Abstract :
The distribution of electric field strength in a building close to a MF transmitting tower is investigated by using computer analysis. The moment method is introduced for estimating the shielding effect of a building and for investigating the distribution of the field strength in a building. First, the modeling of a building for computer analysis is described. Then, for confirming the availability of the moment method, a simple model of a building constructed of girders and pillars is introduced. The field distributions in it are calculated by the moment method, and the computational results are compared with experimental results. From the comparison, the availability of the method is confirmed because a good agreement between the computational and the experimental results is obtained. Then the distributions of electric field strength in a number of building constructions are numerically investigated. Lastly, the modeling of a conductive plate such as a deck plate is also discussed. Here the investigating frequency is fixed at 1 MHz (wavelength λ=300 m) in the MF band