TRANSMISSION AND REFLECTION CHARACTERISTICS AT CONCRETE BLOCK WALLS IN THE UHF BANDS PROPOSED FOR FUTURE PCS

Buildings such as warehouses, supermarkets and retail department store s typically have walls constructed from concrete (cinder) blocks. The web and void design of the individual blocks and their arrangement wit hin a wall creates a periodic structure, which exhibits frequency depe ndent transmission and reflections characteristics in the UHF bands pr oposed for future Personal Communication Systems (PCS). For higher fre quencies, higher order Floquet modes excited at the periodic structure can propagate away from the wall, suggesting that significant power c an be carried away from the wad in non-specular directions. Indoor pro pagation prediction models must consider the nonspecular paths exited by walls with a periodic nature in order to account for all of the sca ttered power. In this work, plane wave reflection and transmission cha racteristics for typical concrete block walls are examined theoretical ly and experimentally to determine the frequency dependence of the spe cularly and non-specularly transmitted and reflected fields.