Optical Output; Transmitter Block Diagram - Cisco Prisma II HD-LRMW Installation And Operation Manual

Chapter 1 Introduction
to the incident RF power. A controller monitors this voltage level to evaluate
the input power level. The transmitter generates an alarm condition if the
input power is over or under a specified level.
The amplified RF signal is also routed to a variable attenuator, which is used
to reduce RF power in an overdrive condition or compensate for gain
variations in the transmitter. The signal is equalized, impedance-matched,
and then sent to the laser. The optical output connector is located on the front
panel of the module.
Transmitter gain is controlled through the selection of Manual or Automatic
Gain Control (AGC) mode operation.
In Manual mode, an attenuator can be used to reduce RF power in an overdrive
¾
condition or to compensate for variations in transmitter gain. Any manual
attenuator adjustments are reflected in the indicated RF drive level. It may be
desirable to make such adjustments to compensate for power differences if the
channel load differs from the specified value.
In AGC mode, the microprocessor monitors the actual input composite power
¾
and adjusts the attenuator to maintain constant RF drive level into the laser
diode.
After the RF amplification and control stage, the signal is equalized and
impedance-matched, and then is sent to the hybrid laser/modulator. The
optical output connector is located on the front panel of the module.
The user can turn the laser on or off, adjust the drive level to the laser, and set
alarm levels. The module can be controlled either locally using LCI, the ICIM
front-panel interface, or remotely using CLI commands or the ICIM Web
Interface.

Optical Output

The optical output connectors are SC/APC.
WARNING:
Avoid damage to your eyes! Do not look into any optical connector while the
system is active. Even if the unit is off, there may still be hazardous optical
levels present.

Transmitter Block Diagram

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