Thirty-six companies have weighed in on LTE-Unlicensed following the FCC's request for comment last month, some extolling the benefits of the technology, but many warning of the potential for interference with WiFi.
LTE-Unlicensed (LTE-U) refers to running LTE in 5GHz unlicensed spectrum for a speed and capacity boost. Vendors like Ericsson AB (Nasdaq: ERIC) and Qualcomm Inc. (Nasdaq: QCOM) are pioneering the technology for eager operators like Verizon Wireless and T-Mobile US Inc. But much of the industry remains unconvinced -- despite reassurances and lab trials -- that LTE-U won't interfere with the WiFi devices that have been happily occupying the 5GHz band in the US for some time now. (See Ericsson Preps LTE-U for Verizon, T-Mob & SK Telecom, NTT DoCoMo, Huawei Prove LTE-U Works and Why Some Operators Think LTE-U Is Rude.)
In Europe, it is mandated that LTE-U include a listen-before-talk (LBT) protocol from 3rd Generation Partnership Project (3GPP) 's LTE Release 13, which would ensure that the two networks play nice, This, the Licensed-Assisted Access (LAA) variant of LTE-U, is not required in the US, South Korea, China or India, causing many to fear that early deployments here won't bother to respect WiFi at all. (See Qualcomm Brings LTE-U to Small Cells .)
That is why the Federal Communications Commission (FCC) put out a public notice detailing its concerns on the technology and requesting industry comments. The comment period ended on June 11, with 36 companies, individuals or groups contributing feedback. The FCC is expected to suggest rules and regulations soon, based on this feedback. (See T-Mobile Expects LTE-U to Feature Listen-Before-Talk.)
Most of the comments filed with the FCC recognized the benefits of LTE-U -- spectral efficiency, faster speeds and cost-effective capacity gains -- but also expressed concerns that it had to be implemented fairly and without harming operators' existing investments in WiFi. Many also called on the FCC to leave it to the standards groups to figure it all out.
Here is a sampling of the comments the FCC received on the matter:
- AT&T Inc. (NYSE: T): The carrier hasn't been as vocal on LTE-U as its US competitors, but noted the benefits of LTE-U and said that the FCC should make any decision on LTE-U from a technology neutral point of view. It also discussed the somewhat hazy distinctions between LTE-U and LAA and said that clear definitions are needed this early in the game, but that the standards bodies should be in charge of resolving any interference issues.
- Google (Nasdaq: GOOG): The WiFi proponent took a more negative view of LTE-U, noting the interference potential and degradation of WiFi that might result. "In order to maintain the balanced spectrum policy that has benefited innovators, entrepreneurs, businesses and consumers, the Commission should be vigilant in ensuring that deployments of LTE-U and LAA in unlicensed spectrum will not systematically exclude unlicensed-only technologies," Google wrote.
- Ruckus Wireless Inc. : WiFi hotspot operator Ruckus expressed concerns that pre-standard LTE-U implementations will have "a potentially devastating effect on 802.11-based WiFi networks, especially for services such as voice and video over WiFi." It also noted that despite what LTE device and infrastructure vendors have suggested, it doesn't think LTE-U will be possible through software updates alone, but rather will require new access points to implement it. (See Why Some Operators Think LTE-U Is Rude.)
- Cablevision Systems Corp. (NYSE: CVC): The cable operator, which has a huge WiFi footprint installed, said in a 21-page filing that "LTE-U/LAA proponents have distorted the historical, healthy dynamics of the unlicensed bands, using their FCC licenses to unjustly and unreasonably exploit unlicensed spectrum, harm consumers and undermine an essential input for their competitors." It called on the Commission to work with standards groups to ensure there is effective sharing in the unlicensed band or "step up" to protect consumers and competition. (See Cablevision's New WiFi Try – Freewheeling Enough?)
- Verizon Communications Inc. (NYSE: VZ): The US wireless operator has been more vocal about its support of LTE-U and said in its filing that it's an important technology to meet consumers' skyrocketing data demands. There is no reason for US operators to wait for LAA, it said, because features being developed for LAA are not relevant to LTE-U here, including that LTE-U only supplements downlink, whereas LAA is for uplink and downlink. (See Verizon Focuses on Cashing In on LTE.)
In addition, Light Reading caught up with Broadcom Corp. (Nasdaq: BRCM), which also filed comments with the FCC, last month. Mike Hogan, the chip vendor's Senior Director, Small Cell & Fixed Wireless Access, told us that -- regardless of what the FCC recommends -- he believes LTE-U will take a lot longer to come to fruition than some operators are hoping. LAA may be ready by the time they are anyway.
"I think you have to be careful about what carriers aspire to do and what really happens," Hogan said. "It's one thing to take a public position and say they'll do it versus whether it pans out in volume shipments. What happens quite often in these debates is, you may wind up accelerating existence of robust, fair, 3GPP-approved LAA specs because of the presence of these LTE-U threats and statements by operators. It's more likely it will just accelerate LTE-LAA rather than create a market for LTE-U."
— Sarah Thomas, , Editorial Operations Director, Light Reading