Fig. 1.Waveforms in OOK Manchester code transmission. (a) Sync pulse, (b) NRZ input data, (c) Base-band Manchester code, (d) OOK Manchester code with low DC level, and (e) OOK Manchester code with high DC level.
Fig. 3. Configuration of the VLC transmitter.
Fig. 4. Observed waveforms in the VLC transmitter. (a) Sync pulse waveform, (b) NRZ input data waveform, (c) Base-band Manchester code, and (d) OOK Manchester code.
Fig. 5. Observed waveforms in the VLC transmitter. (a) Sync pulse waveform, (b) NRZ data waveform, (c), (d), (e) OOK Manchester codes with low DC level and duty factors of 10%, 50%, 90%, respectively.
Fig. 6. Observed waveforms in the VLC transmitter. (a) Sync pulse waveform, (b) NRZ data waveform, (c), (d), (e) OOK Manchester code with high DC level and duty factor of 10%, 50%, 90%, respectively.
Fig. 7. Configuration of the VLC receiver.
Fig. 8. Observed waveforms in the VLC receiver. (a) Photodiode voltage waveform, (b) OOK modulated sync pulse waveform, and (c) OOK modulated Manchester code waveform.
Fig. 9. Observed waveforms in the VLC receiver. (a) OOK modulated sync pulse waveform, (b), (c), (d) OOK modulated Manchester code with the duty factors of 10%, 50%, 90%, respectively.
Fig. 10. Observed waveforms in the VLC receiver. (a) OOK modulated sync pulse waveform, (b) Recovered base-band sync pulse, (c) OOK modulated Manchester code waveform, (d) Recovered base-band Manchester code, and (e) Recovered NRZ code data.
Fig. 11. Circuit boards used in experiments.
Fig. 2. Average LED optical power versus duty factor.
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