Ultra-Reliable High-Capacity Wireless Backhaul
TL;DR
An approach based on ITU rain-attenuation models predicts the capacity that wireless point-to-point links can guarantee at different reliability levels and finds that combining high and low bands can enable ultra-reliable operation, albeit with reduced capacities, while relaying improves guaranteed capacity at moderate reliability levels but cannot ensure ultra-reliability.
Abstract
Wireless backhaul is a cost-effective alternative to fiber in mobile networks. However, meeting rising reliability and capacity requirements over wireless point-to-point links remains challenging as the high-frequency links required for multi-Gbps transport are highly sensitive to precipitation. To quantify this effect, we develop an approach based on International Telecommunication Union (ITU) rain-attenuation models that predicts the capacity that wireless point-to-point links can guarantee at different reliability levels. Using frequency bands and system parameters representative of current deployments, we evaluate the impact of climate and link distance on guaranteed capacity. Our results show that in rainy regions, higher-frequency bands cannot deliver ultra-reliable capacity for typical link distances. Motivated by this, we assess two mitigation strategies: combining capacity from multiple bands and multi-hop relaying over shorter distances. We find that combining high and low bands can enable ultra-reliable operation, albeit with reduced capacities, while relaying improves guaranteed capacity at moderate reliability levels but cannot ensure ultra-reliability.