The LTE technology used in many of our smartphones for voice/video calls or video streaming is 4G. In an era where 4G LTE is already an integral necessity in our lives, what is 5G? How will it change our lives? What can we expect from it?
Since the days of analog technology in the late 1970s, the mobile communication has been continuously evolving with each new generation enabling new services. In the early 2010s, when 4G LTE technologies were just hot off the press and commercial 4G services were about to take off, many organizations in academia and industry initiated research on next-generation breakthrough technologies with Samsung Electronics leading the pack with its own 5G research initiative in 2011.
In line with such research movement across the globe, ITU (International Telecommunication Union) held a World Radio Communication Assembly in October 2015 where they designated the official name of 5G as ‘International Mobile Telecommunication (IMT)-2020’ and published the technical vision of 5G. 5G mobile communication has three key components: (1) enhanced Mobile Broadband (eMBB); (2) Ultra Reliable & Low Latency Communications (URLLC); and (3) Massive Machine-Type Communications (mMTC).
According to ITU’s definition, eMBB can be characterized by a peak download speed of 20 Gbps and a user-experienced download speed of at least 100 Mbps. For example, downloading a single 15 GB movie takes at least four minutes for 4G LTE (at the peak data rate of 500 Mbps), but only six seconds for 5G at the peak data rate of 20 Gbps. Some of the new applications that are expected to be serviced over 5G are HD videos, virtual reality (VR), and augmented reality (AR).
For support of URLLC, 5G is able to provide 99.999% reliability and 1 ms latency (1 ms is 1/1000th of a second). For example, in a 4G network, when an obstacle appears in front of a self-driving car moving at 100 km/h, a stop signal can be received only after the car has driven more than 1 m. The same distance can be reduced to 2.8 cm in a 5G network, drastically reducing the risk of vehicular accidents.
Besides the big jump in data rates and latency, 5G is expected to play a critical role as a platform for providing connectivity to various forms of IoT devices in homes and industries. 5G aims to enable connections for 1 million devices within an area of 1km2. Such connectivity on a massive scale, i.e., mMTC, is essential in order to accommodate an exponentially increasing number of IoT devices such as smart devices and sensors.
To accommodate the requirements as described above, a new spectrum range was assigned for 5G, which is broader and higher than 4G. The spectrum range includes not only low frequency bands below 6GHz (including 3.5 GHz), which are similar to the conventional 4G spectrum, but also the ultra-high frequency millimeter wave (mmWave) bands such as 28 GHz and 39 GHz which were never previously used for the purpose of mobile communications.