Section 1
Introduction
The Motorola OM 1000 Out-of-band Modulator links the digital headend equipment with the
distribution system by combining the various out-of-band inputs into a quadrature phase shift
key (QPSK)-modulated signal. It converts multiple digital input streams into a RF output signal
for transmission over the cable system.
Figure 1-1 illustrates the OM 1000:
Figure 1-1
OM 1000
TES T
-2 0dB
PO WER
DATA IN
EX T S YNC
PL L E RROR
RF E RROR
FA ULT SUMM
OM 1000
ENT
The OM 1000:
Receives Ethernet User Datagram Protocol (UDP) packets from a controlling processor
Multiplexes downstream data from multiple sources
Provides forward error correction (FEC) encoding of the bitstream, as well as interleaving
and randomization
Provides downstream QPSK-modulated output within the 71 to 129 MHz range
Provides industry-standard Ethernet 10Base-T connectivity for operation, administration,
maintenance, and provisioning (OAM&P)
Performs periodic insertion of internally stored messages
Controls and provides status/alarm reporting using Simple Network Management Protocol
(SNMP)
OM 1000 Installation and Operation Manual