Biblio

This paper investigates the physical-layer data secure transmission for indoor visible light communications (VLC) with simultaneous wireless information and power transfer (SWIPT) and random terminals. A typical indoor VLC system including one transmitter, one desired information receiver and one energy receiver is considered. The two receivers are randomly deployed on the floor, and the random channel characteristics is analyzed. Based on the possibility that the energy receiver is a passive information eavesdropper, the secrecy outage probability (SOP) is employed to evaluate the system performance. A closed-from expression for the lower bound of the SOP is obtained. For the derived lower bound of SOP, the theoretical results match the simulation results very well, which indicates that the derived lower bound can be used to evaluate the secrecy performance. Moreover, the gap between the results of the lower bound and the exact simulation results is also small, which verifies the correctness of the analysis method to obtain the lower bound.

For the security enhancement of the conventional visible light (VL) communication which allows the easy intrusion by adjacent adversary due to visible signal characteristic, the VL communication technique based on the asymmetric Rivest-Shamir-Adleman (RSA) encryption method is proposed for smart indoor service in this paper, and the optimal key length of the RSA encryption process for secure VL communication technique is investigated, and also the error performance dependent on the various asymmetric encryption key is analyzed for the performance evaluation of the proposed technique. Then we could see that the VL communication technique based on the RSA encryption gives the similar RMSE performance independent of the length of the public or private key and provides the better error performance as the signal to noise ratio (SNR) increases.

This paper mainly investigates the physical layer security for visible light communication (VLC) based on spatial modulation (SM). The indoor VLC system includes multiple transmitters, a legitimate receiver and an eavesdropper. In the system, we consider two constraints of the input signal: non-negative and dimmable average optical intensity constraints. According to the principle of information theory and the spatial modulation scheme of uniform selection (US), the upper and the lower bounds on the secrecy rate for SM based VLC are derived, respectively. Numerical results show that the performance gap between the upper and lower bounds of the secrecy rate is small and relatively close, which indicates that the derived secrecy rate bounds can be used to evaluate the system performance. Moreover, when the number of transmitters is set to be one, the spatial modulation disappears, and the secrecy rate bounds in this paper are consistent with the existing results. To further improve the secrecy performance, a channel adaptive selection (CAS) scheme is proposed for selecting the active transmitter. Numerical result indicates that the CAS scheme has better performance than the US scheme.

In this paper, we present a chaos-based information rotated polar coding scheme for enhancing the reliability and security of visible light communication (VLC) systems. In our scheme, we rotate the original information, wherein the rotation principle is determined by two chaotic sequences. Then the rotated information is encoded by secure polar coding scheme. After the channel polarization achieved by the polar coding, we could identify the bit-channels providing good transmission conditions for legitimate users and the bit-channels with bad conditions for eavesdroppers. Simulations are performed over the visible light wiretap channel. The results demonstrate that compared with existing schemes, the proposed scheme can achieve better reliability and security even when the eavesdroppers have better channel conditions.

Variable N-parallel code-shift-keying (VN-CSK) system has been proposed for solving the dimming control problem and the adjacent illumination light interference in illumination light communication. VN-CSK system only focuses on separating the light signal in the illumination light overlapping area. While, it is considerable to transmit a new data using the light overlapping. Visual secret sharing (VSS) scheme is a kind of secret sharing scheme, which distributes the secret data for security and restore by overlapping. It has high affinity to visible light communication. In this paper, a system combined with visible light communication and (2,2)-VSS scheme is proposed. In the proposed system, a modified pseudo orthogonal M-sequence is used that the occurrence probability of 0 and 1 of share is one-half in order to achieve a constant illuminance. In addition, this system use Modified Pseudo-Orthogonal M-sequence(MPOM) for ensuring the lighting function. The bit error rate performance of the proposed system is evaluated under the indoor visible light communication channel by simulation.

Typical techniques for tracking vital signs require body contact and most of these techniques are intrusive in nature. Body-contact methods might irritate the patient's skin and he/she might feel uncomfortable while sensors are touching his/her body. In this study, we present a new wireless (non-contact) method for monitoring human vital signs (breathing and heartbeat). We have demonstrated for the first time1 that vitals signs can be measured wirelessly through visible light signal reflected from a human subject, also referred to as visible light sensing (VLS). In this method, the breathing and heartbeat rates are measured without any body-contact device, using only a simple photodetector and a light source (e.g., LED). The light signal reflected from human subject is modulated by the physical motions during breathing and heartbeats. Signal processing tools such as filtering and Fourier transform are used to convert these small variations in the received light signal power to vitals data.We implemented the VLS-based non-contact vital signs monitoring system by using an off-the-shelf light source, a photodetector and a signal acquisition and processing unit. We observed more than 94% of accuracy as compared to a contact-based FDA (The Food and Drug Administration) approved devices. Additional evaluations are planned to assess the performance of the developed vitals monitoring system, e.g., different subjects, environments, etc. Non-contact vitals monitoring system can be used in various areas and scenarios such as medical facilities, residential homes, security and human-computer-interaction (HCI) applications.

This paper attempts to clarify the concept and applications of Li-Fi technology. The current Wi-Fi network use Radio Frequency waves, but the usage of the available RF spectrum is limited. Therefore a new technology, Li-Fi has come into picture. Li-Fi is a recently developed technology. This paper explains how array of LEDs are used to transmit data in the visible light spectrum. This technology has advantages like security, increased accessible spectrum, low latency efficiency and much higher speed as compared to Wi- Fi. The aim of this research paper is to design a Li-Fi transceiver using Arduino which is able to transmit and receive data in binary format. The software coding is done in Arduino- Uno platform. Successful transmission and reception of data(alphanumeric) has been done.

We propose and demonstrate an indoor optical bi-directional communication system employing near-infrared (NIR) and visible light as carriers. Such a communication technology is attractive wherein red color could be deployed for down streaming purpose via, for instance, LiFi (light fidelity) system, and NIR color for up streaming purpose. This system concept is implemented over a simultaneous bidirectional audio signal transmission and reception over 0.6m indoor wireless channel. Besides, designing the transceiver circuits from off the shelf components, frequency scrambling encryption and decryption technique is also integrated in the system for security purpose. The communication system is optically characterized in terms of line-of-sight laser misalignment and communication distance.

Visible light communication (VLC) is a burgeoning field in wireless communications as it considers illumination and communication simultaneously. The broadcast nature of VLC makes it necessary to consider the security of underlying transmissions. A physical-layer security (PLS) scheme by introducing jamming LEDs is considered in this paper. The secrecy rate of an indoor VLC system with multiple LEDs, one legitimate receiver, and multiple eavesdroppers is investigated. Three distributions of input signal are assumed, i.e., truncated generalized normal distribution (TGN), uniform distribution, and exponential distribution. The results show that jamming can improve the secrecy performance efficiently. This paper also demonstrates that when the numbers of LEDs transmitting information-bearing signal and jamming signal are equal, the average secrecy rate can be maximized.

Internet of Things (IoT) revolution in 5th Generation (5G) will dynamically support all user, devices and customer worldwide where these devices, mechanical and digital machines will be connected and are able to communicate and transfer data over the network. In industries, the evolution of these technologies, known as Industrial IoT (IIoT) will enable machines to be connected and communicate where else, Internet of Everything (IoE) makes the connection more relevant between all smart devices, machines and also people with a huge data, high speed and high security. The growth of these technologies has made Radio Frequency (RF) spectrum resources for wireless communication to be more saturated. In order to solve this problem, new wireless communication technologies are proposed to meet the demand and also to enhance the performance of the system and overcome the existing bandwidth limitations. Studies done shows that Light-Fidelity (Li-Fi), based on Visible Light Communications (VLC) is one of the most promising technology in future which is based on optical wireless communication. Initial study on the Li-Fi concept has focuses on achieving speed, bi-directional transmission concept and supports multiuser access. In this paper we propose a frame work focuses on the handover process for indoor environment by using the steerable Access Point (AP) and compare the output result with fix Access Point.