We report and experimentally demonstrate the generation of impulse radio ultrawideband (UWB) pulses using a photonic chip frequency discriminator. The discriminator consists of three add-drop optical ring resonators (ORRs) which are fully programmable using thermo-optical tuning. This discriminator chip in combination with a phase modulator forms a temporal differentiator where phase modulation is converted to intensity modulation (PM-IM conversion). By means of tailoring the discriminator response using either the individual or the cascade of drop and through responses of the ORRs, first-order or second-order temporal differentiations are obtained. Using this principle, the generation of UWB monocycle, doublet and modified doublet pulses are demonstrated. The use of this CMOS-compatible discriminator is promising for the realization of a compact and low cost UWB transmitter.

International audienceIt is now established that optical wireless communications (OWC) technology is a promising alternative or a complement to radio-frequencies for indoor transmissions. Considering that using OWC permits the reduction of electromagnetic pollution in human environment, this technology can be also a good candidate for wireless body area networks (WBANs) in particular for medical applications such as health monitoring. In this paper, we investigate the use of on-body OWC for mobile medical WBAN. Based on transmission scheme exploiting diffuse optical reflections over the patient environment, we investigate a star BAN topology using spreading codes for multiple access. We have developed a theoretical analysis to determine the performance of such network considering that the patient is moving in the room. The achievable quality of service for a typical health monitoring application is reported and discussed regarding the performance required by medical applications

No abstract

International audienceUsing wireless optical communication (WOC) to establish on-body links constitutes a promising solution to address radiofrequency interference issues in body area network (BAN) especially concerning medical applications. Actually, this permits decreasing electromagnetic perturbations in the patient body environment. To evaluate WOC performance for BAN scenario, the authors investigate on-body communication between a BAN node and the central unit placed on the patient which is supposed to be moving in a room. Considering a diffuse optical transmission scheme based on optical reflections over the environment, the authors propose an adapted, fast and simple method to determine the performance taking into account the presence of obstacles in the room. Thanks to this method, the authors evaluate the WOC outage probability assuming uniform node mobility on the patient body and patient mobility in the environment. The results permit discussing the WOC robustness according to the optical reflection properties of the blocking elements and show the WOC potentialities for mobile medical BAN scenario