Unlicensed LTE, otherwise known as LTE-U and more recently known as LAA (Licensed Assisted Access) has attracted a bit of debate in recent times. This, largely seems to be due to the dependency Wi-Fi has on unlicensed spectrum. For background, unlicensed spectrum is exactly what the name suggests it is. It refers to spectrum which is not officially licenced to anyone and instead operates as more of an open and anyone-can-use type deal. As they are not licenced to anyone, from the carriers perspective they are considered to be a perfect playground to facilitate their already licensed LTE spectrum. This is exactly what some carriers are intending to do. By using unlicensed spectrum (typical 3.5 and 5 GHz bands) to prop up their own networks, they can somewhat help to alleviate pressure in more congested areas. LTE-U enabled smartphones will be able to utilize these lesser used spectrum when needed and provide respite for the licensed spectrum.
However, some parties are worried about this seemingly eyeing up of the unlicensed spectrum by carriers. This is because Wi-Fi depends on these low band spectrum to provide Wi-Fi signals to the many Wi-FI users. Those concerned are worried that LTE-U enabled smartphones will simply eat up the spectrum forcing Wi-Fi users to receive a lesser product. Well, today at MWC, Qualcomm's CTO, Matt Grob took part in an interview to try and alleviate some of the concerns people might be having with LTE-U. In fact, Grob was not only looking to alleviate concerns but also wanted to explain that he believed LTE-U can perfectly co-exist with WiFi and in some cases, will help to supplement Wi-Fi.
Grob's arguments on the matter is simple. The reason carriers are interested in LTE-U is that there is nobody using the unlicensed spectrum. As such, the intention is, to use LTE-U devices in channels where no one else is using it. Therefore, not impacting on anyone, including Wi-Fi users. Not to mention, Grob suggests LTE-U devices will have a 'listen before talk' function built-in, which essentially will stop the device transmitting when it registers any traffic (i.e. Wi-Fi). Grob goes on to liken the idea of LTE-U and Wi-Fi sharing the same unlicensed spectrum, to that of Wi-Fi 802.11 a/b/g and 802.11n sharing the same space. Grob's logic is that 802.11n did not replace 802.11 a/b/g, but instead the former helps to facilitate the latter. In much the same way, Grob predicts that as Wi-Fi evolves and its capabilities increase much more in line with LTE, the additional LTE-U bands will be of benefit to Wi-Fi and not a hindrance. Either way, Qualcomm is in the process of producing these LTE-U enabled chips and believes they will likely be introduced in smartphones as easily as next year, with the chips being available to manufacturers late 2015.