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All Journal International Journal of Electrical and Computer Engineering Jurnal Elektronika dan Telekomunikasi
Galih Nugraha Nurkahfi
National Research and Innovation Agency
Computer Science & IT Electrical & Electronics Engineering Engineering

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SIMONIC: IoT Based Quarantine Monitoring System for Covid-19 Vita Awalia Mardiana; Mochamad Mardi Martadinata; Galih Nugraha Nurkahfi; Arumjeni Mitayani; Dayat Kurniawan; Nasrullah Armi; Budi Prawara; Sudirja Sudirja; Andria Arisal; Rendra Dwi Firmansyah; Andri Fachrur Rozie; Sulaksono Priyo; Sopyan Setiana; Asih Setiarini
Jurnal Elektronika dan Telekomunikasi Vol 21, No 2 (2021)
Publisher : LIPI Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/jet.v21.112-121

Abstract

COVID-19, which has become a global pandemic since March 2020, has tremendously affected human life globally. The negative impact of COVID-19 affects societies in almost all aspects. Implementing quarantine monitoring, also social distancing, and contact tracing are a series of processes that can suppress the new infected COVID-19 cases in various countries. Prior works have proposed different monitoring systems to assist the monitoring of individuals in quarantines, as well as many methods are offered for social distancing and contact tracing. These methods focus on one function to provide a reliable system. In this paper, we propose IoT-based quarantine monitoring by implementing a geofence equipped with social distancing features to offer an integrated system that provides more benefits than one system carrying one particular function. We propose a system consisting of a low cost, low complexity, and reusable wristband design and mobile apps to support the quarantine monitoring system. For the geofencing, we propose a GPS-based geofence system that was developed by taking advantage of the convenience offered by the Traccar application. Meanwhile, we add the notification for social distancing feature with adaptive distance measurement RSSI-based set up in the android application. Based on the experiment we did to validate the system, in terms of wristband-to-smartphone communication, scanning interval in smartphone and advertising interval in wristband is best to set in 7 s for both. For social distancing notification and geofence, we measure the system performance through precision, recall, accuracy, and F-measure.
Impact of carrier frequency offset and in-phase and quadrature imbalance on the performance of wireless precoded orthogonal frequency division multiplexing Suyoto Suyoto; Agus Subekti; Arief Suryadi Satyawan; Nasrullah Armi; Chaeriah Bin Ali Wael; Galih Nugraha Nurkahfi
International Journal of Electrical and Computer Engineering (IJECE) Vol 12, No 5: October 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijece.v12i5.pp5153-5163

Abstract

Precoding in orthogonal frequency division multiplexing (OFDM) system proved to reduce the peak-to-average power ratio (PAPR), so that it improves BER. However, from the existing literature, the effect of carrier frequency offset (CFO), in-phase and quadrature (IQ) imbalance on precoded wireless OFDM systems has not been carried out. Therefore, this study evaluated the precoded OFDM (P-OFDM) system performance by considering the impact of CFO and IQ imbalance. P-OFDM performance evaluation is expressed in signal-to-interference noise ratio (SINR) and bit error rates (BER). The communication channels used are the additive white Gaussian noise (AWGN) channel and the frequency-selective Rayleigh fading (FSRF) channel, while the channel equalization process is considered perfect. The results of the analysis and simulation show that P-OFDM is greater affected by the presence of CFO and IQ imbalance than conventional OFDM system. In AWGN channel, P-OFDM experiences different SINR for each subcarrier. This is different from conventional OFDM system, where all SINRs are the same for all subcarriers. In the FSRF channel, both the POFDM system and the OFDM system experience different SINR for each subcarrier, where the SINRs fluctuation in the P-OFDM system is much larger than in the OFDM system.
Co-Authors Agus Subekti Andri Fachrur Rozie Andria Arisal Arief Suryadi Satyawan Arumjeni Mitayani Asih Setiarini Budi Prawara Chaeriah Bin Ali Wael Dayat Kurniawan Mochamad Mardi Martadinata Nasrullah Armi Rendra Dwi Firmansyah Sopyan Setiana Sudirja Sudirja Sulaksono Priyo Suyoto Suyoto Vita Awalia Mardiana