Fig. 1. (Color online) The block diagram of the system.

Fig. 2. (Color online) (a) Optical microscope image of an MQW diode; (b) I−V and LOP plots of the MQW diode; the inset shows optical images of the diode biased at 0 and 2.43 V; (c) measured EL and responsivity spectra of the MQW diode; (d) photocurrent of the MQW receiver versus the injection current of the MQW transmitter.

Fig. 3. (Color online) Schematic diagram of TDM light communication using two identical blue MQW diodes.

Fig. 4. (Color online) (a) Photocurrent of the MQW receiver versus the offset voltage of the MQW transmitter; (b) 3-dB bandwidth versus the offset voltage of the MQW transmitter; (c) 3-dB bandwidth versus the offset voltage of the MQW receiver.

Fig. 5. (Color online) Schematic diagram of the transmitter and receiver circuits within a single time slot.

Fig. 6. (Color online) (a) Comparisons between PRBS signals at different transmitting nodes; (b) comparisons between PRBS signals at different receiving nodes; (c) eye diagram measured at a communication rate of 100 kbps; (d) comparisons between audio signals transmitted and received.

Fig. 7. (Color online) (a) Exploded view of the mobile blue-light TDM communication system; (b) mobile blue-light TDM communication system.

Fig. 8. (Color online) (a) and (b) Mobile underwater TDM audio communication through a water tank.