Optical and Quantum Electronics

, Volume 45, Issue 8, pp 901–905 | Cite as

Simple digital FIR equalizer design for improving the phosphor LED modulation bandwidth in visible light communication



We propose and demonstrate a simple digital post-equalization technique to improve the bandwidth-limitation of light-emitting-diode (LED) visible-light-communication (VLC) channel. The design of finite-impulse-response equalizer according to the channel response is presented to improve the bandwidth limitation of LED VLC channel. Here, no optical blue filter is used. The simulation and experimental results show \(\sim \)10 times enhancement of the direct modulation speed of white-light LED VLC system. When compares with the previous demonstration using high-pass equalization circuit constructed by lumped capacitor and resistor, the proposed scheme shows an improvement in signal quality and transmission distance, and a 10 Mbit/s error-free free-space transmission over 1 m can be achieved under the bit error rate of \(< 10^{-9}\).


Visible light communication (VLC) FIR filter Access network LED 


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • C. H. Yeh
    • 1
    • 4
  • C. W. Chow
    • 2
    • 3
  • Y. F. Liu
    • 2
    • 3
  • P. Y. Huang
    • 2
    • 3
  1. 1.Information and Communications Research LaboratoriesIndustrial Technology Research Institute (ITRI)HsinchuTaiwan
  2. 2.Department of PhotonicsNational Chiao Tung UniversityHsinchuTaiwan
  3. 3.Institute of Electro-Optical EngineeringNational Chiao Tung UniversityHsinchuTaiwan
  4. 4.Graduate Institute of Applied Science and EngineeringFu Jen Catholic UniversityNew TaipeiTaiwan

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