Vegetation effects of consideration for broadband fixed radio access systems at frequencies above 20 GHz

Broadband fixed radio access (BFRA) schemes have been proposed and adopted to provide high data rate services to homes and businesses. This has led to a demand for information on the effects of the local environment on the radio channel at millimetre-wave frequencies and over the large bandwidths of interest. Studies of the effects of vegetation on radio signals have been documented and have given rise to models of the propagation loss due to the vegetation. More specific studies on the wideband effects of vegetation have been made as part of the ACTS project on "cellular radio access for broadband services" (CRABS) (see CRABS Deliverable Report D3PIB, 1999) and the IST project on "efficient millimetre broadband radio access for convergence and evolution" (EMBRACE) (see EMBRACE Deliverable Report D13, 2002). This paper provides a review of particular aspects of these and aims to give an understanding of the impact of vegetation on the implementation of fixed radio access systems based on measurements for CRABS and EMBRACE area coverage studies (see Seville, A. et al., Millennium Conference on Antennas and Propagation, 2000).