Metamaterial-inspired electrically small antennas (ESA) were proposed in  and their electrical monopole versions were further developed in  and . Measurements of the metamaterial-engineered Z antenna introduced in  have been reported  and show great consistency between the measurement and the HFSS simulation results. Those results continue to demonstrate that the metamaterial-engineered ESA design methodology is a viable approach. In the Z antenna, the Z structure is a near-field, self-resonant, parasitic (NFRP) element whose resonance frequency is mainly determined by its lumped element inductor and its capacitive top strip. The NFRP Z structure resonance frequency approximately determines the resonance frequency of the Z antenna, i.e, reactance matching is achieved with the Z structure. Resistance matching to, e.g., a 50Ω source is obtained from the coupling between the NFRP Z element and the directly driven element, its coax-fed monopole.