LED power consumption in joint illumination and communication system.

This paper addresses the power penalty in an illumination LED caused by visible light communication (VLC). This study models the extra power consumption of the LED by taking into account the convex relation between the dissipated electrical power versus the LED current on one hand and the concave relation between the output luminous flux versus the current on the other hand. The ratio of the output luminous flux to input electrical power, which is known the LED luminous efficacy, is analyzed considering various recombination mechanisms and their dependency on current and temperature. As examples, the rapid light fluctuations induced by Pulse Amplitude Modulation (PAM) and orthogonal frequency division multiplexing (OFDM) are analyzed for joint illumination and communication (JIC) systems. Due to the signal modulation, there is a decrease in the output light of LED. Nevertheless, the total power offered to LED is larger than without modulation and thus extra heating occurs. Moreover, particularly when burst transmission is used in communication networks, visible flicker may occur.

[1]  Yoshihiro Ohno,et al.  Color rendering and luminous efficacy of white LED spectra , 2004, SPIE Optics + Photonics.

[2]  Nadarajah Narendran,et al.  Impact of dimming white LEDs: chromaticity shifts due to different dimming methods , 2005, SPIE Optics + Photonics.

[3]  Nadarajah Narendran,et al.  Spectral and luminous efficacy change of high-power LEDs under different dimming methods , 2006, SPIE Optics + Photonics.

[4]  Ray-Lee Lin,et al.  Equivalent Circuit Model of Light-Emitting-Diode for System Analyses of Lighting Drivers , 2009, 2009 IEEE Industry Applications Society Annual Meeting.

[5]  J. Piprek.  Efficiency droop in nitride‐based light‐emitting diodes , 2010 .

[6]  Guoxing He,et al.  Color temperature tunable white-light light-emitting diode clusters with high color rendering index. , 2010, Applied optics.

[7]  E. Fred Schubert,et al.  Carrier recombination mechanisms and efficiency droop in GaInN/GaN light-emitting diodes , 2010 .

[8]  R. Lin,et al.  Taylor series expression based equivalent circuit models of LEDs for analysis of LED driver system , 2013, 2011 IEEE Industry Applications Society Annual Meeting.

[9]  E. Fred Schubert,et al.  On the symmetry of efficiency-versus-carrier-concentration curves in GaInN/GaN light-emitting diodes and relation to droop-causing mechanisms , 2011 .

[10]  E. Fred Schubert,et al.  Method for determining the radiative efficiency of GaInN quantum wells based on the width of efficiency-versus-carrier-concentration curve , 2012 .

[11]  K. H. Loo,et al.  On the Color Stability of Phosphor-Converted White LEDs Under DC, PWM, and Bilevel Drive , 2012, IEEE Transactions on Power Electronics.

[12]  Junyi Li,et al.  Visible light communication: opportunities, challenges and the path to market , 2013, IEEE Communications Magazine.

[13]  Hongping Zhao,et al.  Analysis of Internal Quantum Efficiency and Current Injection Efficiency in III-Nitride Light-Emitting Diodes , 2013, Journal of Display Technology.

[14]  E. Schubert,et al.  Efficiency droop in light‐emitting diodes: Challenges and countermeasures , 2013 .

[15]  Lutz H.-J. Lampe,et al.  Visible Light Communications Using OFDM and Multiple LEDs , 2015, IEEE Transactions on Communications.

[16]  Liang Wu,et al.  Visible Light Communication System Design and Link Budget Analysis , 2015, Journal of Lightwave Technology.

[17]  Jean-Paul M. G. Linnartz,et al.  Joint illumination and visible-Light Communication systems: Data rates and extra power consumption , 2015, 2015 IEEE International Conference on Communication Workshop (ICCW).

[18]  Dominic C. O'Brien,et al.  High-Speed Integrated Visible Light Communication System: Device Constraints and Design Considerations , 2015, IEEE Journal on Selected Areas in Communications.

[19]  Rafael Perez-Jimenez,et al.  Constraints on drivers for visible light communications emitters based on energy efficiency. , 2016, Optics express.

[20]  Wasiu O. Popoola,et al.  Impact of VLC on Light Emission Quality of White LEDs , 2016, Journal of Lightwave Technology.