Designs of a free-space white-LED mass-storage transceiver for SD-card file transfer

• Main Authors: Png, Lih Chieh, Le Minh, Nhat, Chen, Liangquan, Yeo, Kiat Seng
• Other Authors: School of Electrical and Electronic Engineering
• Format: Conference or Workshop Item
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/97388; http://hdl.handle.net/10220/12048
• Institution: Nanyang Technological University

Two visible-light mass-storage prototypes have been constructed. They enable file transfers between the SD (Secure Digital) memory card and the PC via white-LED light. The entire system consists of a pair of identical white-LED transceivers: one is connected to the PC, whereas the other is connected to the SD-card subcircuit. File transfer operation is able to execute at 19200 bps. Prototype 1 is based on pulse-position modulation (PPM), while Prototype 2 is based on pulse-width modulation (PWM). It was found that the PPM design consumes less power and is more stable. Full-speed (12 Mbps) USB 2.0 VLC transceiver designs for slave and host devices are also included.