Aargh! Yet another G? And, just after we have just come to terms with LTE! So, what is this 5G? What is so special about it? First, let us take a lookback at the timeline of cellular network technology. 0G was the era of the analog radiotelephone. 1G introduced the world to mobile phones. 2G kick-started mobile revolution and allowed users to digitally text one another. 3G transported mobile phone users online for the first time. 4G supplied faster speeds that you and I enjoy today.
Now as the world witnesses an explosion in the sheer number of empowered IoT users, be it in the form of smartphones, tablets, smartwatches and other wearables, toys, cameras, smart TVs or smart speakers, 4G networks seem to have reached its optimal threshold of functioning. Users want even more data for their smartphones and other Internet of Things (IoT) devices.
That is exactly why we are moving towards 5G, the next generation of wireless. It is expected to handle about a thousand times more traffic than existing networks and probably around 10 times faster than 4G LTE. In this article, let us discuss 5 G’s you need to know about the next big thing in mobile technology.
I don’t really think I have to elaborate on this one. 5G is pillared on the premise that the IoT i.e. connected devices be it self-driving cars or smart homes will become insanely relevant in the not so distant future. Mobile data networks will need to be extremely robust to handle it all. With wearables, appliances, automobiles, mobile AR and VR devices etc. expected to put so much traffic through mobile data networks, with certain devices requiring as many as multiple GB/second, there will be a demand not merely on speed but also on reduced latency. 5G strives to mitigate latency issues to as low as one millisecond in order to facilitate real-time functioning of vital devices. More importantly, it boasts of a speculative maximum speed of 20 GB/second, which is significantly faster than the quickest 4G LTE networks today. Impressive, right? Imagine how your life would change when you can download Jurassic World: Fallen Kingdom in a few seconds instead of a few minutes! Of course, we are talking of the upper caps, and the average speed for typical users will hover around 100 Mbps. This is still faster than the actual performance of several LTE deployments. Part of this awesomeness is due to the use of higher frequency waves, which enhances the capacity for beamforming (we shall talk about this shortly). Essentially, 5G is all about super quick response times, which is crucial for IoT devices.
From the inception of mobile networks, smartphones and other electronic devices use very specific frequencies on the Radio Frequency (RF) spectrum, typically between 3 KHz to 6 KHz. This was cool when devices were largely confined to cellular phones. However, with an upsurge in the number of IoT devices requiring uninterrupted express connections, these frequency bands are becoming increasingly overcrowded. Mobile networks can only squash in so many bits of data on the same amount of RF spectrum. It is thus, obvious that no device would secure an apt amount of bandwidth to operate as designed, terminating in sluggish speeds and dropped connections.
5G also requires a technology called Full Duplex. Today’s cellular base stations can do only one job at a time: either transmit or receive. If one data stream is transmitted on one path, while another data stream is coming from the opposite end using the same path, it will result in serious interference. Researchers are using silicon transistors to build high-speed switches that kind of acts as a signalling system that can transitorily reroute the data streams such that they can get past each other. This implies that there is more data efficiency on each frequency.
The pace of growth of IoT connected devices is pegged to skyrocket in the next one or two years. It is predicted that by the end of 2020, the average consumer will own at least 6 to 8 connected devices, carrying three with them at all times. If all these devices were to crowd our lives, we need more real estate, and not just on land. Millimetre waves amplify the frequency spectrum from 6 GHz to 300 GHz, allowing for increased bandwidth and data for global masses. However, since this segment of the spectrum has never been used before for mobile devices, not all of the frequency spectrum shall be used all at once. In fact, the average consumer would initially be exposed to spectrums ranging from 24 to 40 GHz typically.
For 5G networks, we require multi-user massive MIMO (Multiple Input Multiple Output), which will be employed on cellular base stations. This is critical in order to establish connection for high-density devices in specific areas. At present, base stations have around a dozen ports to receive and transmit all the traffic. We spoke about millimetre waves, which ensures greater data for all. However, they are easily scattered and absorbed by the atmosphere, weather anomalies and even buildings, thus requiring line-of-sight communication. This is where the current 4G network often struggles. This is exactly why you have varying signal speeds at various locations at various points of time. Using small cell networks would help solve the problem. It uses thousands of low-power mini base stations, which are far denser than traditional towers, thereby forming kind of a relay team to transmit signals around obstacles. As you move around in a city, imagine that you move behind an obstacle, your smartphone will automatically switch to another base station in better range of your device. However, the probability of latency remains.
Massive MIMO inserts the ability to add hundreds of antennas per base station. This could augment the capacity of existing networks by a factor of 22 or more. With the IoT universe swelling up along with global population, massive MIMO deployment will be able to proffer enhanced connectivity to over 1 million devices every square kilometre. This is enough to provide quality connection in major hubs and major population concentrations in the city.
With a rise in the demand for autonomous driving cars, smart wearables, smart homes and what not, even traditionalists are estimating an exponential growth to around 50 billion IoT devices by end-2020 from the current 28.4 billion. For mission-critical services such as smart city infra, controlled automobiles, remote surgeries and healthcare, industrial processes, there will also be a shared spectrum ranging from 60 Ghz to 70 Ghz. These mission-critical services warrant ceaseless ultra-high speeds, coverage, mobility, reliability and security along with ultra-low latency, energy and cost.
This is where 5G makes its mark with a shared spectrum, ensuring that the devices are always connected. This shared spectrum is also designed, keeping in mind consumer usage patterns and behaviour. For instance, if a shared spectrum space is not accessed in one customer’s location, while there is a massive density of and demand for customer devices in another region, a portion of the spectrum space through a blank sub-frame can be allocated for temporary use. So next time you are talking on your phone and you wish to enter your voice-activated house, you do not have to disconnect the phone to open your voice-enabled lock. It is evident, how the groundwork for IoT universe needs to be laid down before introducing 5G in the market.
While we revelled in the plethora of benefits offered by massive MIMO, we also need to fathom its limitations. The cellular 4G masks that we have today, instantaneously broadcast information in all directions; these intersecting signals trigger serious interference, resulting in distorted or destroyed data. To overcome this glitch, we need something called 3D beamforming. Beamforming is like a traffic signalling mechanism for cellular signals. Instead of omnidirectional broadcasting, 3D beamforming would allow a base station to send a concentrated data stream to a definite user. This precision prevents interference and is evidently, far more efficient. Base stations can now handle increased incoming and outgoing streams of data simultaneously. Imagine you are in a cluster of skyscrapers and you are trying to make a phone call. Given existing 4G ports, your signal might rebound or overlap with signals from other users in the area. A massive MIMO base station accepts all these signals and keeps track of their timing and the trajectory of their influx. It then uses signal-processing algorithms to triangulate exactly where each signal is originating and then plots the best transmission trajectory to each phone. The upshot is a coherent data stream delivered only to you.
We’re not quite there yet! 5G is still a work in progress. Researchers are still attempting to bridge the gaps between millimetre waves, small cell networks, massive MIMO, beamforming and full duplex. Making these above systems work together is a different ball game altogether. They might come up with other new technologies too. 5G projects are still being trialled. For instance, a 5G experiment that took place few months ago in the Millennium Square at Bristol, aimed to give the public a peek into the 5G experience. They created a communal VR experience, which showed streaming of high bandwidth content on multiple devices simultaneously. This was all on one network, without any time lag or dropout. Interestingly, Verizon, Ericsson and Qualcomm have successfully completed their preliminary trials of massive MIMO with a fully compatible IoT device.
Industry pundits subscribe to the view that 5G might touchdown as early as late 2020 and become pervasive by around 2025. Even them, primitive 5G networks would come with their own baggage like erratic coverage or precipitously exhausting your battery life.
Shaunak is an Assistant Professor, Faculty of Management, St. Xavier's College (Autonomous), Kolkata. He is an experienced research scholar with a demonstrated history of working in the marketing and advertising industry. He holds a Master of Commerce in Marketing Management from St. Xavier's College.