An optoelectronic characterization of the devices used in the integrated system is presented to support the main results, namely the decoding strategy. The photodetector is a pin-pin heterostructure that works as an optical filter, presenting a selective spectral sensitivity dependent on the external optical bias. The red and blue light emitted from the white RGB LEDs were modulated at different frequencies. With this configuration each cardinal direction becomes assigned to a specific set of optical excitation (wavelength and frequency). The decoding of the output photocurrent allows the identification of the input optical signals and the determination of the correspondent spatial direction. The localization algorithm makes use of the Fourier transform to identify the frequencies present in the photocurrent signal and the wavelength filtering properties of the sensor under front and back optical bias to detect the existing red and blue signals. The viability of the system is demonstrated through the implementation of an automatic algorithm to infer the photodetector cardinal direction. Additional research on the light intensity is presented to investigate the accuracy of the spatial position along a cardinal direction. |
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CITATIONS
Cited by 2 scholarly publications.
Photodetectors
Light emitting diodes
Telecommunications
Visible radiation
Fourier transforms
Light sources and illumination
Optoelectronic devices