Today's state-of-the-art Docsis 3.0 cable modems are configured with the ability to bond eight downstream channels -- enough for 240 Mbit/s using 6MHz channel spacing that is common in North America. MaxLinear's new cable front-end receivers/tuners -- the MxL265 and MxL267 -- support 16-channel and 24-channel downstream configurations, respectively. A modem capable of bonding 24 channels would support theoretical downstream bursts of 960 Mbit/s in North America, and 1.32 Gbit/s using EuroDocsis 3.0's 8MHz channel spacing. [Ed. note: a couple of years ago there seemed to be some interest in a modem that could bond 32 downstream channels -- enough for bursts of 1.2 Gbit/s in North American cable systems.]
MaxLinear's revelation is interesting because Broadcom Corp. (Nasdaq: BRCM) and Intel Corp. (Nasdaq: INTC) -- the cable industry's two D3 chipset makers -- have not announced next-generation chipsets. Entropic Communications Inc. (Nasdaq: ENTR) will soon be in the Docsis modem silicon game via its acquisition of Trident Microsystems Inc. (Nasdaq: TRID), but has not committed to developing any D3 chips. But MaxLinear's new tuner family offers a good sense of where Docsis 3.0 is heading next. (See Entropic Sweetens Pot to Win Trident .)
MaxLinear is basing the new configurations in direct response to its customers, which include makers of stand-alone cable modems and video set-tops and gateways that embed Docsis 3.0 capabilities, says MaxLinear Marketing Director Jim Koutras.
MaxLinear expects volume production on the new tuners to begin in the third quarter of 2012.
Why this matters
Raw capacity aside, the practical use for these enhanced channel bonding capabilities is for the building blocks for cable's IP video migrations, offering enough headroom for MSOs to comfortably deploy IP video simulcasts.
MaxLinear's new tuners also support an important Full-Spectrum Capture (FSC) capability that lets MSOs pluck channels for bonding from from anywhere up to 1GHz, matching a capability that Broadcom introduced last year. Historically, operators have had to bond channels from a dedicated block of 100MHz, which isn't wide enough to support a 24-channel Docsis 3.0 downstream. FSC also gives MSOs more flexibility in how they manage bandwidth for D3 in relation to other cable services.
- Comcast 'Completes' Docsis 3.0 Rollout
- Broadcom Boots Up 1GHz 'Full-Band' Tuner
- Broadcom Extends Bridge to Cable IPTV
- Comcast Tees Up IP Video Tests
- Cable-Tec Expo: What's the Magic IPTV Number?
- The Ultimate Cable Modem
- Broadcom Dips Two Chips in 800M 'Prototype'
— Jeff Baumgartner, Site Editor, Light Reading Cable