Procédé de correction auditive utilisant un modèle paramétrique du signal de parole

Cet article présente un nouveau procédé de correction auditive utilisant un modèle paramétrique du signal de parole. Ce procédé permet, en plus des opérations classiques de compression et d'amplification, d'effectuer des transformations élaborées (modification du rythme temporel, modification de l'enveloppe spectrale, etc.) tout en conservant la structure naturelle du signal de parole. Les premiers résultats d'une série de tests cliniques montrent que ce procédé est bien accueilli par les personnes atteintes de surdités intermédiaires (moyennes ou sévères) et pour lesquelles il n'existe pas véritablement de traitement prothétique adapté

Ultra-Low-Profile Continuous Transverse Stub Array for SatCom Applications

International audienceModern K-/Ka-band satellite communications have become increasingly demanding in recent years with regard to the performance of the terminal antenna used in the link. These terminals should be high gain and broadband, as well as guarantee polarization diversity over a large field of view. A low profile is also highly desired to integrate the antenna system into a variety of moving platforms, such as aircraft and trains. An ultra-low-profile continuous transverse stub array is proposed here to tackle these challenges. The antenna array is realized in printed circuit board technology by adopting a contactless transition between the stacked-up layers without resorting to blind or buried vias. The proposed antenna is wideband (impedance matched within the 19-31 GHz band, i.e., similar to 50%) and provides multibeam radiation for polar angles as far as +/- 22.5 degrees. The peak value of the gain is 19.7 dBi, and the maximum radiation efficiency equals 50%. Furthermore, the antenna array is combined with a dual-band polarization converter. The latter provides orthogonal circular polarization (CP) in two non-adjacent bands. The overall antenna system performs right- and left-hand CPs within the SatCom downlink and uplink in the K-/Ka-band, respectively. For each polarization, the axial ratio is below 3 dB over 9.47% and 4.42% fractional bandwidths, respectively