5G networks are being deployed by two of the major local carriers. But one of the nuances of 5G is that it's really not a single network. It's a combination of different frequency spectra, with each one having a different use-case. I spoke with Telstra's Network Engineering Executive, Channa Seneviratne, about how different parts of the 5G spectrum will be used.
The main use cases for 5G can be separated into three categories; wireless back-haul over long distances, typical consumer cases for our smartphones and tablets, and short-range applications where there's a high density of connected devices in a relatively small area.
So, when we talk about 5G we aren't really talking about one network. Rather, it's a set of standards that cater for a variety of different use-cases that allows carriers to build a network of interconnected networks. And, unlike most of the previous wireless carrier networks, the focus is on data, rather than voice and text.
Covering long distances with low frequency 5G
Seneviratne said the 850Mhz frequency currently used by the 3G network will, over time, be repurposed so that people in remote areas can receive faster performance. And 5G can also transmit over longer distances so there's a dual benefit of better range and faster throughput.
The other benefit of 5G over the 850Mhz spectrum is that the signal can penetrate into buildings more effectively than 4G.
Another nuance to this is that the 900Mhz spectrum, formerly used by the now decommissioned 2G network, will be reauctioned and could be used for 5G as well, further bolstering the reach and speed of the new network. Telstra has a temporary license to access to that band for testing in its labs.
With other carriers looking at their own 5G ambitions - Optus has begun their 5G program and Vodafone might get there one day if the ACCC lets its proposed merger with TPG happen, we could see competition for this band resulting in a non-Telstra option in regional areas around the country.
The mid-band - covering most of the population
For most of us, the predominant frequency band we'll connect to using 5G will be the 3.4Ghz - 3.6GHz range. This is a higher frequency than 4G, which uses the 700Mhz to 2.4GHz band. It will be installed on those comms towers we see dotted around our towns and cities. When you see billboards and signs from Telstra about 5G, it's most likely that's the frequency band you'll be connecting to. It's already in eight major cities and a number of regional centres with network expansion planned for the next year expected to reach many more regional centres around the country.
One of the neat tricks that 5G can use is beam-forming. It's a technique many wireless routers use as well. In simple terms, the network can track a device and direct signal to that device directly instead of using a scattered beam and hoping it will reach the device.
Short waves and high frequencies for dense areas
Telstra is hoping to acquire a slice of the 26GHz, or millimetre wave, band for its 5G network. This band can only transmit relatively short distances, about 200 metres, but can handle lots of simultaneous connections. Carriers with access to this spectrum will be able to service places like stadiums and trains stations where there are lots of devices in a relatively small area. Hopefully, this means the days of having five bars of coverage but crappy service will be behind us.
We often hear that 5G will be the network that powers the Internet of Things (IoT). An application Seneviratne suggested was in a factory where there are lots of connected machines. Instead of running fibre or Cat 6 cables, 5G could provide the fast network required for wireless remote control of industrial machines and robots. Instead of creating your own network, Seneviratne suggested access to 5G for these applications could become a private leased network.