signal Info"
settings in the configuration dialog must be in accordance with the measured signal. In
particular, ensure that the following parameters match up:
●The "First Active Uplink Slot Number"
●The position of the duplex "Switching Point"
●The "Scrambling Code" and the "User Number"
●The "Modulation Type"
The R&S CMW can auto-detect the spreading factors and channelization codes of the
channels.
With matching "UE Signal Info" settings, the R&S CMW is able to decode the signal and
determine its slot timing. No additional measurement trigger is required. Non-matching
"UE Signal Info" settings generally result in large EVM results.
3.1.3 Defining the Scope of the Measurement
The R&S CMW can measure up to 16 consecutive TD-SCDMA subframes (112 slots) in
a single measurement cycle and store the measurement results for each slot. The total
number of slots per measurement cycle is termed the "Measurement Length".
Within this measurement interval, two individual slots are selected for a more detailed
analysis:
●The "Preselected Slot" is used for single slot measurements, e.g. to measure the
Adjacent Channel Leakage power Ratio (ACLR), the spectrum emissions and single
slot modulation measurements (vs. chip results).
Any uplink slot within the measurement interval can be selected.
TD-SCDMA TX Tests

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●For the multislot measurements statistical results are measured for all slots and are
displayed for one slot at a time, the "Scalar Slot". Statistical results are relevant in
particular if the "Measurement Length" is measured repeatedly.
Any slot within the measurement interval can be selected.
Fig. 3-2: Preselected Slot and Scalar Slot
The "Preselected Slot" and the "Scalar Slot" are completely independent from each other.
If the "Preselected Slot" can not be measured correctly, this results in an error message
(for example "Underdriven" or "Sync Error"). If there are problems in another slot, but the
"Preselected Slot" is measured correctly, no error message is displayed and the reliability
indicator returned with measurement results equals zero.
3.1.4 Trigger Modes
The TD-SCDMA "Multi Evaluation" measurement can be performed in the following trig-
ger modes (trigger source settings):
●Free Run: The measurement starts immediately after it is initiated. The R&S CMW
decodes the signal to derive its slot and frame timing so that the "Measurement
Length" can start at a frame boundary of the UL TD-SCDMA signal.
●IF Power: With an internal IF power trigger, the measurement is triggered by the
power ramp of the received bursts.
●External Trigger A/B: External trigger signal fed in via TRIG A or TRIG B on the rear
panel of the instrument. Without a configured trigger delay, a subframe trigger signal
is expected.
●Additional trigger modes: Other firmware applications, e.g. the GPRF generator may
provide additional trigger modes. Refer to the documentation of the corresponding
firmware application for a description of these trigger modes. Without a configured
trigger delay, a subframe trigger signal is expected.
For configuration see chapter 4.2.4, "Trigger Settings", on page 44.
3.2 TD-SCDMA RX Tests
RX tests can be carried out in parallel to the TX tests. The following sections describe
how to perform RX tests.
TD-SCDMA RX Tests

General Description
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3.2.1 Test Setup
The downlink RF generator signal of the R&S CMW is fed to the input of the DUT. The
R&S CMW measures the uplink signal. Most conveniently, a bi-directional connection
with a single coax cable is used. The DUT is connected to one of the RF input connectors
(RF COM) at the front panel of the R&S CMW. No additional 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"
Fig. 3-3: Test setup for RX tests
3.2.2 Performing a TD-SCDMA RX Test
For an RX measurement you need to generate a TD-SCDMA downlink signal with an
information bit rate of 12.2 kbps. The DTCH must transport one of the supported data
patterns (see "BER > Data Pattern" on page 43). The signal may contain either a Ref-
erence Measurement Channel (RMC) including both DTCH and DCCH or it may contain
user data only (DTCH only, no DCCH), see "BER > TrCH Mode" on page 43.
The downlink signal can be generated using the GPRF generator and an ARB file. Order
the UE to loop back the received data, using a test mode and measure the resulting uplink
signal using the multi evaluation measurement.
The components of this scenario have to be configured as follows:
●ARB file:
For transport channel mode "RMC" you can use the ARB file named
TD-SCDMA-DL_12k2.wv (uses all 1 pattern).
Alternatively (and for transport channel mode "USER") you can generate an ARB file
using R&S WinIQSIM2 and the following settings:
– Configuration of cell 1 > enhanced channel settings > show DCH details:
Select a 12.2 kbps RMC as coding type.
For transport channel mode "USER", disable the DCCH (the coding type changes
to "User").
Select a data source for the transport channel.
– Marker settings:
Set the user period of marker 4 to 25600 chips (4 subframes).
– Filter/Clipping/ARB settings:
Enter a sequence length of 2 frames (4 subframes).
●GPRF generator:
TD-SCDMA RX Tests

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Select an ARB file (see above) and generate the TD-SCDMA downlink signal.
●UE:
Select an appropriate test mode, so that the UE loops back the received data, via a
12.2 kbps RMC or DTCH (like downlink signal).
●Measurement:
Adjust the settings so that the uplink signal can be measured (see chapter 3.1.2,
"Measuring an Uplink TD-SCDMA Signal", on page 11). Select the GPRF generator
as trigger source. Select the data pattern and transport channel mode corresponding
to the data source used for the ARB file.
The measurement compares the received data with the expected data pattern and pro-
vides the resulting error rates, asuming that all bit errors are caused by the RX part of
the UE. One data block contains 244 bits. They are mapped to four downlink timeslots
located in four subframes. As the first received data block is discarded, the measurement
length must comprise at least two data blocks (8 subframes) and the minimum measured
number of subframes for RX measurements equals 8 (see parameter "No. of Sub-
frames" on page 41). If a smaller value is set, 8 subframes are measured nevertheless.
Enable the BER view only when needed. It slows down the multi evaluation measurement
considerably.
3.3 Multi Evaluation List Mode
The TD-SCDMA multi evaluation list mode requires option R&S CMW-KM012. In this
mode the measurement interval is subdivided into segments, according to basic uplink
signal properties. The list mode can be used to test different modes supported by a UE
(e.g. subframe structures or modulation types) or to cover a wide range of expected
nominal powers or RF frequencies in a single measurement.
Each segment contains an integer number of subframes and is measured at constant
analyzer settings. The figure below shows a series of three segments with different
lengths, expected powers and the listed signal properties. Orange rectangles depict sub-
frames. The maximum number of users per timeslot, the frequency band and the RF
frequency can also be specified per segment.
Multi Evaluation List Mode

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One list mode measurement can cover up to 500 segments with in total up to 1600 sub-
frames. Up to 6 uplink timeslots can be measured per subframe.
In list mode the R&S CMW can measure modulation results and spectrum results. The
measured quantities can be enabled or disabled individually for each segment.
It is possible to limit the measurement to a number of active uplink slots (statistical length)
at the beginning of the segment. The "current" result of a segment refers to the last mea-
sured slot of the statistical length. Additional statistical values (average, maximum and
standard deviation) are calculated for the entire statistical length. The example below
shows a segment with 4 subframes, each containing 2 active UL slots. The statistical
length is set to 5 slots.
The statistical length and statistical values are not relevant for power monitor results. The
power monitor provides a result for each active uplink slot of all measured segments,
independent of the defined statistical length.
If a slot cannot be measured accurately, e.g. because of overflow, low signal or synchro-
nization error, the behavior depends on the parameter Measure on Exception. If it is set
to "Off", the measurement of a segment stops as soon as an error occurs and the mea-
surement continues with the next segment. If it is set to "On", the measurement continues
even when an error occurs. In both cases the reliability indicator for the measurement
and the reliability indicator for the segment indicate the occurred error. Both reliability
indicators are included in the measurement results.
Trigger modes
A list mode measurement can either be triggered only once, or it can be retriggered at
the beginning of specified segments.
In "Once" mode a trigger event is only required to start the measurement. As a result the
entire range of segments is measured without additional trigger event. The trigger is
rearmed after the measurement has been finished. Specified retrigger flags are ignored.
The "Once" mode is recommended for UL signals with accurate timing over the entire
range of segments.
In "Segment" mode the retrigger flag of each segment is evaluated. It defines whether
the measurement waits for a trigger event before measuring the segment, or not. Ret-
riggering the measurement is recommended if the timing of the first slot of a segment is
Multi Evaluation List Mode

General Description
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inaccurate, e.g. because of signal reconfiguration at the UE. Furthermore retriggering
from time to time can compensate for a possible time drift of the UE. The retrigger flag
of the first segment of the measurement is always ignored (implicitly set to ON).
In the example shown below the "Segment" mode is enabled. The retrigger flag is OFF
for the second segment and ON for the third segment. Thus the measurement stops when
the first and second segment have been captured and waits for a trigger event before
capturing the third segment.
The list mode is essentially a single-shot remote control application. When a measure-
ment is initiated in list mode, all defined segments are measured once. Afterwards the
results can be retrieved using FETCh commands. The following remote control com-
mands are used for list mode settings and result retrieval:
Parameters SCPI commands
Activate / deactivate list mode CONFigure:TDSCdma:MEAS<i>:MEValuation:LIST
Number of segments CONFigure:TDSCdma:MEAS<i>:MEValuation:LIST:COUNt
Segment configuration CONFigure:TDSCdma:MEAS<i>:MEValuation:LIST:
SEGMent<Segno>:SETup
Statistical length and result acti-
vation per segment
CONFigure:TDSCdma:MEAS<i>:MEValuation:LIST:
SEGMent<Segno>:MODulation
CONFigure:TDSCdma:MEAS<i>:MEValuation:LIST:
SEGMent<Segno>:SPECtrum
Select trigger mode TRIGger:TDSCdma:MEAS<i>:MEValuation:LIST:MODE
Retrieve results FETCh:TDSCdma:MEAS<i>:MEValuation:LIST:SEGMent<no>:...
FETCh:TDSCdma:MEAS<i>:MEValuation:LIST:...
See chapter 6.3.20, "List Mode Results (One Segment)", on page 123, 
chapter 6.3.21, "List Mode Results (All Segments, One Result)",
on page 129 and chapter 6.3.22, "List Mode Results (All Segments, Result
Groups)", on page 139.
The list mode can be deactivated via command (see table above) and also via the GUI:
1. Go to local using the corresponding hotkey.
The active list mode is indicated at the top of the current view by the words "List
Mode!".
Multi Evaluation List Mode

General Description
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2. Open the configuration dialog and disable the list mode in section "Measurement
Control".
Global and list mode parameters
The RF settings (expected power, RF frequency) and most of the "UE Signal Info" settings
are special list mode settings. The R&S CMW ignores the corresponding "multi evalua-
tion" parameters (e.g. first active uplink slot and switching point). All other settings are
taken from the multi evaluation measurement, e.g. the trigger settings.
3.4 TD-SCDMA Signal Properties
TD-SCDMA is a mobile radio standard in which the available radio resources are divided
among subscribers according to frequency (Frequency Division Multiple Access, FDMA),
time (Time Division Multiple Access, TDMA) and code (Code Division Multiple Access,
CDMA). The same frequency is used for uplink and downlink (Time Division Duplex,
TDD).
3.4.1 Frames and Timeslots
A TD-SCDMA signal is a sequence of radio frames of 10 ms length, each divided into
two subframes of 5 ms length. Each subframe comprises 7 traffic timeslots (TS0 to TS6)
and two special timeslots (DwPTS and UpPTS) for synchronization.
TD-SCDMA Signal Properties

General Description
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TS0 is always allocated to the downlink, TS1 to the uplink. Timeslots 2 to 6 are divided
between the two directions, separated by the switching point. By moving the switching
point the ratio between uplink and downlink data rates can be adapted to increase the
spectrum efficiency.
The downlink pilot timeslot (DwPTS) contains a 32 chip guard period and a 64 chip SYNC
code. This code allows the user equipment (UE) to synchronize to the downlink signal
and defines the value range for the scrambling code and the basic midamble code.
Fig. 3-4: Downlink pilot timeslot structure
The uplink pilot timeslot (UpPTS) contains a 128 chip SYNC code and a 32 chip guard
period.
Fig. 3-5: Uplink pilot timeslot structure
A traffic timeslot contains two data fields, a midamble and a guard period.
The midamble is a training sequence allowing to perform traffic estimation. It is neither
spread nor scrambled. The midamble is obtained from a basic midamble by periodic
repetition and shifting. The basic midamble is a cell-specific bit pattern correlated to a
certain scrambling code.
TD-SCDMA Signal Properties

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Fig. 3-6: Traffic timeslot structure
3.4.2 Channelization for CDMA
Channelization is applied to the data part of physical channels. This operation transforms
each data symbol into a number of chips. The number of chips per data symbol is called
Spreading Factor (SF). The symbol rate of the resulting channel equals the chip rate of
the total signal divided by the spreading factor: Symbol rate (Channel) = 1.28 Mcps / SF
(Channel). For uplink signals the allowed spreading factors are: 1, 2, 4, 8 and 16.
The transformation operation involves channelization codes cSF,k defined in terms of the
spreading factor SF and the index k ranging from 1 to SF (also called channelization code
number). The codes are defined in 3GPP TS 25.223 and are derived from a hierarchical
tree:
These codes are Orthogonal Variable Spreading Factor (OVSF) codes, allowing to
superimpose channels with different spreading factors in the same timeslot while pre-
serving the orthogonality. When assigning spreading factors and channelization codes
(code numbers) to channels, one rule has to be observed to preserve orthogonality:
Within each branch only one code can be used at the same time.
This means:
●Other codes on the path between the code and the root of the tree must not be used.
●Codes in sub-branches of the code (to the right of the code) must not be used.
For an example see the figure below. The red parts are blocked when c4,4 is used.
TD-SCDMA Signal Properties

General Description
R&S®CMW-KM750/-KM751
20User Manual 1173.9670.02 ─ 05
3.5 Limit Settings and Conformance Requirements
Conformance requirements for TD-SCDMA transmitter tests are specified in 3GPP TS
34.122, section 5, "Transmitter Characteristics".
The following sections give an overview of the R&S CMW limit settings and the related
test requirements.
●Transmit Modulation Limits.....................................................................................20
●Power Templates....................................................................................................21
●ACLR Limits............................................................................................................22
●Spectrum Emission Mask........................................................................................23
3.5.1 Transmit Modulation Limits
A poor modulation accuracy of the UE transmitter increases the transmission errors in
the uplink channel of the TD-SCDMA network. The Error Vector Magnitude (EVM) is the
critical quantity to assess the modulation accuracy of a TD-SCDMA UE.
According to 3GPP, the EVM measured at UE output powers ≥ −20 dBm and under
normal operating conditions shall not exceed 17.5 %. In addition, the Peak Code Domain
Error, which is the maximum EVM of all code channels, shall not exceed –20 dB. The
frequency error shall not exceed ±0.1 ppm. These limits can be set in the configuration
dialog, along with limits for the other measured quantities.
Limit Settings and Conformance Requirements