Full-duplex wireless light communication using green laser diodes.

The integration of wireless light communication into a wireless fidelity (Wi-Fi) module and gateway enables real-time integrated communication networks that satisfy practical application demands. In particular, wireless green light communication tools can operate underwater and in free-space environments. Here, we design, fabricate, and characterize a full-duplex light communication system using green laser diodes (LDs). Operating within the transmission control protocol/internet protocol (TCP/IP), full-duplex wireless data transmission is confirmed in underwater and free-space environments at a communication rate of 10 Mbps. Through connections to a Wi-Fi module and gateway, the system is accessed by the network via the TCP/IPv4 internet scheme, and real-time video transmission is demonstrated.

All-light communication network for space-air-sea integrated interconnection.

Space-air-sea communication networks are of great interest to meet the demand for close and seamless connections between space, land, and ocean environments. Wireless light communication can expand network coverage from land to the sky and even the ocean while offering enhanced anti-interference capabilities. Here, we propose and establish an all-light communication network (ALCN) for space-air-sea integrated interconnection, which merges underwater blue light communication, wireless white light communication, solar-blind deep ultraviolet light communication and laser diode-based space communication. Ethernet switches and the Transmission Control Protocol are used for space-air-sea light interconnection. Experimental results show that the ALCN supports wired and wireless device access simultaneously. Bidirectional data transmission between network nodes is demonstrated, with a maximum packet loss ratio of 5.80% and a transmission delay below 74 ms. The proposed ALCN provides a promising scheme for future space-air-sea interconnections towards multiterminal, multiservice applications.

Collinear optical links based on a GaN-integrated chip for fiber-optic acoustic detection.

This Letter reports a collinear optical interconnect architecture for acoustic sensing via a monolithic integrated GaN optoelectronic chip. The chip is designed with a ring-shaped photodiode (PD) surrounding a light-emitting diode (LED) of a spectral range from 420-530 nm. The axisymmetric structure helps the coaxial propagation of light transmission and reception. By placing this multiple-quantum wells (MQW)-based device and a piece of aluminum-coated polyethylene terephthalate (Al/PET) film on fiber ends, an ultra-compact acoustic sensing system is built. The sound vibrations can be simply detected by direct measurement of the diaphragm deformation-induced power change. An average signal noise ratio (SNR) of 40 dB and a maximum sensitivity of 82 mV/Pa are obtained when the acoustic vibration frequency changes from 400 Hz to 3.2 kHz. This work provides a feasible solution to miniaturize the sensing system footprint and reduce the cost.