Chapter 2 • Subsystems
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Closed loop timing
The CLT feature provides timing adjustment feedback to enable
the satellite router to transmit as close as possible to the middle of
the burst aperture.
For more information see
Closed loop control
on page 65.
Timing subsystem physical
constraints
A timing generator supports:
•
Ten 10 MHz coaxial connectors thereby supporting up to 8
DVB modulators or ACP systems. Two per outroute and one
per ACP system (if added) are required.
•
Eight DNCCs.
•
Six timing VSATs.
Downlink subsystem
The HX gateway can be configured with one or more inroutes.
Each inroute is a time-division multiple access (TDMA) return
channel. The inroute subsystem manages the return channels
associated with a group of satellite routers.
This system release features the introduction of the CDS, which
replaces the IFSS-TC in newer systems.
Configurable Demodulation
Subsystem
The CDS is a powerful digital signal processor that demodulates
one or more carriers, performs error corrections, and forwards the
resultant bursts to a NOC component.
A CDS consists of a single cardset, configurable demodulation
decoder module (CDDM) and configurable demodulation
interface module (CDIM). The CDS is hosted on a CompactPCI
(cPCI) chassis, along with a host control processor (CP) that is
connected to the dynamic network control cluster (DNCC)
through a LAN interface. The DNCC interfaces with the NOC
components via multiple LANs. The CDS receives inroutes from
the RF equipment and timing from the timing components. The
inroute bursts are processed by the CDS (demodulated and
decoded) and passed on to the DNCC. After converting inroute
bursts into IP packets, the DNCC passes the inroute traffic onto
the final destination, such as the corporate LAN or the Internet
via the internet protocol gateway (IPGW).
The CDS is completely compatible with DNCCs that interface
with Aurora return channel CPs.
One CDS platform can handle up to 9 inroutes, which can vary
based on whether a type 1 or type 4 board is used, across a
frequency band up to 36MHz wide, in a single 1U chassis.
The term CDS can refer to one or more instances of the CDS
platform.
Summary of Contents for HX System
Page 1: ...1037852 0001 Revision A September 4 2008 HX System System Overview Release 1 2 7 ...
Page 8: ... Contents viii 1037852 0001 Revision A ...
Page 10: ... Figures x 1037852 0001 Revision A ...
Page 12: ... Tables xii 1037852 0001 Revision A ...
Page 24: ...Chapter 1 Overview 12 1037852 0001 Revision A ...
Page 26: ...Chapter 2 Subsystems 14 1037852 0001 Revision A Figure 3 HX Subsystems and LAN Connections ...
Page 50: ...Chapter 4 Network security 38 1037852 0001 Revision A ...
Page 62: ...Chapter 5 Bandwidth management 50 1037852 0001 Revision A ...
Page 70: ...Chapter 6 IP features 58 1037852 0001 Revision A ...
Page 80: ...Chapter 8 Transmission features 68 1037852 0001 Revision A ...
Page 88: ...Chapter 10 HX options 76 1037852 0001 Revision A ...
Page 96: ...Appendix B Transportable Gateway TGW 84 1037852 0001 Revision A ...
Page 100: ... Acronyms and abbreviations 88 1037852 0001 Revision A ...
Page 106: ... Index 94 1037852 0001 Revision A ...