  The unlicensed spectrum is recently considered one of the defining solutions
to meet the steadily growing traffic demand. This, in turn, has led to the
enhancement for LTE in Release-13 to enable Licensed-Assisted Access (LAA)
operations. The design of the medium access control (MAC) protocol for the LAA
system to harmonically coexist with the incumbent WLAN system operating in an
unlicensed band is critical and challenging. In this paper, we consider an
Integrated Access and Backhaul (IAB) system coexisting with a Wi-Fi network
operating at millimeter-wave (mmWave) unlicensed spectrum, for which a
listen-before-talk-based (LBT) based medium access mechanism is carefully
designed. Additionally, we have considered an in-band system that supports both
access and backhaul in a single node where the small-cell or the IAB nodes
compete with the WiGig for medium access. We present comprehensive experimental
results and give design insights based on the simulation results.
