Keysight Technologies N9340B, User Manual

Page: 69 / 172

Making Measurements
Making an Average Power Measurement
63
Making an Average Power Measurement
Average power measurements provide a key metric in
transmitter performance.
Base station transmit power must be set accurately to
achieve optimal coverage in wireless networks. If the
transmit power is set too high due to inaccurate power
measurements, undesired interference can occur. If the
transmit power is set too low, coverage gaps or holes
may occur. Either case may affect system capacity and
may translate into decreased revenue for service
providers.
Average power can be measured for the channel of
interest while the base station is active. All other
channels should be inactive. Average power is a
broadband measurement. If other signals are present the
analyzer will also measure their power contributions.
The analyzer supports the U2000 Series USB power
sensors.
The U2000 Series USB power sensors do not need
manual calibration and zero routines performed.
Calibration and zeroing are performed without removing
the power sensor from the source, through internal
zeroing. With internal zeroing of U2000 Series USB
power sensors, there is no need to disconnect the
sensor or power
-
off the DUT. The U2000 Series do not
require 50 MHz reference signal calibration, allowing the
factory calibration to ensure measurement accuracy. For
CAU-
CAUTION
The maximum power for the RF IN port and the RF OUT port
of the analyzer is +20 dBm. The maximum power for the
Power Sensor port is +24 dBm. When directly coupled to a
base station, the test set can be damaged by excessive power
applied to any of these three ports.
To prevent damage in most situations when directly coupling
an analyzer to a base station, use a high power attenuator
between the analyzer and the BTS.