Biblio

In this paper, we propose a numerical simulation investigation of the wavelength division multiplexing mechanism between a chaotic secure channel and a traditional fiber channel using the advanced modulation method DP-16QAM at the bitrate of 80Gbps, the fiber length of 80 km and 100 GHz channel spacing in C-band. Our paper investigates correlation coefficients between the transmitter and also the receiver for two forms of communication channels. Our simulation results demonstrate that, in all cases, BER is always below 2.10-4 even when we have not used the forward-error-correction method. Besides, cross-interaction between the chaotic channel and also the non-chaotic channel is negligible showing a highly independent level between two channels.

A Visible Light Communication (VLC) is a fast growing technology became ubiquitous in the Optical wireless communication domain. It has the benefits of high security, high bandwidth, less power consumption, free from Electro Magnetic radiation hazards. VLC can help to address the looming spectrum crunch problem with secure communication in an unlimited spectrum. VLC provides extensive wireless connectivity with larger data densities than Wi-Fi along with added security features that annihilate unwanted external network invasion. The problem such as energy consumption and infrastructure complexity has been reduced by integrating the illumination and data services. The objective is to provide fast data communication with uninterrupted network connectivity and high accuracy to the user. In this paper, a proposed visible light communication system for transmitting text information using amplitude shift keying modulation (ASK) has been presented. Testing of transmitter and receiver block based on frequency, power and distance has been analyzed. The results show that the receiver is capable of receiving input data with minimum length under direct communication with the transmitter.

This paper represents the experimental implementation of an encryption-based visible light communication system for indoor communication over 14m, two single LED transmitters as the data source, and four receivers considered as data receivers for performance evaluation.

A conventional visible light communication system consists of a transmitter, a jammer that includes a few light emitting diodes, a legal listener and an eavesdropper. In this work, a similar system is designed with a collimating lens in order to create an extra layer of practical physical security measure. The use of a collimating lens makes it available to spatially limiting data transmission to an area under the lensed transmitter. Also focused data transmission through the optical lens, increases the secrecy rate. To investigate the applicability of the proposed design we designed a sample experimental setup using USRP and implemented in a laboratory environment. In the proposed set up, the receiver is in a fixed position. However, it is possible to implement an easy, practical and cheap hardware solution with respect to a beamforming type VLC that uses directional beam forming method to establish transmission to a dynamic target. In addition, it is achievable to control the size of the area where a receiver can access data by manipulating the distance between the optical lens and transmitter.

This paper proposes a novel zero-forcing (ZF) beamforming strategy that can simultaneously cope with active and passive eavesdroppers (EDs) in visible light communication systems. A related optimization problem is formulated to maximize the signal-to-noise ratio (SNR) of the legitimate user (UE) while suppressing the SNR of active ED to zero and constraining the average SNR of passive EDs. The proposed beamforming directs the transmission along a particular eigenmode related to the null space of the active ED channel and the intensity of the passive ED point process. An inverse free preconditioned Krylov subspace projection method is used to find the eigenmode. The numerical results show that the proposed ZF beamforming scheme yields better performance relative to a traditional ZF beamforming scheme in the sense of increasing the SNR of the UE and reducing the secrecy outage probability.

Visible light communication (VLC) is considered as an emerging system for wireless indoor multimedia communications. As any wireless communication system, its channels are open and reachable to both licensed and unlicensed users owing to the broadcast character of visible-light propagation in public areas or multiple-user scenarios. In this work, we consider the physical-layer security approaches for VLC to mitigate this limitation. The physical-layer security approaches can be divided into two categories: keyless security and key-based security approaches. In the last category, recently, the authors introduced physical-layer key-generation approaches for optical orthogonal frequency division multiplexing (OFDM) systems. In these approaches, the cyclic prefix (CP) samples are exploited for key generation. In this paper, we study the effect of the length of key space and order of modulation on the security level, BER performance, and key-disagreement-rate (KDR) of the introduced key-based security approaches. From the results, our approaches are more efficient in higher order of modulation as the KDR decreases with the increase of order of modulation.

Wireless communication in the field of radio frequency (RF) have modernized our society. People experience persistent connection and high-speed data through wireless technologies like Wi-Fi and LTE while browsing the internet. This causes congestion to network; users make it difficult for everyone to access the internet or to communicate reliably on time. The major issues of RF spectrum are intrusion, high latency and it requires an individual transmitter receiver setup in order to function. Dr. Herald Hass came up with an idea of `data through illumination'. Surmounting the drawbacks of RF spectrum, visible light communication (VLC) is more favored technique. In intelligent transportation system (ITS), this evolving technology of VLC has a strong hold in order to connect vehicle-to-infrastructure (V2I) and vehicle-to-vehicle (V2V) links wirelessly. Indoor VLC applications have been studied deeply while the field of vehicular VLC (V-VLC) networking is relatively a less researched domain because it has greater level of intrusion and additive ambient light noise is higher in outdoor VLC. Other factors due to which the implementation of VLC faces a lot of hurdles are mostly related to environment such as dust, haze, snow, sunlight, rain, fog, smog and atmospheric disturbances. In this paper, we executed a thorough channel modelling in order to study the effects of clear weather, fog, snow and rain quantitatively with respect to different wavelengths in consideration for an ITS. This makes ITS more robust in nature. The parameters under consideration will be signal-to-noise ratio (SNR), bit error rate (BER) and optical power received (OPR) for different LED wavelengths.

This talk presents an overview of the latest visible light communication (VLC) and underwater wireless optical communication (UWOC) research and development from the device to the system level. The utilization of laser-based devices and systems for LiFi and underwater Internet of Things (IoT) has been discussed.

The rate at which a secure key can be generated in a quantum key distribution (QKD) protocol is limited by the channel loss and the quantum bit-error rate (QBER). Increases to the QBER can stem from detector noise, channel noise, or the presence of an eavesdropper, Eve. Eve is capable of obtaining information of the unsecure key by performing an attack on the quantum channel or by listening to all discussion performed via a noiseless public channel. Conventionally a QKD protocol will perform the information reconciliation over the authenticated public channel, revealing the parity bits used to correct for any quantum bit errors. In this invited paper, the possibility of limiting the information revealed to Eve during the information reconciliation is considered. Using a covert communication channel for the transmission of the parity bits, secure key rates are possible at much higher QBERs. This is demonstrated through the simulation of a polarization based QKD system implementing the BB84 protocol, showing significant improvement of the SKRs over the conventional QKD protocols.

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.

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.

An experiment and numerical simulations analyze low-speed OSC derived XPM-induced phase noise penalty in 100-Gbps WDM systems. WDM transmission performance exhibits signal bit-pattern dependence on OSC, which is due to deterioration in SD-FEC performance.

Multiple-input multiple-output (MIMO) techniques are currently the de facto approach for increasing the capacity and reliability of communication systems. Spatial modulation (SM) is presently one of the most eminent MIMO techniques. As, it combines the advantages of having higher spectral efficiency than repetition coding (RC) while overcoming the inter-channel interference (ICI) faced by spatial multiplexing (SMP). Moreover, SM reduces system complexity. In this paper, for the first time in literature, the use of MIMO techniques is explored in Internet-of-Things(IoT) deployments by introducing a novel technique called security aware spatial modulation (SA-SM).SA-SM provides a low complexity, secure and spectrally efficient technique that harvests the advantages of SM, while facing the arising security concerns of IoT systems. Using an undemanding modification at the receiver, SA-SM gives an extra degree of technology independent physical layer security. Our results show that SA-SM forces the bit-error-rate (BER) of an eavesdropper to not exceed the range of 10-2, which is below the forward-error-correction (FEC) threshold. Hence, it eradicates the ability of an eavesdropper to properly decode the transmitted signal. Additionally, the efficiency of SA-SM is verified in both the radio and visible light ranges. Furthermore, SA-SM is capable of reducing the peak-to-average-power-ratio (PAPR) by 26.2%.

We propose a secure key generation and distribution scheme for data encryption in classical optical fiber channel. A Delay interferometer (DI) is used to track the random phase fluctuation inside fiber, while the reconfigurable lengths of polarization-maintaining (PM) fiber are set as the source of optical phase fluctuations. The output signals from DI are extracted as the secret key and shared between the two-legal transmitter and receiver. Because of the randomness of local environment and the uniqueness of fiber channel, the phase fluctuation between orthogonal polarization modes (OPMs) can be used as secure keys to enhance the level of security in physical layer. Experimentally, we realize the random key generation and distribution over 25-km standard single-mode fiber (SSMF). Moreover, the proposed key generation scheme has the advantages of low cost, compatible with current optical fiber networks and long distance transmission with optical amplifiers.

Considering reflected light in physical layer security (PLS) is very important because a small portion of reflected light enables an eavesdropper (ED) to acquire legitimate information. Moreover, it would be a practical strategy for an ED to be located at an outer area of the room, where the reflection light is strong, in order to escape the vigilance of a legitimate user. Therefore, in this paper, we investigate the impact of multipath reflections on PLS in visible light communication in the presence of randomly located eavesdroppers. We apply spatial point processes to characterize randomly distributed EDs. The generalized error in signal-to-noise ratio that occurs when reflections are ignored is defined as a function of the distance between the receiver and the wall. We use this error for quantifying the domain of interest that needs to be considered from the secrecy viewpoint. Furthermore, we investigate how the reflection affects the secrecy outage probability (SOP). It is shown that the effect of the reflection on the SOP can be removed by adjusting the light emitting diode configuration. Monte Carlo simulations and numerical results are given to verify our analysis.

Wireless communication based on optical spectrum has been a promising technology to support increasing bandwidth demand in the recent years. Light fidelity, optical camera communication, visible light communication, underwater optical wireless communication, free space optical communication are such technologies those have been already deployed to support the challenges in wireless communications. Those technologies create massive data traffic as lots of infrastructures and servers are connected with the internet. Software defined optical wireless networks have been introduced in this paper as a solution to this phenomenon. An architecture has been designed where we provide the general software defined networking (SDN) structure and describe the possible tasks which can be performed by the SDN for optical wireless communication.

In the indoor scenario, visible light communications (VLC) is regarded as one of the most promising candidates for future wireless communications. Recently, the physical layer security for indoor VLC has drawn considerable attention. In this paper, the secrecy capacity of indoor VLC is analyzed. Initially, an VLC system with a transmitter, a legitimate receiver, and an eavesdropper is established. In the system, the nonnegativity, the peak optical intensity constraint and the dimmable average optical intensity constraint are considered. Based on the principle of information theory, the closed-form expressions of the upper and the lower bounds on the secrecy capacity are derived, respectively. Numerical results show that the upper and the lower bounds on secrecy capacity are very tight, which verify the accuracy of the derived closed-form expressions.

We evaluate the use of LEDs intended for illumination as low-cost filtered optical detectors. An optical wireless system that is exclusively based on commercial off-the-shelf 5-mm R/G/B LEDs is experimentally demonstrated for Gb/s close-proximity transmission.

In this paper, a method is proposed for improving the physical layer security for indoor visible light communication (VLC) networks with angle diversity transmitters. An angle diversity transmitter usually consists of multiple narrow-beam light-emitting diode (LED) elements with different orientations. Angle diversity transmitters are suitable for confidential data transmission, since data transmission via narrow light beams can effectively avoid the leakage of messages. In order to improve security performance, protection zones are introduced to the systems with angle diversity transmitters. Simulation results show that over 50% performance improvement can be obtained by adding protection zones.

The broadcast nature of visible light beam has aroused great concerns about the privacy and confidentiality of visible light communication (VLC) systems.In this paper, in order to enhance the physical layer security, we propose a channel scrambling scheme, which realizes orthogonal factorized channel scrambling with location information embedded (OFCS-LIE) for the VLC systems. We firstly embed the location information of the legitimate user, including the transmission angle and the distance, into a location information embedded (LIE) matrix, then the LIE matrix is factorized orthogonally in order that the LIE matrix is approximately uncorrelated to the multiple-input, multiple-output (MIMO) channels by the iterative orthogonal factorization method, where the iteration number is determined based on the orthogonal error. The resultant OFCS-LIE matrix is approximately orthogonal and used to enhance both the reliability and the security of information transmission. Furthermore, we derive the information leakage at the eavesdropper and the secrecy capacity to analyze the system security. Simulations are performed, and the results demonstrate that with the aid of the OFCS-LIE scheme, MIMO-based VLC system has achieved higher security when compared with the counterpart scrambling scheme and the system without scrambling.

Visible light communications is an emerging architecture with unlicensed and huge bandwidth resources, security, and experimental implementations and standardization efforts. Display based transmitter and camera based receiver architectures are alternatives for device-to-device (D2D) and home area networking (HAN) systems by utilizing widely available TV, tablet and mobile phone screens as transmitters while commercially available cameras as receivers. Current architectures utilizing data hiding and unobtrusive steganography methods promise data transmission without user distraction on the screen. however, current architectures have challenges with the limited capability of data hiding in translucency or color shift based methods of hiding by uniformly distributing modulation throughout the screen and keeping eye discomfort at an acceptable level. In this article, foveation property of human visual system is utilized to define a novel modulation method denoted by FoVLC which adaptively improves data hiding capability throughout the screen based on the current eye focus point of viewer. Theoretical modeling of modulation and demodulation mechanisms hiding data in color shifts of pixel blocks is provided while experiments are performed for both FoVLC method and uniform data hiding denoted as conventional method. Experimental tests for the simple design as a proof of concept decreases average bit error rate (BER) to approximately half of the value obtained with the conventional method without user distraction while promising future efforts for optimizing block sizes and utilizing error correction codes.

In this paper, we introduce an optical network with cross-layer security, which can enhance security performance. In the transmitter, the user's data is encrypted at first. After that, based on optical encoding, physical layer encryption is implemented. In the receiver, after the corresponding optical decoding process, decryption algorithm is used to restore user's data. In this paper, the security performance has been evaluated quantitatively.