Connectivity for IoT projects can be achieved in several ways – Ethernet, Wi-Fi and ZigBee are just some of them, but one of the most powerful and adaptable methods is to use existing cellular networks provided by Mobile Network Operators (MNOs). Using 4G for IoT is one of the leading options.

Although 5G is grabbing all the headlines right now, its predecessor, 4G, is still a highly capable technology and in many ways is ideal for offering IoT connectivity for many types of use cases.

In fact, data from ABI Research shows that 4G continues to dominate in the IoT connectivity space, with more than 60% of IoT modules using the technology.

What is 4G?

4G is the fourth generation of mobile phone technology, the successor to 2G and 3G. With 5G continuing its roll out in markets across the world, 4G is essentially the current mainstream generation.

The first generation, or 2G, was an analogue technology that allowed people to talk on the move.

2G enabled people to make calls and send texts, including data services like MMS and SMS.

3G introduced the ability to use more demanding data services and applications like accessing the Internet and video calling.

4G can support a much greater number of users than 3G. Using high speed upload and download data packages, 4G offers mobile access to broadband speeds from a smartphone or laptop. Generally, 4G is about three times as fast as 3G.

As well as speed, dependability is one of the great benefits of 4G – in addition to allowing a greater throughput of traffic and so avoiding congestion, it is also much more reliable than 3G.

What is 4G LTE?

One of the commonly used terms in cellular network connectivity is 4G LTE. LTE stands for Long Term Evolution, a group of technologies most commonly used on 4G networks – while LTE is not strictly the same as 4G, LTE has evolved to work on 4G.

Essentially, LTE is a redesign of the 3G standard. This redesign incorporates a core network based on IP addresses, a simplified network architecture, a new radio interface and a new modulation method. It also allows for a technique known as MIMO (multiple input, multiple output), which uses several antennas to provide greatly increased data capacity.

When introduced in 2008, LTE launched a new cellular access network which provided higher data rates, better spectral efficiency and short round trip times. Known as latency, this is typically less than 100 ms.

4G LTE offers a typical download speed of 20Mbps, which theoretically could be raised to 150 Mbps.

The technology brings numerous advantages to any user of data services. One of the chief benefits is that is it very widely available all across the globe, both for consumers and for users of commercial and industrial applications.

Older 2G and 3G networks are now being retired, so LTE provides continuity for networks in the long term. It also acts a bridge between these older technologies and the newer 5G, which will not provide ubiquitous coverage for some time.

LTE Categories

LTE is divided into 20 different User Equipment categories, which are needed to ensure that the base station communicates properly with the user equipment.

What we might call ‘original’ LTE has categories 1 to 5, providing downlink data rates from 10 to just under 300 Mbit/s, while categories 6,7, and 8 are considered part of the newer LTE Advanced. Categories 6 and 7 provide a data rate just over 300 Mbit/s while 8 offers a nearly tenfold increase to 3000 Mbit/s.

LTE Advanced offers higher speed and improved stability compared to original LTE. These higher speeds are achieved by aggregating channels, allowing users to download data from a number of different sources simultaneously.

There is also LTE-M, also referred to as LTE CAT-M1, a much simpler version of LTE designed specifically to work with battery powered IoT devices. It allows these devices to send and receive data over cellular networks in a much more power-efficient way.

Example use cases

There are many use cases that can benefit from the high data rates, low latency, high reliability and widespread availability offered by LTE.

One of these is video surveillance to provide monitoring and security of facilities such as airports, transport hubs and public spaces such as concert halls and shopping malls. In this application, video cameras are connected to the internet, requiring the high data capacity of 4G LTE to send live images to a control centre. LTE connectivity is even more vital where the cameras are mobile, such as on police vehicles, drones or wearable body cams.

Other use cases demanding the low latency of LTE are applications involving automated guided vehicles (AGVs) in factories. Low latency is essential if these AGVs are to report their position accurately and instantly. Using an IoT connection, the robots can offload data to the Cloud, allowing analysis of the data and coordination of robots and AGVs.

4G LTE versus 5G

Beyond 4G, 5G is developing rapidly as the latest generation of mobile access network and offers even more potential for IoT applications. The main difference between 4G and 5G is speed. Theoretically, 5G can reach speeds that are 20 times faster than 4G LTE – while 4G has a peak speed of 1GB per second, 5G could achieve speeds of around 20GB per second in the best conditions.

This is because 5G can use much higher frequencies than 4G. Frequencies can range from below 6GHz up to 54GHz, with the higher ranges allowing many more simultaneous connections than 4G.

These frequencies affect the coverage that can be achieved. Lower frequencies can achieve long ranges, but the higher frequencies can be blocked by objects such as trees and buildings. This means that the positioning of IoT modules using 5G needs to be carefully considered, particularly if they require the high data rates offered by the higher frequencies.

5G will also offer even lower latency than 4G. It is expected to drop to around 10ms, with even 1ms theoretically attainable in ideal conditions.

Whatever IoT connectivity method you decide to use, Pelion offers a fully managed IoT solution to suit.