• Spectroscopy and Spectral Analysis
  • Vol. 42, Issue 3, 970 (2022)
SONG Peng1、1;, CAI Yuan-min1、1; *;, GENG Xiao-jun2、2;, GUO Hua1、1;, JI Han-wu1、1;, and ZHANG Guo-qing3、3;
Author Affiliations
  • 11. School of Electronics and Information, Xi’an Polytechnic University, Xi’an 710048, China
  • 22. Electrical & Computer Engineering Department, California State Univ, Northridge, CA 91330, USA
  • 33. School of Science, Xi’an Polytechnic University, Xi’an 710048, China
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    DOI: 10.3964/j.issn.1000-0593(2022)03-0970-08 Cite this Article
    Peng SONG, Yuan-min CAI, Xiao-jun GENG, Hua GUO, Han-wu JI, Guo-qing ZHANG. Study on Scattering Transmission Characteristics of Wireless UV Communication Based on Particle Size Distribution[J]. Spectroscopy and Spectral Analysis, 2022, 42(3): 970 Copy Citation Text show less

    Abstract

    In the non-line-of-sight wireless ultraviolet communication, particles in the atmosphere scatter ultraviolet light to help transmit information, which offers a broad prospect for applications in near-range covert communication. Haze particles, belonging to the aerosol category, are composed of dust, sulfide, organic hydrocarbon, and other particles in the air. Physical parameters of haze particles, such as size, concentration, and shape, greatly affect the transmission characteristics of wireless ultraviolet light scattering communications. In this work, we first established an ultraviolet multi-scattering model based on the Monte Carlo method. This model considers the effects of two physical quantities of haze particles-radius and concentration. Using this model, we simulated many photons passing through the multi-scattering transmission channel under various haze conditions. The relations of the path loss to particle radius and concentration level are evaluated and analyzed. The results show that: (1) Under the condition of wireless ultraviolet light short-range communication, higher haze concentration results in lower path loss and better system performance; (2) When the communication distance is longer than 500 meters, as the particle concentration continually increases, the system path loss generally decreases first and then increases; (3) With a fixed particle concentration, enlarging the particle radius causes the system path loss to drop initially, but as concentration continues to increase, the path loss rises again. In addition, the particle radius which produces the minimum path loss reduces monotonically as the transmission distance increases. Secondly, we incorporated the particle size distribution of the atmosphere into the model by segmenting the distribution to obtain different particle sizes and corresponding concentrations. Assuming that particles of different sizes and concentrations sequentially scatter photons, the model evaluates the probability of photons arriving at the receiver by passing them through each channel with a single particle size. Then, the model calculates the total probability of photons received and the path loss of the system when particles of all sizes are present. This way, our model creates a realistic multi-scattering transmission environment similar to the actual atmospheric channel where haze particles of all sizes exist simultaneously. Finally, we built an experimental platform to measure the system path loss to communication distance and transmission and receiving elevation angles under three different weather conditions: fine, severe haze, and extremely severe haze. Comparing the measured results of path loss to those from the simulation model, we found that the experimental and simulation results shared the same trend, the communication quality in haze weather is always better than good weather, and larger transmission and reception elevation angles always cause a higher path loss.