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In this paper, a planar small size coplanar waveguide (CPW)-fed wideband antenna is presented for wearable applications. The antenna operates for 1395–1400 MHz and 1427–1432 MHz wireless medical telemetry service (WMTS) bands. The center frequencies of the two bands are 1397.5 MHz and 1429.5 MHz. The antenna occupies a volume of 48 mm × 52 mm × 0.8 mm. The simulated and measured reflection coefficients, radiation patterns and gain are calculated and found to be in good agreement, validating the proposed antenna design. The simulation results for SAR and bending are also presented to demonstrate that the proposed antenna operates within the approved limits and can be fabricated on a flexible substrate. [ABSTRACT FROM AUTHOR]

In this article a modified hybridized fractal geometry i.e., fractal antenna is proposed for Multiple Input Multiple Output (MIMO) applications. These geometries are based on Minkowski curves and Koch curves located around the boundaries of the microstrip patch of rectangular-shaped patch. The hybridized model for fractal geometry is designed and analyzed on an FR4 substrate having a thickness of 1.47 mm for the Industrial, Scientific, and Medical (ISM) frequency band. But due to the proposed fractal geometry, it resonates at three bands (2.45 GHz, 3.67 GHz, and 5.88 GHz) and it is covering the ISM band from 2.42 GHz to 2.48 GHz with a VSWR value is 1.48. Further, a 2 × 2 antenna for MIMO application is proposed by considering identical antenna elements placed in parallel on the same substrate. MIMO antenna resonates at three frequencies as same as single antenna elements and covering the same operating bands. The two elements of MIMO confguration are simulated for various sets of distance values, and optimized distance is obtained 18 mm at which a proposed antenna provides low mutual coupling value, low Envelope Correlation Coefficient (ECC), and high diversity and peak gain. The calculated values of ECC and diversity gain are 0.0002 and 10 dB, respectively which satisfy the criteria of MIMO application. The design has been experimentally validated and an appropriate similarity of experimental and simulated results is achieved. [ABSTRACT FROM AUTHOR]

This paper is in continuation of our previous published work, in which effect of user's body is studied for quad band diversity antenna. The antenna has been successfully designed and studied in the free space. In this study, three kinds of user effects on previously proposed antenna are considered, namely, 'Specific Anthropomorphic Mannequin (SAM) head and PDA hand (Talk mode)', 'Personal Digital Assistants (PDA) hand (Data mode)', and 'Dual hands (Read mode)'. There are two different positions of the quad band antenna over mobile circuit board is considered i.e., antenna at top position and bottom position of mobile circuit board. In the user proximity, the optimal location of antenna over circuit board is chosen for real application based on the antenna performance parameters i.e. S-parameters, diversity performances, and radiation performances. The specific absorption rate (SAR) for American standard (1.6 W/kg average over 1 g tissues) and European standard (2 W/kg average over 10 g tissues) is calculated for the top and bottom position of the MIMO antenna elements and it is found that the values of SAR is well below the standard limit of FCC as well as European standard. Based on the study, it is found that antenna at top position of mobile circuit board shows overall better performance in the presence of user's body. [ABSTRACT FROM AUTHOR]