
DS26522 Dual T1/E1/J1 Transceiver
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8.11.3.5
ANSI T1.231 for T1 and J1 Modes
For short-haul mode, loss is declared if the received signal level is 3dB lower from the programmed value (based
on
Table 9-19
) for a duration of 192-bit periods. Hence, if the sensitivity is programmed to be 12dB, loss will be
declared at 15dB. LOS is reset if the following criteria are met:
1) 24 or more ones are detected in 192-bit period with a programmed sensitivity level measured at RTIP and
RRING.
2) During the 192 bits, fewer than 100 consecutive zeros are detected.
For long-haul mode, loss is detected if the received signal level is 3dB lower from the programmed value (based on
Table 9-19
) for a duration of 192-bit periods. Hence, if the sensitivity is programmed at 30dB, loss declaration level
will be 33dB. LOS is reset if the following criteria are met:
1) 24 or more ones are detected in 192-bit period with a programmed sensitivity level measured at RTIP and
RRING.
2) During the 192 bits, fewer than 100 consecutive zeros are detected.
8.11.3.6
ITU-T G.775 for E1 Modes
For short-haul mode, loss is declared if the received signal level is 3dB lower from the programmed value (based
on
Table 9-19
) for a duration of 192-bit periods. Hence, if the sensitivity is programmed to be 12dB, loss will be
declared at 15dB. LOS is reset if the receive signal level is greater than or equal to the programmed sensitivity
level for a duration of 192-bit periods.
For long-haul mode, loss is detected if the received signal level is 3dB lower from the programmed value (based on
Table 9-19
) for a duration of 192-bit periods. Hence, if the sensitivity is programmed at 30dB, loss declaration level
will be 33dB. LOS is reset if the receive signal level is greater than or equal to the programmed sensitivity level for
a duration of 192-bit periods.
8.11.3.7
ETS 200 233 for E1 Modes
For short-haul mode, loss is declared if the received signal level is 3dB lower from the programmed value (based
on
Table 9-19
) continuous duration of 2048-bit periods (1ms). LOS is reset if the receive signal level is greater than
or equal to programmed sensitivity level for a duration of 192-bit periods.
For long-haul mode, loss is declared if the received signal level is 3dB lower from the programmed value (based on
Table 9-19
) continuous duration of 2048-bit periods (1ms). LOS is reset if the receive signal level is greater than or
equal to the programmed sensitivity level for a duration of 192-bit periods.