As 5G antenna installations are ramped up worldwide, slowly the attention has begun to turn towards 6G. But why all the rush? After all, 5G connectivity is still really only available in the largest metro areas. And it's performance is impressive.
The answer lies in the digital divide, the gaps that can’t quite be filled by the current generation of tower-mounted network technology.
Notably, 6G is still in its early stages of development. No network operators have announced a launch. And it was just last month that a consortium of Japanese device manufacturers announced development of the first 6G compatible device.
But could 6G blanket entire nations and kill off dead zones forever, every single one of them? It’s a tantalizing proposition.
Challenges of 5G networks
The low-latency, high-speed digital connectivity made possible by the fifth generation of communication technology goes beyond text and voice. It's impressive performance has made possible on-to-go gaming for consumers, responsive industrial networks and even has provided unprecedented transparency into shipping, with things like smart shipping containers.
5G today fulfills nearly every real-time digital tracking and device communication requirement demanded by data-dense applications, like edge computing protocols.
However, several shortcomings were addressed with 5G, some which still plagues its rollout. The most glaring of which is 5G antenna density. 5G operates in the millimeter wave frequency and requires closer groupings of antenna arrays within an area to supply the bandwidth and network speed required. 5G waves are more likely to be blocked by urban environments. And due to the mismatch of antenna density required to offered 5G versus population density of rural areas, these places will likely never see a 5G network.
For more information on the technical challenges here, refer to this network bands guide from Nokia. It explains the three band types, low, mid, and high and clarifies the need for contrasting tower configurations setups that suit specific land topographies. Carriers eventually learned to tune high, low and mid-band frequencies for certain situations.
These are not challenges that will inherently be solved by 6G. In fact, the wavelength of 6G is in the sub-terahertz range - even smaller than 5G. However, with time, as with 5G, operators will finesse the technology to supply the anticipated network speed (20 times faster than 5G) with the a suitable range.
Satellites make significant inroads
On a clear night sky, look up and one may see a peculiar sight - a Starlink satellite train soaring overhead through Earth's exosphere. Today, up to 2.7 million users receive their internet connect via a Starlink terminal. For a $2,500 terminal and $500 monthly service fee, users get 150 to 500 Mbit/second data service. And this is available anywhere users have access to open sky - from the middle of the ocean or polar caps or high in the mountains.
In recent years, mobile network operators have agreed with Starlink to add mobile network coverage have satellite constellations. Instead of network towers, hidden to look like trees or perched atop a water tower, users would get service connections to compatible smart devices directly from Starlink satellites.
This required Starlink to develop and launch a second generation of satellites that would support broadband connections to typical mobile devices. This occurred throughout 2022 and 2023 and in early 2024, the first SMS delivered via satellite occurred. However, this required some technical problem solving from the teams, first to ensure satellite data handoffs, and things like Doppler shift and timing delays could be resolved among the satellites. Also, different types of antennas needed to be tested to overcome the mobile unit's low gain and low power transmissions. Finally, at least initially, bandwidths will be limited to a few thousand data transactions per cell.
This technology is at least a year or two from becoming more widely heralded and realistic. But several carriers have signed on with Starlink for service - T-Mobile in the U.S., Rogers in Canada, Optus in Australia and One NZ in New Zealand. All of these nations have substantial backcountry that soon will covered in what T-Mobile is branding "Zero-G," simply due to it's accessibility. In truth, its network speed is similar to that of 3G.
6G via satellite - that's the goal
Dead zones might become a thing of the past with satellite-hosted mobile networks. If the network is orbitally hosted, there are zero towers to worry about, so there would be no land acquisition permits or environmental impact issues, either. No cell towers painted to look like a tree. No arrays perched atop large buildings or water towers.
Satellite-based antenna may deliver 3G like connectivity everywhere, not just where towers can live. But the goal is clearly to build toward a service that can deliver 6G-like speeds. How do we know this? The European Space Agency has told us.
This will be a required technology for innovations like, say, autonomous vehicles. Not only will they be massively data hungry, but its impractical for the autonomous vehicle to go off the grid every time it leaves the city.
Significant 6G hurdles must be leaped. Consider that extremely high frequency (EHF) and terahertz (THz) bands in 6G communications suffer penetration losses from water vapor and oxygen. That's right, clouds could disrupt service.
There is also the challenge of long-distance transmission, although some studies have indicated that technologies like massive MIMO and enhanced beam forming will assume pivotal roles in the standardization and advancement of 6G from space.
