Integrated Access and Backhaul (IAB) is a significant innovation in 5G technology. It introduces a new type of wireless backhaul known as integrated access and backhaul that is of particular interest for dense deployment of street-level radio nodes.
The key concept behind IAB is in reusing the existing 5G framework for both access link and backhaul. This is particularly useful for 5G millimeter wave (mmWave) spectrum deployments, which require greater cell density.
The mmWave radio resources can only provide limited coverage, which makes it reasonable to expect a fairly low level of utilization. As a result, there is an opportunity to use an innovative type of wireless backhaul in 5G – integrated access and backhaul (IAB) – to densify networks with multi-band radio sites at street level.
In a 5G IAB topology, some base stations with wired backhaul act as IAB donors. The remaining base stations are IAB nodes, transmitting backhaul via donors.
IAB uses the same wireless channel for coverage and backhaul connectivity to other base stations, which leads to greater performance, more efficient use of spectrum resources and lowers equipment costs, while also reducing the reliance on the availability of wired backhaul at each access node location.
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