Ultraviolet Communication Power Control Based on Particle Swarm Optimization

Ultraviolet (UV) communication has garnered considerable attention as a method utilizing UV particle scattering for signal transmission. However, the significant path loss due to scattering presents challenges in maintaining signal quality in dynamic communication scenarios. Increasing the emitted signal power is not a viable solution due to safety regulations on radiated energy. Therefore, adaptive power control mechanisms are essential. In this paper, we develop a radiation model for UV LED arrays and propose a power optimization method tailored for UV LED arrays in linear communication links. This method accounts for variables such as communication distance, the number of active LEDs, and the transmit power of each LED, integrating both line-of-sight (LOS) and non-line-of-sight (NLOS) components into the receiver power calculation. We formulate an optimization problem with constraints on bit error rate (BER) and control parameters, aiming to minimize transmit power and beam coverage area. The particle swarm optimization (PSO) algorithm is employed to solve this problem. The results indicate that the model we proposed is able to reduce the signal-to-noise ratio (SNR) by 3.05dB to 4.06dB, thereby reducing the transmit power requirements. With BER constraints, the proposed power control strategy ensures energy stabilization across a broad range, with the maximum energy overshoot during distance variations being 41.22%. Compared to power control methods in visible light communication (VLC) systems, the method proposed in this paper is more aligned with the channel characteristics of UV communication. Building on traditional constant-power UV communication systems, the method proposed in this paper can reduce the transmit power by up to 84.24%.