In today's world of miniaturization sensitivity of satellite communication system depends on isolation between transmitting and receiving Microstrip patch antennas which shares common ground plane. Coupling between transmitting and receiving antenna degrades overall system performance. It had been observed that When two patches were separated by the distance equal or greater than ?/10, we can formulate antenna parameters. But the world of miniaturization does demand distance between two patches has to be minimum. Manuscript suggests technique to improve isolation between patches which are separated by distance which is almost ?/24. Such less physical separation between them causes measurable amount of coupling between two patch antennas. The manuscript suggest the technique to improve isolation using Thin Wire (TW) Metamaterial structure which exhibits negative permeability. . Design and characterization of the Metamaterial are presented and it is shown that within a certain frequency band, the material behaves as anisotropic electric plasma, suppressing the mutual coupling. Height of TW is same as substrate height. Array of TW which is inserted between two patches reduces coupling due to surface wave. Also TW had been inserted at the radiating edge of one of the patch where near field just starts which helps to reduce coupling due to radiation in near field. Simulation results using HFSS shows that insertion of TW Metamaterial structure enhances isolation almost by 12 dB without affecting the antenna parameters such as impedance bandwidth gain, directivity and radiation pattern. The only limitation about the same is that band of frequencies over which TW exhibits the negative permittivity is less which can be overcome by placing them at both radiating edges of both patches.

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Isolation Microstrip Antenna Metamaterial.