Electronic Shelf Label System Based On Public Illuminating Network

In recent years, Electronic Shelf Label System (ESLS), usually working in an infrared or radio frequency network, has been brought in by some retailers in order to get real time wireless updating of shelf-edge information. However, such system can be realized by using the existing indoor lighting infrastructure with advantages over above solutions. In this paper a new ESLS based on public illuminating network will be proposed. As white light-emitting diodes (WLED) take priority over conventional low luminous efficient lamps and is considered to be the most potential illuminating source in the future, they are used in place of fluorescent lamps and offer extra performance. An analysis of the characteristics of WLED and semiconductor color sensor will be given to show the principle of the physical layer of this system. Unlike the broadcasting manner of common ESLS, PN codes and internal serial numbers are used to differentiate between terminals which enable labels receive messages simultaneously. In network layer, a special combination of space division and time division multiplexing is applied to increase system capacity and decrease refresh time. At the end of this paper, a comparison between common ESLS and this system will be discussed.