Non-line-of-sight Ultraviolet Communication System Research Articles

Performance analysis of MIMO communication system with NLOS UV channel

Performance analysis is carried out, of a multiple input, multiple output (MIMO) ultraviolet (UV) communication system with a non-line-of-sight (NLOS) UV channel. The achievable bit error coefficient is calculated using three spatial multiplexing methods for different bitrate values, azimuthal deviation between the directional diagrams of an optical transmitter and an optical receiver, and different noise levels. Full Text: PDF ReferencesZ. Xu, B. Sadler, "Ultraviolet communications: potential and state-of-the-art", IEEE Commun. Mag. 4667-73 (2009). CrossRef D. Han, Y. Liu, K. Zhang et al., "Theoretical and experimental research on diversity reception technology in NLOS UV communication system", Opt. Expr. 20(14), 15833 (2012). CrossRef Q. Guo, N. He, Z. He, "Research on the channel performances and transmission in UV-LED scatter communications", Study Opt. Comm. 3, 64 (2013). DirectLink G. Chen, L. Liao, Z. Li et al., "Experimental and simulated evaluation of long distance NLOS UV communication", Communication Systems, Networks and Digital Signal Processing (CSND-SP), 9th Int. Symp. on IEEE, 904-909 (2014). CrossRef M.A. El-Shimy, S. Hranilovic, "Spatial-Diversity Imaging Receivers for Non-Line-of-Sight Solar-Blind UV Communications", J. Lightwave Techn. 33(11), 2246 (2015). CrossRef G. Shaw, M. Nischan, M. Iyengar, S. Kaushik, M. Griffin, NLOS UV communication for distributed sensor systems, Proc. SPIE 412683, 96 (2000). CrossRef I.S. Konstantinov, G.S. Vasyliev, O.R. Kuzichkin, D.I. Surzhik, I.A. Kurilov, S.A. Lazarev, "AUV Link Mobile Ad-Hoc Network Examination", J. Eng. Adv. Techn. 8(5S) July 2019 CrossRef I.S. Konstantinov, G.S. Vasilyev, O.R. Kuzichkin, I.A. Kurilov, S.A. Lazarev, "Modeling and Analysis of the Characteristics of Ultraviolet Channels under Different Conditions of Radiation Propagation for the Organization of Wireless AD-HOC Network", J. Adv. Res. Dynam. Contr. Syst. 07, 1853 (2018) DirectLink I.S. Konstantinov, G.S. Vasyliev, O.R. Kuzichkin, D.I. Surzhik, I.A. Kurilov, S.A. Lazarev, "Development Of Uv Communication Channels Characteristics Modeling Algorithm In A Mobile Ad-Hoc Network", J. Adv. Res. Dynam. Contr. Syst. 11(08), 1920 (2019). CrossRef G. Chen, F. Abou-Galala, Z. Xu, B.M. Sadler, "Experimental evaluation of LED-based solar blind NLOS communication links", Opt. Expr. 16(19), 15059 (2008). CrossRef

Secrecy performance of noncoplanar SIMOME NLOS ultraviolet communications over turbulence channels

Abstract This paper considers improving the confidentiality of non-line-of-sight (NLOS) ultraviolet (UV) links within the framework of physical-layer security. We study an NLOS UV scenario with one transmitter, one legitimate receiver and an eavesdropper. The transmitter has only one receive aperture, while the legitimate and unauthorized receivers have multiple receive apertures. Maximum ratio combining (MRC) and equal gain combining (EGC) techniques are utilized to overcome the data rate bottleneck and security risk induced by scattered UV channels and atmospheric turbulence. Alignment errors are exit in the noncoplanar single-input multiple-output multi-apertures eavesdroppers (SIMOME) NLOS UV communication system. The expressions of the average secrecy capacity (ASC), the secrecy outage probability (SOP) and the probability of positive secrecy capacity (PPSC) are derived. It is founded that the smaller the transmit or receive elevation angles are, the better the secrecy performance is. Spatial diversity techniques can improve the confidentiality of NLOS UV links with smaller off-axis errors.

Multi‐user interference in a non‐line‐of‐sight ultraviolet communication network

On the basis of non-line-of-sight (NLOS) multiple-scattering channel characteristic of wireless ultraviolet (UV), the authors designed a UV transmit–receive link model and discussed many aspects of this model. The model is developed by a multiple-scattering Monte Carlo method. They focus on the performance study of NLOS UV communication system with multi-user interference. Numerical simulations are conducted for some application scenarios, where various parameters are changed in the three-dimensional space such as elevation angle of transmitter and receiver, field-of-view angle, full-beam angle and so on. System performance is analysed with simulation results including path loss, signal-to-interference ratio and probability of error (Pe). The results show that reasonable parameter configuration can reduce Pe and improve the performance of communication system.

Non-line-of-sight ultraviolet communication performance in atmospheric turbulence

Non-Line-of-Sight (NLOS) Ultraviolet (UV) communication uses the atmosphere as a propagation medium. As the communication range increases, turbulence becomes a significant atmospheric process that affects the propagation of optical waves. This paper presents a more accurate NLOS channel model by considering turbulence-induced Scintillation Attenuation (SA). Then, the Bit Error Rate (BER) during turbulence of the NLOS UV communication system with On-Off Keying (OOK) modulation and Maximum Likelihood (ML) detection is analysed and compared with that in free space without turbulence. The BER dependence is also analysed for different factors, including the refractive index structure parameter, transceiver range, pointing angles, transmitted power, and data rate.

Characteristics of non-line-of-sight polarization ultraviolet communication channels

This paper investigates characteristics of polarization in non-line-of-sight (NLOS) ultraviolet (UV) communication channels based on a vectorized polarization-sensitive model of NLOS multiple-scatter propagation. The degree of polarization has been analyzed from the following factors: elevation angles, beam angle, field-of-view, off-axis angles, and baseline distance, etc. We draw conclusions that will guide the design of polarization multiplexing technology in NLOS UV communication systems. Outdoor experimentation has validated that this technology is useful to improve the data rate.

Effects of atmosphere visibility on performances of non-line-of-sight ultraviolet communication systems

Dependence of performances of non-line-of-sight (NLOS) solar-blind ultraviolet (UV) communication systems on atmosphere visibility is investigated numerically by correlating the propagation of UV radiation with the visibility. A simplified solar-blind UV atmospheric propagation model is introduced, and the NLOS UV communication system model is constituted based on the single scattering assumption. Using the model, numerical simulation is conducted for two typical geometry configurations and different modulation formats. The results indicate that the performance of the NLOS UV communication system is insensitive to variation of visibility in quite a large range, and deteriorates significantly only in very low-visibility weather, and is also dependent on the geometry configuration of the system. The results also show that the pulse position modulation (PPM) is preferable due to its high-power efficiency to improve the system performance.