Browsing NTNU Open by Author "Pourafzal, Alireza"

Now showing items 1-5 of 5

    • Acoustic-and Radio-Frequency-Based Human Activity Recognition 

      Mohtadifar, Masoud; Cheffena, Michael; Pourafzal, Alireza (Peer reviewed; Journal article, 2022)
      In this work, a hybrid radio frequency (RF)- and acoustic-based activity recognition system was developed to demonstrate the advantage of combining two non-invasive sensors in Human Activity Recognition (HAR) systems and ...

    • Do you have any privacy? Human activity privacy leak from wearable devices 

      Tønnesen, Rolf Martin (Master thesis, 2023)
      Dette prosjektet viser gjennom et simulert scenario hvordan personlig informasjon kan lekkes til en utenforstående person med uhederlige hensikter fra helse og aktivitetssensorer. Metoden som brukes i prosjektet er å ...

    • Energy-Efficient and Low-Cost Wireless Sensor System Designs Based on Spectral Lines Analysis 

      Pourafzal, Alireza (Doctoral theses at NTNU;2023:441, Doctoral thesis, 2023)
      This thesis presents a comprehensive investigation into the development of energy-efficient, low-cost wireless sensor systems in the context of the Internet of Things landscape. We examined two sensor technologies, microwave ...

    • Low complexity subspace approach for unbiased frequency estimation of a complex single-tone 

      Pourafzal, Alireza; Škrabánek, Pavel; Cheffena, Michael; Yildirim, Sule; Roi-Taravella, Thomas (Journal article, 2024)
      We propose a single-tone frequency estimator of a one-dimensional complex signal in complex white Gaussian noise. The estimator is based on the subspace approach and the unitary transformation. Due to its low space and ...

    • A Low-cost and Accurate Microwave Sensor System for Permittivity Characterization 

      Pourafzal, Alireza; Roi-Taravella, Thomas; Cheffena, Michael; Yildirim Yayilgan, Sule (Peer reviewed; Journal article, 2022)
      A novel low-cost microwave sensor system is proposed for accurate sensing of the real relative permittivity of materials under test (MUT). The proposed solution eliminates the need for using advanced measurement devices ...