RIGOL DSA875 - Manual (Page 78)

RIGOL Chapter 2 Front Panel Operation
User’s Guide for DSA800 Series 2-26
3. Sample
For each trace point, Sample detector displays the transient level
corresponding to the central time point of the corresponding time interval.
This detector type is applicable to noise or noise-like signal.
4. Normal
Normal detector (also called rosenfell detector) displays the maximum value and
the minimum value of the sample data segment in turn; namely for an
odd-numbered data point, the maximum value is displayed; for an
even-numbered data point, the minimum value is displayed. In this way, the
amplitude variation range of the signal is clearly shown.
5. RMS Avg
For each data point, perform mean square root operation (see equation (2-8))
of the sampled data within the corresponding time interval and display the
result. In this type, noise can be rejected and weak signals can be clearly
observed.
∑
=
× =
N
i RMS
v
N
V
1 i
2
1
(2-8)
Wherein,
RMS
V
is the mean square root of voltage in V;
N
is the number of
sampled values for each point displayed;
i
v
is the envelop of the sampled
value in V. The reference impedance
R can be used for power calculation:
R
v
P RMS
2
= .
6. Voltage Avg
For each data point, average (see equation (2-9)) all the sampled data within
the corresponding time interval and display the result.
∑
=
× =
N
i AV
v
N
V
1 i
1
(2-9)
Wherein,
AV
V
is the average of voltage in V;
N is the number of sampled
values for each point displayed;
i
v
is the envelop of the sampled value in V.