Voice transport stills emerging in modern communication systems, going ahead from a specific located service to a more personal, with most of people having a mobile phone. Data transport is the development area that, through the Internet Protocol (IP), will allow a lot of opportunities on the business market. Data and the new applications that will emerge will be the key to new yields in wireless communications. A lot of data transport services through IP are being developed, operating on a frequency band higher than the one used by the existent cellular mobile systems. Actually there are a lot of emerging FWA (Fixed Wireless Access) services in the 3.5 GHz band with support to IP. Then, the study of the behaviour of an electromagnetic signal in 3.5 GHz is a very important issue because new and important applications are emerging and being developed in this band. In order to carry out this task, a fixed to mobile link was assembled and a lot of experimental work was performed on two different sites of Rio de Janeiro city. The results presented in this work deal with path- loss measurements for coverage prediction and the study of received signal variability essential on system parameter determination. The results are compared with the most popular empirical and statistical models in the literature. The conclusion of this work suggest that new prediction models for path-loss determination and new distribution functions are needed mainly for systems parameters like level crossing rate (LCR) and average fading duration (AFD).