& cplSiteName &

Setting the Stage for Docsis 3.1

Technically Speaking With SCTE
Technically Speaking With SCTE
Technically Speaking With SCTE
11/16/2012
50%
50%

4:10 PM -- There were any number of things that turned heads at Society of Cable Telecommunications Engineers (SCTE) Cable-Tec Expo last month, but the biggest attention-getter might have been the special session that pulled the covers back on the upcoming Docsis 3.1 spec.

In front of a standing-room only crowd, representatives of CableLabs , major MSOs and SCTE discussed what the new spec would mean for the industry and the steps operators need to take to accelerate deployment. (See Docsis 3.1 Set for a Spring Fling and Docsis 3.1 Targets 10-Gig Downstream.)

Once again, cable engineers are faced with the need to leverage the flexibility and the limits of HFC (hybrid/fiber coax) networks to create higher capacities, faster speeds and -- most important -- more satisfied customers. Docsis 3.1 promises to usher in a whole new era for HFC plant that includes significantly higher performance and greater cost effectiveness.

So what's all the excitement about? There are three key areas in which Docsis 3.1 signaling will be markedly different from its predecessors:

  • Using a higher order of modulation, for greater spectral efficiency, could conceivably add at least 25 percent more capacity and up to 50 percent more over the same HFC network. Note that the proposed DVB-C2 specification in Europe has been tested to support 4096 QAM downstream within existing cable networks.

  • A new modulation format, Orthogonal Frequency-Division Multiplexing (OFDM), that takes efficiency and robustness to new levels. OFDM enables sub-carriers to be squeezed directly against one another, eliminating the need to use valuable RF spectrum as guard bands. At the same time, the longer symbol durations of the sub-carriers make OFDM more capable of dealing with impulse and burst noise than are SC-QAM guard bands.

  • The use of Low Density Parity Check (LDPC) coding to improve noise immunity by several dB over current Reed-Solomon encoding at similar channel efficiency, or to provide greater channel efficiency at the same MER (modulation error ratio).


What does all this mean for cable engineers? Nothing that we haven't proven that we could do in the past. We'll need to tighten our networks further and eliminate ingress and impairments that can impact performance. And to deliver our ultimate objective -- 10Gbit/s downstream by 1Gbit/s upstream -- we'll need greater RF spectrum (1.2GHz to 1.5 GHz downstream, and 200MHz to 400 MHz upstream), but this is far less than would have been required without the other improvements in signaling.

To ensure that engineering teams are aligned with the timing and details of the Docsis 3.1 spec, SCTE has created an HFC Readiness for Higher Order Modulation working group. Under the leadership of Motorola Mobility Technical Fellow Jack Moran, a seasoned Docsis and RF plant engineer, the working group will be creating recommended practices documents that will complement updated SCTE measurement recommended practices and Docsis training. (See SCTE Rallies Around Docsis 3.1.)

Our special session on Docsis 3.1 was a big hit at SCTE Cable-Tec Expo. SCTE and CableLabs are working together to ensure that the real thing lives up to its advance billing.

— Daniel Howard, SVP, Engineering & CTO, Society of Cable Telecommunications Engineers (SCTE)

This is the latest installment of "Technically Speaking with SCTE," a monthly blog of interviews and columns to provide Light Reading Cable readers with timely updates on the SCTE's initiatives and activities.

(2)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
Duh!
50%
50%
Duh!,
User Rank: Light Sabre
12/5/2012 | 5:17:32 PM
re: Setting the Stage for Docsis 3.1


LDPC = Low Density Parity Check (not Power).  AKA Gallager Codes, after their inventor, Bob Gallager.  That it is now practical to approach the Shannon Limit at these kinds of rates is a testament to Moore's Law.


Jack Moran is a terrific choice for chairman of the HFC Readyness working group.  Jack is an engineer's engineer, with decades of experience driving standards.   I doubt that anybody has more in-depth knowledge of the HFC physical media and transmission impairments.  He's definitely one of the good guys.


 

Jeff Baumgartner
50%
50%
Jeff Baumgartner,
User Rank: Light Beer
12/5/2012 | 5:17:31 PM
re: Setting the Stage for Docsis 3.1


Yep, "parity," not "power"... thanks, should've caught that typo. JB

Featured Video
From The Founder
Light Reading is spending much of this year digging into the details of how automation technology will impact the comms market, but let's take a moment to also look at how automation is set to overturn the current world order by the middle of the century.
Flash Poll
Upcoming Live Events
October 18, 2017, Colorado Convention Center - Denver, CO
November 1, 2017, The Royal Garden Hotel
November 1, 2017, The Montcalm Marble Arch
November 2, 2017, 8 Northumberland Avenue, London, UK
November 2, 2017, 8 Northumberland Avenue – London
November 10, 2017, The Westin Times Square, New York, NY
November 16, 2017, ExCel Centre, London
November 30, 2017, The Westin Times Square
May 14-17, 2018, Austin Convention Center
All Upcoming Live Events
Infographics
With the mobile ecosystem becoming increasingly vulnerable to security threats, AdaptiveMobile has laid out some of the key considerations for the wireless community.
Hot Topics
The Big Cable DAA Update
Mari Silbey, Senior Editor, Cable/Video, 10/11/2017
Is US Lurching Back to Monopoly Status?
Carol Wilson, Editor-at-large, 10/16/2017
Pai's FCC Raises Alarms at Competitive Carriers
Carol Wilson, Editor-at-large, 10/16/2017
DT: Brutal Automation Is Only Way to Succeed
Iain Morris, News Editor, 10/10/2017
Telecom Italia Covers 73% of Italy With NB-IoT
Iain Morris, News Editor, 10/13/2017
Animals with Phones
Live Digital Audio

Understanding the full experience of women in technology requires starting at the collegiate level (or sooner) and studying the technologies women are involved with, company cultures they're part of and personal experiences of individuals.

During this WiC radio show, we will talk with Nicole Engelbert, the director of Research & Analysis for Ovum Technology and a 23-year telecom industry veteran, about her experiences and perspectives on women in tech. Engelbert covers infrastructure, applications and industries for Ovum, but she is also involved in the research firm's higher education team and has helped colleges and universities globally leverage technology as a strategy for improving recruitment, retention and graduation performance.

She will share her unique insight into the collegiate level, where women pursuing engineering and STEM-related degrees is dwindling. Engelbert will also reveal new, original Ovum research on the topics of artificial intelligence, the Internet of Things, security and augmented reality, as well as discuss what each of those technologies might mean for women in our field. As always, we'll also leave plenty of time to answer all your questions live on the air and chat board.

Like Us on Facebook
Twitter Feed