Integrated Access and Backhaul

A conventional small-cell deployment requires two separate pieces of infrastructure at every site: the radio equipment serving nearby user devices, and a dedicated backhaul connection — fiber or point-to-point microwave — carrying that site's traffic back to the core network. IAB collapses these into a single radio system: the same base station serves users directly and simultaneously relays its backhaul traffic wirelessly to a nearby parent node, which may itself be fiber-connected or relay further through another IAB hop, trading dedicated backhaul infrastructure for shared spectrum capacity between the two functions.

The deployment economics IAB changes are specifically about removing the civil-works bottleneck that has historically constrained dense small-cell rollout — trenching fiber to every new small-cell site is slow, expensive, and often the actual limiting factor on how quickly a dense network can be built, far more than radio equipment cost itself, and IAB directly addresses this by making a wireless radio deployment self-sufficient for backhaul rather than dependent on parallel civil-works progress. This is precisely why IAB adoption has concentrated around mmWave densification specifically: mmWave's short range already demands a very high site density, multiplying the fiber backhaul cost problem proportionally, and IAB's ability to remove that dedicated backhaul requirement at each site is most valuable exactly where that multiplication effect is largest. For CE verticals, IAB is most relevant to rapid or cost-constrained dense-coverage deployment scenarios — extending high-capacity coverage into an area without existing fiber infrastructure, or accelerating rollout timelines where waiting for civil works would otherwise be the binding constraint — though the shared access-and-backhaul capacity tradeoff means IAB deployments need realistic capacity planning rather than being treated as capacity-equivalent to dedicated-backhaul alternatives.