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Fuzzy Based Network Assignment and Link-Switching Analysis in Hybrid OCC/LiFi System
Hasan, Moh. Khalid,Chowdhury, Mostafa Zaman,Shahjalal, Md.,Jang, Yeong Min WILEY INTERSCIENCE 2018 WIRELESS COMMUNICATIONS AND MOBILE COMPUTING Vol.2018 No.-
<P>In recent times, optical wireless communications (OWC) have become attractive research interest in mobile communication for its inexpensiveness and high-speed data transmission capability and it is already recognized as complementary to radio-frequency (RF) based technologies. Light fidelity (LiFi) and optical camera communication (OCC) are two promising OWC technologies that use a photo detector (PD) and a camera, respectively, to receive optical pulses. These communication systems can be implemented in all kinds of environments using existing light-emitting diode (LED) infrastructures to transmit data. However, both networking layers suffer from several limitations. An excellent solution to overcoming these limitations is the integration of OCC and LiFi. In this paper, we propose a hybrid OCC and LiFi architecture to improve the quality-of-service (QoS) of users. A network assignment mechanism is developed for the hybrid system. A dynamic link-switching technique for efficient handover management between networks is proposed afterward which includes switching provisioning based on user mobility and detailed network switching flow analysis. Fuzzy logic (FL) is used to develop the proposed mechanisms. A time-division multiple access (TDMA) based approach, called round-robin scheduling (RRS), is also adopted to ensure fairness in time resource allocation while serving multiple users using the same LED in the hybrid system. Furthermore, simulation results are presented taking different practical application scenarios into consideration. The performance analysis of the network assignment mechanism, which is provided at the end of the paper, demonstrates the importance and feasibility of the proposed scheme.</P>
Application-Based Comparative Performance Analysis of Visible Light Communication Technologies
Moh. Khalid Hasan,Md. Shahjalal,Mostafa Zaman Chowdhury,Yeong Min Jang 한국통신학회 2019 한국통신학회 학술대회논문집 Vol.2019 No.1
Currently, communications using optical spectrum has become extremely potential as it can be utilized as congruent complementary of the radio-frequency-based technologies. Using visible light for communication can provide high data rate utilizing the high flickering rates of currently available lightemitting diodes (LED). Visible light communication (VLC) technologies are characterized by the receiver types. Two types of receivers are available to receive data from LEDs: photo detector and image sensors of camera. In this paper, we briefly investigate the performance of different VLC technologies considering respective receiver-types. We perform our analysis based on different service scenarios. Simulation results shows that PD-based communication achieves a low signal-to-noiseplus- interference ratio compared to the image sensor-based communication. However, the overall capacity is higher for PD.
Optimum LED Coverage Utilization in OCC for Effective Communication with Mobile Robot
Moh. Khalid Hasan,Mostafa Zaman Chowdhury,Md. Shahjalal,Md. Mainul Islam,장영민 한국통신학회 2020 Journal of communications and networks Vol.22 No.5
Optical camera communication (OCC) is a promisingtechnology for camera-mounted mobile robots (MRs), where it canuse its camera to communicate with light-emitting diode (LED) infrastructures. Due to the limited angle of view of current commercial cameras used in MRs, the cameras cannot detect LED everywhere inside an area illuminated by an LED; hence, much ofthe illumination surface remains unutilized. Herein, we propose anautomatic camera inflection algorithm to successfully detect LEDanywhere inside an LED cell (the total coverage area illuminatedby LED). The inflection mechanism is a supervised learning approach. The technique utilizes the coordinate information (i.e., Xand Y coordinates) of an LED cell, which is further employed totrack the position of the LED. The coordinate data is automaticallyupdated when the MR travels from one position to another. Furthermore, we perform simulations that include a discussion on tiltangle variation with increasing distance traveled by the MR and aperformance analysis that demonstrates the importance and feasibility of the developed algorithm. Finally, a testbed prototype forOCC is implemented to demonstrate the proof of angle measurement theory and bit-error-rate performance of the proposed system.