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This article presents the design of a polydimethylsiloxane based flexible antenna for body worn applications. In order to reduce the specific absorption rate (SAR) metasurface (MS) based unit cell is proposed. Copper foil of thickness 3 mil considered for conducting layers. The proposed antenna is designed with leaf structure and covers the WLAN ISM band 2.4 GHz without metasurface (NMS) and with metasurface (WMS) unit cell. The MS unit cell at the backside of the antenna does not cover the entire antenna but only a portion of it where the backward energy is highly concentrated. This yields better result in reducing the SAR with a very compact sized MS unit cell. This MS structure improves the gain of an antenna and also reduces the SAR, by directing the radiating energy in opposite direction from the human user. The proposed antenna NMS has a simulated SAR value of 2.53 W/kg at 2.4 GHz over volume of 1 g of tissue, whereas WMS it is reduced to 1.53 W/kg. The comparative analysis of the proposed antenna presented with the help of performance matrices like reflection coefficient, SAR, gain, and radiation patterns.

In this article, we propose an ultra wide band (UWB) bandpass filter with dual notch characteristics. The proposed filter is designed based on composite right/left handed (CRLH) transmission lines. The filter is having a compact size of 2.4 mm × 8.78 mm and printed on FR4 material with relative permittivity 4.4 with thickness 1.6 mm. The filter is constructed by series of strip lines, which forms interdigital capacitance and shunt inductors allowing both low and high frequencies of the UWB to pass. The selectivity in lower and higher parts of the UWB is achieved by the slots etched from the ground plane. The dual band notch is obtained at 4 GHz and 7 GHz using the L‐shaped strip lines on both sides of the filter. The comparative analysis of the proposed UWB band pass filter without and with notch characteristics is presented with the help of the S11 and S21 curves.

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