CES: Broadcom Chips In For DOCSIS 3.1

Broadcom is using this week’s International CES to unveil its first system-on-a-chip based on DOCSIS 3.1, the emerging CableLabs spec that is paving a path toward multi-gigabit speeds over HFC networks.

Broadcom, the first chipmaker to introduce a D3.1-based chipset, unveiled the BCM93390, a modem reference design that also bakes in 802.11ac WiFi radios that, it claims, can also pump out in-home wireless speeds of up to 2 Gbps.

Intel and STMicroelectronics, which is demonstrating DOCSIS 3.1 here at the show, are among the other chipmakers known to be developing DOCSIS 3.1 silicon.

The initial crop of DOCSIS 3.1 modems will be hybrids in that they will also be capable of supporting both DOCSIS 3.0 and DOCSIS 3.1 traffic. The aim there is to provide cable operators with a relatively smooth migration path as they light up fresh DOCSIS 3.1 spectrum.

As for Broadcom’s entry, the company said it complies with the D3.1 specs, meaning it will feature support for two OFDM (orthogonal frequency-division multiplexing) channels that are each 196-MHz wide, two 96 MHz OFDM-A upstream channels, 32 single-carrier DOCSIS 3.0 QAM downstream channels, and 8 single-carrier DOCSIS 3.0 QAM upstream channels.

Broadcom noted that the chip also integrates PacketCable voice and e-router apps, as well as RDK-B, an emerging, unified version of the preintegrated software stack for set-tops as well as DOCSIS-powered broadband gateways. The original version of the Reference Design Kit, which is being managed by Comcast, Time Warner Cable and Liberty Global, supported only hybrid QAM/IP and IP-only video devices.

Broadcom said the BCM93390 DOCSIS 3.1 design is currently sampling, and did not announce pricing or when it expects the SoC to reach commercial availability.

CableLabs, which conducted its first D3.1 interop last month and will host its second one later this month, expects to start official DOCSIS 3.1 certification and qualification testing as early as the second quarter of 2015.

DOCSIS 3.1 is a more efficient platform that aims to support capacities of up to 10 Gbps downstream and at least 1 Gbps upstream by utilizing blocks of OFDM subcarriers and a the introduction of the Low Density Parity Check (LDPC) forward error correction scheme. In addition to paving the way toward cable’s eventual all-IP migration, DOCSIS 3.1 will enable cable operators to deploy gigabit speeds on a broad basis without having to pull fiber all the way to the premises. 

Broadcom’s announcement also shed some light on when some of the world’s largest cable operators expect to start rolling out DOCSIS 3.1.

“The next generation of DOCSIS technology supports the Gigabit speeds our subscribers will increasingly demand over time,” said Balan Nair, Liberty Global’s EVP and CTO, in a statement. “DOCSIS 3.1 will enable Liberty Global to deliver an even richer experience once we begin deploying this cost-effective technology during the second half of 2015.”

“DOCSIS 3.1 is a critical technology for Comcast to provide even faster, more reliable data speeds and features such as IP video to our subscribers’ homes by harnessing more spectrum in the downstream,” added Comcast EVP and CTO Tony Werner. “By more effectively using our cable plant to grow our total throughput, we expect to offer our customers more than 1 Gigabit speeds in their homes in 2015 and beyond.”