Effects of lossy background and rebars on antennas embedded in concrete structures

In this letter the effects of a lossy background on an antenna for wireless embedded sensors network has been studied. The efficiency of the antenna versus the concrete structure size decreases from 72% down to ∼20%. However, it is shown that the boresight gain is essentially unaffected by the block size. The proposed configuration is robust against concrete permittivity variations, change in block dimension and presence of rebars.