RGB Synchronous VLC modulation scheme for OCC

Simulation of Rolling Shutter Acquisition in Optical Camera Communications

“…The implementation of the simulator has been carried out using Python (with Numpy, Scipy and Matplotlib libraries). The experimental setup shown in a previous work [6] was modified and used to define key parameters of the simulation. Real image frames were taken using an experimental setup, shown in Fig.…”

“…For each pixel, Eq. 6 is applied: (6) where i(x, y, c) is the output pixel current at the c − th channel,S(x, y, λ) is the pixel's energy-normalized input spectrum, F c (λ) is the c − th channel filter response, and R(λ) is the substrate's responsivity (typically Silicon).…”

Wireless Sensor Networks Using Sub-Pixel Optical Camera Communications: Advances in Experimental Channel Evaluation

“…OCC’s main limitations can be grouped in three categories: those related to the image-forming capability, where the distortions caused by the optics are a source of interference and noise, especially relevant in screen-to-camera communications [ 30 ]; issues related to the timing of capturing and the synchronization with transmission [ 12 , 13 ], in which the slight variations of the camera frame along with the gaps between frame acquisitions induce errors in data decodification; and the important challenges related to the discovery of nodes and their tracking in motion [ 31 ], where the time elapsed by computer vision algorithms in the detection of the ROI can have a considerable impact on the latency.…”

“…The packet structure proposed for GS detection is depicted in Figure 5 , with a symbol rate of 7.5 baud for cameras using 30 fps frame rate. In the case of RS detection, much higher symbol rates can be employed, proportional to the row-shift time, as described in [ 13 ]. The RS experiment used a symbol rate of 8.4 baud, and exploited the color channels of the camera, with three parallel data streams using RGB LEDs.…”

“…However, in all these works mentioned above, it is assumed that the projected area of the light source in the image affects a high number of pixels, as shown in Figure 1 . In this case, the lamp’s geometric projection occupies a significant portion of the image [ 12 , 13 ]. This previous consideration has a final impact on the maximum distance of the link, making it necessary either to use luminous surfaces with an extensive area or to use telescopic lenses, which reduce the FOV, as mentioned before.…”