Fulfilling the potential of 5G means making the most of a limited resource: spectrum.
The radio spectrum is the part of the electromagnetic spectrum with frequencies below 300 GHz (spectrum designated for 5G tops out at around 100GHz).
The full range of spectrum designated for 5G includes < 1 GHz (low band), 1 – 6 GHz (mid) and > 24 GHz (high-frequency or millimeter wave).
But different frequencies have different communications properties. So how any 5G network chooses and uses its available frequencies/wavelengths will shape the capabilities and services it can offer.
The difference between high and low frequencies
Longer (low frequency) wavelengths travel longer distances – but support slower data speeds.
Shorter (high frequency) wavelengths travel shorter distances – but the data speeds can be much faster. Here are some examples:
Naval submarine comms – 30Hz – low, slow and looooong distances.
Wi-Fi – 2.4-5.8GHz – fast, but over relatively shorter distances
Millimeter wave – 24-100 GHz – extremely high speed, but limited distance
Not all 5G is the same
Because of the different properties of different frequencies, a 5G network with a lot of mid-range spectrum will have more flexibility to handle different environments and support different use cases.
A greater amount of spectrum also means more capacity: the ability to handle far more traffic. As demands for bandwidth skyrocket, that matters.
As a business customer, ask about every operator’s spectrum assets to see how well they meet your specific needs.
Case in point
While today’s urban CCTV systems tend to use low-resolution cameras, the 5G future will support advanced HD cameras.
For an HD camera mounted on a pole, millimeter wave spectrum (24 GHz and above) will deliver the necessary speeds, but the signal wouldn’t travel as far.
If you want to put that HD camera on a drone, you need mobility as well as speed. For that, you’ll want frequencies around the mid-band range – for high speeds and longer distances. Now you can monitor a vast area (think massive urban gatherings, train depots … think 5G).
So the spectrum your operator uses will also influence their ability to expand coverage of 5G. If you’re using mid-range frequencies that get high data speeds and long distances, you can cover more ground with fewer cell sites.
But if you’re only using the millimeter wave spectrum, you’ll need to set up a lot more towers to cover the same ground.
Antennae for a new network architecture
Another advantage of higher frequencies is that they need far smaller antennae sizes.
Transmitting on lower frequencies (like 600 Mhz) requires huge antenna elements. But when you use frequencies in the mid-band and above, you can use substantially smaller antenna elements.
The reduced antenna element sizes at higher frequencies allow integrating radio units with the antenna, which provides the capability for a significantly higher number of data streams. This is massive MIMO.
Massive MIMO is short for massive multiple input multiple output. It means you can have multiple independent data streams on each cell site instead of just a few. It’s like turning one cell tower into many.
Smaller antennae also mean getting more cell sites into smaller spaces (including indoors).
More antennae in smaller spaces across more sites. The new 5G network architectures will use far more, but smaller, cells in increasingly dense configurations.
Businesses will benefit from:
Faster speeds – for all applications and devices
More capacity – to support more demanding applications
Lower latency – with users closer to the network
More agility – to configure network solutions for specific needs
The bottom line: spectrum matters.
Talk to your potential operator vendors about their spectrum holdings and how they plan to deploy them for 5G.