Design and analysis of wearable antennas for use in wireless biomedical telemetry systems

This thesis presents the design of a fractal printed circuit antenna construction for portable applications. A modified Hilbert patch was printed on a flexible polyamide substrate for the proposed antenna. An open loop with a defective electromagnetic band gap (EBG) surrounds the antenna. Experimental findings are compared to simulated results from a commercial software package based on Computer Simulation Technology Microwave Studio for the proposed antenna (CST MW). The experimental and simulated findings are found to be quite similar. The suggested antenna design is determined to be compatible with the frequency ranges of UHF and ISM portable systems. The antenna shows two bandwidths from 0.8GHz to 1GHz and from 2.3GHz to 2.6GHz with average gain of around 3.1dBi and 7dBi, respectively. The antenna performances are conducted based on analytical and numerical simulations. The fabricated prototype performances have been measured experimentally to show excellent agreement with the simulated results. Finally, it is found that the proposed antenna frequency resonance and bandwidth are insignificantly affected when mounted in close to the human body; therefore, it would be excellent candidate to be in use with biomedical applications. The proposed antenna shows several resonances around the Body Area Networks (BAN) and ISM frequency bands. The proposed antenna shows a suitable gain for short and medium wireless communication systems about 1dBi, 1.24dBi, 1.48dBi, 2.05dBi, and 4.11dBi at 403MHz, 433MH, 611Mz, 912MHz, and 2.45GHz, respectively. The antenna is printed using silver nanoparticle ink on a polymer substrate. The antenna size is reduced to 20×10mm2 to suit the different miniaturized wireless biomedical devices. The fabricated prototype has been tested experimentally on the human body. The main novelty with this design is suppressing the surface wave from the patch edges, allowing it to significantly reduce the back radiation toward the human body when used enclosed to it.The proposed antenna is located on the human head to determine the specific absorption rate (SAR). It is found in all cases, the proposed antenna shows low SAR effects on the human body.