As most mobile phone users already use 3G and 4G networks, it is expected that 5G is likely to deliver new user experience in 2020, or even early in 2019.

What is 5G?
Although 5G is not expected to main market until 2020, several companies have already started investing to prepare ahead for the new wireless mobile standard, and trial 5G networks are already being set up in other corners of the world.

We explore 5G, how it works and its impact on future wireless systems.

5G stands for the fifth generation of the next wireless mobile standard.

According to the Next Generation Mobile Network's 5G white paper, 5G connections must be based on 'user experience, system performance, enhanced services, business models and management & operations'.

The 5G New Radio (NR) specification was released by standards body 3GPP in late 2017 - and chips are already being built '5G-ready'.

And according to the Groupe Speciale Mobile Association (GSMA) to qualify for a 5G a connection should meet most of these eight criteria:
1) One to 10Gbps connections to end points in the field
2) One millisecond end-to-end round trip delay 
3) 1000x bandwidth per unit area
4) 10 to 100x number of connected devices
5) (Perception of) 99.999 percent availability
6) (Perception of) 100 percent coverage
7) 90 percent reduction in network energy usage
8) Up to ten-year battery life for low power, machine-type devices

Previous generations like 3G were a breakthrough in communications. 3G receives a signal from the nearest phone tower and is used for phone calls, messaging and data.

4G works the same as 3G but with a faster internet connection and a lower latency (the time between cause and effect).

4G is supposed to be at least five times faster than existing 3G services and theoretically, it can provide download speeds of up to 100Mbps.

Hubert Da Costa, vice president, EMEA at 5G routers business Cradlepoint said: "5G Wi-Fi connections are set to be about three times faster than 4G, starting with 450Mbps in single-stream, 900 Mbps (dual- stream) and 1.3G bps (three-stream). So, whilst we are already starting to see a huge growth in IoT and smart devices, 5G's speed and capacity will enable an even more rapid arrival of this connected future."

Advantages of 5G
Like all the previous generations, 5G will be significantly faster than its predecessor 4G. 

This should allow for higher productivity across all capable devices with a theoretical download speed of 10,000 Mbps.

"Current 4G mobile standards have the potential to provide 100s of Mbps. 5G offers to take that into multi-gigabits per second, giving rise to the ‘Gigabit Smartphone’ and hopefully a slew of innovative services and applications that truly need the type of connectivity that only 5G can offer," says Paul Gainham, senior director, SP Marketing EMEA at Juniper Networks.

Plus, with greater bandwidth comes faster download speeds and the ability to run more complex mobile internet apps.

Disadvantages of 5G
However, 5G will cost more to implement and while the newest mobile phones will probably have it integrated, other handsets could be deemed out of date.

A reliable, wireless internet connection can depend on the number of devices connected to one channel. With the addition of 5G to the wireless spectrum, this could put us at risk of overcrowding the frequency range.

The problems with 4G and even 3G aren't exactly filling us with the hope of an immediate super fast connection.

For a long time (and still even now) certain handsets and areas of the world don't support or can access 4G connections, so the rollout for 5G is likely to be very patchy.