Determination of the Effective Electromagnetic Parameters of Complex Building Materials for Numerical Analysis of Wireless Transmission Networks

Abstract

In this paper, we present the method for determination of effective electromagnetic parameters of complex building materials. By application of the proposed algorithm, it is possible to analyze electromagnetic field distribution for large-scale problems with heterogeneous materials. The two-dimensional numerical model of building components (hollow brick) with periodic boundary conditions was solved using the finite-difference time-domain method (FDTD) and discussed. On this basis, the resultant transmission coefficient was found and then the equivalent relative permeability and electric conductivity of heterogeneous dielectric structures, in the developed homogenization algorithm, were identified. The homogenization of material properties was achieved by performing a multi-variant optimization scheme and finally, selecting optimal electric parameters. Despite the analysis of heterogeneous building materials, the presented algorithm is shown as a tool for the homogenization of complex structures when scattering of a high-frequency electromagnetic field is considered.

Influence of a Medium on Capacitive Power Transfer Capability

“…The materials used in this analytical comparison are listed in Table 1 with their dielectric constants. [11] Brick 3.3 [12] Rockwool 4.7 [13] Concrete 4.96 [14] Glass 7.6 [15] Water 80.103 [16] A first finding here is that the resulting CM with water as a medium is much higher, 80 times according to dielectric constant, than in air. Even typical building materials like glass or rockwool lead to a significantly higher resulting capacitance, 3 to 8 times greater at a distance of 10 mm.…”

Comparison of the Moist Material Relative Permittivity Readouts Using the Non-Invasive Reflectometric Sensors and Microwave Antenna

“…According to Pinhasi et al [ 73 ], the value of dry red brick real permittivity equals 3.3 and the brick wall permittivity equals 3.56. Choroszucho et al [ 74 ] stated that the value of dry brick permittivity equals 4.4, while Kaiser et al [ 75 ] evaluated the permittivity of red brick at the level of 4.1. A comparison of relative permittivity of moist bricks is hindered by the different water absorptivity of materials.…”

Modulation of dielectric properties in low-loss polypropylene-based composites at GHz frequencies: theory and experiment

“…Therefore, a better approach is to perform full-wave electromagnetic simulations. The reported calculations usually consider either a capacitor in the quasi-static regime with a well-defined electric potential 12 , 15 – 17 or microwave propagation through a slab or periodic unit cell of the composite 13 , 14 , 18 , 19 . Multiple methods have been used in the literature to define and extract effective composite permittivity with such simulation.…”