摘要
Given the enhanced channel capacity of wave chirality,acoustic communications based on the orbital angular momentum(OAM)of acoustic-vortex(AV)beams are of significant interest for underwater data transmissions.However,the stringent beam alignment is required for the coaxial arrangement of transceiver arrays to ensure the accuracy and reliability of OAM decoding.To avoid the required multiple measurements of the traditional orthogonality based algorithm,the beam alignment algorithm based on the OAM spectrum decomposition is proposed for AV communications by using simplified ring-arrays.Numerical studies of the single-OAM and OAM-multiplexed AV beams show that the error of the OAM spectrum increases with the translation distance and the deflection angle of the transceiver arrays.To achieve an ideal arrangement,two methods of the single-array translation alignment and the dual-array deflection alignment are developed based on the least standard deviation of the OAM spectrum(SD-OAM).By decreasing the SD-OAM towards zero using transceiver arrays of 16 transmitters and 16 receivers,accurate beam alignments are accomplished by multiple adjustments in three dimensions.The proposed method is also demonstrated by experimental measurements of the OAM dispersion and the SD-OAM for misaligned beams.The results demonstrate the feasibility of the rapid beam alignment based on the OAM spectrum decomposition by using simplified transceiver ring-arrays,and suggest more application potentials for acoustic communications.
作者
Gepu Guo
Xinjia Li
Qingdong Wang
Yuzhi Li
Qingyu Ma
Juan Tu
Dong Zhang
郭各朴;李昕珈;王青东;李禹志;马青玉;屠娟;章东(School of Computer and Electronic Information,Nanjing Normal University,Nanjing 210023,China;Haiying Enterprise Group Co.,Ltd.,Wuxi 214061,China;College of Ocean Science and Engineering,Shandong University of Science and Technology,Qingdao 266590,China;Institute of Acoustics,Nanjing University,Nanjing 210093,China)
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.11934009,11974187,and 12174198)
