Moving forward – an in-depth look at LTE technology

Unless you’ve been living under a rock, you must have heard about 4G and maybe even some of the flavors it currently comes in – LTE, WiMAX, or HSPA+. These three wireless standards are what the four major U.S. carriers use to deliver high speed internet connectivity to their 4G-enabled mobile devices. Verizon was the first U.S. carrier to devote itself to LTE, AT&T and T-Mobile rely on HSPA+ for now, yet a shift to LTE is on their agendas, and Sprint is still stuck on WiMAX. In this article, we will be pointing the spotlight at LTE as it seems to be on its way to quickly becoming the most widely adopted 4G technology worldwide.

So what is LTE all about?

LTE stands for Long Term Evolution and is a technology developed by the 3rd Generation Partnership Project (3GPP) – the same folks that introduced 3G mobile internet connectivity via UMTS at a time when EDGE was still considered cutting edge. It is about delivering next generation internet speeds on mobile devices while being just as cost-efficient as its present day counterparts. The need for a transition to a new technology has become eminent since new smartphones and tablets get activated every day and suck more and more of their respective carrier’s wireless data bandwidth. Here is where 4G networks come to the rescue. LTE is a much more efficient standard in comparison to today's widespread 3G networks. It is capable of providing wireless service to a greater number of subscribers within a given area while having a wider signal coverage compared to a current 3G network. Furthermore, LTE is designed to make the most out of the spectrum that it is running on without the need for overly sophisticated equipment.

How efficient is LTE exactly?

One of the key advantages of LTE is that it has been fine tuned for heavy data traffic over IP. It allows for voice calls and data communications to be established at the same time, thus omitting the need for a complicated circuit-controlled voice link – something that 3G networks have to use. Furthermore, LTE technology can dynamically control the amount of bandwidth it is running on in order to suit data demands or the carrier's network configuration. 3G and HSPA networks are hardwired to using 5 MHz of spectrum per channel, while LTE can use as little as 1.25 MHz, or occupy as much as 20MHz per channel. This grants carriers superior control over their networks and makes for more efficient radio frequency usage.

What kind of evolution is LTE’s name implying?

In simple words, it is raw speed where LTE excels in and what puts it so far ahead of its predecessors. Besides boasting an impressive latency time of less than ten milliseconds, which is about four times better compared to current 3G networks, LTE technology is capable of exceeding 100 Mbps peak downlink speeds and 50 Mbps uplink speeds, at least theoretically. Our real life benchmarks (here and here) did not quite make it that far, but to reach such milestones is going to take some time and development, hence the name Long Term Evolution. The great thing is that over time, as LTE technology and the carriers’ infrastructure evolve, the road will be paved for future standards like LTE-Advanced along with data-hungry services such as high-quality video calling and HD multimedia streaming.

What is LTE-Advanced supposed to be?

LTE-Advanced is expected to be launched after LTE's firm establishment as a nationwide 4G network. Technically, until recently LTE did not really have the right to call itself a 4G network – it was LTE-Advanced which was the candidate for the sought-after title. In December of 2010, the International Telecommunications Union – the folks who are responsible for deciding which standards are 4G and which are not, stated that LTE, WiMAX, and HSPA+ will be considered as 4G technologies from then onward. This is one of the reason why every U.S. carrier started boasting a 4G network all of a sudden, even though T-Mobile and Sprint had already started marketing their wireless internet services as being “4G.”

The ITU had previously established its requirements for a “true” 4G network, and they were pretty steep, to say the least. In order to be classified as 4G, a wireless technology had to be capable of delivering peak stationary speeds of 1 Gbps – something that LTE will not be capable of. LTE-Advanced, however, will be designed to meet ITU's requirements, but until the deployment of such wireless standard becomes possible, a bigger amount of radio spectrum is going to be required – something, which is very likely to happen before the decade is out.



I’ve heard this before. Doesn't Obama have something to do with that?

That is correct. When the U.S. government initiated the nationwide transition from analog to digital TV broadcasts, it became clear that the spectrum around the 700 MHz range would become unoccupied soon. Eventually, the frequency band got put up for auction by the FCC – Verizon acquired the lower bands while AT&T obtained parts of the higher frequencies. Both carriers intended to use the newly purchased spectrum for LTE deployment, but it was Verizon that got there first.

However, president Obama’s most significant impact on wireless internet connectivity has to be the approval of a plan, which was heavily influenced by proposals from the FCC to free up 500 MHz of wireless spectrum over a period of ten years in order to meet the rising demand for wireless data. If such a plan becomes a reality, we may witness an increase in 3G and 4G data throughput of anything from 20 to 45 times in comparison to levels from 2009 – a recipe for a potential LTE revolution.

I want LTE and I want it now!

Good for you! 4G LTE USB modems have been available for a while and offer wireless broadband connectivity for your laptop while you are on the move. If you fancy a smartphone, however, you can check out the HTC ThunderBolt – Verizon's current 4G flagship and the carrier's first ever LTE-enabled device. Big Red promises that its LTE services will be available in at least 147 cities throughout the U.S. by the end of 2011 accompanied by a nice selection of LTE-capable devices.

AT&T is expected to launch its first LTE smartphones in the second half of 2011 while at the same time it promises to deliver wireless data cheaper than anyone else. If the acquisition of T-Mobile receives regulatory approval, AT&T will also take advantage of the 1700 MHz spectrum, which T-Mobile's HSPA+ currently occupies, along with the 700 MHz radio frequency that it currently has control over.

It is rumored that even Sprint is about to drop WiMAX in favor of LTE – a move that may prove essential to its survival, yet for now nothing is sure about the future of the nation's third largest carrier. WiMAX technology is slowly becoming an underdog in the battle for 4G dominance and may eventually fade away from the national radio spectrum. Well, whatever the future may bring, it is certain that LTE is here and that it is here to stay. May the force of LTE be with you, dear reader!