Zhone Technologies IMACS-200 - Manual (Page 232)

13-2 OWAN Ports
Model No. Running Head
On the transmit signal side, the CMI encoded DS2 or E2 signal is fed into a laser driver from
the CMI encoder. On the receive signal side, the electrical signal is then fed through an digital
multiplexer to the clock recovery circuit to obtain a clean DS2 or E2 signal and reference
clock. The analog multiplexer retransmits to the clock recovery circuit either the received
optical signal or the transmit signal during DS2 or E2 loopback mode. The laser optical output
power is -10dBm, and the receiver system is capable of recovering the signal to -30dBm.
The ports shown below in Figure 13-1 show the two ports on the rear of the box, with the dust
caps removed from OWAN port, ready for optical connectors.
Figure 13-1.Optional Redundant OWAN Port
13.2.2 OWAN Alarms
The OWAN port detects and reports the following alarms:
• LOS (Loss of Signal) An LOS alarm will be declared after 100 microseconds after the
received optical signal level drops below the operational threshold.
• OOF (Out Of Frame) Activated by the loss of frame synchronization.
• EQ FAIL (Optical Transmitter Alarm) Activated when the Laser Diode current exceeds
the threshold, or when optical power level is below the minimum threshold.
• CLK REC (Clock Recovery Loss of Signal)
• OPT LOS (Optical Loss of Signal) Raised when the Optical receiver fails to detect a
signal
• OPT AIS (Optical Alarm Indication Signal) Raised when the Optical unit receives an
Alarm Indication Signal from the far end.
RS-530