Statistical distribution of parameters in a variable delay two-ray propagation model

Propagation data obtained from a 6-GHz channel with a 30-MHz bandwidth over a 23.3 mile path are used to obtain the statistics of parameters of propagation for two models, namely, the two-ray model and W.D. Rummler´s (1979) model. Only scans with both an in-band notch and an in-band power difference greater than 1 dB are considered. It is noted that the statistics of the relative delay between rays is important because the mean of this delay is directly related to the severity of the dispersive fading and the outage time of the system. The results show that the relative delay of the second ray in the two-ray model can be best approximated by a gamma distribution