LTE Focus Puts Pressure on Femtocells

Equipment vendors' focus on finalizing Long-Term Evolution (LTE)/Systems Architecture Evolution (SAE) standards specifications by the end of 2008 has raised concerns that femtocell standards work, which also faces a tight deadline, could suffer as a result.

Both LTE/SAE and femtocells -- or, Home Node Bs in 3rd Generation Partnership Project (3GPP) terminology -- have a deadline of around December this year for their specifications to be included in the next 3GPP release, Release 8. It's a critical target for both technologies. (See LTE Specs on Track.)

Given the weight of influence behind LTE/SAE, not everyone is convinced that femtocells will meet that December cutoff.

"Yes, there is a risk [that femtocell standards work could slip]… We need more contributions from vendors," says Zhongrong Liu, head of RAN strategy at T-Mobile International AG . "Now a number of big vendors have more attention on femtos. Nevertheless LTE/SAE standardization is of course the big issue for them," Liu tells Unstrung.

Despite the greater focus on so-called 4G technology LTE, other industry sources close to the standardization process believe the femto specs will be developed enough to be included in the initial Release 8 draft, even if they're not completed.

Any changes required after the "freeze" date, scheduled for December, would be done in a controlled way.

But it's possible that not all of the functionality will be included as originally intended, and that some planned specifications work would need to be deferred to the next standards release, due one year later.

Some femtocell executives aren't concerned that some details might miss this year's deadline, as the specs work in question isn't vital for initial home base station deployments.

"The main focus of the work at risk of not being completed in Release 8 relates to femtocell optimizations for future [Release 8 compatible] handsets," says Andy Tiller, vice president of marketing at ip.access. "The initial focus of the femtocell market, on the other hand, is support for handsets that are already in the market today. All the pieces we need for this will be in place in Release 8, so any omissions will not affect the viability of the early femtocell market," only the rate at which more elegant, optimized solutions are developed, adds Tiller. (See Cisco, ip.access Prep Femto Combo.)

But a lot is at stake for femtocells. Operators stress the need for standardized femto equipment, or at least a clear view of how vendors will support a standard in their equipment, before they can even consider large-scale deployments. A holdup in the standards would delay this new home base station market. (See Operators Feel Femto Frustration.)

It's not hard to see how infrastructure suppliers would struggle to meet all the standardization demands for these two technology groups and how their resources could be stretched at the 3GPP. The next 3GPP release is chock full of other important technologies, in addition to femtos and LTE, such as those related to HSPA evolution and mobile IP core.

On one hand there is LTE/SAE, an entirely new radio access technology, and mobile core, which has some of the world's biggest operators backing it as their so-called 4G next-generation infrastructures, with some carriers, such as Verizon Wireless , Vodafone Group plc (NYSE: VOD), China Mobile Communications Corp. , and NTT DoCoMo Inc. (NYSE: DCM), already talking about commercial deployments. (See DoCoMo Takes LTE to 250 Mbit/s, China Mobile Joins LTE Threesome, MWC Preview: LTE in the Limelight , LTE Hits 300 Mbit/s, and AT&T & Verizon Make 700 MHz Plans.) On the other hand, those same influential carriers are eager to put femtocell technology in their networks to see if the home base stations can live up to the promises of providing cost savings, capacity increases, churn reduction, and future new revenues, all without provisioning problems and economic subsidies. (See Femtos Turn to DSL for Provisioning Smarts , Vodafone Dreams of Metro Femto, Telecom Italia Eyes Femtos, Vodafone Eyes Femto Service This Year, T-Mobile Bets on Ubiquisys, Verizon Checks Out Femtos, and Vodafone, O2 Test Femtocells.)

"There is a strong requirement to meet deadlines for LTE," says Erik Ekudden, vice president and head of standardization and industry initiatives at Ericsson AB (Nasdaq: ERIC). "That cannot be compromised… [But] femtocells also have priority," he said, adding he doesn't see that today's femtocells standards will slip, but it has to be watched carefully.

The next plenary meeting of the Femto Forum Ltd. in September in Bangkok will be crucial for vendors to reach a consensus on some of the details in the Home Node B standard. Progress has already been made with the agreement on the Iu-h protocol for the link between the femto access point and femto gateway. (See Vendors Unite on Femtocell Architecture, 3GPP Picks Femtocell Standard, Ubiquisys Supports Standard, Kineto Supports HNB, and RadioFrame Slams Kineto Claims.)

"We have so far agreed on the majority of what goes with this interface, but further elements in the protocol stack have to be decided," says Malek Shahid, senior manager of femtocell products at Alcatel-Lucent (NYSE: ALU), who coordinates the vendor's standardization work. "We're finetuning the details, and hopefully these will be ratified by December this year." — Michelle Donegan, European Editor, Unstrung

stephencooke 12/5/2012 | 3:35:34 PM
re: LTE Focus Puts Pressure on Femtocells Hi,

The last I heard was that cell-to-cell snychronization was not good enough to guarantee call handoff due to the DSL pipe having too much latency. Is this still the case?

Also, my understanding was that LTE and femtocells were to provide up to 100 Mb/s to a handset while using DSL as the backhaul. Other than Bonded DSL Rings by GTS, I haven't seen any DSL "solution" that can provide the necessary bandwidth in a big enough coverage area to make any sense. It is also important to note that this wireless backhaul traffic has to contend with the home owner's wired Internet and IPTV traffic. I just can't see it at the moment.


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