Study of PSD Characteristics in Different Modulation Schemes for VLC Systems
نویسندگان
چکیده
Wireless communication technology is emerging very fast with reliable communication lead to emergence of very numerous technologies. There are various modulation schemes suitable in optical wireless communication like OOK, PPM, DPIM and DH-PIM. As modulation techniques is categorized into bandwidth & power efficient but for error performance there are few assumptions where there is no bandwidth limitation. In this paper we analyze the Power Spectral Density (PSD) for every modulation technique in AWGN channel & also the combined result shows that DPIM, DH-PIM are applicable for future applications. Keywords—Visible light communication(VLC), LightFidelity(Li-Fi) , Free space optical communication(FSO), Wireless Fidelity (Wi-Fi) , Intensity Modulation (IM) , Direct Detection(DD) Pulse Position Modulation(PPM), Differential Pulse Interval Modulation(DPIM),Dual Header-Pulse Interval Modulation(DH-PIM),Power Spectral Density(PSD), Fast Fourier Transform(FFT).
منابع مشابه
LED Modulation Characteristics in a Visible-Light Communication System
This paper conducts a research on modulation characteristics of blue light-emitting diodes (LEDs) used in a visible-light communication (VLC) system. Through analysis of the modulation characteristics of LEDs with different emitting sizes, we find that there is a similar linear relationship between LED’s 3dB bandwidth and the operation current density. This experiment also shows that high serie...
متن کاملPerformance of Imaging Receivers using Convex Lens in Indoor MIMO VLC Systems
In multiple-input multiple-output (MIMO) indoor visible light communication (VLC) systems that employ nonimaging receivers, the bit error performance is degraded due to high spatial correlation. Imaging receivers can mitigate this degradation by concentrating the light energy, thereby reducing the correlation among the elements in the channel matrix. In this paper, we investigate the performanc...
متن کاملOptimal Precoder for MIMO Schemes in Indoor Wireless VLC Systems
In multiple-input multiple-output (MIMO) indoor visible light communication (VLC) systems, channel gains are highly correlated. As a result, the bit error rate (BER) of the system is degraded. To improve the BER performance of the system, we propose two precoders, namely, an optimal precoder and a diagonal precoder for MIMO schemes in VLC systems with Nt light emitting diodes (LED) and Nr photo...
متن کاملOptimized Diagonal and Pseudo-random Phase Precoding Schemes for MIMO VLC Systems
Dual-LED complex modulation (DCM) and quadLED complex modulation (QCM) are state-of-the-art MIMO modulation schemes which efficiently transmit complex-valued modulation symbols in visible light communication (VLC). DCM uses two LEDs to transmit complex symbols exploiting their polar form of representation. QCM uses four LEDs to transmit complex symbols through intensity modulation to convey the...
متن کاملSpace Vector Modulation Technique to Reduce Leakage Current of a Transformerless Three-Phase Four-Leg Photovoltaic System
Photovoltaic systems integrated to the grid have received considerable attention around the world. They can be connected to the electrical grid via galvanic isolation (transformer) or without it (transformerless). Despite making galvanic isolation, low frequency transformer increases size, cost and losses. On the other hand, transformerless PV systems increase the leakage current (common-mode c...
متن کامل