Search for: All records

Outdoor-to-indoor (OtI) signal propagation further challenges the already tight link budgets at millimeter-wave (mmWave). To gain insight into OtI mmWave scenarios at 28GHz, we conducted an extensive measurement campaign consisting of over 2,200 link measurements. In total, 43 OtI scenarios were measured in West Harlem, NewYork City, covering seven highly diverse buildings. The measured OtI path gain can vary by up to40dBforagivenlink distance, and the empirical path gain model for all data shows an average of 30dB excess loss over free space at distances beyond 50m, with an RMSfitting error of 11.7 dB. The type of glass is found to be the single dominant feature for OtI loss, with 20dB observed difference between empirical path gain models for scenarios with low-loss and high-loss glass. The presence of scaffolding, tree foliage, or elevated subwaytracks, as well as difference in floor height are each found to have animpact between 5–10dB. Weshowthatforurbanbuildings with high-loss glass, OtI coverage can support 500Mbps for 90% of indoor user equipment (UEs) with a base station (BS) antenna placed up to 49m away. For buildings with low-loss glass, such as our case study covering multiple classrooms of a public school, data rates over 2.5/1.2 Gbps are possible from a BS 68/175m away from the school building, when a line-of-sight path is available. We expect these results to be useful for the deployment of mmWave networks in dense urban environments as well as the development of relevant scheduling and beam management algorithms.