Cisco Cisco OptoStar II Reverse Receivers Installationsanleitung
Starting up the Module, Continued
Signal Inspection
•
Check whether the optical input power is between -16 dBm and +2 dBm with
an optical power meter. Make sure the mating surface is clean when testing.
an optical power meter. Make sure the mating surface is clean when testing.
•
Use a DB meter or spectrum analyzer to measure the RF output level of the
module test point, to ensure the appropriate output level in different gain
modes.
module test point, to ensure the appropriate output level in different gain
modes.
1. When the module is in AGC (Automatic Gain Control) mode, the optical
input power is -10 dBm to +2 dBm, with OMI=16%, and the RF output level
is 31dBmV/channel. In the same OMI setting, when the optical input
power is less than -10 dBm or more than +2 dBm, every 1 dB increase (or
decrease) of the receiver input power leads to 2 dBm increase (or decrease)
of the RF output level. For example, when the optical input power is -11
dBm, the output level is 29 dBmV; when the optical input power is +3 dBm,
the output level is 33 dBmV.
is 31dBmV/channel. In the same OMI setting, when the optical input
power is less than -10 dBm or more than +2 dBm, every 1 dB increase (or
decrease) of the receiver input power leads to 2 dBm increase (or decrease)
of the RF output level. For example, when the optical input power is -11
dBm, the output level is 29 dBmV; when the optical input power is +3 dBm,
the output level is 33 dBmV.
2. When the module is in MGC (Manual Gain Control) mode, the attenuation
is 0 dB, and the optical input power is -7 dBm, with OMI=16%, and the RF
output level is 37 dBmV/channel. In the same OMI and MGC settings,
every 1 dB increase (or decrease) of the receiver input power leads to 2 dBm
increase (or decrease) of the RF output level. For example, when the optical
input power is -6 dBm, the output level is 39 dBmV.
output level is 37 dBmV/channel. In the same OMI and MGC settings,
every 1 dB increase (or decrease) of the receiver input power leads to 2 dBm
increase (or decrease) of the RF output level. For example, when the optical
input power is -6 dBm, the output level is 39 dBmV.
If the input signal level is out of the range, the module performance will be
degraded.
degraded.
•
When using a DB meter or spectrum analyzer to measure the RF output level
via the test point on the front panel, the actual value of the output level is 20 dB
higher than the measured value.
via the test point on the front panel, the actual value of the output level is 20 dB
higher than the measured value.
OL-29663-03
Operation
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