Tektronix RSA6100A Series, Help Manual

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RF Measurements > Channel Power and ACPR RF Channel Power Measurement
Setting Channel Power and ACPR Settings Parameters (see page 136)
RF Channel Power Measurement
The RF channel power gives an indication of the total average (and other measures ) RF power in
a given channel.
For some communications systems, there is an “out-of-service” total power measurement de fi ned in the
speci fi cations that calls for a speci fi ed constant modulation. In this case, the output power should be
relatively constant. For many measurements, this may not be the case, and the Power Measurement
results will vary as the signal varies.
Average power is the square root of the sum of the squares of the voltage samples over the measurement
time.
The de fi ned “channel” width for the Power Measurement de fi nes the bandwidth and shape of the fi lter
used to remove any RF power on frequencies outside of the channel bandwidth.
Channel Power
The total RF power in the selected frequency band. The detection type used for measuring channel power
is Average. This means that the average of the linear (pre-log) samples is used to determine the channel
power. To measure channel power, use the ACLR measurement, and set the number of adjacent channels
to zero. This results in only the channel power being measured.
Average Channel Power
The total RF power in the selected channel (located in the ACPR display).
Adjacent Channel Leakage Power Ratio
Adjacent Channel Leakage power Ratio (ACLR) is the ratio of the mean power centered on the
assigned channel frequency to the mean power centered on an adjacent channel frequency. In the 3GPP
speci
fi cation, both the main channel and adjacent channels are required to be fi ltered with RRC (Root
Raised Cosine) fi lters.
RSA6100A Series Real-Time Spectrum Analyzers Help
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