QAMLink® DOCSIS®/EuroDOCSIS™ 2.0 Single-Chip Cable Modem

The BCM3349 combines an RF receiver with an advanced QAM and S-CDMA demodulator, an advanced QAM transmitter, a complete DOCSIS 2.0 Media Access Controller (MAC), a 200-MHz MIPS32 communication processor, a 16-bit, 100-MHz SDRAM interface, 10/100 Ethernet MAC with integrated transceiver and MII Interface, and a USB MAC with integrated transceiver.

The QAM receiver directly samples a tuner output with a 11-bit A/D converter and input ACG amplifier. The receiver digitally resamples and demodulates the signal with recovered clock and carrier timing, filters and equalizes the data and passes soft decisions to an ITU-T J.83 Annex A/B/C compatible decoder. The receiver supports variable symbol rate 4/16/32/64/128/256/512/1024-QAM FEC decoding. The final received data stream is delivered in a serial MPEG-2 transport format. All gain, clock, and carrier, acquisition and tracking loops are integrated in the QAM receiver.