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Measurements and propagation models for building penetration are shown for a VHF/ UHF system that uses low antenna height (< 3 meters). Measurements show that excess building loss, even when line-of-sight conditions exist, can easily exceed 30 dB. Additionally, variations of the channel frequency response in excess of 20 dB were observed over a 5 MHz bandwidth. Also, paths with maximum excess delays (25 dB) up to 5.2 µ seconds were observed. These factors as well as others presented in detail in this document will have a significant impact on the air interface specification for the cognitive radio inbuilding communication system. Index Terms-VHF/ UHF Propagation, VHF/ UHF Delay Spread, Propagation through build ingress, dynamic spectrum access.