Conformal VLC Receivers with Photodetector Arrays: Design, Analysis and Prototype

To enable visible light communication (VLC) for mobile receivers, we design and prototype a wide field-of-view (FOV) optical receiver with off-the-shelf components and in forms that are conformal to the receivers' surface. The VLC system uses high-efficiency optical transmitters with high brightness (7645 Lux in 1 m) low power (36 W) white LED panels which also provide proper lighting. To overcome the detrimental effects of the time-varying inter-symbol interference (ISI) due to the VLC receiver's high acceptance angle and vibration in its structure, we design and utilize an optimal multiple-symbol detection (MSD) algorithm. MSD attains remarkable improvements compared to the symbol-by-symbol detection but with exponential time cost. To decrease the MSD's computing demands, we then design an adaptive Decision Feedback Affine Projection Algorithm (DF-APA). DF-APA attains a notable further improvement with polynomial computation complexity which allows faster response to VLC channel dynamics. We, finally, test the system in presence of intense vibration in the receiver's body and show a 20 Mbps VLC link over 7 m distance.