EMBEDDED ANTENNAS IN DRY AND SATURATED CONCRETE FOR APPLICATION IN WIRELESS SENSORS

E-cient embedded antennas are needed for future wireless structural health monitoring. The input return loss and transmission losses of a dipole, a planar inverted-F antenna (PIFA), a microstrip patch, and a loop antenna are studied at around 2.45GHz when these antennas are embedded inside a concrete cylinder. Antenna performance is investigated in free-space, in air dried concrete and in saturated concrete with and without the presence of steel reinforcements. It is observed that the maximum transmission loss for a distance of 250mm between antennas is around 50dB which is acceptable for inside the bridge wireless communication between sensors.

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