REFLECTION AND TRANSMISSION CHARACTERISTICS OF RADIO-WAVES AT A BUILDING SITE DUE TO REINFORCED-CONCRETE SLABS

The structure of reinforced concrete (RC) slabs ata building site chan ges from reinforced iron-bar mesh and concrete to many kinds of concre te walls as construction is completed. As the structure changes, its r adio characteristics also change. It is very important to know such ch aracteristics;as radio;wave reflection, wave penetration, and wave sca ttering of concrete in order to use mobile phone and other radio syste ms at the construction site. This study tries to establish a practical ly useful scheme to obtain radio characteristics from a simulation exp eriment using a scale model and electromagnetic analysis. We first ana lyze the reflection and transmission characteristics, the complex diel ectric frequency characteristics of the concrete, and the dependency o f these characteristics on the percentage of water included iii the co ncrete. Taking into account the characteristics of the multilayer diel ectric model, we carried out an experiment and-did calculations for ob taining the characteristics of the basic iron concrete wall, and the v alidity of the scheme was confirmed. (C) 1998 Scripta Technica.