12 research outputs found
A Novel Wideband and Multi-band Implantable Antenna Design for Biomedical Telemetry
International audienceIn this work, a novel multi-tracks wideband and multi-band miniaturized antenna design for implanted medical devices biomedical telemetry is proposed. This antenna entirely covers seven frequency bands which are the bands (401â406) MHz of the Medical Device Radiocommunications Service (MedRadio), the three bands (433.1â434.8), (868.0â868.6), and (902.8â928.0) MHz of the Industrial, Scientific, and Medical (ISM), and the three bands (608â614) MHz, and (1.395â1.400) and (1.427â1.432) GHz of the Wireless Medical Telemetry Service (WMTS). The antenna possesses a compact full size of (19.5 Ă 12.9 Ă 0.456) mm3. The antenna miniaturization and impedance bandwidth enhancement are achieved using two techniques: the patch slotting and insertion of open-end slots in the ground plane, respectively. Prototype of proposed antenna with multi-tracks has been fabricated and tested in free space. The comparison between the simulated and measured reflection coefficient has been done and found in good agreement with each other. Furthermore, simulations of the proposed antenna implanted in the underneath the scalp in a realistic human model shows a wideband operation from 0.19 to 0.94 GHz, and from 1.38 to 1.54 GHz corresponding to return loss (S11 †â10 dB). Link budget calculation is performed to specify the range of telemetry considering both Specific Absorption Rate (SAR) restrictions and effective isotropic radiated power (EIRP) limitations. The designed implantable antenna with full ground plane presents an appropriate reflection coefficient for muscle implantation. Furthermore, the designed implanted muscle antenna may be also suitable for skin implantation
IMPROVING THE PERFORMANCES OF A HIGH TC SUPERCONDUCTING CIRCULAR MICROSTRIP ANTENNA WITH MULTILAYERED CONFIGURATION AND ANISO TROPIC DIELECTRICS
Miniaturization of a PIFA Antenna for Biomedical Applications Using Artificial Neural Networks
International audienceThis work deals with the optimization of an inverted F dual-band implantable antenna operating in Medical Device Radiocommunications Service (MedRadio, 401-406 MHz) and Industrial Scientific Medical (ISM, 902-928 MHz) applications bands. Artificial neural networks (ANNs) are implemented to minimize the size of the initial design. The ANN's output with the physical and dielectric parameters of antenna as inputs is tested using COMSOL MultiphysicsÂź. The obtained results regarding the return loss S11, resonant frequency and bandwidth of the antenna are presented and discussed. Indeed, the size of the antenna is reduced by 21.48% with respect to the initial size while preserving its initial good performance in both frequency bands
Efficient Parallelization of Electromagnetic Field Computations on a Beowulf Cluster
International audienc
Compact coplanar waveguideâfed reconfigurable fractal antenna for switchable multiband systems
In this study, a coplanar waveguide-fed reconfigurable antenna using crescent-shaped fractal geometry is presented. The frequency reconfigurable approach is obtained using radio-frequency positive intrinsic negative diodes, resistor, and inductors. The proposed approach has successfully allowed reconfigurable switching up to eight frequency bands between 1.46 and 6.15 GHz. Good results have been obtained in terms of stable and omnidirectional radiation patterns. The realised gains of the antenna system, in these frequency bands, vary from 0.52 to 5.67 dBi. The designed antenna has the advantages of a multiband structure and compact size over the previously reported structures. The proposed antenna is suitable for future wireless application systems
Experimental Study on the Use of Microencapsulated Phase Change Material in Walls and Roofs for Energy Savings
International audienc
A compact CPW-Fed hexagonal antenna with a new fractal shaped slot for UWB communications
International audienceIn the present paper, a simple and compact a coplanar waveguide (CPW)-Fed hexagonal antenna has been presented. The proposed antenna is composed of a new fractal shaped slot with a hexagonal patch fed. The total size of the presented antenna is 14.5Ă16.5 mm 2 , which is designed on Rogers RO4350B substrate and having dielectric constant Δ r =3.66, a thickness of h=1.524 and loss tangent of 0.004. The impedance bandwidth, defined by -10 dB reflection coefficient. Hence, the simulated results get a proper agreement with an impedance bandwidth of 2.98 GHz to 11.4 GHz. The investigated antenna is suitable for UWB applications. The design validation of the fractal antenna has been achieved by using CST Microwave studio
Design of reconfigurable fractal antenna using pin diode switch for wireless applications
International audienceIn this article, a frequency reconfigurable fractal patch antenna using pin diodes is proposed and studied. The antenna structure has been designed on FR-4 low-cost substrate material of relative permittivity Δr = 4.4, with a compact volume of 30Ă30Ă0.8 mm3. The bandwidth and resonance frequency of the antenna design will be increased when we exploit the fractal iteration on the patch antenna. This antenna covers some service bands such as: WiMAX, m-WiMAX, WLAN, C-band and X band applications. The simulation of the proposed antenna is carried out using CST microwave studio. The radiation pattern and S parameter are further presented and discussed