What is 4G LTE?

Modern day 4G networks are based on the LTE (Long Term Evolution) network standard. Telstra launched the first 4G LTE network in Australia in 2011 over the 1800 MHz band.

The key differentiator between LTE and previous protocols is that LTE had an all-IP network architecture. Compared to circuit-switched 2G and 3G, this was a total redesign. Being totally packet-based meant that it had the simplicity and cost effectiveness of ordinary wireless equipment - the technology had become not that much different to WiFi.

Today 4G remains the world's most popular mobile communication system. It has undergone several evolutions since its launch in 2008 to become a provider of multi-gigabit data speeds and high quality voice calls, and special implementations reaching distances beyond 200 kilometres.

Multiple Access
4G LTE logo

The LTE System

4G LTE (Long Term Evolution) or the E-UTRAN (Evolved Universal Terrestrial Access Network), introduced in 2008 under 3GPP Rel. 8, is the radio access component of the Evolved Packet System (EPS) - a purely IP based mobile network standard. As an evolution to 3G UMTS, 4G LTE shares many similarities, such as harmonised frequency bands, but also many substantial technological advancements.

LTE is based on OFDMA (Orthogonal Frequency Division Multiple Access) and in combination with higher order modulation (up to 256QAM), large bandwidths (up to 100 MHz aggregate), and spatial multiplexing (up to 256T256R MIMO) techniques very high data rates can be achieved.

LTE is developed for a number of frequency bands – E-UTRA operating bands- currently ranging from 450 MHz up to 6 GHz. The available bandwidths are also flexible starting with 0.2 MHz up to 20 MHz. LTE is developed to support both the time division duplex technology (TDD) as well as frequency division duplex (FDD).

Resources & Articles

LTE Evolutions

A 4G LTE network can be classed based on the state of its evolution within the LTE standard. As a continuously developing technology, the LTE standard has undergone several releases by it's developer 3GPP.

You can discover more about each evolution by...

4G Frequency Bands

LTE has been developed to operate on paired spectrum for Frequency Division Duplex (FDD), and unpaired spectrum for Time Division Duplex (TDD).

For an LTE radio system to facilitate bidirectional communication, it is necessary to implement a duplex scheme...

Calculating LTE Data Rates

The following document serves to provide a general introduction to how data rates are estimated in LTE. This article can help readers understand how 4G data speeds are calculated at a theoretical level. For the sake of clarity we will simplify and deal with...