Contents I. Introduction
Miniaturization of microstrip patch antennas (MPAs) is a very challenging field to investigate due to the increasing interest in integrating such antennas in MMIC circuits. The conventional dimensions of MPAs are around a half waveguide wavelength. Several miniaturization techniques are appearing to reduce such dimensions. These techniques can be classified in: 1) use of high permittivity substrates; 2) use of magnetic substrates; 3) increase electrical length; 4) short-circuits; 5) superstrates and 6) combinations of them [1].
