On the propagation of RF into a building constructed of cinder block over the frequency range 200 MHz to 3 GHz

A study of the RF propagation into a building having a cinder block wall construction is performed by illuminating a two-story structure and recording the levels of the penetrant field over the frequency range 200 MHz to 3 GHz. Internal measurements are acquired at four points on the first floor of the building. Since the building had no windows, the penetration into the building interior occurred primarily as a result of propagation through the walls. The measured internal magnetic field of the illuminated building exhibited a 13-22 dB attenuation for the most part over the frequency range of the study. Multiple reflections from the ground, walls, floor, ceiling, etc., produce notable maxima and minima in the attenuation data as well as several deep nulls in the swept frequency responses.