Bird Technologies BDS-Manual - Manual (Page 47)

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Arc Detection
Arc Detection is used to identify and report transient events in an RF delivery system. The options available in the
“Arc Detection” page are used to specify an arc event and also instruct the BDS how to store the results.
Figure 20 Arc Detection Dialog
Enable Arc Detection - Turns on and off arc detection.
Sample Rate - Period used for peak/magnitude sampling (down-sampled from actual ADC rate).
Note: Range: 50ns to 4us. Default is 1us (1MHz).
Arc Length - Arc Length defines the maximum window that the trailing edge of an arc "pulse" must occur in. An
arc is detected if it has a pulse width less than or equal to the arc length.
Example - A 400us arc length will detect arcs with pulse widths of 400us, 300us, or less,
but not 401us or 500us. Range is 500ns to 2.044ms (depending on Sample Rate).
Note: Default is 400us.
Trigger Delay - The Trigger Delay parameter determines how the pre/post recording time is set. It is entered in
the BDS GUI as the percentage of the buffer to report after the falling edge of the arc event. The delay equates to a
time based on the sample period.
Example - For the 8-bit ADC with a sample rate of 1us and a Trigger Delay of 75% would
equal 3.072 ms worth of data post-trigger and 1.024 ms worth pre-trigger.
Min ADC Level - Min ADC Level specifies the minimum count level to accept an arc event. This is used to prevent
spurious arc events, especially events reported when measuring the noise floor. The value is entered as a percentage
of full-scale.
Note: Range is 0-100%. Default is 50%.
Note: At least 8% is recommended to avoid false positives while measuring the noise floor.
Power Threshold - The Power Threshold parameter is used to define the minimum pulse amplitude that must be
detected before reporting an arc event.
Note: Thresholds include: 6 dB, 4 dB, 2 dB, & 1 dB. Default is 6 dB.
Example - If the 6 dB level is selected, only pulses with amplitudes of 6 dB or greater over
the base signal are reported as arc events. A 4 dB pulse will not be reported when the 6 dB
level is selected.
Log data to BDS Receiver - This option will log the arc results data to the BDS receiver in non-volatile storage.
The “Arc Data Viewer” can be used to retrieve the data from the receiver after it has been collected.
Note: The “Arc Data Viewer” is launched from the main menu under “Tools-> Arc Data Viewer…”.
Log Data to PC Immediately - This will log the arc results data to a specified folder on your PC upon detection of
a transient event.