Browsing by Subject "Oceanography"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    A new signaling scheme for Underwater Acoustic communications
    (IEEE, 2013) Elmoslimany, A.; Zhou, M.; Duman, Tolga M.; Papandreou-Suppappola, A.
    Underwater Acoustic (UWA) communications has attracted a lot of interest in recent years motivated by a wide range of applications. Different signaling solutions have been developed to date including non-coherent communications, phase coherent systems, multi-input multi-output (MIMO) solutions and multi-carrier based approaches. In this paper, we develop a novel UWA communications paradigm using biomimetic signals. In our scheme, digital information is mapped to the parameters of a class of biomimetic signal set and at the receiver an estimator to obtain the parameter values is utilized. To facilitate this, we develop analytical signal models with nonlinear instantaneous frequencies matching mammalian sound signatures in the time-frequency plane. We provide suitable receiver structures, and present decoding results using data recorded during the Kauai Acomms MURI 2011 (KAM11) UWA communications experiment. © 2013 MTS.
  • Thumbnail Image
    ItemOpen Access
    An underwater acoustic communications scheme with inherent scale diversity for multiple users
    (IEEE, 2013) Zhou, M.; Zhang J.J.; Papandreou-Suppappola, A.; Duman, Tolga M.
    Wideband underwater acoustic communication channels can cause undesirable multipath and Doppler scaling distortions to propagating acoustic signals. In this paper, we propose to exploit a time-scale canonical representation for wideband time-varying channels to achieve joint multipath-scale diversity. We design a signaling scheme with hyperbolic time-frequency signatures that is matched to the underwater acoustic environment to achieve scale diversity. The signaling scheme, combined with code-division multiple-access, is extended to multiple user transmission to improve multiuser detection performance, as demonstrated with simulations. © 2013 MTS.