Beacon-enabled TDMA Ultraviolet Communication Network Design and Realization

Non-line of sight (NLOS) ultraviolet (UV) scattering communication can serve as a good candidate for outdoor optical wireless communication (OWC) under non-perfect transmitter-receiver alignment and radio silence. We design and demon-strate a NLOS UV scattering communication network, where a beacon-enabled time-division multiple access (TDMA) multi-node transmission protocol is developed. In our system, light emitting diode (LED) and photomultiplier tube (PMT) are employed for transmitter and receiver devices, respectively. Furthermore, we design protocols for beacon transmission, beacon reception, time compensation, and time slot transition for hardware realization in a field-programmable gate array (FPGA) board based on a master-slave structure, where the master node periodically transmits beacon signals to the slave nodes. We perform field tests for real-time communication network with the transmission range over 110m × 90m, where the network communication system throughput reaches 800 kbps. Experimental results are provided to evaluate the time synchronization error and specify the system key parameters for real-time implementation.