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2013 - IEEE Communications Magazine

Visible light positioning: a roadmap for international standardization

The widespread introduction of white LEDs for illumination provides a unique opportunity to create an indoor positioning system that is flexible, accurate, and ubiquitous. Signals transmitted by the LEDs are used to determine the position of a person or object within a room. To take full advantage of this new opportunity, it is essential that comprehensive and robust international standards are developed before a plethora of incompatible proprietary systems flood the market. In this article, we discuss the very diverse range of potential applications of these future systems and their implications for the design of a new standard. Another consideration is that the transmission of positioning signals must not compromise the primary function of the LEDs, which is energy-efficient illumination, so visible flicker must be avoided. Position information can be derived from a range of properties of the received signal, such as the power of the received signal or the angle at which the signal reaches the receiver. The suitability of different techniques for an indoor positioning system is considered. Finally, we discuss the implications each of these aspects has for the design of an effective standard.

2013 - Journal of Lightwave Technology

An Indoor Visible Light Communication Positioning System Using a RF Carrier Allocation Technique

We propose a new indoor positioning system utilizing visible light communication. Intensity modulation/direct detection and carrier allocation methods are utilized in the proposed system. Simultaneous three channel transmissions were applied to calculate the receiver's position. The characteristics of the proposed positioning system were investigated through simulation based on the experimental results, and the feasibility of the proposed system was verified by experimentation. The experimental result shows that the average error of estimated positions is reduced to 2.4 cm using adjustment process by normalizing method, which is compared with 141.1 cm without adjustment process.

论文关键词

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