Is 5G the reason to upgrade to that new phone?

In his book "Here I am", Johnathan Safran Foer has a quote, The older one gets the harder it is to account for time. While children might ask: "Are we there yet?" Adults might instead say "How did we get here so quickly?"

This is how I feel about 5G (Fifth-generation wireless technology) today. We are being inundated with information about 5G from phone manufacturers, wireless service providers, as well as economists. Reading some headlines, it even appears to be a matter of national security!

Having spent part of my career immersed in the wireless space, in this note, I plan to peel back the cover a little and explain some of the numbers that make up what 5G is all about from a layman's perspective.

A little historical perspective

I must admit, I am not working in the wireless space currently. But I know a little bit about it from having worked in this field for about 10 years. My natural curiosity, a healthy skeptical streak, and my training to dig for data drove me to try to understand the meaning behind the headlines and that is what I am sharing here.

As I was researching the evolution of Wireless Technology to take a historical look back at how we got here, I really liked a graphic that Micron used in an insight article they did in conjunction with data from Wikipedia. I have recaptured the graphic below to show the timeline of the different wireless technology generations. Here you can see that a generation of wireless technology seems to last between twelve (for 3G) and about twenty years (2G). Along the way, several wireless protocol enhancements bridged these generations (like GPRS/EDGE was labeled 2.5G) while LTE-A (or Long Term Evolution-Advanced) is bridging 4G and 5G. As the timing for the introduction, adoption, and deployment of these different wireless technologies vary across the world, it really is quite hard to clearly demarcate boundaries when one technology actually started or ended, but it helps to get a general sense of these timelines. Let's just say that a generation on average lasts about 15 years.

Figure 1

In the picture, I have annotated what technology highlight was enabled for a consumer in each of the different technologies. These technology highlights are meant to be representative rather than comprehensive for what each of these generations brought to the consumer. The first generation wireless technology (1G) provided the ability to make voice calls while being mobile. The second-generation (2G) added the capability to add short messaging services (SMS or text messages as we call them today) from the same end terminal device/phone, merging what used to be a secondary device called a pager (remember those?) which was used exclusively for text messages. 3G added the capabilities to send both data and voice on the same network, and introduced, the ability to browse the Internet (broad-band data) on your phone; 4G made this (internet browsing) ubiquitous and with increased data bandwidth (which we will cover further in the next section) made that a very seamless experience. There is one school of thought that says that while 5G is introducing a bunch of new technologies, it might be 6G before these technologies might be more seamless (just like going from 3G->4G was)

So what does 5G bring to the table?

5G brings many things but let's start with the growth of data

In Figure 2 below, I layer onto the previous graphic the data bandwidth that each technology supported. The best way to think about bandwidth is the amount of data that can be transferred (downloaded from say a website to your smartphone, tablet, or laptop) in one second. So, if 1G could support up to 2 kilobits/second, 5G can support up to 20 gigabits/second at its peak!

Figure 2.

If you are not living and breathing these numbers every day, it might be helpful to get an understanding of the scale at which these technologies are improving. In Figure 3 and Figure 4 below, I have plotted the data bandwidth for each successive wireless generation on a graph; While Figure 3 shows a gradual rise of the data bandwidth (Y-axis) with each successive technology (X-Axis), as one would expect, it is relevant to note that the Y-Axis is actually plotted on a logarithmic scale. On a purely linear scale, as shown in Figure 4, the same data shows how much the data bandwidth has improved just from 4G to 5G, and looking closely you can see how much (or how little) the data bandwidth for 1G->3G registers in figure 4.

Figure 3 Figure 4

And this is only one of the axes on which we are measuring the growth of 5G over 4G! So what are the other axes?

A more wholistic growth chart from 4G to 5G

If you study the International Telecommunication Union's specifications, here is the spider chart that compares IMT-2020 (commonly called 5G) with IMT-Advanced (commonly called 4G and represented with the lighter blues in the chart), reproduced below as Figure 5.

Figure 5

In this figure, there are eight axes on which 5G improves over 4G. The one we were discussing earlier in this note (what we called data bandwidth) is labeled as Peak data rate (Gbit/s) and appears about 11 o'clock in Figure 5. In six of the eight axes, the specification calls to improve the state of the art by at least one order of magnitude! One where the specification calls to improve by less than an order of magnitude, device mobility, - meaning the speed at which you can be traveling while using your phone - goes from 350 km/hr to 500 km/hr! On two of the axes (namely Area Traffic capacity - meaning the number of simultaneous user devices that can be present in a square meter - and Network energy efficiency - meaning the power consumed to handle the radio communications), the specifications call to improve the state of the art by two orders of magnitude!

This is mind-boggling! From a design/engineering perspective, pushing the envelope to accomplish one order of magnitude improvement on any one axis is hard enough, doing it along multiple axes is a significant challenge. While it has been 8 years since the specifications were started, a lot of these design features might take another 10 years to develop and deploy.

So Where is 5G targeted?

Taking a step back, what is important to understand here is that while most of the previous wireless technology evolutions (meaning 1G->4G) were directly targeted at "us" - the wireless device users -, 5G is broadening its target audience by adding a completely new set of "customers", including a lot more enterprise customers. These new 5G technologies will enable new business models, new revenue opportunities, for existing and new companies. For sure, the traditional phone consumer will get their share of the technology advances (and this is where the network carriers are targeting their initial advertisements to be able to generate revenue in the short term); But rest assured new companies will spring up that will offer features, services we can't even imagine today. I have written about these application spaces in another note.

Even for the phone consumer, to really be able to fulfill the promise of 5G, we still need infrastructure to be built out, spectrums to be bought, new radios to be designed, new antennas to be deployed, etc. For example, Mitsubishi back in November 2018 demonstrated the peak data download of 20Gbps over 10-100 meters, using 16-beam spatial multiplexing technology on antennae and the use of 24-100 GHz spectrum! These 20 Gbps downloads are possible because of the new 24+GHz spectrum and the multi-spatial antennae. However, 5G is not transmitted exclusively over this spectrum. It can, and will be, transmitted over the traditional low band (< 1GHz) and mid-band (1->5GHz) spectrums, though your download speeds will not be as high as those in the 24->100 GHz range.

Tom's Guide did a study recently (October 2020) and produced the following table that showed how the different carriers download speeds in 5G compared with 4G.

Figure 6

I guess that AT&T, Sprint/T-Mobile are using the mid-band spectrum, while Verizon is using the high-band spectrum in the limited cities where these tests were conducted.

Here are a few more comprehensive articles by ZDNET, PCMAG, and TomsGuide. that discuss the topic of getting a 5G phone today, some which describe why you should, and some which say why you should not! This 3-minute video produced by PC MAG seems to cover the basics very well (If you prefer seeing Videos over reading articles)

Conclusion

In conclusion, I would say that 5G eventually will provide advances for your phone, but in the short term (2-5 years), those advances will seem relatively pedestrian. The real action for 5G will actually be in some of the other application spaces. If you would like to read more about these applications spaces, read my article on What Can 5G do for me?.