Patent ID: 11909440
Assignee: SOOCHOW UNIVERSITY
Field: Telecommunications (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 9:
10. The modulation and demodulation method for a visible light communication system according to claim 7, further comprising: calculating a delay time of a rising edge of a first pulse control signal and calculating a delay time of a rising edge of a second pulse control signal, wherein
the calculating a delay time of a rising edge comprises:
determining a light attenuation level of an LED of a light emitter corresponding to a pulse control signal, wherein the pulse control signal is the first pulse control signal or the second pulse control signal; and
calculating a delay time, t
  =
  
   T
   ⁡
   (
   
    1
    -
    
     Ae
     
      -
      
       n
       N
      
     
    
   
   )
  
 

 of a rising edge of a light ray emitted by the light emitter corresponding to the pulse control signal, wherein T is a delay time of a rising edge of an LED bead of the light emitter after test on the last level, A is an attenuation coefficient, and the attenuation coefficient is an absolute value of a tangent slope of a light attenuation curve of the LED bead upon delivery.