Cisco GS7000, Инструкция по установке и эксплуатации

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Enhanced Digital Return System Overview
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EDR Receiver Module
At the receive end, typically in a large hub or headend, the EDR Receiver module
receives the optical signal and performs the conversion back to the baseband data
stream. The resulting data streams are converted back to analog reverse path signals
for routing to termination equipment. The EDR Receiver module is available in the
High Density form factor. The receiver OPMs are available in Standard Range (SR)
and Extended Range (XR) configurations. Both configurations feature a dual LC/PC
optical input connector that feeds two independent reverse optical receivers, each
with its own RF output port.
A single EDR Receiver module occupies one slot in a Cisco Prisma II XD chassis.
Two EDR HD receiver modules can be vertically stacked in an associated Prisma II
Host Module that occupies a single-wide slot in the Prisma II standard chassis. Up to
26 HD modules can operate in a standard 6 rack unit (6RU) chassis (the 56-connector
version of the chassis is required to make use of both receivers in one chassis slot).
Up to 16 HD modules can operate in the Prisma II XD chassis. The ability to mix
EDR Receiver modules with other Prisma II HD modules in the same chassis greatly
enhances the flexibility of the platform.
For instructions on installing the receiver refer to the Prisma II Chassis Installation
and Operation Guide , part number 713375.
The following block diagram shows the receiver module's internal components.
At the headend, the reverse optical receiver converts the optical signal back to an RF
signal that is then routed out through the receiver's RF output.
Refer to the Cisco Prisma II EDR Receiver Installation Guide , part number
OL-29646, for detailed information on the EDR receiver module.