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A rapid growth of wireless communication system has boosted the exponential development on smart technology while driving a substantial increase in traffic volume. With a highly congested and demand on RF bandwidth spectrum, Visible Light Communication (VLC) seem as a complementary technology towards RF based system which provide wider bandwidth, free and unregulated channel, poses no health hazard, high security and low power consumption leads VLC to be one of the promising technology in data transmission. By maintaining the main purpose of illumination, the exploitation on the existing LED-based lighting system is used as a transmission mechanism to photodetector or image sensor which is used to detect the variations of the light intensity via free space optical channels. Different VLC modulation schemes is review in this paper to see the pros and cons of each scheme implemented in outdoor application specifically for vehicle-to-vehicle (V2V) VLC system. Various type of noises is presented in this paper with the denoising scheme to eliminate or reduce the shot and thermal noise caused by natural sunlight and artificial roadside infrastructure light which degrades the performance of VLC system. [ABSTRACT FROM AUTHOR]

OCDMA is one of the promising optical access technologies because of its notable characteristics, including asynchronous access and enhanced security. In this paper, the author introduced a new universal equation for the DW coding family The universal DW code equation allows for the construction of a new code structure, with either even (EW) or odd (OW) code weights. Contrast this with the previous formula, which contains separate equations for even and odd weights. Double Weight code has a fixed weight value of 2. EW and OW codes are variants of the Double Weight (DW) code family with weights above two. OW is unevenly weighted, while EW is evenly weighted. EW and OW were implemented in transmission connections to reduce noise and Multiple Access Interference (MAI). The revised equations for EW and OW can be used to calculate performance in order to measure the effectiveness of the code. Combining the current MDW and EDW codes yields the new equation. OW performs much better than the Hadamard, MFH, EW, and DW codes. OW can accommodate more than eighty concurrent users. [ABSTRACT FROM AUTHOR]

This study presents the analysis of entanglement using three optical cavities with one microwave cavity. The interactions between intracavity fields that coupled to vibrating end mirrors also been studied. The intense driving of the cavities enables the generation of bipartite entanglement between any two components of the tripartite system. The entanglement sharing between microwave-mechanical and opto-mechanical entanglement lead to the generation of optical-microwave entanglement. Result shows that the entanglement between mechanical resonator with first optical cavity having the highest value of logarithmic negativity, EN. [ABSTRACT FROM AUTHOR]

Mode coupling is the main bandwidth limitation in mode division multiplexing (MDM) systems. A conventional adaptive algorithm for equalization in MDM is the least mean square (LMS), which has a slow convergence rate. In this work, an adaptive minimum mean square error (MMSE) algorithm is modified for improving the convergence rate for equalization in MDM. The MMSE is based on zero-forcing equalizer (ZFE), redistributing the power coupling coefficients of the received transverse field so that the power is coupled back into the same mode as that at the transmitter. This alleviates inter-symbol interference (ISI). The MMSE-based feedforward equalization (FFE) and decision feedback equalization (DFE) MDM is numerically simulated for 1, 2, 3 and 4 channels. Each channel transmits 10 Gbps for a distance of 1300 meters, carried by a distinct linearly polarized mode, through a few mode fiber (FMF), at a wavelength of 1530 nm. The enhanced MMSE equalization scheme showed improvements in the bit error rate (BER), power coupling matrix, eye diagram and convergence rate. [ABSTRACT FROM AUTHOR]