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OM-2000 Out-of-Band Multiplexer/ Modulator
The OM-2000 produces an out-of-band data stream to digital set-tops providing a signaling channel, transmission of program guide information, code downloads, infrared codes, application information, and the downstream path in an interactive system. Data input is configurable through Ethernet and serial connections. Its Quadrature Phase Shift Key Modulator (QPSK) modulates data on a 1.5 MHz wide carrier in the 71 - 129 MHz band with transmitted data multiplexed either in the OM-2000 or externally. Null packets are used as necessary to perform rate aggregation between its inputs and the 2.048 Mbps output. Forward Error Correction (FEC) encoding and interleaving protects data integrity.
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