Advantages, disadvantages of OCC, Optical Camera Communication
This page covers advantages and disadvantages of OCC i.e. Optical Camera Communication and its basics. It mentions benefits or advantages of OCC (Optical Camera Communication) and drawbacks or disadvantages of OCC (Optical Camera Communication).
What is OCC (Optical Camera Communication) ?
The technology use devices having a flash and a camera as transceiver pair. Majority of devices are equipped with front and/or rear cameras with LED flashes.
Optical Wireless Communication systems are implemented using LEDs, displays or other light sources as the transmitter and a camera (or Image sensor (IS) ) as the receiving module.
Following are the major features of OCC system.
• It uses both infrared (IR) and Visual Light (VL) frequencies.
• It can use only LEDs unlike VLC system which uses both LEDs and Laser Diodes.
• It uses camera (or IS) as receiver.
Working of OCC system:
As shown in the figure, the data transmitted from two different LED transmitters can be captured easily and distinguished simultaneously by using Image sensor (i.e. IS). Background noise sources such as sunlight, ambient light and digital signage can be discarded by separating the pixels associated with such noise sources. In this manner, IS can provide secure, interference free and reliable communications even in outdoor conditions.
Following are the common applications of OCC (Optical Camera Communication).
• V2X communication
• Indoor positioning
• Digital Signage
• Drone to drone communication
• Augmented Reality/Virtual reality
• Motion detection and recognition
• Data sharing
Benefits or advantages of OCC
Following are the benefits or advantages of OCC:
➨It offers non-interference based communication link due to use of Image sensor. Image sensor uses huge number of pixels and hence lights from different sources are separated almost perfectly. Optical signals are derived separately from each pixel. Hence signals do not get mixed. This enables communication even in the presence of light signals and ambient lights e.g. sunlight and streetlights.
➨It offers higher SNR (Signal to Noise Ratio).
➨LEDs which are not needed by receivers are omitted and hence there is no need for complex signal processing to filter out unnecessary information.
➨It offers stable communication against changing distance as long as imaged LED size is not smaller than size of the pixel.
➨It makes use of infrared and visual light frequencies, hence it leverages benefits of both infrared and visual light.
Drawbacks or disadvantages of OCC
Following are the drawbacks or disadvantages of OCC:
➨The optical communication is Line of Sight (LOS) and hence its links will get blocked by any object which prevents light penetration. The common objects are Buildings, walls, thick fog, thick gas etc.
➨The OCC technology does not support high data rate communication. This is due to low frame rates supported by traditional cameras. Image sensors support frame rate of about 30 fps.
➨To overcome above and to attain higher data rates, high speed cameras of latest Image sensors are required. This increases cost of the OCC system.
➨Human eye will detect light flickering if a signal is transmitted at lower frequency by using visual light sources. This is observed in low frame rate commercial cameras.