Paradise P300 User Manual
Page 103
P300H
P300 Series Modem Installation and Operating Handbook
Page 103
Terrestrial: 1:PCM Bearer CRC
BER monitors: 2:Tx/Drop mux 3:Insert mux
Change, User-Opt, Operation, Terrestrial Menu
PCM Bearer: 1:Bearer CRC
2:E-Bits 3:CRC/Frame Acq'
Change, User-Opt, Operation, Terrestrial, PCM Bearer CRC Menu
6.10.4 Change, User-Opt, Operation, TERRESTRIAL Menu
PCM BEARER CRC
This option is only applicable when the unit is configured for Drop/Insert operation
with a PCM bearer which supports CRC (T1-ESF or G.732). When appropriate
this accesses a sub menu which is discussed in the following section.
TX/DROP BER
The source for the estimate of the terrestrial BER at the Drop Mux may be
selected:
Auto
The selection is made automatically from the most appropriate
source.
FAW
The input BER is estimated from the Frame Alignment Words
(FAW) of the PCM bearer.
CRC
The input BER is estimated from the number of CRC errors (T1-
ESF & G.732 only).
E-Bits
The output BER is determined by counting the E-Bits on the
incoming G.732 signal. On a G.732 link an E-Bit is returned
by the distant equipment when it receives an errored CRC,
ie the incoming E-Bits represent the error rate at the far end
of this modems outgoing G.732 link. Effectively the error
rate on the outgoing link at the far end.
Default:
Auto
RX/INSERT BER
The source for the estimate of the BER from the terrestrial port at the input to the
insert mux may be selected as described above for the Tx/Drop BER. Default:
Auto
6.10.5 Change, User-Opt, Operation, Terrestrial, PCM BEARER CRC Menu
BEARER CRC
This option, only applicable to G.732 Drop/Insert bearers selects if the PCM
bearer has a CRC, the options available are
None/Ignore
or
Process
. Default:
None/Ignore
.
E-BITS
If a G.732 Bearer with CRC set to
Process
as above, then the additional option
to process & return E-Bits is also available, options for what happens when
incoming CRC errors are detected are
No Action
or
Return E-Bit
. Default:
No
Action
.
CRC/FRAME
ACQ'
Again, if a G.732 Bearer with CRC set to
Process
, then the option exists to
implement the strict letter of ITU G.704, and force a re-acquisition of the terrestrial
Drop/Insert frame sync if CRC sync cannot be achieved within 8ms. Options
available are
Normal
or
Reacquire frame if CRC sync lost
. Default:
Normal
.