Implementation and performance evaluation of a MIMO-VLC system for data transmissions

The ever-increasing streaming culture of large amounts of data and the need for faster and reliable methods of data transfer has created a space and market for new communication technologies such as Visible Light Communication (VLC). However, the integration of VLC into next generation networks is challenging due to the drawbacks of the technology in terms of atmospheric absorption, shadowing, beam dispersion, etc. One way to overcome some of the challenges is to make use of the multiple input multiple output (MIMO) technique which involves the transmission of data in parallel from multiple sources, increasing the data rate. This paper implements and provides a comprehensive evaluation of a MIMO-VLC system for data transmission. A real experimental test-bed is setup to test the performance of the MIMO-VLC system under various conditions such as distance from the source based on luminous flux, ambient lighting, output power, etc. Additionally, subjective tests are carried out to assess the quality of an audio MIMO VLC link as perceived by the user. The results are compared with the results of a Single Input Single Output (SISO)-VLC system

Implementation and performance evaluation of a MIMO-VLC system for data transmissions

The ever-increasing streaming culture of large amounts of data and the need for faster and reliable methods of data transfer has created a space and market for new communication technologies such as Visible Light Communication (VLC). However, the integration of VLC into next generation networks is challenging due to the drawbacks of the technology in terms of atmospheric absorption, shadowing, beam dispersion, etc. One way to overcome some of the challenges is to make use of the multiple input multiple output (MIMO) technique which involves the transmission of data in parallel from multiple sources, increasing the data rate. This paper implements and provides a comprehensive evaluation of a MIMO-VLC system for data transmission. A real experimental test-bed is setup to test the performance of the MIMO-VLC system under various conditions such as distance from the source based on luminous flux, ambient lighting, output power, etc. Additionally, subjective tests are carried out to assess the quality of an audio MIMO VLC link as perceived by the user. The results are compared with the results of a Single Input Single Output (SISO)-VLC system

Optical Non-Orthogonal Multiple Access for Visible Light Communication

The proliferation of mobile Internet and connected devices, offering a variety of services at different levels of performance, represents a major challenge for the fifth generation wireless networks and beyond. This requires a paradigm shift towards the development of key enabling techniques for the next generation wireless networks. In this respect, visible light communication (VLC) has recently emerged as a new communication paradigm that is capable of providing ubiquitous connectivity by complementing radio frequency communications. One of the main challenges of VLC systems, however, is the low modulation bandwidth of the light-emitting-diodes, which is in the megahertz range. This article presents a promising technology, referred to as "optical- non-orthogonal multiple access (O-NOMA)", which is envisioned to address the key challenges in the next generation of wireless networks. We provide a detailed overview and analysis of the state-of-the-art integration of O-NOMA in VLC networks. Furthermore, we provide insights on the potential opportunities and challenges as well as some open research problems that are envisioned to pave the way for the future design and implementation of O-NOMA in VLC systems

Metameric MIMO-OOK transmission scheme using multiple RGB LEDs

In this work, we propose a novel visible light communication (VLC) scheme utilizing multiple di erent red green and blue triplets each with a di erent emission spectrum of red, green and blue for mitigating the e ect of interference due to di erent colors using spatial multiplexing. On-o keying modulation is considered and its e ect on light emission in terms of flickering, dimming and color rendering is discussed so as to demonstrate how metameric properties have been considered. At the receiver, multiple photodiodes with color filter-tuned on each transmit light emitting diode (LED) are employed. Three di erent detection mechanisms of color zero forcing, minimum mean square error estimation and minimum mean square error equalization are then proposed. The system performance of the proposed scheme is evaluated both with computer simulations and tests with an Arduino board implementatio

Improved Visible Light Communication Receiver Performance by Leveraging the Spatial Dimension

In wireless communications systems, signals can be transmitted as time (temporal) or spatial variants across 3D space, and in both ways. However, using temporal variant communication channels in high-speed data transmission introduces inter-symbol interference (ISI) which makes the systems unreliable. On the other hand, spatial diversity in signal processing reduces the ISI and improves the system throughput or performance by allowing more signals from different spatial locations at the same time. Therefore, the spatial features or properties of visible light signals can be very useful in designing a reliable visible light communication (VLC) system with higher system throughput and making it more robust against ambient noise and interference. By allowing only the signals of interest, spatial separability in VLC can minimize the noise to a greater extent to improve signal-to-noise ratio (SNR) which can ensure higher data rates (in the order of Gbps-Tbps) in VLC. So, designing a VLC system with spatial diversity is an exciting area to explore and might set the foundation for future VLC system architectures and enable different VLC based applications such as vehicular VLC, multi-VLC, localization, and detection using VLC, etc. This thesis work is motivated by the fundamental challenges in reusing spatial information in VLC systems to increase the system throughput or gain through novel system designing and their prototype implementations