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Chapter 1. introduction – Comtech EF Data CDM-760 User Manual

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Chapter 1. INTRODUCTION

1.1 Overview

Figure 1-1. CDM-760 Advanced High-Speed Trunking Modem

The CDM-760 Advanced High-Speed Trunking Modem (Figure 1-1) accommodates Internet

Service Provider (ISP) and Telco backhaul links using advanced space segment saving capabilities

while minimizing the need for unnecessary overhead. The CDM-760’s high-performance

architecture allows efficient networking and transport over satellite links while supporting a

wide range of applications and network topologies.

The CDM-760 offers an expansive, ultra wide range of symbol rates (100 ksps to 150 Msps) and

data rates (100 kbps to 314 Mbps or, when run in a duplex setting, 628 Mbps or 300 Msps).

Coupling these speeds with the native Super Jumbo Frame (SJF) Ethernet interface, the

CDM-760 supports Ethernet frames from 64 bytes to >10,000 bytes, and processes Ethernet

frames >600,000 packets/second, or >1.2 Million packets/second when run in a duplex setting.

DVB-S2 has been widely accepted as one of the most spectrally efficient standards-based

waveforms. Expanding on the efficient DVB-S2 EN 302 307 standards, the CDM-760 furthers

spectral efficiency with its DVB-S2-EB1 and DVB-S2-EB2 Efficiency Boost technology waveforms:

• DVB-S2-EB1 affords a 10% to 35% increase in efficiency over the DVB-S2 standard without

an increase in power or occupied bandwidth. The CDM-760 accomplishes this task by

virtually doubling the number of available ModCods and introducing three new spectral

rolloff (ROF) figures (5%, 10%, and 15%).

• DVB-S2-EB2 further increases throughput for 16APSK and 32APSK constellations and adds

64APSK constellations to the modem.