According to data from Omdia and TeleGeography, the number of 5G connections and 220 commercial networks worldwide is expected to exceed 540 million by the end of 2021. What do these numbers mean for engineers, system designers, and others responsible for adding cellular connectivity to their devices and workflows?
One key point is the benefit of volume-driven growth. The more devices and networks there are, the faster 5G will reduce its cost curve. This makes 5G increasingly feasible for price-sensitive applications such as the Internet of Things and consumer electronics.
This trend seems like a clear signal to start using 5G instead of 4G. And to a large extent, that's true. But it's not that clear. Here's why—and six key things to consider when deciding whether, when, and how to start using 5G.
Browse spectrum options
Spectrum selection directly impacts your product's performance, reliability, battery life, carrier selection, target market, and cost. 5G is designed to operate across 63 frequency bands, far exceeding any previous generation. These bands range from 600 MHz to 48 GHz, many of which extend far beyond traditional cellular bands. This means that even if you have experience integrating cellular modems into your devices, 5G still presents a steep learning curve.
For example, each frequency band has its own signal propagation characteristics and bandwidth capabilities. Millimeter wave (mmWave) spectrum—24 GHz and above—supports multi-gigabit speeds and is ideal for bandwidth-intensive applications such as 4K video surveillance camera backhaul or streaming 8K video to street-side digital signage.
It's important to note that mobile operators typically deploy millimeter-wave base stations only in certain areas, such as city centers, shopping malls, business parks, and stadiums. This is because higher frequencies have shorter signal ranges, meaning operators must deploy more sites to cover a given area. A millimeter-wave base station on a lamppost might only have a coverage range of a few hundred meters. Only densely populated areas have a large enough potential customer base for operators to recoup the capital and operating costs of all these additional sites.
What if the app needs gigabit speeds in other places like small towns and interstate highways? Then its 5G module must support other lower frequency bands to ensure connectivity is always available. This might also require carrier aggregation (CA), where multiple signals from multiple frequencies are combined to achieve the target bandwidth.
Another factor is physical barriers. At higher frequencies, walls, windows, and even leaves can attenuate signals to the point of drastically reducing bandwidth—or causing a complete loss of connection. This is why it's important to consider where the device will be used: indoors? outdoors? both? The same question applies to 5G base stations. For example, if the device is used indoors, such as in factory automation, if the base station is also indoors, rather than trying to send a signal through an exterior wall, the throughput will be more consistent and the connection more reliable.
Who owns the 5G network?
Factory automation scenarios highlight another key consideration: who owns the 5G network your equipment will use? If the product is targeted at the commercial market, it can be a dedicated network, which can take one of the following three forms:
Enterprises own their core and radio access network (RAN), just like mobile operators.
The company uses virtual private slices of public 5G networks operated by mobile carriers.
• A hybrid approach where enterprises own their local networks but also use private slices of public 5G networks for wide-area coverage.
Mobile operators have access to more frequency bands than private operators. For example, in the United States, private networks may use the CBRS spectrum (3.55 to 3.7 GHz), also known as Band 48. Therefore, if a device is targeted at U.S. businesses with 5G networks, its modules and antennas must support CBRS.
Another consideration is 5G availability, especially if some target customers use virtual slicing or hybrid combinations of public networks. While approximately 220 5G networks were in commercial service by the end of 2021, it will take several more years to match the nearly 700 4G networks currently available. In fact, TeleGeography estimates that by the end of 2023, 5G will still be less than half available, with approximately 329 networks globally.
Therefore, the module will need to support 4G for use in areas where 5G standalone networks (public or private) are not yet available. This feature, known as "dual connectivity" or EN-DC, increases the module's complexity, which in turn introduces additional challenges and costs associated with regulatory approval and mobile operator certification.
Pre-certification can reduce development time and costs.
Even if the module doesn't require 4G support, certification is a critical consideration because it impacts the cost and delivery time of bringing 5G products to market. To minimize both of these impacts, look for 5G modules that have been pre-certified by major mobile operators and regulatory bodies such as the Federal Communications Commission (FCC), the PCS Type Certification Review Board (PTCRB), the Radio Equipment Directive (RED), the Global Certification Forum (GCF), the Japanese Radio Law (JRL), the Japanese Telecommunications Business Law (JTBL), and the Korea Communications Commission (KCC).
Certifications from operators and regulators also impact the potential market and revenue potential of 5G equipment. The more certifications a company has, the more countries and regions it can sell in. This flexibility is particularly attractive to multinational corporate clients.
Power consumption: Less means more
Many 5G applications will involve battery-powered devices, such as medical wearables and industrial sensors. In these cases, power consumption is a major consideration, especially if the application is mission-critical or if the device is expected to remain unchanged for a decade.
The 5G standard includes features designed to maximize battery life. For example, 5G can transmit data faster than previous generations, so devices spend less time—and therefore less energy—sending and receiving. Multiple-input multiple-output (MIMO) antenna technology also increases signal strength, which helps minimize packet loss and thus reduces the need for retransmissions.
However, there are many additional considerations that can further extend battery life. Some of these depend on other options, such as spectrum. For example, if 5G devices will use millimeter-wave spectrum, the module should be paired with a low-power antenna.
Check speed specifications
5G is synonymous with speed. For example, the 3GPP 5G standard includes an enhanced mobile broadband (eMBB) feature set, supporting peak downlink speeds of 10 Gbits/s. Impressively, for many 5G applications, such as backhaul for surveillance cameras and SD-WAN in enterprise offices, the uplink capability of the module will be just as important or even more crucial.
Another speed-related nuance involves the aggregation of CA and EN-DC. Carefully examine the combination of EN-DC and CA for your modules to ensure they don't impose performance limitations in real-world deployments. For example, due to the lack of EN-DC aggregation, 5G performance can sometimes even be lower than 4G in certain areas.
Maximize the value and lifespan of 5G modules
A well-designed 5G module can also reduce the device's bill of materials (BOM) cost, potentially improving profitability. Lower BOM costs can also allow the device to penetrate a larger market, including price-sensitive IoT applications such as smart meters.
For example, modules with powerful processing capabilities can also run user-space applications without requiring separate hardware. This could also present opportunities to leverage embedded application development environments, such as a set of functions that can be invoked by a Linux client application.
Finally, consider the physical environment of the device. For example, if it will be affected by large temperature fluctuations and vibrations (such as a fleet telematics module), choose an industrial-grade module. Look for a temperature range of -40˚C to 85˚C, and a thermal design for effective heat dissipation. Avoid using modules designed for consumer devices such as laptops, tablets, and mobile hotspots.
