Agilent Technologies N9020A User manual

Agilent Technologies
Agilent X-Series
Signal Analyzer
N9079A TD-SCDMA with
HSPA/8PSK Measurement
Application Measurement
Guide
This manual provides documentation for the
following X-Series Analyzers:
MXA Signal Analyzer N9020A
EXA Signal Analyzer N9010A

Notices
© Agilent Technologies, Inc. 2007-2008
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Manual Part Number
N9079-90005
Supersedes:N9079-90006
Print Date
August 2008
Printed in USA
Agilent Technologies, Inc.
1400 Fountaingrove Parkway
Santa Rosa, CA 95403
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Contents
5
1. Making TD-SCDMA with HSPA/8PSK Measurements
Setting Up and Making a Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Making the Initial Signal Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Using Analyzer Mode and Measurement Presets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
The 3 Steps to Set Up and Make Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2. Transmit Power Measurements
Configuring the Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3. ACP Measurements
Configuring the Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4. Power vs. Time Measurements
Configuring the Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
5. Spectrum Emission Mask Measurements
Configuring the Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
6. Spurious Emissions Measurement
Configuring the Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
7. Occupied Bandwidth Measurements
Configuring the Measurement System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

6
Contents
8. Power Statistics CCDF Measurements
Configuring the Measurement System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .61
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
9. Modulation Accuracy (Composite EVM) Measurements
Configuring the Measurement System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .66
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
10. Code Domain Measurements
Configuring the Measurement System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82
11. IQ Waveform (Time Domain) Measurements
Configuring the Measurement System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .84
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .87
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
12. Monitor Spectrum Measurements
Configuring the Measurement System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90
Setting the BTS (Example) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .91
Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .92
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .93
13. Using Option BBA Baseband I/Q Inputs
Baseband I/Q Measurements Available for X-Series Signal Analyzers . . . . . . . . . . . . . . . . . .96
Baseband I/Q Measurement Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
14. Baseband I/Q Inputs (Option BBA) Measurement Concepts
What are Baseband I/Q Inputs? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .100
What are Baseband I/Q Signals? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
Why Make Measurements at Baseband? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102
Selecting Input Probes for Baseband Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
Supported Probes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
Probes without Stored Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .105
Baseband I/Q Measurement Views. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106
Spectrum Views and 0 Hz Center Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106
Waveform Views for Baseband I/Q Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106

Contents
7
Waveform Signal Envelope Views of I only or Q only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

8
Contents

9
1Making TD-SCDMA with
HSPA/8PSK Measurements
This chapter begins with instructions common to all measurements,
then details all the measurements available by pressing the Meas key
when the TD-SCDMA with HSPA/8PSK mode is selected.
NOTE If you only install Option N9079-1FP, press TD-SCDMA to select the
TD-SCDMA mode.
If you install both Option N9079-1FP and Option N9079-2FP, press
TD-SCDMA with HSPA/8PSK to select the TD-SCDMA mode.
For information specific to individual measurements, see the sections at
the page numbers below.
•“Transmit Power Measurements” on page 13
•“ACP Measurements” on page 21
•“Power vs. Time Measurements” on page 29
•“Spectrum Emission Mask Measurements” on page 37
•“Spurious Emissions Measurement” on page 45
•“Occupied Bandwidth Measurements” on page 51
•“Power Statistics CCDF Measurements” on page 57
•“Code Domain Measurements” on page 73
•“Modulation Accuracy (Composite EVM) Measurements” on page 65
•“IQ Waveform (Time Domain) Measurements” on page 83
•Chapter 12 , “Monitor Spectrum Measurements,” on page 89

10 Chapter 1
Making TD-SCDMA with HSPA/8PSK Measurements
Setting Up and Making a Measurement
Setting Up and Making a Measurement
Making the Initial Signal Connection
CAUTION Before connecting a signal to the analyzer, make sure the analyzer can
safely accept the signal level provided. The signal level limits are
marked next to the RF Input connectors on the front panel.
See the Input Key menu for details on selecting input ports and the
AMPTD Y Scale menu for details on setting internal attenuation to
prevent overloading the analyzer.
Using Analyzer Mode and Measurement Presets
To set your current measurement mode to a known factory default
state, press Mode Preset. This initializes the analyzer by returning the
mode setup and all of the measurement setups in the mode to the
factory default parameters.
To preset the parameters that are specific to an active, selected
measurement, press Meas Setup, Meas Preset. This returns all the
measurement setup parameters to the factory defaults, but only for the
currently selected measurement.
The 3 Steps to Set Up and Make Measurements
All measurements can be set up using the following three steps. The
sequence starts at the Mode level, is followed by the Measurement
level, then finally, the result displays may be adjusted.
Table 1-1 The 3 Steps to Set Up and Make a Measurement
Step Action Notes
1. Select and Set Up
the Mode
a. Press Mode
b. Press a mode key, like
Spectrum Analyzer, W-CDMA
with HSDPA/HSUPA, or
GSM/EDGE.
c. Press Mode Preset.
d. Press Mode Setup
All licensed, installed modes
available are shown under the
Mode key.
Using Mode Setup, make any
required adjustments to the
mode settings. These settings
will apply to all measurements
in the mode.

Chapter 1 11
Making TD-SCDMA with HSPA/8PSK Measurements
Setting Up and Making a Measurement
NOTE A setting may be reset at any time, and will be in effect on the next
measurement cycle or view.
2. Select and Set Up
the Measurement
a. Press Meas.
b. Select the specific
measurement to be performed.
c. Press Meas Setup
The measurement begins as soon
as any required trigger
conditions are met. The resulting
data is shown on the display or is
available for export.
Use Meas Setup to make any
required adjustment to the
selected measurement settings.
The settings only apply to this
measurement.
3. Select and Set Up a
View of the Results
Press View/Display. Select a
display format for the current
measurement data.
Depending on the mode and
measurement selected, other
graphical and tabular data
presentations may be available.
X-Scale and Y-Scale adjustments
may also be made now.
Table 1-2 Main Keys and Functions for Making Measurements
Step Primary Key Setup Keys Related Keys
1. Select and set up a mode. Mode Mode Setup,
FREQ Channel
System
2. Select and set up a
measurement.
Meas Meas Setup Sweep/Control,
Restart, Single, Cont
3. Select and set up a view of the
results.
View/Display SPAN X Scale,
AMPTD Y Scale
Peak Search,
Quick Save, Save,
Recall, File, Print
Table 1-1 The 3 Steps to Set Up and Make a Measurement
Step Action Notes

12 Chapter 1
Making TD-SCDMA with HSPA/8PSK Measurements
Setting Up and Making a Measurement

13
2Transmit Power Measurements
This section explains how to make a Transmit Power measurement on a
TD-SCDMA base transceiver station (BTS), a mobile station (MS), a
repeater or a power amplifier (PA). This test measures the average RF
power present in the channel.
There are three methods to determine the power level:
• At or above a specified threshold value;
• Within the detected burst width;
• Captured in single timeslot.
The results are shown in a graph window and in a text window.

14 Chapter 2
Transmit Power Measurements
Configuring the Measurement System
Configuring the Measurement System
The BTS under test have to be set to transmit the RF power remotely through the
system controller. This transmitting signal is connected to the analyzer RF input
port. Connect the equipment as shown.
Figure 2-1 Transmit Power Measurement System
1. Using the appropriate cables, attenuator and adapters, connect the output signal
of the BTS to the RF input of the analyzer.
2. Connect a BNC cable between the frequency reference port of the BTS and the
EXT REF IN port of the analyzer.
3. Connect the Trigger Out from the BTS to the TRIGGER1 IN port of the
analyzer.
4. Connect the system controller to the BTS through the serial bus cable to control
the BTS operation.

Chapter 2 15
Transmit Power Measurements
Setting the BTS (Example)
Setting the BTS (Example)
From the BTS and the system controller, set up a call using loopback mode for the
BTS to transmit the RF power as follows:
Frequency: 2.0 GHz
Output Power: −20 dBm
Carrier Number: 1
Switching Point: 3
Scramble Code: 0
Table 2-1 Timeslot Setup
Timeslot State
0On
1On
2On
3On
4Off
5Off
6Off
DwPTS On
UpPTS Off

16 Chapter 2
Transmit Power Measurements
Measurement Procedure
Measurement Procedure
Step 1. Press Mode, TD-SCDMA with HSPA/8PSK to enable the TD-SCDMA mode
measurements.
Step 2. Press Mode Preset to preset the analyzer.
Step 3. Press Input/Output, External Gain, BTS and enter the number and −dB according
to the external attenuator connected to the analyzer.
Step 4. Press Mode Setup, Radio, Device to toggle the device to BTS.
Step 5. Press Mode Setup, Analysis TimeSlot, TS0 to select the timeslot to be analyzed.
Step 6. Press Meas, Transmit Power to initiate the Transmit Power measurement.
Step 7. Press FREQ Channel, 2, GHz to set the center frequency to 2 GHz.
Step 8. Press Trigger and select the approriate trigger source according to the external
trigger connection External 1.
If no measurement is performed and only a symbol of yellow ‘*’ displays on the
top right of the screen, you need to check the trigger settings. You need the correct
trigger signal to make the Transmit Power measurement.
Step 9. Press Meas Setup to check the keys available to change the measurement
parameters from the default condition.
To change the algorithm to measure the power, press Meas Method and select the
desired method from the listed three method: Above Threshold Lvl, Measured
Burst Width, or Single Time Slot.
NOTE When you select Above Threshold Lvl, the Burst Width key will be grayed out.
When you select Single Time Slot, the Threshold Lvl key and the Burst Width
key will be grayed out.
You can adjust the parameters for the selected method as follows:
• To set a relative threshold level for the measurement, press Threshold Lvl to
toggle the state to Rel and enter the desired value.
• To set a burst width for the measurement, press Burst Width to toggle the state
to Man and enter the desired value.
When you press Mode Setup, Radio and toggle the Device key to MS, the
Meas Method will automatically switch to Burst Width.
• To capture multiple bursts, press More and Meas Interval and enter the desired
value to extend the measurement period (default setting is 1 slot).
NOTE When the analyzer can not find a valid burst width, it’s recommended to extend the

Chapter 2 17
Transmit Power Measurements
Measurement Procedure
Meas Interval and increase the Threshold Lvl until a valid result is displayed.
For more details about changing measurement parameters, see N9079A
TD-SCDMA with HSPA/8PSK User’s and Programmer’s Reference.
If you have a problem, and get an error message, see the “Instrument Messages
Guide”.

18 Chapter 2
Transmit Power Measurements
Measurement Results
Measurement Results
Figure 2-2 shows the Transmit Power in single timeslot.
The Output Power is displayed on the left of the text window and on the right
under the heading Current Data Output Pwr. If averaging is turned off, the two
values will be the same. When you turn averaging on, the left Output Power is an
averaged value of “n” times measurements, while the current data Output Pwr
indicates the result of the last measurement.
Figure 2-2 Transmit Power - Single Timeslot

Chapter 2 19
Transmit Power Measurements
Measurement Results
Figure 2-3 shows the Transmit Power measured by burst width.
Full Burst Width and Measured Width (Burst Width) are displayed in the text
window, as well as the Threshold levels used to calculate the burst center. When
the default Burst Width is inappropriate to perform a measurement, it’s
recommended to increase the Meas Interval and Threshold Lvl or to manually
enter the desired Burst Width value.
Figure 2-3 Transmit Power - Measured Burst Width
Figure 2-4 shows the Transmit Power above threshold level.
Absolute Amplitude Threshold and Relative Amplitude Threshold are displayed.
The relative threshold is defined as relative to the peak power.
Figure 2-4 Transmit Power - Above Threshold Lvl

20 Chapter 2
Transmit Power Measurements
Troubleshooting Hints
Troubleshooting Hints
Low output power can lead to poor coverage and intermittent service for phone
users. Out of specification power measurements indicate a fault usually in the
power amplifier circuitry. They can also provide early indication of a fault with the
power supply, for example the battery in the case of mobile stations.