Asychronous visible light positioning system using FDMA and ID techniques

In this paper, an indoor localization system making use of LEDs, is proposed and demonstrated in the space of 100 cm × 118.5 cm × 128.7 cm. Different LED lamps transmitted signals with different central frequencies and the identities (IDs) of the transmitters are encoded on the envelopes of the transmitted signals. At the receiver side, the finite impulse response (FIR) filters are applied to discriminate the signals from different lamps. The IDs could be successfully decoded and the received signal strength (RSS) from each transmitter could be achieved. The experimental results show that the average positioning errors of x-scale and y-scale are 1.76 cm and 2.20 cm, respectively.