Agilent Technologies E4428C, Руководство пользователя

Страница: 213 / 700

Chapter 4 189
Basic Digital Operation
User-Defined I/Q Maps
Entering I and Q Values
Enter the I and Q values listed in the following table.
1. Press
.5
>
Enter
.
2. Press
1
>
Enter
.
3. Enter the remaining I and Q values.
As the I value updates, the highlight moves to the first Q entry (and provides a default value of 0), and an
empty row of data appears below the first row. As the Q value updates, and the highlight moves to the next I
value. As you press the numeric keys, the numbers display in the active entry area. If you make a mistake,
use the backspace key and then retype.
Also note that
0.000000
appears as the first entry in the list of
Distinct Values
, and that
0.500000
and
1.000000
are listed as the distinct values.
Displaying the I/Q Map
1. Press
Display I/Q Map
An I/Q map generated using the current values in the
I/Q Values
table editor is displayed.
The map in this example has four symbols. The map uses the following four unique values: 0.5, 1.0,
−
0.5, and
−
1.0 to create the four symbols. It is not the number of values that defines how many symbols
a map has, but how those values are combined.
2. Press
Return
.
When the contents of a table editor have not been stored,
I/Q Values (UNSTORED)
appears on the
display. Follow the instructions in the next section to store the custom I/Q table.
Symbol Data Bits I Value Q Value
0
0000 0.500000 1.000000
1
0001 −0.500000 1.000000
2
0010 0.500000 −1.000000
3
0011 −0.500000 −1.000000