Agilent Technologies X Series Programmer's Manual page 22

Introduction to Programming X-Series Applications
SCPI Measurement Commands
trace data. For I/Q trace data, the minimum magnitude of the I/Q pairs is returned.
• MAXimum - returns the maximum data point (x,y pair) for the specified region(s) of
trace data. For I/Q trace data, the maximum magnitude of the I/Q pairs is returned.
MEAN - returns a single value that is the arithmetic mean of the data point values (in dB/
dBm) for the specified region(s) of trace data. For I/Q trace data, the mean of the
magnitudes of the I/Q pairs is returned. See the following equations.
If the original trace data is in dB, this function returns the arithmetic
NOTE
mean of those log values, not log of the mean power which is a more
useful value. The mean of the log is the better measurement technique
when measuring CW signals in the presence of noise. The mean of the
power, expressed in dB, is useful in power measurements such as
Channel Power. To achieve the mean of the power, use the RMS option.
Equation 1
Mean Value of Data Points for Specified Region(s)
Σ
1 _
Xi
MEAN =
n
Xi ∈ region(s)
where Xi is a data point value, and n is the number of data points in the specified
region(s).
Equation 2
Mean Value of I/Q Data Pairs for Specified Region(s)
Σ
1 _
|Xi|
MEAN =
n
Xi ∈ region(s)
where |Xi| is the magnitude of an I/Q pair, and n is the number of I/Q pairs in the
specified region(s).
• DMEan - returns a single value that is the mean power (in dB/ dBm) of the data point
values for the specified region(s) of trace data. See the following equation:
Equation 3
DMEan Value of Data Points for Specified Region(s)
10 x log
DME =
10
• RMS - returns a single value that is the average power on a root-mean-squared voltage
scale (arithmetic rms) of the data point values for the specified region(s) of trace data.
See the following equation.
22
Σ
1 _
Xi
10
n
Xi ∈ region(s)
vsd27-1
vsd27-2
vsd27-3
Chapter 1