What is 5G?
The word 5G is making a buzz over the last few years. And even in the last couple of years, many 5G smartphones are also launched. When we hear the word 5G, then the first thing which comes in our mind is high-speed internet. But 5G more than just high-speed internet.
5G is the fifth generation of mobile network technology. In many aspects, it is different from the previous generations of mobile network technology.
The figure below shows a quick comparison of how mobile wireless network technology has evolved over every generation.
Fig. Evolution of Mobile Network Technology with each generation
What 5G will offer to Consumers? (Key 5G Features)
There are three main technical goals of 5G:
- Enhanced Mobile Broadband (eMMB)
- Massive Machine to Machine Type Communication (mMTC)
- Ultra-Reliable and low latency communication (URLLC)
Figure: 5G vision (Key Features 5G will offer to consumers)
Enhanced Mobile Broadband:
Theoretically, 5G will offer a peak downlink speed of 20 Gbps and an uplink speed of 10 Gbps to users. When the signal is weak or at the edge of the cell, it will offer a speed of 100 Mbps. With this enhanced mobile broadband, users will be able to download the HD movies in a few seconds, or even in crowded places like airports and stadium, they will be able to enjoy HD streaming services. It will also accelerate the adoption of Augmented and Virtual Reality based services and cloud-based gaming (like google stadia).
Massive Machine to Machine Type Communication:
The massive machine to machine type communication enables the internet of things where millions of devices can be connected together without human intervention. And these devices can communicate with each other wirelessly. It will enable the gates for smart homes and smart cities. As per 5G specifications, it can support the connections of up to 1 million devices in the area of 1 km, which is 10 times more than the maximum supported capacity of 4G.
Ultra-Reliable Low Latency Communication:
This 5G feature will allow communication with latency as low as 1ms. It will enable real-time services that require ultra-low latency and prompt response like autonomous vehicles, remote surgeries, and interactive gaming. It is very helpful even in automation industries where fast machine to machine communication and ultra-reliable communication is very critical to avoid system failure and loss of life.
Overall, 5G will be superior in many technical aspects from 4G, be it mobility or energy consumption. Here is the Quick comparison between 5G and 4G.
Fig. Comparison between 5G and 4G
Fig. Comparison between 4G and 5G in tabular form
5G Spectrum (5G Frequency Bands)
5G will support two frequency ranges.
- FR1 – 410 MHz to 7125 MHz (sub 6 GHz band)
Initially, this first frequency range was limited to 6 GHz but now it is extended to 7GHz. But still, it is called a sub 6GHz band. This sub 6GHz band (FR-1) can be further divided into the low band and mid-band frequency.
In low band, as the frequency is less than 1 GHz, it provides a good coverage range and it can be used to provide coverage in the interior parts. The mid-band provides moderate coverage but because of increased bandwidth, the data speed will be better than previous generations. Currently, in many countries, this mid-band is used for 5G deployment.
2. FR2 – 24.25 GHz to 52.6 GHz (Beyond 6 GHz)
Strictly speaking, frequencies beyond 30 GHz are known as mm-Wave. But as this band also accommodates frequencies beyond 30 GHz, it is called a millimeter-wave band.
The true 5G experience and 5G speeds like 1 Gbps speed can be achieved with this mm-wave band. Because of high frequency, this band provides very high bandwidth and can provide blazing fast speed to the users. But this mm-wave can’t travel much distance and the coverage will be limited to a few tens of meters. They are known as small cells. To provide a really high-speed experience and to get the real potential of 5G, hundreds of such small towers of mm-Wave needs to be installed. At high frequency, as the antenna size also reduces and since 5G radios consume very low power, mm-wave radios can be installed even on the street lights.
The below figure shows the coverage range of different frequency bands.
Fig. Coverage Range of different frequency bands
What is Massive MIMO in 5G?
MIMO stands for multiple inputs- multiple outputs. In MIMO, both transmitter and receiver multiple antennas are installed. Multiple antennas improve the reliability and reduce the error rate in transmission and reception of data.
Fig. MIMO (Multiple Inputs- Multiple Outputs)
The MIMO is not a new concept and even in the previous generations like in 4G or even in WiFi technology also it is used. But in 5G, the scale at which this concept is used is massive.
Fig. Massive MIMO Phased Array Antenna Panel
The Massive MIMO system relies on three key technologies.
Spatial Diversity and Spatial Multiplexing
Special diversity means the same data can be sent over the different spatial paths. Using the same frequency and time slot. Which improves reliability and enhances the data rate.
The spatial multiplexing. Where different data is sent to the user over different spatial paths. Which increases the throughput to the end-user. It can be visualized as multiple pipelines that carry data between the base station and the mobile phone.
Fig. Spatial Multiplexing
By nature, this solution is very dynamic. With the continuous movement of the mobile user and changes in the surrounding environment, the mobile phone and the network require more advanced capabilities to continuously coordinate the link and manage the data transmission. But with 5G it is possible to achieve it.
In the multi-user MIMO technique, using the different spatial paths, different users can be served simultaneously on the same frequency in the cell. It will increase the cell capacity, which is the number of users, which can be served simultaneously. Serving multiple users with the same transmission increases capacity and allows for better utilization of resources. That adds up to the ability to download or stream with an improved experience for the user even in a crowded area.
Fig. Multi-user MIMO
Beamforming is another key wireless technique where a wireless signal is focused in a specific direction, rather than broadcasting to a wide area. To understand beamforming, you can think of the difference between a flashlight and laser pointer.
With the massive number of antenna elements in a massive MIMO system, beamforming becomes “3D Beamforming.” 3D Beamforming creates horizontal and vertical beams toward users. With 3D beamforming, it is possible to serve and track the user when they are moving on the street or moving between different floors in a building. Also having such narrow, direct beams reduces interference between other beams and increases the data speed.
Fig. 3D Beamforming
The massive MIMO will increase the cell capacity, which is total data volume that can be served to a user and the maximum number of users that can be served with a certain level of expected service. With the beamforming technique, it is possible to serve the moving users more reliably and overall user experience will improve.
What is Network Slicing in 5G?
Network slicing is a specific form of virtualization that allows multiple logical networks to run on top of a shared physical network infrastructure.
Fig. Network Slicing in 5G
As discussed earlier, the 5G network should provide Internet of Things (IoT), Mobile Broadband (MBB), and very low-latency applications simultaneously. All these different services required different Quality service and need different resources. For example, IoT connects a large number of devices. The throughput of each device will be low but to connect such a large number of devices, the network should be capable. On the other end, the users who want high-speed internet, their throughput will be high but no. of users will be low. Using network slicing, all similar types of services can be served using the same logical network. Network Slicing will increase service reliability and end-user experience.
Non-Standalone and Standalone 5G
There are two 5G deployment options. Non-standalone and standalone 5G.
In non-standalone 5G deployment, the core is still 4G core. But base station or the New Radio is 5G based. And it will be used only to provide fast data to the end-users. For the control and signaling still, the 4G architecture will be used.
Fig. Non-Standalone and Standalone 5G
Current 5G deployment focuses on eMMB to provide faster internet speed to the user. The advantage of non-standalone 5G is that the existing 4G infrastructure can be used for the 5G deployment. But the true potential of 5G can be experienced only in standalone 5G, where the core is also based on 5G architecture and NR is used on mm-wave frequencies. The network slicing and all low latency services can be provided to the user when the core is also 5G.
Gradually the mobile network operators will move towards the standalone 5G. But it will take some time. Even in the countries where 5G deployment is going on, it will take some time to experience true 5G features.
For more information, check this video on 5G.