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[Author] Chika SUGIMOTO(4hit)

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  • Multiplexing and Error Control Scheme for Body Area Network Employing IEEE 802.15.6

    Kento TAKABAYASHI  Hirokazu TANAKA  Chika SUGIMOTO  Ryuji KOHNO  

     
    PAPER

      Vol:
    E97-B No:3
      Page(s):
    564-570

    This paper proposes and investigates a multiplexing and error control scheme for Body Area Network (BAN). In February 2012, an international standard of WBAN, IEEE802.15.6, was published and it supports error control schemes. This standard also defines seven different QoS modes however, how to utilize them is not clearly specified. In this paper, an optimization method of the QoS is proposed. In order to utilize the QoS parameters, a multiplexing scheme is introduced. Then, the Hybrid ARQ in IEEE 802.15.6 is modified to employ decomposable codes and Weldon's ARQ protocol for more associations with channel conditions and required QoS. The proposed scheme has higher flexibility for optimizing the QoS parameters according to the required QoS.

  • Interference Cancellation for Intra and Inter UWB Systems Using Modified Hermite Polynomials Based Orthogonal Matched Filter

    Takumi KOBAYASHI  Chika SUGIMOTO  Ryuji KOHNO  

     
    PAPER

      Vol:
    E99-B No:3
      Page(s):
    569-577

    Ultra-wideband (UWB) communications is used for medical information communication technology (MICT) as a dependable and safe communication technology in recent years. On the other hand, there are existing various UWB systems that are not used for MICT. Generally, these UWB systems use almost the same frequency band. Therefore, they interfere to each other in general transmission channel environment. In our previous work, a novel UWB pulse shape modulation using modified Hermite pulse is proposed as a multiple user access scheme. In this paper, we propose a mitigation method for inter-user interference and inter-system interference using combination of orthogonal pulse shape modulation and orthogonal matched filter (OMF) detector. The purposes of our system are to detect all signals of users in the same UWB system and to reduce the unknown interference from other UWB systems at the same time. This paper provides performance evaluation results based on both of analytical and numerical evaluation. Simulation results show that the proposed system can detect the signals that were transmitted from the same UWB system using orthogonal pulse set, while the proposed system can reduce the interference from unknown UWB systems at the same time. The theoretical analysis is expected that noise tolerance of our proposal will be deteriorated in the additive Gaussian noise channel in comparison with the conventional matched filter. It is confirmed that the numerical evaluation illustrates such noise tolerance equivalent to the theoretical analysis result.

  • Nonlinear Acoustic Echo Suppression Based on Spectrum Selection Using the Amount of Linear Echo Cancellation

    Takashi SUDO  Hirokazu TANAKA  Chika SUGIMOTO  Ryuji KOHNO  

     
    PAPER

      Vol:
    E97-A No:11
      Page(s):
    2139-2146

    Hands-free communications between cellular phones must be robust enough to withstand echo-path variation, and highly nonlinear echoes must be suppressed at low cost, when acoustic echo cancellation or suppression is applied to them. This paper proposes a spectrum-selective nonlinear echo suppression (SS-ES) approach as a solution to these issues. SS-ES is characterized by the selection of either a spectrum of the residual signal from an adaptive filter or a spectrum of the sending input signal depending on the amount of linear echo cancellation in an adaptive filter. Compared to conventional methods, the objective evaluation results of the SS-ES approach show an improvement of approximately 0.8-2.2dB, 0.23-2.39dB, and 0.26-0.50 in average echo return loss enhancement (ERLE), average root-mean-square log-spectral distortion (RMS-LSD), and the perceptual evaluation of speech quality (PESQ) value, respectively, under echo-path variation and double-talk conditions.

  • Medical Healthcare Network Platform and Big Data Analysis Based on Integrated ICT and Data Science with Regulatory Science Open Access

    Ryuji KOHNO  Takumi KOBAYASHI  Chika SUGIMOTO  Yukihiro KINJO  Matti HÄMÄLÄINEN  Jari IINATTI  

     
    INVITED PAPER

      Pubricized:
    2018/12/19
      Vol:
    E102-B No:6
      Page(s):
    1078-1087

    This paper provides perspectives for future medical healthcare social services and businesses that integrate advanced information and communication technology (ICT) and data science. First, we propose a universal medical healthcare platform that consists of wireless body area network (BAN), cloud network and edge computer, big data mining server and repository with machine learning. Technical aspects of the platform are discussed, including the requirements of reliability, safety and security, i.e., so-called dependability. In addition, novel technologies for satisfying the requirements are introduced. Then primary uses of the platform for personalized medicine and regulatory compliance, and its secondary uses for commercial business and sustainable operation are discussed. We are aiming at operate the universal medical healthcare platform, which is based on the principle of regulatory science, regionally and globally. In this paper, trials carried out in Kanagawa, Japan and Oulu, Finland will be revealed to illustrate a future medical healthcare social infrastructure by expanding it to Asia-Pacific, Europe and the rest of the world. We are representing the activities of Kanagawa medical device regulatory science center and a joint proposal on security in the dependable medical healthcare platform. Novel schemes of ubiquitous rehabilitation based on analyses of the training effect by remote monitoring of activities and machine learning of patient's electrocardiography (ECG) with a neural network are proposed and briefly investigated.