LTE or Long Term Evolution is the most widely deployed and adopted cellular technology today. LTE represents the fourth generation of mobile networks, and LTE Advanced is one of the key enhancements added to LTE to improve the data rates considerably.
LTE or 4G LTE is the fourth generation of mobile networks that uses the Long Term Evolution technology to offer peak data rates of 300 Mbps; LTE Advanced is an enhancement added to LTE to improve peak data rates to 1 Gbps through carrier aggregation, 256 QAM and higher-order MIMO (8×8 DL & 4×4 UL).
| LTE (4G) | LTE Advanced (4G+) | |
|---|---|---|
| Supported bandwidths | 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz | 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz |
| Carrier aggregation | None | Ability to combine or aggregate up to five (5) frequency carriers |
| Quadrature Amplitude Modulation (QAM) | QPSK, 16 QAM, 64 QAM | 256 QAM |
| MIMO (Multiple Input Multiple Output) antenna configurations | MIMO 4×4 Downlink; 2×2 Uplink | MIMO 8×8 Downlink; 4×4 Uplink |
LTE or Long Term Evolution is the underlying cellular technology that enables the fourth generation of mobile networks or 4G. The first publicly available LTE mobile network was launched in the Scandinavian cities of Stockholm and Oslo in 2009. Even though we still have the second-generation (2G) GSM and third-generation (3G) UMTS networks, 4G LTE has become the primary technology that serves us for most of our cellular needs. As a result, we frequently see symbols like 4G, 4G+, LTE, and LTE+ popping up on our smartphones. The 4G and LTE symbols suggest that a mobile phone is being served by the LTE technology, while the 4G+ and LTE+ symbols mean that a mobile phone is connected to the LTE Advanced technology.
Difference between LTE and LTE Advanced
LTE is the cellular technology that 4G networks are based on, and LTE Advanced is an enhancement that improves the original LTE technology. LTE, as per 3GPP Release 8, provides peak data rates of up to 300 Gbps, whereas LTE Advanced, as per 3GPP Release 10, enables peak data rates of up to 1 Gbps.
LTE and LTE Advanced are cellular technologies that were introduced as part of the fourth generation of mobile communications. When LTE was originally launched in 2009, it already supported the technical capabilities that provided the framework for LTE to grow over time. This framework introduced network enhancements like LTE Advanced and LTE Advanced Pro to improve data rates significantly.
LTE is essentially the underlying cellular technology that LTE Advanced and LTE Advanced are built upon. The original launch of LTE followed the specifications set by the standards organisation 3GPP (Third Generation Partner Project) in 3GPP release 8. The work continued in the following release, Release 9, to lay a solid foundation for LTE networks.
The original LTE standard supported flexible bandwidths allowing mobile operators to use smaller or bigger frequency channels (also known as carriers). Bigger carriers have more capacity, which can enable higher data rates. LTE networks support bandwidths of 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz.
The first key difference between LTE and LTE Advanced is Carrier Aggregation, a technique that allows LTE Advanced networks to increase the total carrier bandwidth by combining multiple carriers (channels). LTE Advanced supports aggregation of up to five (5) carriers, allowing LTE Advanced to offer a maximum carrier bandwidth of 100 MHz by combining five 20 MHz carriers (5 x 20 MHz = 100 MHz).
The second difference between LTE and LTE Advanced is the use of a higher number of antenna elements in LTE Advanced. Both LTE and LTE Advanced employ the MIMO technology (Multiple Input Multiple Output) for spatial multiplexing to improve data rates and signal quality.
LTE Advanced networks use 8 x 8 MIMO in the downlink compared to 4 x 4 in the original LTE. It means LTE Advanced networks can have eight (8) communication layers from the base station to the mobile phone (downlink). In the uplink direction, from phone to base station, LTE Advanced networks employ a MIMO configuration of 4 x 4, which is higher than the 2 x 2 used by original LTE.
Finally, the original LTE technology employs Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation (QAM) and 64 QAM. LTE Advanced uses 256 QAM, a higher-order modulation than the original LTE, to generate a lot higher bit rates per symbol. LTE Advanced Pro uses the same modulation order.
| Carrier Aggregation | MIMO antenna technology | QAM Modulation | |
|---|---|---|---|
| LTE | None | 4 x 4 in Downlink and 2 x 2 in Uplink | QPSK, 16 QAM, 64 QAM |
| LTE Advanced | Up to five (5) carriers | 8 x 8 in Downlink and 4 x 4 in Uplink | 256 QAM |
| LTE Advanced Pro | Up to thirty-two (32) carriers | 8 x 8 in Downlink and 4 x 4 in Uplink | 256 QAM |
How much faster is LTE Advanced compared to LTE?
LTE Advanced can offer a lot higher download and upload speeds than the original LTE technology. As per the specifications from 3GPP Release 8, the original LTE networks can offer maximum download speeds of up to 300 Mbps. The average download speed of LTE is around 15-20 Mbps, as shown in the picture below.
LTE-Advanced and LTE-Advanced Pro networks can take these speeds to another level due to the enhancements like carrier aggregation and superior MIMO and QAM configurations. LTE Advanced networks can offer maximum download speeds of up to 1 Gbps. LTE-Advanced later saw another enhancement in the form of LTE-Advanced Pro, which can offer peak download speeds of up to 3 Gbps.
The average download speed of LTE Advanced can vary a lot depending on whether it is LTE Advanced or LTE Advanced Pro and how the different configurations of the LTE networks, e.g. carrier aggregation, MIMO and QAM, are used by your mobile operator. Mobile phones and other cellular devices are also categorised depending on which enhancements they support, which can also impact the achievable data rates. Based on a test we carried out in Reading, UK, LTE Advanced networks can offer average download speeds of between 60 to 80 Mbps, as shown in the picture below.
LTE Advanced is forward compatible, which means that any earlier LTE devices that existed before the LTE-Advanced launch would still be able to access the LTE-Advanced network, so a customer would not need to buy a new device to be able to access the LTE-Advanced frequencies. However, the post-LTE-Advanced devices may fall within a higher device category, allowing them to access a wider range of LTE-Advanced features than the earlier devices.
I have written a dedicated post on LTE and LTE Advanced average download and upload speeds, which can provide you with a comprehensive view of what average speeds to expect.
MIMO, QAM & CA: How can LTE-Advanced offer higher data rates?
LTE Advanced and LTE Advanced have superior features and configurations to the initial LTE networks. One key feature within LTE Advanced is Carrier Aggregation (CA), which takes advantage of the flexible bandwidth option in LTE and adds the capability to combine multiple carriers into one big overall carrier. With Carrier Aggregation, a user device, e.g. a mobile phone, can access a much bigger data pipe and therefore, the achievable data rates improve significantly.
Carrier aggregation is further supported by antenna technology enhancements to make the overall frequency spectrum usage more efficient. This is accomplished through improvements to MIMO (Multiple Input Multiple Output) antenna scheme. MIMO in LTE networks enables spatial multiplexing to transmit the overall data content through multiple parallel data streams. In LTE Advanced, transmission layers increase to eight (8) for downlink and four (4) for uplink.
Finally, a higher-order digital modulation technique allows LTE Advanced to deliver higher bits per symbol. LTE networks use Quadrature Amplitude Modulation (QAM), which is highly efficient for OFDM-based LTE networks. In LTE Advanced, the modulation order increases from 64 QAM to 256 QAM, improving spectral efficiency and the data rates.
Another benefit of LTE-Advanced networks over earlier networks is that they have capabilities that make it easier to deploy heterogeneous networks – HetNet, which improves network coverage and capacity for an end-user. With heterogeneous networks, a range of different kinds of cell sites such as the main cell site (macrocell), microcells, and picocells can work together to create the required network coverage and capacity. The key technical capability that makes it happen is the relaying technology in the form of relay nodes.
Relay nodes can lead to improvements in both coverage and capacity of a cellular network. They work similarly to small cells and repeaters, but there are advantages to using relay nodes. Relay nodes are better than repeaters from a coverage viewpoint because repeaters amplify everything in the signal, i.e. the actual information content plus noise.
Relay nodes are small base stations, not that different from small cells, but they have the ability to utilise the existing mobile base station for backhaul purposes. Instead of using dedicated fibre or other solutions, relay nodes can work with the main 4G cells (eNodeB) to serve the end-users. It does not change anything for customers because the mobile phone sees a relay node as just another cellular tower.
How to know if your phone supports LTE Advanced?
LTE Advanced can offer much higher data rates for uploads and downloads if you are looking for higher data speeds on your mobile phone. It also helps when you are trying to use your phone as a hotspot. If you want to perform basic web browsing tasks on your phone, make a phone call or send text messages, then both LTE and LTE Advanced can provide sufficient bit rates for your needs.
The easiest way to find out whether your phone supports LTE Advanced is to check the top of your mobile phone screen. If you see a symbol showing 4G+ or LTE+, then your phone supports LTE Advanced. It is also a good way of knowing which technology is supporting you at any given time. For example, in the screenshot below, the phone is served by LTE Advanced, which means the phone user can expect higher data rates.
However, this option is not available on all mobile phones. For example, on iPhones and Google Pixel, you usually only see the network generation, e.g. 4G or 5G. For those phones, you can either look at the phone specifications on the manufacturer’s website or check out GSMArena and enter your phone model to find out if it supports LTE-Advanced. The other way is to go to an app store and search for “cellular tower” to find apps that show you which cellular tower is serving you. Those apps show you which mobile network cell is serving you, and if LTE Advanced serves you, you can expect to see LTE-A or CA (Carrier Aggregation).
Conclusion
LTE is the cellular technology that enables the fourth generation of mobile networks that are referred to as 4G networks. LTE has seen a number of enhancements, including LTE Advanced and LTE Advanced Pro. LTE-Advanced is an enhancement added to the LTE networks to introduce features that improve the overall spectrum efficiency to deliver higher data rates. LTE-Advanced can offer peak data rates of up to 1 Gbps and average data rates of around 60-80 Mbps. LTE can offer peak data rates of up to 300 Mbps and average download speeds of around 15-20 Mbps. The key enhancements that differentiate LTE Advanced from LTE are:
Carrier Aggregation
Carrier Aggregation combines multiple carriers into one to create a bigger overall carrier that can deliver higher data rates. LTE Advanced allows carrier aggregation of up to five (5) carriers.
MIMO antenna technology
MIMO enhancements: LTE Advanced networks use a higher-order MIMO configuration which allows a higher number of antenna elements for the transmission and reception of mobile signals. LTE Advanced uses a MIMO configuration of 8 x 8 in the downlink and 4 x 4 in the uplink.
QAM Modulation
Higher-order QAM modulation: LTE Advanced and LTE Advanced Pro networks employ 256 QAM, which is considerably higher than the QAM configuration LTE networks use.
Here are some helpful downloads
Thank you for reading this post. I hope it helped you in developing a better understanding of cellular networks. Sometimes, we need extra support, especially when preparing for a new job, studying a new topic, or buying a new phone. Whatever you are trying to do, here are some downloads that can help you:
Students & fresh graduates: If you are just starting, the complexity of the cellular industry can be a bit overwhelming. But don’t worry, I have created this FREE ebook so you can familiarise yourself with the basics like 3G, 4G etc. As a next step, check out the latest edition of the same ebook with more details on 4G & 5G networks with diagrams. You can then read Mobile Networks Made Easy, which explains the network nodes, e.g., BTS, MSC, GGSN etc.
Professionals: If you are an experienced professional but new to mobile communications, it may seem hard to compete with someone who has a decade of experience in the cellular industry. But not everyone who works in this industry is always up to date on the bigger picture and the challenges considering how quickly the industry evolves. The bigger picture comes from experience, which is why I’ve carefully put together a few slides to get you started in no time. So if you work in sales, marketing, product, project or any other area of business where you need a high-level view, Introduction to Mobile Communications can give you a quick start. Also, here are some templates to help you prepare your own slides on the product overview and product roadmap.
