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Low profile antenna in communication is a new methodology. Fractal geometry is a methodology through which size reduction is achieved. A Self-similar fractal antenna using multicantor technique is proposed and experimentally studied. Space-filling cantors and self-similarity properties of fractal geometry have been adopted in the proposed antenna to miniaturize the size of antenna. The antenna is designed in such a way to operate at MICS band (Medical Implant communication Service) for wireless telemedicine application. The prototype antenna exhibits wideband characteristics and provides a good agreement of return loss (S11). Experimental return loss has been compared with that which is obtained using method of moments. The objective of using self-similar concept in antenna makes it flexible in terms of controlling the resonance and bandwidth. In this paper, the Self-similar property of fractal geometry is examined by maintaining return loss (S11) more than –30 dB approximately in all the iterations (n) and the prototype antenna has return loss greater than –10 dB and exhibits wideband characteristics

This paper presents a novel design of printed hybrid fractal tree (PHFT) antenna using bacterial forging optimization (BFO) in conjunction with curve fitting technique. The antenna geometry is based on the hybrid structure obtained by integrating meander line geometry with fractal tree, whose geometrical descriptors are determined by means of BFO. The fractal shape allows the new hybrid antenna to be effectively reduced in size without significantly impairing performance. Representative results of optimized antenna are reported in order to access the effectiveness of the developed approach for reliable implementation in wireless telemedicine applications. Moreover, useful guidelines on the effects of finite ground plane size on antenna characteristics have been adequately analyzed.

In this article, an attempt is made to provide two level securities for medical images using watermarking and encryption. Watermarking provides security and encryption, authenticates medical image and provides integrity. Watermarking is performed by using a new nontensor product wavelet filter banks, which have the ability to reveal singularities in different directions. Natural image is taken as the original image and the medical image is taken as a watermark image. The medical image is embedded into the LH sub band of the natural image. The encryption is performed by RSA, AES, and RC4 algorithms. A qualitative comparative analysis of the proposed algorithm is done for different encryption methods. The proposed algorithm has the ability to withstand different attacks like noise, rotation, contrast, and brightness attacks. Performance analysis is made by calculating PSNR, SSIM, NC, and CV.

A compact multiband fractal antenna which is a new criterion in communication is proposed. The optimized prototype measures 35 mm×31 mm×1.6 mm. The proposed antenna covers WLAN IEEE 802.11b, 802.15, PCS, GSM lower and higher bands, DCS, IMT, UMTS, Wi-Fi, and WLAN wireless applications. The proposed antenna exhibits multiband characteristics with anS11of−30.69 dB at design frequency and it is found that~70% of theS11graph below−10 dB reference is achieved. ExperimentalS11has been compared with the one which is obtained using method of moments. The aim of implementing self-affine fractal concept in antenna design makes it flexible in controlling the resonance and bandwidth. This paper investigates self-affine fractal geometry to miniaturize and to resonate multiband frequencies. The prototype model with a good agreement ofS11is reported.