Agilent Technologies E1439 manual Triggerdelayactual=0 or 0/16=0 output samples

Using the Agilent E1439

Delay and phase in triggered measurements

trigger_delay = -2 (a pre-trigger delay of 2)

Because the filter_bw is 4 with decimation on, there are 16 input samples for every output sample for a decimation rate of 24

.

trigger_delay_actual=0 (or 0/16=0 output samples)

desired trigger			trigger
signal		actual trigger	level
1	2	3	4

trigger_delay_actual=4 (or 4/16=1/4 output samples)

desired trigger				trigger
		actual trigger		level
1	2	3	4

trigger_delay_actual=8 (or 8/16=1/2 output samples)

desired trigger			trigger
		actual trigger level
1	2	3	4

The phase returned is the phase of the LO at the actual trigger point, not the desired trigger point. The following example illustrates how age1439_phase_actual_get might be used. In this example, the input signal is a sine wave at a frequency of 4 MHz. The module is set up as follows:

frequency_center = 4.5 MHz filter_bw = 4 (2.4 MHz span) filter_decimate = 1 (on) trigger_type = 1 (ADC trigger)

trigger_delay = -32 (a pre-trigger delay of 32) trigger_adclevel = 0

data_type = 1 (complex)

After the measurement is completed, call age1439_delay_actual_get and age1439_phase_ actual_get. In this example, the values returned happened to be:

delay_actual = 16 phase_actual = 19697

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