Freedom R8100 SERIES, Руководство оператора

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Figure 2.2.7.7-3. Error Vector Diagram
EVM (Peak)
The Peak error vector magnitude for a burst is the maximum error distance found over the burst.
Unwanted Power
Unwanted Power is meant to measure the average power in non-active regions of non-active timeslots.
The expected bursts to be transmitted are in every slot 1 and sometimes slot 3. Slots 2 and 4 of all frames
are always non-active. The active region of a non-active slot is for ramping of an adjacent active slot. The
measurement is done at the optimal symbol times and positions to exclude adverse effects of frequency
error and residual carrier.
Reset Averaging (TETRA submenu)
All TETRA measurements, history, and displays are reset, including ones in other zones.
Measurement Averaging (TETRA submenu)
Configures measurement averaging to smooth selective readings. The number of samples used can be
from 1 (no averaging) to 250. Samples are collected 5 to 17 times per second. Measurement averaging
affects the following:
RF Zone – Input Level
TETRA Zone – Residual Carrier Magnitude, EVM (RMS), EVM (Peak), Unwanted Power.
Unwanted Power in Slot 3 (TETRA submenu)
Configures the Unwanted Power measurement. If “No”, the computed measurement is the average power
in slots 2 and 4 only, excluding active regions for adjacent slots. If “Yes”, it is the average power in slots
2, 3 and 4, excluding the active region(s) for slot 1.
Note: Unwanted power could be systemic or transient in nature. Use of this switch may be used to identify
its nature. The average unwanted power of a systemic source will be the same for either setting but of
transients in slot 2 or 4 will decrease for “Yes” (assuming slot 3 is not active).