Volume 8 Number 2 September 2025

    
New Efficient PAPR Reduction Schemes in LTE OFDM Systems

Saleem Nokaiee, Mohammed M. Alkhawlani

https://doi.org/10.6025/stj/2019/8/2/39-53

Abstract Orthogonal frequency division multiplexing (OFDM) is a prominent, new multicarrier modulation technology used with most 4G wireless communication systems. It was configured with MIMO to transmit very high rates of digital information with enhanced performance and speed. However, OFDM faced high peak to average power ratio (PAPR) issue at the transmitter. In this paper, a new companding method called advanced... Read More


An Elderly - Care System Based on Sound Analysis

Martin Frešer, Igor Košir, Violeta Mirchevska, Mitja Luštrek

https://doi.org/10.6025/stj/2019/8/2/54-59

Abstract This paper proposes an elderly-care system, which uses a single sensing device installed in the user’s home, primarily based on a microphone. We present preliminary results on human activity recognition from sound data. The recognition is based on 19 types of sound features, such as spectral centroid, zero crossings, Melfrequency cepstrum coefficients (MFCC) and linear predictive coding (LPC). We distinguished... Read More


Mining Telemonitoring Data from Congestive-heart-failure Patients

Mitja Luštrek, Maja Somrak

https://doi.org/10.6025/stj/2019/8/2/60-66

Abstract The Chiron project carried out an observational study in which congestive-heart-failure patients were telemonitored in two countries. Data from 1,068 recording days of 25 patients were gathered, consisting of 15 dynamic parameters (measured daily or continuously) and 49 static parameters (measured once or a few times during the study). The features derived from these parameters were mined for their association... Read More