A wireless computer network transmits data across the space between nodes as a modulation of a 2.45GHz (microwave) carrier signal. The signal is able to pass through a brick wall that is 100mm thick. Measurements have determined that the dielectric function at microwave frequencies for the material of a typical building brick is epsilon=epsilon(real) +i epsilon(imaginary)=5.86+0.68i, and the relative permeability is unity.

Show that in passing perpendicularly through 100mm of brick only about 16 percent of the incident energy emerges. (Multiple reflections can be ignored but transmission across both interfaces must be taken into account.)