In ways both subtle and sublime, 5G technology is poised to empower transformational opportunities that will benefit telecom service providers and consumers alike. While many consumers expected 5G to be a revolution, those deploying the technology know it is more about an evolution, which encompasses clearing a series of technical hurdles to drive significant advantages.
After all, incrementally updating existing networks to enable a successful transition is nowhere near as fun as capitalizing on all the cool bandwidth-gobbling applications promised ahead. Achieving this reality has put some formidable design challenges in front of engineers, most notably in addressing backhaul infrastructure and network architecture as well as the manufacturing of transistors and connectors.
A recent survey commissioned by Molex revealed that more than half of those polled across the ranks of network operators or mobile virtual network operators (MVNOs) expect 5G to deliver substantial end-user benefits within two to five years. When asked to identify the most important technology or industry changes that will enable network operators to achieve their business goals, respondents cited reduced costs of 5G infrastructure and network equipment (41%); innovation in enabling technologies, including semiconductors and sensors (31%); availability of new types of devices that require connectivity (26%); and stable and consistent government regulations (22%).
Survey respondents also identified spectrum issues (41%), lack of consumer use cases (31%), and regulations (30%) as the top three challenges slowing progress today. Luckily, those hurdles did not diminish enthusiasm or derail overall plans for making the next generation of wireless communications a reality.
In fact, there seems to be growing consensus that the following top five technology enablers are primed to accelerate 5G’s growth trajectory.
1. Radio Access Network Architecture
The emergence of new 5G applications coincides with a growing role for flexible front-haul solutions to meet 5G’s throughput, latency, and reliability needs. Next-generation Option 7.2x split radio access network infrastructure is being deployed to deliver the fiber-based link between radio units (RUs), distributed units (DUs), and centralized units (CUs). The 3GPP 5G Option 7.2x standard permits splitting some 4G LTE baseband functions between the DU and CU. DUs typically are located at a far edge location, no more than 20 miles from the RU. CUs can be deployed at edge locations, which are much farther from the DU, because CU functions are not latency sensitive.
Expect much of the front-haul transport to utilize high-efficiency enhanced CPRI (eCPRI) protocol, which employs a methodology that decreases bandwidth requirements from the RUs to the DUs. The result: better performance at costs lower than technologies delivering 4G services.
2. Flexible Backhaul
5G requires service providers to invest in the underlying infrastructure of their mobile networks. Most notable are the front- and mid-haul layers, which connect cell sites and the public network. As growing numbers of traffic cells are deployed to deliver increasingly large amounts of data to the core network, flexibility in systems integration is needed to meet both capacity and latency requirements.
Optical fiber backhaul supports the requirement to transport significant bandwidth while also mitigating issues regarding weather and multi-path propagation. Deploying fiber to buildout a radio access network is not always possible. Additionally, construction timelines might not match deployment requirements, and, sometimes, cost is simply prohibitive. In this instance, leasing capacity from another provider is the first option. If a leased capacity fiber-based solution is not possible, two air solutions could be used: integrated access backhaul (IAB) and/or microwave. Both come with their own share of trade-offs; they neither support the bandwidth of fiber nor do they have the same reach, but they could shorten deployment times. The myriad of choices gives providers additional flexibility when it comes to choosing the optimal backhaul technology for their network.
3. High-Power Density Transistors
5G RUs implement multiple-input, multiple-output (MIMO), phased-array antenna architectures to deliver the highest possible data rates between the radio and end-user equipment. The tightly clustered antenna configurations needed for large MIMO architectures create significant performance challenges for electronic components. At higher frequencies, such as those used in deployments of mmWave option 2 split architectures, the physical distance between antenna elements often is small.
In addition, the shorter the wavelength, the smaller the antenna needed to capture the wavelength. This means more antenna elements can be placed on the array. As a result of more antenna elements and higher frequencies, more power will be needed for the communications subsystems. Because of this, RF power and heat dissipation become a formidable reality that demands the latest innovations in system design and materials. This is why more engineers are embracing fourth-generation, gallium nitride-based, field-effect transistors. This solution features higher power densities to empower the smaller packages required for massive MIMO architectures.
4. Smart Connectors
Millions of bits traversing multiple components at 5G speeds inside consumer-grade products require the smartest and savviest of engineering solutions. After all, high-frequency 5G signals demand all interconnections, board traces, cable assemblies and connectors be of superior quality. In particular, this means connectors must be designed and manufactured to be able to minimize impedance variations during transmission.
Connectors also must be impervious to external signals from all kinds of electromagnetic interference. The challenge is only multiplied by the fact that 5G connectors also must be designed to fit into the small form factors of today’s mobile devices. Stacking connectors is a must for the densely populated flexible and rigid circuit boards, so it is imperative that connectors are designed to minimize reflections, degradation and signal distortion. At the same time, connectors must be adequately shielded to reduce electromagnetic interference.
5. Advanced Manufacturing
Delivering maximum performance from the small spaces is an ongoing challenge for 5G design engineers, so manufacturers should rely on the latest molded interconnect device/laser direct structuring (MID/LDS) techniques. This is necessary to achieve the tight integration of complex 3D electrical and mechanical structures. Existing 2D simply cannot deliver the kinds of devices that consumers demand — those high on capabilities while being small and lightweight.
Combining the versatility of MID’s two-shot molding process with the precision of LDS results in compact, high-density applications that meet 5G device guidelines. These technologies are business-critical for 5G device manufacturers looking to address miniaturization without compromising performance.
What’s Ahead for 5G?
For 5G to meet its maximum potential, a steady stream of innovations and investments will be required from all involved parties. Despite any setbacks that could be attributed to the pandemic, optimism prevails, as according to the survey, 92% of respondents expect to achieve their business goals within five years.
Challenges do remain, especially for design engineers who must create new 5G products that can be mass produced efficiently and affordably while meeting customer expectations. The onus remains on selecting the most appropriate and functional 5G components, testing all along the way, and then expertly integrating them into small form factors.
That is why it remains of utmost importance for engineers globally to build the benefits of 5G into a broad range of applications, including gaming, virtual reality, autonomous cars, and wireless surveillance, to name a few. In each case, 5G is expected to drive innovative new business models, as companies start to take advantage of enhanced connectivity.