Broadcom Corp. (Nasdaq: BRCM) has announced a radical cable tuning architecture that will let MSOs use spectrum more efficiently while also providing the building blocks for a full-fledged IP video migration.

Broadcom calls it Full-Band Capture (FBC), a technique that lets MSOs pluck 6MHz channels from anywhere on the spectrum (up to 1GHz) and apply that capacity toward services like Docsis 3.0, video on demand and switched digital video. As the IP video migration scenario goes, Broadcom envisions the technology living inside hybrid IP/QAM gateways that can pipe video over Docsis.

The approach is more flexible than the way D3 channel bonding is done now, where the channels used for bonding must be located within the same 100MHz-wide block. While that may be OK for groups of eight channels (the current D3 state-of-the-art), it won't work so well when operators start to embark on IP video simulcasts that could require the bonding of 16 or more downstream channels. (See Cable-Tec Expo: What's the Magic IPTV Number? and Broadcom Boots Up 1GHz 'Full-Band' Tuner .)

There's still no consensus on how many channels cable will be looking to bond next -- MSOs are mulling bonding groups of 16, 24 and even as many as 32 channels, notes Jay Kirchoff, vice president of marketing for Broadcom's cable broadband unit -- but technology like FBC will at least give MSOs more options for obtaining those channels.

"We are ... converting the entire 1GHz spectrum to digital," adds Brett Tischler, Broadcom's senior manager of cable set-top box technology. "That opens up the doors for a lot of new things that weren't possible before."

That new flexibility, he says, will ease the pressure on spectrum management by letting MSOs salvage channels for video-over-Docsis services from anywhere instead of from a rigid, more limited frequency block.

Broadcom is adding FBC and a new front end for IP-capable set-top boxes to its Docsis 3.0 chips, starting with the BCM3128 and BCM 3124 systems-on-chip (SoCs) and its BCM3383 Euro/Docsis 3.0 cable gateway. It demonstrated its latest wares last week at The Cable Show in Chicago.

Broadcom's FBC is coming into focus as it comes under increased cable set-top box pressure from Intel Corp. (Nasdaq: INTC), tuning specialist MaxLinear Corp. and Zoran Corp. (Nasdaq: ZRAN), which got deeper into the sector after purchasing Microtune Inc. (See Zoran Targets Broadcom With Microtune Buy , Intel, Entropic Forge Video Gateway Deal , Intel Snares TI's Cable Modem Business and Comcast Confirms Xcalibur Partners.)

— Jeff Baumgartner, Site Editor, Light Reading Cable