J4 ›› 2018, Vol. 35 ›› Issue (4): 499-506.

• Optical Communication • Previous Articles     Next Articles

Influence of underwater turbulence on channel capacity of orbital angular momentum communication system

HU Tao, PAN Sunxiang, WANG Le, ZHAO Shengmei   

  1. 1 Institute of Signal Processing and Transmission, Nanjing University of Posts and Telecommunications, Nanjing 210003, China; 2 Key Laboratory of Broadband Wireless Communication and Sensor Network Technology, Ministry of Education, Nanjing University of Posts and Telecommunications, Nanjing 210003, China
  • Received:2017-05-17 Revised:2017-05-27 Published:2018-07-28 Online:2018-07-12

Abstract:

Influences of underwater turbulence on the performance of orbital angular momentum (OAM) communication system are investigated. The changes of OAM communication system capacity with different environment parameters and transmission distances are presented. Results show that in underwater turbulence environment, the crosstalk between OAM beam modes is enhanced and channel capacity decreases with the increasing of transmission distance, dissipation rates of turbulent flow and temperature. When the transmission distance approaches 7 m, the channel capacity decreases to half of the original one. When the turbulence kinetic energy dissipation is close to , the capacity decreases to 75% of the theoretical maximum. When the temperature dissipation rate is , the channel capacity reduces to half of the theoretical maximum. In underwater environment, salinity disturbance has a greater influence on the capacity performance than that of temperature disturbance.

Key words: optical communications; orbital angular momentum; underwater turbulence; Laguerre-Gaussian beam; channel capacity

CLC Number: