Agilent Technologies E8257D PSG, E8267D PSG manual Working with Burst Shapes

Custom Real Time I/Q Baseband

Working with Burst Shapes

To Apply Bit Errors to an Existing Data Pattern User File

This example demonstrates how to apply bit errors to an existing data pattern user file. If you have not created and stored a data pattern user file, first complete the steps in the previous section, “Creating a Data Pattern User File with the Bit File Editor” on page 167.

1.Press Apply Bit Errors.

2.Press Bit Errors > 5 > Enter.

3.Press Apply Bit Errors.

Notice both Bit Errors softkeys change value as they are linked.

Using an Externally Supplied Data Pattern

In this procedure, an external real time data pattern is supplied through DATA, DATA CLOCK, and SYMBOL SYNC connectors.

1. Press Preset.

2. Press Mode > Custom > Real Time I/Q Baseband > Data > Ext.

3.Connect the real- time data to the DATA input.

4.Connect the data clock trigger signal to DATA CLOCK input.

5.Connect the symbol sync trigger to the SYMBOL SYNC input.

Working with Burst Shapes

•“Configuring the Burst Rise and Fall Parameters” on page 172

•“Using User- Defined Burst Shape Curves” on page 172

The Burst Shape menu enables you to modify the rise and fall time, rise and fall delay, and the burst shape (either sine or user file defined). In addition, you can define the shape of the burst and preview the burst shape through a Rise Shape Editor, or restore all of the burst shape parameters back to their original default state.

Rise time	the period of time, specified in bits, where the burst increases from a minimum of
	−70 dB (0) to full power (1).
Fall time	the period of time, specified in bits, where the burst decreases from full power (1)
	to a minimum of −70 dB (0).
Rise delay	the period of time, specified in bits, that the start of the burst rise is delayed.
	Rise delay can be either negative or positive. Entering a delay other than zero
	shifts the full power point earlier or later than the beginning of the first useful
	symbol.
Fall delay	the period of time, specified in bits, that the start of the burst fall is delayed. Fall
	delay can be either negative or positive. Entering a delay other than zero shifts
	the full power point earlier or later than the end of the last useful symbol.
User- defined
burst shape	up to 256 user- entered values, which define the shape of the curve in the
	specified rise or fall time. The values can vary between 0 (no power) and 1 (full
	power) and are scaled linearly. Once specified, the values are resampled as
	necessary to create the cubic spline that passes through all of the sample points.

The default burst shape of each format is implemented according to the standards of the format selected. You can, however, modify the following aspects of the burst shape:

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