Time Warner Cable NYC's QAM Song

In the Big Apple, Time Warner Cable is gearing up to roll out a whole bunch more edge QAM devices, to deliver a whole lot more digital video and data.

“We’ll have one of the most advanced digital cable networks anywhere” when the upgrades are completed, James Manchester, president of network operations and engineering for TWC’s New York region, told me at the company’s DOCSIS 3.0 launch last week.

A QAM (quadrature amplitude modulation) device “imprints” digital information onto RF spectrum. In the past year or so, according to Manchester, the cost of edge QAMs has dropped in half — from $300 per channel to about $150. Harmonic is the division’s key supplier for edge QAMs.

A big project for Manchester’s team is deploying switched digital video, using BigBand’s SDV servers (see Time Warner Cable To Take Switched Video To NYC, LA, Dallas). Manchester said TWC New York will allocate 16 QAMs for SDV, which saves bandwidth by delivering linear TV channels only when a subscriber requests them.

For DOCSIS 3.0, the operator will allocate 4 QAMs with Arris’s C4 CMTS while it will use 5 QAMs with Cisco’s uBR 10K, compared with one QAM for high-speed data previously (see Time Warner Cable Powers Up Wideband In Big Apple). The difference, Manchester explained, is that Cisco’s implementation requires the extra QAM to do load-balancing for DOCSIS 2.0 modems.

Meanwhile, TWC NYC is looking to expand VOD capacity from 4 QAMs today, to 8 QAMs in 2010. The space for all these new QAMs is being freed up in part by migrating analog channels to digital-only distribution.

It’s an example of why MSOs will continue to need increasingly higher densities in their QAM platforms. Note that Harmonic, for one, is working up a “HectoQAM” system that would provide 100 QAMs over a single port (see Harmonic Plans for Unicast Universe).