5G is heralded as the major prerequisite enabler for the ‘Internet of Things’ (IoT) revolution and the panacea for poor mobile reception, long webpage load times and even worse, online videos that take an age to buffer... or so we might be led to believe from the latest 5G enabled smartphone adverts.
With 5G enabled smartphones just reaching e-commerce shelves, we might be nearing the peak of the 5G hype cycle. So, with a tonic of scepticism, we endeavour to avoid the current 5G related fake news (which includes theories that 5G spreads Coronavirus…) and instead attempt to review the data transfer realities under the 5G decade.
It is best to begin by appreciating that 5G represents a technology standard: an umbrella term from which a range of new and existing technologies will be brought together to improve data transfer. Yet, similar to the 4G roll-out, 5G will be rolled out gradually over time with new technology releases occurring throughout the 2020s. So, in summary, 5G should be viewed as an evolution of wireless communication and not a sudden step-change.
Looking back at history may provide us with a rough guide of what to expect from 5G. It was 1G that brought us voice communication. 2G enabled text message data to be transmitted. 3G ushered in the smartphone era and the web became mobile. 4G enabled faster web browsing allowing mobile devices to largely replicate the desktop PC. So, if history is any guide to the future we may expect 5G to increase data transfer speeds and unlock more data intensive processes.
Before assessing whether history gives us enough of a glimpse of our 5G future, it is worthwhile providing some context around the pros and cons of 5G by looking at a simplified explanation of how cellular networks work.
Mobile networks are split into geographically defined areas known as cells. Within each cell there is a tower which transmits and receives data from our mobiles and provides us with our network coverage. Data is sent over the cell using radio waves but, to reduce interference between cells, adjacent cells use slightly different frequencies. As mobile users move between cells the mobile network software seamlessly switches our mobile connection from one cell’s tower to another cell’s tower providing us with continuous mobile network coverage. With radio frequency affecting how much and how far data can be transmitted, and with radio waves affected by topography, building structures and population density, cell sizes have to vary.
A good way to visualise the bandwidth differential from 4G to 5G is to imagine the water throughput of a garden hose (4G) vs. a fire hose (5G)
Today, a growing problem on 4G networks is congestion. You’ve probably experienced this if you’ve tried, unsuccessfully, to watch a YouTube video at London Bridge station despite apparently having 4G mobile reception. This is caused by too many mobile users attempting similar activities across a narrow radio frequency band such that everyone’s bandwidth is thinned and the overall experience is poor. 5G seeks to use a larger bandwidth by incorporating millimetre wave technology; a higher frequency band of radio frequencies. A good way to visualise the bandwidth differential from 4G to 5G is to imagine the water throughput of a garden hose (4G) vs. a fire hose (5G). So, the roll out of 5G should ease network congestion as the larger bandwidth allows more data bytes to be sent concurrently.
This will allow cells to support more data intensive applications like augmented reality in addition to a significantly higher number of mobile devices. However, the major drawback of higher frequency millimetre waves is their relative fragility. Their shorter wavelengths suffer greater distortion by everyday objects and, relative to 4G, can’t go around corners or through brick walls as well; and so these 5G cells will need to cover much smaller geographical areas. Hence don’t be too shocked if 5G takes longer to roll out, coverage is somewhat unequal and, rural 5G benefits lag those of urban centres.
To mitigate these drawbacks, 5G networks will need to leverage other developing technologies to increase reliability and speed. For example, massive MIMO (multiple in multiple out) technology adds many antennas to mobile devices and cell towers to enable multiple pieces of data to be sent down separate routes. Another, beamforming technology, helps concentrate the flow of data similar to how a laser pen focuses light onto a point. Therefore smaller millimetre wave 5G cells will need to be supplemented by larger 5G cells operating at lower frequencies with these different technology combinations.
Due to greater 5G cell density and increasing technological complexity, a key growth opportunity for telecom operators may come from greater virtualisation: switching physical hardware into digital software applications akin to how apps on our mobiles replaced hardware gadgets (e.g. calculators, watches, cameras). Networks could then be upgraded frequently by software updates rather than hardware updates and network infrastructure could be shared reducing the telecom industry’s required capital outlay.
Whilst 5G seems more evolutionary for consumers, where it may prove revolutionary is in unlocking the potential of future IoT applications where latency matters. Latency represents the time taken between a decision and subsequent action being made. In mobile gaming, latency can severely hinder the user experience if there is a delay between your click and an in-game action so this industry looks set to benefit from 5G. Yet more importantly, investors should be thinking ahead to the myriad of other IoT enabled industries where precision, and therefore latency, matters crucially for success and could have life or death consequences (e.g. remote surgery).
Illustration by Adam Mallett