Why is Low Latency Important for 5G?

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- everything RF

Oct 14, 2020

Whenever we talk about 5G, the most discussed parameter is the insane upload and download speeds it can achieve. 5G services are being deployed around the globe with operators promising data transfer rates of hundreds of megabits per second. However, one very important improvement that is not very often discussed is in the latency department. Latency is the time taken for a signal to go from the source to destination and return to the source.

Efforts to improve latency were started with the introduction of 4G but it was never the main objective. However, this is not the case with 5G, where latency has been an integral part of the development of 5G technology. In an ideal situation, the time taken for a signal to be received by a base station transmitted from a mobile device on a 5G network should be 1-2 milliseconds! This is a major improvement from 4G LTE, which was already a significant improvement over the previous 3G technology. Verizon has reported that their 5G network achieves a latency of lower than 30 ms, which is an improvement of around 23 ms compared to the existing 4G network which takes over 53 ms.

Now, the question may arise in the minds of people is that if we are getting hundreds of MBPS or a few GBPS why do we need low latency? Low latency is important for a wide range of applications today. In many cases, this would hold more importance than a higher data rate.

Autonomous vehicles are a good example where latency is of utmost importance. Vehicles moving at high speeds require almost real-time information from their surroundings. During the development of 5G, self-driving vehicles were kept in consideration.

Similarly, Smart factories are another use case where low latency is a boon. Low latency means there is no longer a need to have wired connection for improved latency. The ability to go wireless not only removes a lot of hassle, but it also increases the mobility of robots which, in turn, can increase the utility and efficiency of said robots. Other industries where low latency is important are IoT, telemedicine and healthcare sector in general.IoT devices (Sensors) will send small amounts of data via 5G networks. In this case they do not need a high datarate but would rather to send and receive signals quicker.

Another use case of low latency is online gaming. Online gaming does not require high data transfer speeds, in fact the recommended internet connection for online gaming should have at least 3 Mbps download speed and 1 Mbps upload speed. Latency is of higher priority than the actual network speed in online gaming.

It is to be pointed out that latency and the frequency of signal are directly related. To achieve the very best latency, higher frequency bands or mm-Wave 5G can be used i.e the higher the frequency, the lower the latency. However, as we go higher in frequency, signal propagation and penetration become a challenge. This can significantly reduce signal power levels and thus impacts network coverage.

5G Frequency Bands vs Coverage vs Latency Comparison

Latency improvements in 5G is a massive advantage for applications that require real-time communication and mm-Wave 5G provides the best latency along with data rates never seen before in wireless communication. As the world has transformed digitally, the need for a better response time and instant feedback have become the new norm and 5G aims to deliver it.