It has been long time since we needed a definition given to a form of Internet Service. We hear companies like Verizon Wireless throw around three letter acronyms all the time, and the newest one is LTE. LTE stands for Long-Term Evolution, but its entire name is “3GPP Long-Term Evolution for the Universal Mobile Telecommunications System”. This would actually be 3GPP UMTS LTE. So it is no wonder why wireless firms are marketing the service as simply LTE.
Now that we know what the letters mean what is the service all about. LTE is less a type of Internet service and more a standard in which wireless service can be measured. Another way to look at it would be that LTE replaces what is currently being referred to as 3G networks by T-Mobile, AT&T, Sprint and other Internet Providers. The upgrade from 3G is significant and is exemplified by the Verizon LTE service available in Dallas, Texas. This service has been up long enough to get a broad selection of data that shows definitively that the network offers consistent average downloads of 15 Mbps and an average upload speed of 1.5 Mbps. By way of example the older Verizon 3G network had download speeds around 1 Mbps and could upload at about 0.67 Mbps. This is an enormous leap in service and beats its competitors hands down. AT&T also has an LTE offering; however it has not been in service long enough or with a significant service load to offer enough data to make any determinations on average speeds.
So what does LTE really mean for wireless customers? Remember ads showing iPhone users browsing the Internet while they had a conversation on the same phone? While it is true that this is possible, have you ever tried it? On a 3G network it is absolutely possible to do this but after having tried it I couldn’t recommend it to anyone. The bandwidth on 3G networks that is available to users is simply too narrow to actually enjoy web surfing while on a call. For myself I would say that I don’t enjoy web browsing on my 3G network at all. LTE will change all of this. It is 15 times faster than the 3G network.
How Does LTE Work?
One secret behind the massive technological leap being made by LTE is the use of two separate interfaces, one for uploads and one for downloads. By using separate connections the service can optimize each differently to offer the best service going both ways.
For uploads LTE utilizes, get ready for it, Discrete Fourier Transform Spread Orthogonal Frequency Division Multiple Access or DFTS-OFDMA. This is a mouthful and if you want to know more about this scheme you can visit the Wiley Library and read their PDF report here. The article is so technical that even I had a hard time getting through it so I will summarize what I think is important. The upload scheme of DFT-OFDMA allows the carrier to accept an upload source that is far weaker than the download source. The speed at which data is transferred is of course greatly reduced but so are the power requirements. Imagine if you phone had to send a signal to a wireless tower with the same strength that the tower was sending a signal to your phone. With this “dual channel” set up the data streams can be configured in various ways to make up for the power differential without lowering service quality. In a nutshell your battery will last much longer.
LTE downlinks use Orthogonal Frequency Division Multiple Access or OFDMA. This interface is very different from the wireless connections that have been used since the late 1980’s. In fact the more advanced networks that predate LTE are simply more powerful versions of the same old architecture. OFDMA requires that a “smart antennae” technology called MIMO be used. This is Multiple Input Multiple Output and it allows for more than one connection from a single device. It makes sense that if your phone was using 3 simultaneous connections to a network that it would be faster and more stable. This is the same technology that wireless routers use now and also shatters the future limitations of bandwidth available to consumers. Imagine if the only limitation in upload and download speeds were the device being used.
LTE can be confusing, and with its current limited deployment not much is being done to raise public awareness of how revolutionary the service really is. As the big companies such as Verizon and AT&T begin to aggressively roll this offering out we will begin to hear and learn more. For now LTE is the best public offering of wireless internet or phone service on the market.