Today’s LTE, LTE-A (advanced), and LTE-A Pro are all part of the 4G LTE ecosystem that will serve as a stepping stone to 5G. According to a June 2017 “State of LTE” report from OpenSignal, although the industry is turning its attention toward the 5G network, there is still plenty of activity surrounding LTE. In reports from 2018, OpenSignal showed the continued improvements in coverage and speed for LTE. As 5G improves and reaches its full potential, it will rely on these LTE variants.
LTE-A, LTE-A Pro — and Gigabit LTE in particular — will work in conjunction with 5G. LTE-A is available now on a number of devices, supported by such carriers as AT&T, Sprint, T-Mobile, and Verizon. LTE-A Pro is an evolution from LTE-A and began to make gigabit mobile broadband a reality. Gigabit LTE is comparable to the speeds of 5G services from early 2019 and is able to serve as somewhat of a stopgap until 5G matures. Gigabit LTE shares with 5G multiple input, multiple output (MIMO) antenna, and small cell technology.
Source: Android Authority
On the Way to the 5G Network, LTE Reigns
LTE lays the foundation for 5G networks, which are expected to deliver speeds of up to 20 Gb/s in ideal conditions and 100 Mb/s as a minimum. The increasing speeds associated with evolving 4G LTE variants will give consumers valuable experience with very-high-throughput applications before the 5G network becomes widespread.The Internet of Things (IoT) market began years before 5G was available thanks to LTE. In fact, the IoT installation base was already at 15.41 billion devices in 2015.
The details on the different LTE variants are mostly about improving what already exists and using what is available with LTE infrastructure, however they are examples of test cases that 5G took advantage of.
- LTE-A. LTE-A uses carrier aggregation to achieve higher speeds. By using multiple LTE bands at the same time, an LTE-A device experiences greater bandwidth, enhanced capacity, and increased speed. LTE-A also includes ongoing improvements in interference, cell coverage, and system throughput. LTE-A also introduced the use of low-complexity user equipment for IoT applications.
- LTE-A Pro. LTE-A Pro takes advantage of unlicensed spectrum and common Wi-Fi networks to increase speed even further. Carriers can use unlicensed spectrum either standalone or aggregated with licensed spectrum, thereby more effectively using cellular resources. A key capability of LTE-A Pro is reaching Gigabit LTE speeds, which finally leads the way for futuristic use cases such as augmented reality (AR)/virtual reality (VR).
- LTE-U. LTE-U refers to LTE technology that specifically takes advantage of unlicensed 5GHz frequencies.
The 5G-LTE Future
Advances in 4G LTE — in particular, LTE-A Pro — are allowing operators to continue upgrading their networks while they test the 5G waters. Through the incremental improvements that brought these advanced versions of LTE, like small cells, carrier aggregation, and IoT interoperability, network providers are paving the way for a smoother introduction of 5G.
Additional 5G LTE Resources
Updated March 2019