Comtech EF Data QAM256 - Manual (Page 10)

QAM256 Digital Video Modulator and Upconverter Introduction
TM077 – Rev. 4.0 1-1
Introduction
1
This chapter provides an overview of the QAM256 Digital Video Modulator and Upconverter. The
QAM256 may be referred to in this manual as “the unit”, or the modulator”.
1.0 Introduction
The Radyne Corporation new DVB-compliant QAM256 Digital Video Modulator and Upconverter
meet all DVB requirements for transmission of digital video over broadband coaxial cable and
microwave radio. The QAM256 features 4 QAM to 256 QAM modulation, 1 - 52 Mbps data rate,
1 - 8 MHz channel spacing, and Reed-Solomon Forward Error Correction. The QAM256
modulator supports output frequency of 35 to 37 MHz or 43 to 44 MHz or 50 to 862 MHz. The
upconverter combines the QAM Modulator and Frequency converter into a 1 Rack Unit (RU)
chassis (1.75” high) which eliminates the need for an additional converter unit. The modulator
also supports field-changeable RS-422 Parallel, DVB Parallel, M2P Parallel, ASI, and other
standard interfaces. Remote Monitor and Control interface is provided through either an RS-485
or Ethernet Remote Port using SNMP protocol.
The QAM256 provides efficient bandwidth utilization for digital video distribution systems.
MMDS, LMDS and Cable Television systems all benefit from this innovative modulator. QAM
modulation solves the problem of providing multiple video and data channels within bandwidth
limitations. The Radyne QAM256 Upconverter has the versatility to adapt to any terrestrial
broadband medium and give system operators full management and control of the available
bandwidth.
The modulator meets the specifications of the ITU-T Recommendation; J.83 Annex A&B
(Telecommunication Standardization of the ITU for Television and Sound Transmission). The
microprocessor-based Monitor and Control (M&C) operates from the front panel or the remote
port.
The Interface Module is a field-changeable module that contains either RS-422, M2P, DVB,
Parallel, ASI, or other standard interface. The interface can accept data in an MPEG-2 transport
format, or as random data.
Figure 1-1. QAM256 Digital Video Modulator and Cable Upconverter Front Panel