6G isn't widely available yet, but the latest specification -- Wi-Fi CERTIFIED 6 Release 2 -- was released in January 2022. For the average user, 6G is unlikely to replace 5G completely or immediately, it will build on existing 5G infrastructure. The cornerstone of 6G technology is that it will utilize higher frequency bands of the electromagnetic spectrum than 5G, enabling faster data transfer rates, reducing network congestion and lowering latency.

The use of 6G and spread spectrum to terahertz (THz) frequencies will more effectively support new technologies and applications ranging from wireless brain-computer (BCI) devices to the Internet of Things in Space (IoST).

What is spectrum in wireless networks?

Spectrum in a wireless network refers to the radio frequency (RF) range used by signals such as Wi-Fi. Spectrum is grouped into frequency bands, which define the high and low frequencies within each spectrum. Within each frequency band, a certain amount of Wi-Fi usage capacity is allocated.

KHz, MHz, and GHz are measurements of frequency (cycles of velocity per second). The frequency bands available in wireless communication are usually between 20 KHz and 300 GHz, and are usually divided into low, mid and high frequency bands.

The low, mid and high frequency bands have different characteristics. A recent Accenture study identified the following average ranges for these frequency bands:

Low-band spectrum (3.1 GHz to 3.45 GHz) enables data to travel greater distances while reducing signal interference.

High-band spectrum (7.125 GHz and 8.4 GHz) shortens the distance that data can be transmitted, but data can be transferred faster than low-band spectrum.

Mid-band spectrum (4.4 GHz to 4.94 GHz) provides capacity between low-band and high-band spectrum.

The often-used term sub-6GHz usually refers to the mid-low frequency bands below 6GHz.

governing body

In the United States, for example, frequency allocation is governed by the Federal Communications Commission (FCC). The full frequency allocation table can be viewed here.

Standards for the network generation are developed by various governing bodies, such as the 3rd Generation Partnership Project (3GPP) and its partners.

5G vs 6G Spectrum Comparison

Certification

While subsequent wireless technologies are often referred to as upgrades or new releases, they are new iterations of wireless technologies with different use cases. Each generation may release multiple versions. For example, the latest version of the 5G standard is 17.

The original 6G standard covered the 2.4 GHz and 5GHz frequency bands. The 6E standard (where "E" stands for extended) extends 6G capacity into the 6 GHz band, allowing up to 1,200 MHz of additional spectrum. For simplicity, Wi-Fi CERTIFIED 6 Release 2 covers all three frequency bands.

• 5G – Specified by the IEEE 802.11ac standard
• 6G – Specified by the IEEE 802.11ax standard

Typical equipment

• 5G - Smartphones, PCs and laptops, sensors and drones.
• 6G - Self-driving cars, cellular devices, Wi-Fi implants (small microchips that use NFC to communicate in the retail industry), and public infrastructure such as traffic and weather systems.

Example

5G was developed to support the ever-evolving Internet of Things (IoT). It is designed to support smart applications such as smart agriculture and smart cities, telemedicine, virtual reality, enhanced mobile broadband (eMBB), and sensory-based applications such as immersive gaming. However, the spectrum it uses has become increasingly crowded and cannot effectively support some emerging technologies.

6G is designed to accelerate IoT systems and will be widely used in business and industry to expand the capabilities of edge computing devices in military, holographic communications, remote driving, connected robotics and autonomous systems (CRAS) and wireless brain-computer (BCI) devices, and enhance the digital twin. 6G is expected to play a key role in IoSTs such as unmanned aerial vehicles (UAVs) and CubeSats (small satellites). It will be used in the personal domain for applications such as autonomous systems, haptic and sensing devices, and advanced extended reality (XR) applications. The vision of 6G is to support the Internet of Everything (IoE).

maximum frequency

A band includes a range of frequencies, sometimes expressed in wavelengths.

• 5G – 100 GHz
• 6G – 10 THz

maximum bandwidth

Bandwidth describes the size of the frequency band, the highest frequency available minus the lowest frequency. Because 6G will use higher frequency bands than 5G, it will be faster and provide higher throughput. Throughput in wireless networks is a measure of the actual data transmitted between network devices, while bandwidth refers to the theoretical capacity of the network to transmit data. This theoretical capacity is much higher than what users expect in reality. Signal interference, physical obstacles, and the distance between the device and the wireless access point (AP) can all negatively affect actual throughput.

• 5G – 1 GHz
• 6G – 100GHz

peak data rate

Data rate refers to the fastest speed at which data can be transferred. These numbers refer to potential capacity in terms of standards, which are rarely achieved consistently in the real world. Kbps, Mbps, and Gbps are measures of bandwidth speed. Gigabytes per second is usually written as GBps, while for gigabytes per second, the "b" is lowercase. A byte has 8 bits, so a download speed of 20 Gbps (20 Gb/s) is 2.5 GBps (2.5 GB/s).

• 5G – 10 Gbps (upload link) to 20 Gbps (download link).
• 6G – 100 Gbps to 1 Tbps.

Average User Experience Data Rate

• 5G – 100 Mbps.
• 6G – 1 Gbps.

peak spectral efficiency

Spectral efficiency measures the amount of data that can be transmitted to a defined number of users or services within a specific bandwidth within a defined geographic area. It is measured in (bit/s)/Hz.

• 5G – 30 b/s/Hz.
• 6G – 60 b/s/Hz.

Average spectral efficiency experienced by the user

• 5G – .03 b/s/Hz.
• 6G – 3 b/s/Hz.

Mobile support

• 5G – up to 500 km/h.
•  6G – up to 1000 km/h.

density

•  5G – 1 device per square meter.
• 6G – 100 devices per square meter.

end-to-end delay

Refers to the time elapsed between a request and a response.

•  5G – 1 to 10 milliseconds.
•  6G - Less than 1 millisecond.

Single frequency full duplex transmission

Full duplex means enabling bidirectional traffic so that data can be sent and received simultaneously on the same frequency, potentially saving 50% of spectrum requirements.

•  5G – no.
•  6G - Supported.

Global coverage

•  5G – 5G has been rolled out in more than 70 countries, with China and the US leading the way.
•  6G – China filed the most 6G patents, followed by the US

in conclusion

The Internet of Things has been around for a while, but 5G is not very efficient due to poor allocation and subsequent overcrowding of some spectrum. 6G aims to expand the range, capacity, speed and energy efficiency of 5G. It is predicted that 6G will largely witness the end of the smartphone era. Instead, it will turn to the use of wearable technology. However, some experts believe that even 6G can't handle wearable Wi-Fi. So, is it possible for 7G to replace the use of 6G?