Rate adaptive system for visible light communications

Albayrak, Cenk

doi:10.1109/tsp.2017.8075968

Cited by 6 publications

(4 citation statements)

References 14 publications

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“…The additive message signal from the transmitter passes through the VLC channel. Only the line-of-sight (LOS) component of the transmitted signal is considered [16]. The LOS optical channel gain h m between the LED and the m-th user can be calculated as follows,…”

Section: System Modelmentioning

confidence: 99%

“…The additive message signal from the transmitter passes through the VLC channel. Only the line‐of‐sight (LOS) component of the transmitted signal is considered [16]. The LOS optical channel gain

{h}_m

between the LED and the m ‐th user can be calculated as follows,

{h}_m=\frac{A_{PD}\left(m+1\right)}{2\pi {d}^2}{\cos}^k\left({\phi}_{Txi}\right){T}_s\left(\psi \right)g\left(\psi \right)\cos \left(\psi \right)

where

{A}_{PD}

is the surface area of the PD,

k=\frac{-\ln 2}{\ln \left(\cos {\Omega}_{1/2}\right)}

is the Lambertian index,

{\Omega}_{1/2}

half power semi‐angle of a LED,

d

is the distance between the LED and the PD,

{\phi}_{Txi}

is the angle that the light from the LED to the PD makes with the normal,

\psi

is the angle of incidence of PD,

g\left(\psi \right)=\frac{n^2}{{\mathit{\sin}}^2\phi }

is t...…”

Section: System Modelmentioning

confidence: 99%

See 1 more Smart Citation

Power Allocation for Indoor NOMA Based VLC Systems with Meta‐Heuristic Optimization Algorithms

Altunbas,

Turk

2023

IEEJ Transactions Elec Engng

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Visible light communication (VLC) is a promising technology that realizes short‐range wireless optical communication and illumination simultaneously. The use of light‐emitting diodes (LEDs) in lighting has accelerated the development of short‐range wireless optical technology. However, the limited switching frequency of LEDs used in lighting restricts the communication speed of VLC systems. Non‐orthogonal multiple access (NOMA) methods can be used to improve the sum rate in VLC systems. In this study, meta‐heuristic optimization algorithms are proposed to calculate the power allocation coefficients of users in indoor NOMA‐based VLC systems. During the calculations, many constraints used fairness and optical intensity, which were not taken into account in many studies in the literature. The proposed algorithms are compared with the previously proposed methods according to the sum rate results, considering the number of users increases and the user signal strength values differ. The obtained results revealed that metaheuristic methods demonstrate a significant improvement in terms of sum rate compared to other methods. In addition, the effects of parameters such as sum rate, fairness, and optical intensity on each other are investigated in the simulation environment. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

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Section: System Modelmentioning

confidence: 99%

{h}_m

between the LED and the m ‐th user can be calculated as follows,

{h}_m=\frac{A_{PD}\left(m+1\right)}{2\pi {d}^2}{\cos}^k\left({\phi}_{Txi}\right){T}_s\left(\psi \right)g\left(\psi \right)\cos \left(\psi \right)

where

{A}_{PD}

is the surface area of the PD,

k=\frac{-\ln 2}{\ln \left(\cos {\Omega}_{1/2}\right)}

is the Lambertian index,

{\Omega}_{1/2}

half power semi‐angle of a LED,

d

is the distance between the LED and the PD,

{\phi}_{Txi}

is the angle that the light from the LED to the PD makes with the normal,

\psi

is the angle of incidence of PD,

g\left(\psi \right)=\frac{n^2}{{\mathit{\sin}}^2\phi }

is t...…”

Section: System Modelmentioning

confidence: 99%

Power Allocation for Indoor NOMA Based VLC Systems with Meta‐Heuristic Optimization Algorithms

Altunbas,

Turk

2023

IEEJ Transactions Elec Engng

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“…The identity matrix is

I_{m - q}

and P is the parity check matrix which creates the generator matrix

bold-italicG = false[P_{q \times false(m - q} false) | I_{q}

. The input is encoded by a consequential generator matrix [27].…”

Section: System Modelmentioning

confidence: 99%

Optimal frequency reuse scheme based on cuckoo search algorithm in Li‐Fi fifth‐generation bidirectional communication

Murugaveni

Mahalakshmi²

2020

IET Communications

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“…However, mobility is one of the most desired features by users. To achieve high spectral efficiency for the VLC systems where the channel conditions vary significantly, using rate adaptation methods are essential [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Seamless Rate Adaptation at Receiver Side for Indoor Visible Light Communications by Using Raptor Codes

Albayrak,

Turk,

Tugcu

et al. 2019

Preprint

Self Cite

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Visible light communication (VLC), which uses LEDs for both illumination and communication purposes, has recently emerged as either an alternative or a support system for radio frequency (RF) communication. VLC channel inside a room is highly variable since it is pretty much depends on optical line of sight (LOS) and field of view (FOV) and it causes the received signal to vary dramatically. Therefore, to achieve spectral efficient communication, using rate adaptation methods are essential. In this study, we propose a rateless codes based rate adaptation method which adjusts transmission rate at receiver side and does not require channel state information (CSI) at the transmitter side. Spectral efficiency of proposed method is analyzed and compared with adaptive modulation and coding (AMC) rate adaptation method widely used in literature. For simulation work, we consider a realistic communication system model by using commercially available LEDs and also fulfilling illumination requirements. To overcome multi-path effects, optical orthogonal frequencydivision multiplexing (OFDM) is used. Simulation results indicate that proposed rate adaptive method can achieve seamless rate adaptation and has higher spectral efficiency compared to AMC in presence of significant signal quality variations caused by mobility in a model room.

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Rate adaptive system for visible light communications

Cited by 6 publications

References 14 publications

Power Allocation for Indoor NOMA Based VLC Systems with Meta‐Heuristic Optimization Algorithms

Power Allocation for Indoor NOMA Based VLC Systems with Meta‐Heuristic Optimization Algorithms

Optimal frequency reuse scheme based on cuckoo search algorithm in Li‐Fi fifth‐generation bidirectional communication

Seamless Rate Adaptation at Receiver Side for Indoor Visible Light Communications by Using Raptor Codes

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