8 documents found, page 1 of 1
Slot antenna design for a wirelessly powered implantable microcooler for neuron...
Dinis, H.; Fernandes, J.; Mendes, P. M.Implantable medical devices are becoming smaller by the day, with more efficient electronics and smaller power demands. Nevertheless, there are some applications in which power demands are inherently high, and solutions must be found in order to keep the devices as small as possible. In this paper, we propose an antenna to be used in wirelessly powering a focal brain cooling implant based on a Peltier device. T...
Thermal modeling of an implantable brain focal cooling device
Dinis, H.; Fernandes, J.; Silva, Vinicius Corrêa Alves; Colmiais, Ivo Henrique Baltazar; Mendes, P. M.An implantable focal cooling device based on a Peltier is proposed in this paper. The building blocks of this device, namely its battery management, wireless power transfer, communication, and power management modules are presented and discussed. Simulated and experimental data in a deionized water phantom at 37 degrees C validate the use of the Peltier as a focal cooling device, and simulations in rat brain fu...
A multiantenna approach to maximize wireless power transfered to implantable de...
Dinis, H.; Colmiais, Ivo Henrique Baltazar; Mendes, P. M.Power delivery from an external source to implanted devices through wireless links is hindered by SAR regulations, which limit the amount of power radiated by an external source that reaches an implant. In order to increase the power delivered to the implant, we studied a solution with two transmitters and compared results with the common single transmitter link. HFSS and COMSOL have been used to show that a po...
Performance assessment of wireless power transfer links for implantable microsy...
Dinis, H.; Mendes, P. M.Wireless power transfer is a hot topic due to the growth of implanted device solutions which, as they get smaller and smarter, demand new solutions to power them up. These solutions need to keep the power level, namely SAR (specific absorption ratio) below a determined safety standard and to allow the device to be as small as possible. Current fabrication techniques allow the creation of ultra-small 3D antennas...
Characterization of chip-size electrically-small antennas for smart wireless bi...
Dinis, H.; Anacleto, P.; Fernandes, J.; Mendes, P. M.The new requirements for smarter and smaller biomedical microsystems demand for new integration technologies, including antenna integration. This can be solved with the use of microfabrication technologies, allowing the fabrication of chip-size antennas that may be placed on top of silicon wafers. However, due to their ultra-small physical dimensions and special operating conditions (e.g., covered with body tis...
On-chip, efficient and small antenna array for millimeter-wave applications
Dinis, H.; Zamith, M.; Fernandes, J.; Magalhaes, J.; Mendes, P. M.The high path losses experienced by wireless applications at millimeter wavelengths may be mitigated using high gain antennas. The intrinsic small wavelengths makes very attractive to develop solutions with on-chip integrated antennas. However, due to silicon high losses, on-chip antenna elements on RFCMOS technology have reduced efficiency. This paper proposes a solution to obtain an on-chip integrated antenna...
Performance assessment of an RFID system for automatic surgical sponge detectio...
Dinis, H.; Zamith, M.; Mendes, P. M.A retained surgical instrument is a frequent incident in medical surgery rooms all around the world, despite being considered an avoidable mistake. Hence, an automatic detection solution of the retained surgical instrument is desirable. In this paper, the use of millimeter waves at the 60 GHz band for surgical material RFID purposes is evaluated. An experimental procedure to assess the suitability of this frequ...
Aspectos da vida sexual de doentes com espinha bífida em Portugal
Conceição, Paulo; Dinis, H.; Temido, P.; Patrício, A.; Conceição, M.; Martins, L.; Fonseca Santos, M.; Sobral, F.; Quaresma, L.; Pereira, N. MonteiroO tratamento multidisciplinar da espinha bífida resultou num considerável aumento do número de doentes a atingirem a idade adulta. A vida sexual de um doente com espinha bífida está afectada não só pelas limitações físicas inerentes à doença, mas também pelos impactos psicológico e social desta doença. Trata-se de um tema de proporções pouco conhecidas, particularmente na população portuguesa de doentes com esp...