Cable modem/CMTS

Moto: S-CDMA Starting to Spread

Motorola Inc. (NYSE: MOT) has been preaching the upstream-enhancing properties of S-CDMA (Synchronous Code Division Multiple Access) since buying Terayon Communication Systems in 2007, and now it seems that it's starting to gain some converts. (See Motorola Seals Up Terayon and Motorola to Buy Terayon for $140M.)

Field trials have been proceeding with Cox Communications Inc. since last fall, and Motorola has since begun more trials with an MSO in South America, two in Europe, and one in Asia, according to Floyd Wagoner, director of global product marketing and marketing communications for Moto's Access Networks Solutions division. All of Motorola's major customers are either trialing S-CDMA in the lab or in the field, he says. (See S-CDMA Gets a Sponsor .)

Motorola won't reveal which MSOs are activating S-CDMA, but based on some recent cable modem termination system (CMTS) deployment wins, potential candidates include Guangdong CATV Network Co. Ltd. and Beijing Gehua CATV Network Co. Ltd. of China; Virgin Media Inc. (Nasdaq: VMED) in the U.K.; Jupiter Telecommunications Co. Ltd. (J:COM) of Japan; UPC Broadband in Europe; LG Powercom and Qrix Communications of South Korea; and Taiwan Broadband Communications (TBC).

S-CDMA's claim to fame is its ability to blast through noisy and normally unusable lower portions of cable's upstream spectrum, channels typically in the 5MHz to 16MHz range. S-CDMA opens up that spectrum and increases upstream capacity by 30 to 50 percent, paving the way for faster single-channel Docsis 2.0 upstream speeds or Docsis 3.0 upstream channel bonding. (See Moto Preaches Cable's Upstream Savior .)

S-CDMA has been part of the CableLabs specs since the completion of Docsis 2.0 in 2002, but MSO adoption has been almost nonexistent. Wagoner says that picture's starting to change because Motorola has been able to "operationalize" S-CDMA, thanks in large part to the lab and field work it put in with Cox over a span of about two years. (See A Decade of Docsis .)

That process involved several iterative software fixes and algorithm tweaks on the Broadcom Corp. (Nasdaq: BRCM) burst upstream receiver present in Motorola's 2x8 (two downstream ports, eight upstream ports) CMTS cards to ensure that the chips were given the right "upstream profile" to work in noisy plant conditions.

"We now have a mainstream S-CDMA implementation," boasts Mike Cookish, director of product management for Moto's access networks solutions unit. Arris Group Inc. (Nasdaq: ARRS) and Cisco Systems Inc. (Nasdaq: CSCO), Moto's rivals in the CMTS category, will also support S-CDMA, but Motorola believes its field experience with the technology gives it a time-to-market advantage.

In time for the RX48
Motorola also intends to apply its learnings to the RX48, a dedicated upstream blade that packs 48 ports and slides into the company's flagship CMTS, the BSR64000. There's no telling if the presence of S-CDMA will goose sales for the RX48 right away. Moto still intends to start shipping that card to customers this summer, with volumes ramping up toward the second half of 2010. (See Moto Hones Super-Dense CMTS Blade.)

Cisco and Arris are also working on denser CMTS upstream blades of their own. (See Cisco Aiming to One-Up Cable's Upstream .)

Combining S-CDMA with the RX48 "is going to be critical to begin the addition of upstream capacity," Cookish says.

But Motorola doesn't believe the new card and upstream channel bonding will necessarily go hand-in-hand. Instead, Motorola anticipates that MSOs will leverage the added capacity of the RX48 to deliver faster upstream speed tiers over one Docsis 2.0 channel, making the leap to Docsis 3.0 upstream channel bonding later on.

A small number of MSOs may start trials for upstream channel bonding this year, but many more are expected to give it a shot by 2011, says Brian O’Neill, Motorola's senior marketing manager.

Some are making the jump sooner than that. Japan Cablenet Ltd. began deploying upstream channel bonding last year using the Arris C4 CMTS and a new set of software. (See Japan Cablenet Swims Upstream .)

— Jeff Baumgartner, Site Editor, Light Reading Cable

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