Tektronix NetTek YBT250, User Manual

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Taking Measurements
YBT250 Field Transmitter & Interference Tester User Manual
3- 131
To measure ACLR:
1. Tap the Measurement button.
2. Select a W-CDMA signal standard.
3. Tap Select Measurement .
4. Tap ACLR . See Figure 3--65.
Figure 3- 65: A typical ACLR display
Four adjacent channels, the two closest on either side of the assigned
channel, are measured: the Upper1/Lower1 adjacent channels are
centered 5 MHz above and below the assigned channel center, and
the Upper2/ Lower2 channels are 10 MHz above and below the
assigned channel center.
Each ACLR result is computed by subtracting the corresponding
adjacent channel filtered power value from the assigned channel
filtered power. The ACLR measurement page displays the four
ACLR results for the Lower and Upper adjacent channels, as well as
the filtered channel power for the assigned channel and the adjacent
channels. ACLR values increase with improved signal leakage
suppression, so larger positive values are better.