Tektronix RSA6100A Series, Help Manual

Page: 157 / 415

RF Measurements > MCPR Measurement Params for ACPR and MCPR
Displays
Parameter Description
Average
Enables/disables measurement averaging. Averaging can be enabled in either the
Frequency Domain or Time Domain.
Frequency-domain averaging This setting takes the average linear value of the traces (so that rms values are
preserved). The number of averages is user-de
fi ned. Frequency domain averaging
is available in spans larger (or smaller) than the maximum real time bandwidth.
This is the mode to use unless you need to extract maximum dynamic range from
an ACPR measurement.
Time-domain averaging This setting takes the average linear value of the traces. It is useful if you need to
extract maximum dynamic range from an ACPR measurement. The number of traces
is user de
fi ned. But, the signals must be triggered and repeating. That is, the signal
needs to be exactly the same for each acquisition. When this condition is met, each
waveform contains the same signal, but the random noise changes from acquisition
to acquisition and the average value of the random noise is lowered, while the signal
value remains constant. Time domain averaging is not available in spans wider
than the maximum real-time bandwidth.
Number Speci fi es the number of acquisitions to be averaged when Averaging is set to
Frequency Domain. Speci fi es the number of successive capture records that are
averaged when Averaging is set to Time Domain.
Correct for Noise Floor Enables/disables the Noise Floor Correction function.
Optimization Sets the Noise Floor Correction function to optimize for the greatest dynamic range
or the widest real-time bandwidth.
Power Reference Speci fi es power against which the results are compared. Choices available are each
of the existing main channels and “Total power in main channels”.
Only present when MCPR is the selected display.
Channel Filter Specify the channel fi lter used. Select between None (default) and Root-raised
Cosine.
Filter Parameter Value entry box for the Root-raised Cosine fi lter Adjacent Channel Filter.
Present only when the Channel Filter is set to RRC.
Chip Rate Value entry box for the RRC chip rate.
Present only when the Channel Filter is set to RRC.
xxx
Correct for Noise Floor
When this setting is enabled, the instrument applies a correction to the ACPR or MCPR measurement to
reduce the effect of instrument noise on the results. It generates this correction by taking a preliminary
acquisition to measure the instrument noise
fl oor. Once this is done, the measurement proceeds, applying
the correction to each result. When any relevant settings (reference level, attenuator, frequency, or span)
are changed, the instrument performs a new noise measurement and correction.
Optimization
There are two settings for Optimization: Dynamic Range and Realtime BW.
Realtime BW : Choose Realtime BW when you want to see time-correlated results in other displays.
Optimizing for real-time bandwidth causes the instrument to set its acquisition bandwidth to span the
RSA6100A Series Real-Time Spectrum Analyzers Help
145