Spectrum Management and 5G Technology

Fifth-generation wireless technology (5G) is starting to roll out in cities across the globe—including some in the United States. But most countries are building the new network on a different part of the spectrum than major U.S. cities.

5G is expected to supersede today’s 4G by a huge margin. You might have heard that 5G networks can reach up to more than 10 Gbps of speed with virtually imperceptible lag times. And this is true. However, not all 5G are the same, and that has something to do with spectrum management.

Managing the 5G spectrum

Spectrum allocations are carefully managed today to enable better standards and mitigate the probability of electromagnetic interference (EMI). For 5G, there are three types of spectrums that it needs to run smoothly: the low-band (below 1 gigahertz), the mid-band (1 gigahertz to 6 gigahertz), and the high-band (above 6 gigahertz).

Although low-band radio waves have more coverage—penetrating through walls and obstacles—they carry less data than higher bands. On the opposite end, high-band radio waves can carry more data packets (hence the higher speeds) but have limited coverage and range. This is where the U.S. carriers and firms are building their 5G networks while the rest of the world is using the “Goldilocks” spot—the mid-band.

The type of infrastructure, capabilities, and standards of 5G that companies will invest in depends largely on the spectrum. Technologies like small cell towers, which are low-powered reflecting towers so high-band signals won’t be blocked by obstacles, will be needed. Similarly, the high-frequency capabilities will also require new standards for printed circuit board (PCB) manufacturing to better manage signal integrity challenges. Many of the new devices today, including 5G-enabled smartphones and what we call the Internet of Things (IoT), already use multilayer PCBs. These ensure that signals will remain stable against external fields and noise by suppressing EMI in signal layers. By making these multilayer PCBs high-band 5G-ready, devices can withstand the more frequent cell tower handover. However, only 1 percent of phones today have this capability, and an even smaller number of IoT devices do.

Freeing up bandwidth

In the United States, firms are building 5G in the 24–300 gigahertz area, which is inferior to the “sub-6” or mid-band in terms of range and penetration capability. You see, most of the mid-band spectrum in the country is used by the U.S. Department of Defense, and to use them commercially, you’d have to free them up.

Although the government announced a memorandum in 2018 called “Developing a Sustainable Spectrum Strategy for America’s Future” and through it freed up some radio space, it might not be enough. The government plans to auction around 160Mhz of unused 3.5GHz spectrum to catalyze 5G introduction. Firms today have limited access to the Goldilocks spectrum, and businesses think it will fall short of the projected demand for 5G from both consumers and industries.

Another workaround that organizations are developing, however, has to do with increasing spectrum use efficiency instead. Applications like massive multiple-input, multiple-output (massive MIMO), beamforming, and full-duplex extend the capabilities in a given spectrum by streamlining the effective flow of data packets in coverage while also managing interference.

As the demand for faster and low-latency connections explode given the current global predicament, more 5G spectrum management solutions will need to surface.