METALS are commonly used in antenna structures for the
radiating elements and the ground plane. However, for
some applications, cost, fabrication procedure, weight, or corrosion
resistance can limit the usefulness of metal antennas. Some
recent studies have used various composite materials as replacements
for metals [1]–[5]. In [1], a conducting-polymer patch
antenna is proposed. Silver nanoparticle ink [2] and metallo-organic
conductive ink [3] have been used to prepare a highly conductive
material. In [4], metallized foam is used to make a microstrip-
patch antenna.