Design and performance investigation of metamaterial based antennas with fr 4 and leather substrates

Abstract

The development of technology in wireless communication poses many new challenges for antenna design. Over the last decade many techniques were proposed to improve the performance of the antenna. newlineIn the recent years metamaterial concept has become very interesting among the researchers because of their advantages such as miniaturization, gain enhancement, bandwidth enhancement, directivity enhancement, improved radiation patterns and so on. In this research work metamaterial-based antennas are developed to provide high gain, good radiation characteristics and low Specific Absorption Rate (SAR). This metamaterial-based antennas exhibit negative permeability and permittivity characteristics, which are extracted from S-parameters using Nicholson-Ross-Weir (NRW) method. An inverted H-shaped metamaterial superstrate antenna, metamaterial-based split ring resonator (SRR) antenna, dual band metamaterial antenna using leather substrate and triple band partially ground plane metamaterial antenna are designed, fabricated and validated experimentally with simulated results. newlineThe inverted H-shaped metamaterial superstrate antenna is designed with a dimension of 100x80 mm2. The superstrate is composed of 80 unit cells and it is suspended over the rectangular patch antenna with a distance of 5 mm. This antenna is fabricated with low priced FR-4 substrate and the operating frequency of this antenna is 1.8 GHz (L band). It provides 4.1 dB gain enhancement. newlineThe metamaterial-based split ring resonator (SRR) antenna is designed with FR-4 substrate and its dimension is 56x56 mm2. Three superstrate layer is constructed and is composed of 75 unit cells. It is kept over the slotted square patch with a distance of 10 mm. One superstrate is framed with 25 unit cells. This antenna is kept nearest to the head phantom model at a constant distance to scan and detect the tumour. newline