System Description - Cisco Prisma II EDR Installation Manual

System Description

The Cisco EDR system is a set of long-haul transport products for CATV reverse
path applications. The system is designed to transport analog reverse path spectra
from hub or headend to hub or headend over optical fiber. Reverse path signals are
typically DOCSIS and DAVIC data.
At the transmitter, one or two analog reverse path signals occupying the 5 - 85 MHz
reverse band spectrum are sampled by an analog-to-digital converter (ADC). A
high-speed serial data stream is constructed by scrambling and framing the data.
This data stream is carried optically over fiber to a remote hub or headend, where
the receiver detects the optical signal and converts it back to a serial electrical signal.
The data is unpacked and sent to a digital-to-analog converter (DAC), which
reconstructs the originally transmitted analog spectrum.
This system consists of an optical transmitter module installed in a Prisma II or
Prisma XD chassis, and an optical receiver module installed in another Prisma II or
Prisma XD chassis at the hub or headend.
CAUTION:
The EDR receiver is designed to work exclusively with EDR transmitters as
part of the Cisco EDR system. Results with other transmitters are not
guaranteed. Do not install Cisco EDR transmitters in any daisy chain with one
or more Cisco EDR receivers.
The receiver module contains two separate optoelectronic receiver circuits. Optical
input is through an OPM connector mounted on the front of the module. The RF
output is through two connectors on the rear of the module.
Each RF output can be attenuated by as much as 10 dB, relative to no attenuation, in
0.5 dB increments. The actual RF output levels of the receiver, attenuated by 20 dB,
can be monitored at a selectable test point on the front panel.
The receiver supports 2:1 configurations in an XD form factor for both Prisma II
(using Host Module) and Prisma XD Chassis. The OPM optical input uses a dual
LC/PC connector and supports all standard reverse bandwidths: 40, 42, 55, 65, and
85 MHz.
When used together with the Prisma II EDR Transmitter module, the receiver
supports two operating modes, Single 2:1 and Dual 2:1. The factory default
operating mode is Dual 2:1; Single 2:1 operation can be selected by the user. For
additional details on these operating modes, see Receiver Operation (on page 7).
Additionally, the receiver can be operated in any of three redundancy modes:
Master, Slave, or Single. When the receiver module is placed in Single operating
mode, both receiver channels in the module will continue to operate even if the
optical input level falls below the major alarm threshold.
OL-32414-01
EDR 85 System Overview
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