Wireless backhaul in future heterogeneous networks

Heterogeneous networks are an effective way of expanding networks to handle traffic growth. However, the additional small cells included in heterogeneous networks need to be provided with backhaul – in a way that is flexible and cost-efficient. Our research shows that non-line-of-sight (NLOS) backhaul in licensed spectrum up to 30GHz is a future-proof technology for managing high volumes of traffic in heterogeneous networks.

The best physical location for a small cell often limits the availability of wired backhaul. In urban areas, small cell outdoor nodes are likely to be densely deployed, mounted on lampposts and building facades. Fiber, if it exists, is the best option for backhaul. But in many cases, the ideal placement of small cells limits its availability.

So, Ericsson has carried out a study to determine the impact on user performance in a heterogeneous network when backhaul is provided to the small cells over a wireless link, by comparing it with a system where backhaul is provided over fiber.

Through system simulations the joint impact of backhaul and access technologies on user performance were captured. Two different backhaul solutions were tested: a commercial high-end point-to-point microwave backhaul and an LTE-based point-to-multipoint concept – at 6GHz and 28GHz. Both technologies were assumed to operate in licensed microwave bands.

The results showed that NLOS backhaul in licensed spectrum up to 30GHz can provide user performance on a comparable level to a fiber-based solution.

Wireless backhaul in future heterogeneous networks