The presented research analyzes the probabilistic characteristics of the Integrated Access and Backhaul system developed by the 3GPP consortium for millimeter-wave wireless networks. This technology addresses the challenges of deploying mobile base stations including those on UAV in densely populated urban areas with high building density and the presence of both mobile and stationary radio signal blockers. The study encompasses the development of a model and scenario for IAB implementation, a GPSS simulator, and an analytical model of a system fragment represented as a polling-based queuing system. The achievable channel bandwidth, the average end-to-end delays, and the average number of packets on the individual routes are selected as the main performance metrics. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.