5G and its foundation

Abhishek KC

Front-End Developer

People want faster data speeds and more reliable service. The next generation of wireless networks—5G—promises to deliver that, and much more. A task that could take 5-10 minutes on 4G LTE can be accomplished under a second using 5G. Wireless engineers say, this will boost the development of other technologies (Internet of things, Autonomous vehicles , Virtual reality, etc). It is said that the peak download speeds will be  20 gigabits per second (compared to 1 Gb/s on 4G) to users.

There are five new technologies that are emerging to make the foundation of 5G.

1. Millimeter waves:      

Due to increasing number of wireless network users, everyone is receiving less  bandwidth as the radio-frequency spectrum that mobile providers are receiving is still the same (i.e. under 6 GHz) . This means slower service and more dropped connections.Now the solution is to open up the new real estate. Millimeter waves are broadcast at frequencies between 30 and 300 gigahertz, compared to the bands below 6 GHz that were used for mobile devices in the past. They are called millimeter waves because they vary in length from 1 to 10 mm, compared to the radio waves that serve today’s smartphones, which measure tens of centimeters in length. Opening it up means more bandwidth for everyone. But there is a major drawback in millimeter wave. They can’t easily travel through buildings or obstacles and they can be absorbed by foliage and rain. That’s why 5G networks will likely augment traditional cellular towers with another new technology, called small cells.

2. Small cells:

Small cells are portable miniature base stations that require minimal power to operate and can be placed every 250 meters or so throughout cities. To prevent signals from being dropped, carriers could install thousands of these stations in a city to form a dense network that acts like a relay team, receiving signals from other base stations and sending data to users at any location.

5G base stations will also have many more antennas than the base stations of today’s cellular networks—to take advantage of another new technology: massive MIMO.

3. Massive MIMO

Today’s 4G base stations have a dozen ports for antennas that handle all cellular traffic. But 5G base stations can support about a hundred ports, which means many more antennas can fit on a single array. That capability means a base station could send and receive signals from many more users at once, increasing the capacity of mobile networks by a factor of 22 or greater.

MIMO is already found on some 4G devices.But massive MIMO has only been tested in labs.

Installing so many more antennas to handle cellular traffic also causes more interference if those signals cross. That’s why 5G stations must incorporate beamforming.

4. Beamforming

Beamforming is a traffic-signaling system for cellular base stations that identifies the most efficient data-delivery route to a particular user. This system receives all of the signals and keeps track of the timing and direction of arrival. It then uses signal processing algorithm to triangulate exactly where each signal is coming from and plots the best transmission route back through the air back to device.

5. Full duplex

Today's base stations and cell phones rely on transceivers that must take turns if transmitting and receiving information over the same frequency, or operate on different frequencies if a user wishes to transmit and receive information at the same time.

With 5G, a transceiver will be able to transmit and receive data at the same time, on the same frequency. This technology is known as full duplex, and it could double the capacity of wireless networks at their most fundamental physical layer.