| （英） |
In recent years, the underwater simultaneous light wave information and transfer (USLIPT) system has attracted attention as a technology that achieves wireless power transfer and communication using visible light for underwater drones. As modulation schemes for USLIPT, pulse amplitude modulation (PAM) and optimal color shift keying (OCSK) have been investigated, and OCSK using multi-color laser diodes (LDs) can improve communication performance by selecting the optimum wavelength according to water quality. Also, optimizing the ratio of power supply and communication at the receiver (receiver optimization) can improve harvested energy while satisfying the desired communication performance.
On the other hand, the use of USLIPT in shallow water is expected to be affected by solar noise, but it has not yet been investigated for optimal wavelength and receiver optimization for USLIPT under sunlight noise. Therefore, in this paper, the effects of sunlight noise on harvested energy were evaluated by simulation. In particular, the PAM with single LD and the OCSK with multi-color LDs are adopted, and the optimal wavelength when using receiver optimization is investigated.
The results show that when the water depth is 20 m and the distance between the transmitter and receiver is 10 m, the harvested energy can be increased if the communication can be maintained. On the other hand, when the influence of solar noise increases, the communication performance cannot be achieved in receiver optimization and energy harvesting becomes impossible, but OCSK using multi-color LDs shows less degradation. |