5G is no longer just a promise—it’s very real, even though implementation is in its infancy. There are two examples from 2019 that demonstrate that 5G implementations are materializing. One is that Verizon launched 5G service in all its NFL football stadiums. The other example is that in South Korea, 5G subscribers reached more than 2 million by August of that year – just four months after local carriers commercially launched the technology. In this post, we explore what’s advancing 5G in these areas such as small cell densification, spectrum gathering, spectrum sharing and massive MIMO. Although it will take time to become ubiquitous, 5G is expected to be the fastest-growing mobile technology ever. According to the Global Mobile Supplier Association (GSA), 5G is expanding at a much faster pace than 4G LTE—approximately two years faster. GSA recently published data stating that more than 50 operators launched 5G mobile networks and at least 60 different 5G mobile devices are available across the world.

To obtain the bandwidth in FR1 and FR2, more spectrum must be allocated. Already, regulators in roughly 40 countries have allocated new frequencies and enabled re-farming of LTE spectrum. However, much more will be needed. To provide at least some of that, 54 countries plan to allocate more spectrum between now and the end of 2022, according to the GSA.

3. 4G to 5G Network Progression

5G Radio Access Network (RAN) is designed to work with existing 4G LTE networks. 3GPP allowed for multiple New Radio (NR) deployment options. Thus, making it easier for MNOs to migrate to 5G by way of a Non-Standalone (NSA) to Standalone (SA) option, as shown in the figure below.

4. Dynamic Spectrum Sharing

Dynamic spectrum sharing (DSS) is a new technology that can further help smooth the migration from 4G to 5G. With DSS, operators can allow 4G and 5G users to share the same spectrum, instead of having to dedicate each slice of spectrum to either 4G or 5G. This means operators can use their networks more efficiently and optimize the user experience by allocating capacity based on users’ needs. Thus, as the number of 5G users increases, the network can dynamically allocate more of the total capacity to each user.

5. Millimeter Wave (mmWave)

5G networks can deliver the highest data rates by using mmWave FR2 spectrum, where large expanses of bandwidth are available. mmWave is now a reality: 5G networks are using it for FWA and mobile devices and will apply it for other use cases in the future. Operators expect to roll out FWA to more homes, as 5G network deployment expands and suitable home equipment becomes available.

6. Massive MIMO

MIMO (multiple-input and multiple-output) increases data speeds and network capacity by employing multiple antennas to deliver several data streams using the same bandwidth. Many of today’s LTE base stations already use up to 8 antennas to transmit data, but 5G introduces massive MIMO, which uses 32 or 64 antennas and perhaps even more in the future. Massive MIMO is particularly important for mmWave because the multiple antennas focus the transmit and receive signals to increase data rates and compensate for the propagation losses at high frequencies. This brings huge improvements in throughput and energy efficiency.

7. RFFE Innovations that Enable 5G

Innovation in RF front-end (RFFE) technologies are needed to truly enable the vision of 5G. As handsets, base stations and other devices become sleeker and smaller, the RFFE will need to pack more performance into less space while becoming more energy-efficient. Some RF technologies are key in achieving these goals for 5G. They include:

• Gallium Nitride (GaN). GaN is well suited for high-power transistors capable of operating at high temperatures. The potential of GaN PAs in 5G is only beginning to be realized. Their high RF power, low DC power consumption, small form factor, and high reliability enable equipment manufacturers to make base stations that are smaller and lighter in weight. By using GaN PAs, operators can achieve the high effective isotropic radiated power (EIRP) output specifications for mmWave transmissions with fewer antenna array elements and lower power consumption. This results in lighter-weight systems that are less expensive to install.
• BAW Filters. The big increase in the number of bands and carrier aggregation (CA) combinations used for 5G, combined with the need to coexist with many other wireless standards, means that high-performance filters are essential to avoid interference. With their small footprint, excellent performance, and affordability, surface acoustic wave (SAW) and bulk acoustic wave (BAW) filters are the primary types of filters used in 5G mobile devices.