*3.1.3 Lengthening of the current flow path of radiator*

Gain reduction can be possible by keeping a high relative dielectric constant of materials and planar inverted F antenna (PIFA) type antenna with structures like meandered, spiral, slot, etc. The longer the path of the radiator, the resonant frequency can be shifted towards a lower resonant frequency. Hence, size can be reduced. In [47] the antenna is square shape (case a), on which the current path is
