1. March 2017
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title : Technical considerations for OCC data rate enhancement
Date Submitted : [Sep, 2018]
Source : Moh. Khalid Hasan, Mostafa Zaman Chowdhury, Md. Shahjalal, and Yeong Min Jang
Company : [Kookmin University]
Address : [Seoul, Korea]
Voice : [ ],
Re :
Abstract : This document discusses about possible considerations to enhance the data rate for OCC.
Purpose : To enhance the data rate with using existing modulation techniques.
Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein.
Release : The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P
Slide 1
Submission

2. Introduction
Currently radio frequency (RF) band is extensively used for communication purposes which is strictly regulated and is not sufficient for the future data traffic.
Different visible light communication (VLC) technologies are introduced as complementary to RF.
Most of the VLC technologies suffer from severe interference from sunlight and other ambient light sources.
Optical camera communication (OCC) is a promising technology which is less affected from interferences.
OCC can be used as a significant solution in the vehicular assistance technologies (VAT).

3. Technical Requirements for high data rate
Transmitter Requirements:
High LED flickering rate.
Narrow angle emission pattern.
Multi-hop data transmissions.
Receiver requirements:
Image sensor with high density of image pixels.
Enhanced focal length of camera
Enhanced shutter speed.

4. Shutter speed synchronization
Shutter speed indicate the on and off speed of camera shutter.
It indicates how much time a frame is exposed to illumination.
Unsynchronized shutter speed results in high packet error rate.
Also low shutter speed increases the bit error rate.
Shutter speed must be more than twice of the sampling rate of camera.
The synchronization of shutter speed with the LED flickering rate determines how many bits will be transmitted over one exposure of image frames.

5. Data rate enhancement
If the shutter speed is very high, then the camera flickering rate could be increased, which will increase the overall data rate.
After synchronization, the number of detectable databits can be represented as

6. Discussion fs and fr are the shutter speed and frame, respectively.
The figure shows different achievable payload size with respect to exposure time for different LED flickering rates.

7. Conclusion
By transmitting a large number of bits per every exposure, the data rate can be increased to a great extent.
This technique can be employed for any existing modulation schemes.
OCC with enhanced data rate will be a significant choice for communication in vehicular and other perspectives.