Question

A wireless computer network transmits data across the space between nodes as a modulation of a 2.45 GHz (microwave) carrier signal. The signal is able to pass through a brick wall that is 100 mm thick. Recent measurements have determined that the dielectric function at microwave frequencies for the material of a typical building brick is Eneal +1 εǐnag = 5.86 + 0.681, ε and the relative permeability is unity Is there a way of calculating this not using conductivity but by reflection and absorbtion? (d) Show that in passing perpendicularly through 100 mm of brick only about 16% of the incident energy emerges. (Multiple reflections can be ignored but transmission across both interfaces must be taken into account.) (12 marks)

Answer 1

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