Anritsu 3GPP, Руководство по измерениям

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4-4 TD-SCDMA/HSPA+ Demodulator TD-SCDMA/HSPA+ Signal Analyzer
4-8 PN: 10580-00234 Rev. Y 3GPP MG
Scrambling Codes
The display format is Scrambling Code # (relative power in dB). A measure of the relative
powers of the four scrambling codes (relative to Slot Power) that correspond to the detected
SYNC-DL code. Only those scrambling codes with high relative power are displayed.
Typically, only one scrambling code is displayed unless significant interference occurs from
neighboring codes.
EVM
The Error Vector Magnitude (EVM) is the ratio (in percent) of the difference between the
reference waveform and the measured waveform. EVM metrics are used to measure the
modulation quality of a transmitter. The EVM value displayed by the instrument is the root
mean square EVM of the measured downlink slot data.
Peak EVM
The peak of the measured EVM.
Peak CDE
The peak of the Code Domain Error (CDE) is the remnant power in the code domain after the
useful signal is extracted.
Measurement Setup
Refer to the User Guide for selecting the TD-SCDMA/HSPA+ Signal Analyzer mode and
continue with the following setups for the specific Demodulator measurements.
1. Press the
Setup
main menu key.
a. Press the
Slot Selection
submenu key. The Slot Selection window and menu open.
In the list window, use the rotary knob or press the touch screen to highlight
Auto
or the desired slot (0 to 6), then press the
Enter
key.
b. Press the
Trigger
submenu key. The Trigger menu opens.
1. Press the
Trigger Type
submenu key to toggle through the three trigger types:
No
Trig
,
GPS
, and
Ext
. The active state is underlined on the face of the submenu key.
2. Press the
Ext Trigger Polarity
submenu key to toggle either
Rising
or
Falling
trigger
edge.
3. Press the
Back
submenu key to return to the Setup menu.
c. Press the
Uplink Switch Point
submenu key. The numerical value on the face of
the submenu key turns red and is ready to be edited. Use the arrow keys or the
rotary knob to change the value. You can also use the numeric keypad, then press
Enter
.
d. Press the SYNC-DL Code submenu key. The SYNC-DL Code menu and selection
window open. Use the rotary knob or press the touch screen to highlight
Auto
or
the desired code (0 to 31), then press
Enter
.
e. Press the Scrambling Midamble Code submenu key to open the Scrambling Code
selection window and menu. Use the rotary knob or press the touch screen to
highlight
Auto
or the desired code (0 to 127), then press the
Enter
key.
f. Press the
Max Users
submenu key to open the Maximum Users selection window
and menu. Use the rotary knob or press the touch screen to highlight
Auto
or the
desired value (2 to 16), then press
Enter
.