Tektronix NetTek YBT250, Руководство пользователя

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Taking Measurements
YBT250 Field Transmitter & Interference Tester User Manual
3- 121
Hints
H
Tap the Restart icon to clear the trace history and restart
collecting data.
H
Select Updates... to change how often the codogram is updated.
H
To find the timestamp (displayed next to the Data Record box)
for a specific data record in the Codogram, tap the
Data Record
box. The cursor is the horizontal white band. Use the knob or
numeric keypad to move the cursor to the data record of interest.
The time and date the selected data was recorded is displayed to
the right of the Data Record box.
H
You can save a Codogram to a file every 80 records, by setting
the option on the Meter tab of the Setup window.
cdma2000 Codogram Results Export File Format
A cdma2000 Codogram result file contains three major blocks of
Codogram data, each of which is 128 rows by 80 columns. In each
block, each column is a data set from a single Code Power (CP)
measurement result. The row above the first row of data in each
block contains the timestamp for the CP data in that column. The
128 rows per block correspond to the CP results from analyzing the
signal at a Spreading Factor (SF) of 128.
Block 1 (file rows 23-150) lists the linear order Code Power for
codes analyzed at only the Spreading Factor of 128. This information
shows the daughter code levels of any active codes, along with the
noise code levels of inactive codes. Only codes that are SF of 128
show their correct CP in this block. Active codes with lower
Spreading factors show their power spread out among the corre-
sponding multiple daughter codes at this level.
Block 2 (rows 154-281) lists the detected (parent) code Code Power
values, in bit-reversed order. The detected parent code Code Power
level is copied to all of the 128/SF bit-reversed daughter code
indices that comprise the active parent code (these are consecutive
codes in the bit reverse display). This level is used for the flying bar
in the Code Power display, and also determines the Codogram
level color.