Specifications

A-2
Appendix A
Measurement Definitions
Measurement Definitions
Measurement definitions for the Agilent 71612 Series error performance analyzer are
given in this appendix.
Error Measurements
The error detector counts bit errors by comparing the incoming data bit-by-bit with the
internally-generated reference pattern. Error count and ratio are calculated for three types
of errors: errored ones, errored zeros and all logic errors. All measurements run during the
gating periods as described with the exception of Delta Error Count and Delta Error Ratio.
These measurements run continuously to facilitate user adjustments for minimizing errors.
Error Count
The total number of errors during the gating period.
Delta Error Count
The number of errors in successive decisecond intervals.
Error Ratio
The ratio of counted errors to the number of bits in the selected gating period.
Delta Error Ratio
The ratio of counted errors to the number of bits in successive decisecond intervals.
Errored Intervals
Time intervals during which one or more errors occurred. These intervals are errored
seconds, deciseconds, centiseconds or milliseconds.
Error Free Intervals
Time intervals of seconds, deciseconds, centiseconds or milliseconds, during which no
errors occurred.
Error Analysis
The error analysis is based on CCITT Rec G.821 and is derived from the bit error results.
% Unavailability
The error ratio is calculated over 1 second timed intervals during the gating period. An
unavailableperiodbeginswhentheerrorratioisworsethan1x10
-3
for 10 consecutive
seconds. These 10 seconds are considered part of the unavailable time. The unavailable