This paper reports the propagation measurements conducted in urban, suburban, and rural environments of Singapore at 27.4 GHz and the studies on excess loss, K-factor, mean delay, and delay-spread characteristics. Also, static and time-variant channel impulse response (IR) models, developed based on measurements, were reported. The static channel IR models were classified into good, moderate, and bad channel types according to the signal reception quality. A generalized tapped delay-line model was presented to represent the time-varying complex channel IR. Finally, simple channel IR simulations were carried out to compare the delay characteristics with the measured results.Index Terms-Channel model, delay spread, excess loss, LMDS.