Using a predefined fir filter – Agilent Technologies E8247C PSG CW User Manual
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Chapter 6
Custom Arb Waveform Generator
Working with Filters
•
Filter Alpha
enables you to adjust the filter alpha for a Nyquist or root Nyquist filter. If a Gaussian filter is
used, you will see Filter BbT; this softkey is grayed out when any other filter is selected.
•
(Custom Realtime I/Q Baseband Only) Optimize FIR for EVM ACP enables you to optimize a Nyquist
or root Nyquist filter for minimized error vector magnitude (EVM) or for minimized adjacent channel
power (ACP); the softkey is grayed out when any other filter is selected.
•
Restore Default Filters
replaces the current FIR filter with the default FIR filter for the selected format.
Using a Predefined FIR Filter
Selecting a Predefined FIR Filter
1. Preset the instrument: Press
Preset
.
2. Press
Mode
>
Custom
>
ARB Waveform Generator
>
Digital Mod Define
>
Filter
>
Select
or
Mode
>
Custom
>
Real Time I/Q Baseband
>
Filter
>
Select
>
3. Select the desired filter. If the filter you want is not in the first list, press
More (1 of 2)
.
Adjusting the Filter Alpha of a Predefined Root Nyquist or Nyquist Filter
1. Preset the instrument: Press
Preset
.
2. Press
Mode
>
Custom
>
ARB Waveform Generator
>
Digital Mod Define
>
Filter
>
Filter Alpha
or
Mode
>
Custom
>
Real Time I/Q Baseband
>
Filter
>
Filter Alpha
3. Enter a new Filter Alpha value and press
Enter
.
Adjusting the Bandwidth-Bit-Time (BbT) Product of a Predefined Gaussian Filter
1. Press
Mode
>
Custom
>
ARB Waveform Generator
>
Digital Mod Define
>
Filter
>
Select
>
Gaussian
or
Mode
>
Custom
>
Real Time I/Q Baseband
>
Filter
>
Select
>
Gaussian
2. Press
Filter BbT
.
3. Enter a new Bandwidth-Bit-Time (BbT) product filter parameter and press
Enter
.
Optimizing a Nyquist or Root Nyquist FIR Filter for EVM or ACP (Custom Realtime I/Q Baseband only)
1. Preset the instrument: Press
Preset
.
2. Press
Mode
>
Custom
>
Real Time I/Q Baseband
>
Filter
>
Optimize FIR For EVM or ACP
.
The FIR filter is now optimized for minimum error vector magnitude (EVM) or for minimum adjacent
channel power (ACP). This feature applies only to Nyquist and root Nyquist filters; the softkey is grayed
out when any other filter is selected.