5G Wireless Backhaul Challenges: Methods to Provide More Efficient and Advanced Wireless Solutions With Higher Capacity


Mobile communications have evolved considerably in recent years. From rudimentary wireless voice systems to advanced smart communications, each generation of technology brings more sophisticated and promising communications systems.

The first in the long line of this technology was 3G. Though old-fashioned now, 3G was once the pinnacle and brought wireless data and anywhere access to the internet for the masses. Without 3G, we wouldn’t have remote work, mobile entertainment, smartphones, or social media, radically changing the world in which we live.

With this advancement in technology comes an increasing demand for a high-quality, seamless internet experience – no matter where or how it’s accessed. 5G is being adopted more and more, which is likely to increase the demand for better online experiences, not only for consumers but businesses.

Benefits of 5G

5G is so exciting because of its ability to improve the way we get information and entertainment. Billions of smart devices can be connected to the internet wirelessly, with privacy, and remote monitoring and control can support IoT devices like self-driving cars, smart buildings and cities, and robotic automation.

5G networks can also enable better content and entertainment, including augmented and virtual reality, social networking, and video streaming.

Understanding Mobile Backhaul Networks

Mobile backhaul networks connect radio access networks (RAN) at the cell sites to a core network. This is how connectivity is offered to the user. Backhaul traffic from the core network to the transmission network requires high capacity, and that’s likely to become more apparent as the technology is widely adopted and becomes more advanced.

As of now, the biggest challenge with 5G is improving network reliability while reducing costs. The capacity requirement of the transmission network from the core network will increase, creating the biggest challenge.

Backhaul wasn’t simple or ideal before 5G. The challenges included long-distance reach, cost, availability, and capacity. 5G only expands on these challenges.

5G will be used to connect IoT devices, including IoT and machine-to-machine devices. Because they collect huge volumes of data that need to be transferred to the core for processing and analysis, they require ultra-low latency for better connectivity, increased capacity for a connected society, decreased congestion, and long-distance reach.

Costs are also a concern for backhaul in general, not just 5G. No method of wireless backhaul offers a solution for all the challenges, but many can strike a balance with the right circumstances.

5G Wireless Backhaul Solutions

Several factors go into choosing a backhaul solution, including latency requirements, quality of service, expense, and load intensity. The conditions for backhaul also vary and impact the performance of the solution.

Wireless backhaul can be categorized according to several parameters:

  • Reach – from several hundred feet to over 150 miles
  • Frequency – bands from 4 GHz to 200 GHz
  • Backhaul architecture – point-to-point (PtP) or point-to-multipoint (PtMP)
  • Traffic type – TDM, hybrid TDM-IP, all-IP
  • RAN architecture – backhaul, mid-haul, or front-haul
  • Node configuration – split-mount, indoor, all-outdoor, disaggregated

Fiber Backhaul Solution

Fiber backhaul is the go-to solution for high capacity, high reach, and low bit error rates. It’s not available everywhere, however. When it is available, it’s a popular choice for addressing multiple requirements for backhaul.

Fiber isn’t without any limitations, of course. It can’t travel through obstacles like buildings or natural features, without a pathway. It also takes a long time to deploy – often months – compared to solutions that can be up and running in a matter of days or a week. Fiber is expensive as well.

Wireless Backhaul Solutions

Backhaul traffic from a radio switch to a cell site can be done wirelessly, which opens an opportunity to approach wireless backhaul. This solution is reliable and cost-effective, giving operators end-to-end control and monitoring of networks.

Wireless backhaul may be more susceptible to performance issues from external factors, such as cell site location, energy efficiency, the availability of the spectrum, environment, and traffic.

The three options for wireless backhaul include:


Wireless backhaul technology is currently in use for about half of mobile traffic, and microwave radiofrequency accounts for most of that. Though it can be expensive for the initial investment and deployment, it’s a more cost-effective and faster option overall.

Microwave radiofrequency backhaul is vulnerable to changes in weather conditions and climate, however. Operators can adjust the transmission rate to address availability requirements, such as choosing the higher frequency band for a better data rate.

The downside is that this comes with a tradeoff. Choosing a higher frequency band has lower reach, but better performance. Conversely, choosing a lower frequency band to improve the reach increases network congestion.

Millimeter Wave

Millimeter wave has a high-frequency range, usually around 30 GHz to 300 GHz. This method is beneficial for small cell backhaul solutions for its spectrum and ability to handle high data rates. This comes with a shorter reach. Millimeter wave beams are also narrower than microwave beams, which impacts the line of sight.

Free Space Optics

Free space optics works similarly to fiber optics but without the cable. It uses invisible light beams, such as light-emitting diodes (LEDs) for data transmission. The greatest advantage of free space optics is that it has a wide spectrum in the range of 300 GHz to one THz. The rate is also up to 10 Gbps. Compared to other methods, free space optics has lower consumption.

Though it’s the best of both worlds, free space optics has limitations in line-of-sight communications, which can suffer in fog or other weather conditions, as well as from ambient light sources. Physical obstructions also present a problem. Despite these cons, free space optics is still among the best options for scalability and flexibility.

Wireless Backhaul for 5G

The whole of mobile communications is evolving and growing rapidly with the help of single board computers (SBC) like the NXP IMX8. 5G is experiencing wider adoption, fueling the need for wireless backhaul methods that address the requirements of the network and offer impressive performance, but there’s no one-size-fits-all solution. Selecting the right wireless backhaul solution for 5G requires balancing the advantages and disadvantages.

Jason is the Head of SEM at SolidRun which is a global leading developer of embedded systems and network solutions, focused on a wide range of energy-efficient, powerful, and flexible products which help OEMs around the world simplify application development while overcoming deployment challenges