Comparison of Fade Models for LMDS

There are differences between the two most popular models, ITU terrestrial model and Crane model. Crane has produced three models; the Crane Global model, Crane two-component model, and revised Crane two-component model that produce slightly different estimates of the long term mean fade probability. The Crane models tend to produce higher attenuation than the ITU model. But the uncertainty of either of these models or alternatively the short-term expectation of fade is quite large. Uncertainty stems from variations from year-to-year and location-to-location. The complexity of each model is also discussed. Purpose By describing the various rain propagation models and comparing results from the models, an input to section 5 of the outline can be generated. Notice This document has been prepared to assist the IEEE P802.16. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release The contributor acknowledges and accepts that this contribution may be made publicly available by 802.16. 1999-09-10 IEEE 802.16cc-99/13 -2 -Comparison of Fade Models for LMDS William Myers