Body worn antennas generally face the problem of isolation when operated in close proximity to human body. Use of magneto-dielectric material as substrate for antenna makes the system compact and reduces the influence of body on performance of antenna. In addition, miniaturization of antenna size also takes place. 7 wt.% of nano-sized Ni 0.5 Zn 0.5 Fe 2 O 4 is dispersed as magnetic filler in flexible linear low density polyethylene matrix. Beyond 7 wt.%, the sample stiffens and loses flexibility because of percolation limit of the polymer. Verification of the composite as a potential substrate for a body worn antenna is carried out by fabricating a coplanar waveguide fed simple rectangular monopole antenna, using transmission line model at 6 GHz. Antenna performance is studied by wearing the patch on human wrist. S 11 of −21.78 dB at 5.32 GHz and −10 dB bandwidth of 49.62% is observed. For comparison, an antenna at the same resonant frequency is developed on linear low density polyethylene with magnetic inclusions. The antenna on magneto-dielectric substrate shows better performance than dielectric substrate. The magnetic and dielectric properties of the Nickel Zinc Ferrite-linear low density polyethylene composite magneto-dielectric substrate reduces the influence of the human body which makes the antenna system compact and robust as additional techniques are not required for shielding of human body influence on antenna performance.

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Slots are incorporated in ground plane of a simple rectangular patch antenna designed in C-band on FR-4 substrate with dielectric constant e r 5 4.3 and height, h 5 1.5 mm. The presence of slots shows multi frequency characteristics with enhanced bandwidth and directivity as compared to simple patch antenna without modified ground plane. The S 11 parameter, impedance bandwidth, and radiation characteristics are studied for the antenna with and without modified ground plane. Two slots geometry shows three resonant frequencies with S 11 < 217 dB and enhancement in 210 dB bandwidth of 11.74% at 5.96 GHz. In three slots geometry, two resonant frequencies are observed with S 11 < 220 dB and enhancement in 210 dB bandwidth of 13.05% at 5.44 GHz.