Agilent Technologies 89410A User Manual

To create an ideal digitally modulated signal
You may create a digitally modulated signal by using noise as the input and
saving the reference signal of your selected demodulation format. You may
check the created signal by playing it through the source as shown in the
following task. This example creates a 32QAM signal but most digitally
modulated signal types may be created in a similar way (see text on
following page). The waveform created by the following procedure is
included on the Signals Disk as “32QAM.DAT”.
This task uses digital demodulation. If you want to perform this task using
video demodulation, choose video demodulation instead of digital
demodulation in step 3.
1. Initialize the analyzer:
Press [
Instrument Mode
], [
receiver
], then press:
89410A: [
input section (0-10 MHz)
].
89441A: [
RF section (0-10 MHz)
].
Press [
Preset
].
Press [
Instrument Mode
], [
vector
].
2. Select a center frequency and span:
Press [
Frequency
], [center], 5, [
MHz
]
Press [
span
], 61, [
kHz
].
3. Select a digital demodulation format:
Press [
Instrument Mode
], [
Digital Demodulation
] (with option AYH, press
[
Instrument Mode
], [
demod type
], [
Digital Demodulation
], [
Return] ).
Press
[demodulation setup
].
Pre ss [
demod format
], [
QAM 32
].
4. Select demodulation format parameters:
Press [
Return
], [
symbol rate
], 30.5, [
kHz
],
Press [
result length
], 240, [
sym
]
Press [
ref filter
], [
root raised cosine
]
Pres s [
Return
], [
alpha / BT
], .5, [
enter
]
Press [
more
], [
normalization
on].
Press [
Time
], [
points/symbol
], 5, [
enter
],
Press [
pulse search off], [sync search off
].
5. Select a reference time display (the Data Format is irrelevant):
Press [
Measurement Data
], [
IQ reference time
]
Press [
Data Format
], [
polar (IQ) constellation
]
Press [
Auto Scale
].
6. Save the signal to a register:
Press [
Save/Recall
], [
save trace
], [
into D1
].
7. You may want to the save the created signal to a disc for more permanent
storage:
Press [
Save Recall
], [
save trace
], [
into file
], and enter a file name.
Creating User-defined Signals (Options AYA and AYH)
11 - 2

Agilent Technologies 89410A Specifications

General

Brand	Agilent Technologies
Model	89410A
Category	Measuring Instruments
Language	English