The influence of the longitudinal acceleration and the angular acceleration of detecting target based on vortex electromagnetic waves in keyhole space are analyzed.The spectrum spreads of different orbital angular mom...The influence of the longitudinal acceleration and the angular acceleration of detecting target based on vortex electromagnetic waves in keyhole space are analyzed.The spectrum spreads of different orbital angular momentum(OAM)modes in different non-line-of-sight situations are simulated.The errors of target accelerations in detection are calculated and compared based on the OAM spectra spreading by using two combinations of composite OAM modes in the keyhole space.According to the research,the effects about spectrum spreads of higher OAM modes are more obvious.The error in detection is mainly affected by OAM spectrum spreading,which can be reduced by reasonably using different combinations of OAM modes in different practical situations.The above results provide a reference idea for investigating keyhole effect when vortex electromagnetic wave is used to detect accelerations.展开更多
In this paper,we combine the circular polarization technology and orbital angular momentum(OAM)into the array antenna design for the first time,achieve free switch of the different topological charges in the array by ...In this paper,we combine the circular polarization technology and orbital angular momentum(OAM)into the array antenna design for the first time,achieve free switch of the different topological charges in the array by using high-speed radio frequency(RF)switch technology.We arrange microstrip patch antenna elements equidistantly along the circumference to form eight elements multi-modal OAM vortex electromagnetic wave microstrip array antenna.It can generate elec-tromagnetic waves with dual characteristics of circular polarization and multi-modal vortex OAM(where OAM mode values are l=0,l=±1,l=±2,l=±3).Through simulation,we find mutual coupling between the radiating elements is small relatively,and increasing the number of array elements can not only improve the beam quality,but also generate electromagnetic waves with a higher order of OAM modes.Antenna model can meet the basic demands of ordinary array antenna,and also confirm the practicality of this circular polarized microstrip antenna array model.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11804073 and 61775050).
文摘The influence of the longitudinal acceleration and the angular acceleration of detecting target based on vortex electromagnetic waves in keyhole space are analyzed.The spectrum spreads of different orbital angular momentum(OAM)modes in different non-line-of-sight situations are simulated.The errors of target accelerations in detection are calculated and compared based on the OAM spectra spreading by using two combinations of composite OAM modes in the keyhole space.According to the research,the effects about spectrum spreads of higher OAM modes are more obvious.The error in detection is mainly affected by OAM spectrum spreading,which can be reduced by reasonably using different combinations of OAM modes in different practical situations.The above results provide a reference idea for investigating keyhole effect when vortex electromagnetic wave is used to detect accelerations.
基金supported in part by the Nation Natural Science Foundation of China(No.61561039)the Nation Natural Science Foundation of Ningxia Province(No.NZ17041).
文摘In this paper,we combine the circular polarization technology and orbital angular momentum(OAM)into the array antenna design for the first time,achieve free switch of the different topological charges in the array by using high-speed radio frequency(RF)switch technology.We arrange microstrip patch antenna elements equidistantly along the circumference to form eight elements multi-modal OAM vortex electromagnetic wave microstrip array antenna.It can generate elec-tromagnetic waves with dual characteristics of circular polarization and multi-modal vortex OAM(where OAM mode values are l=0,l=±1,l=±2,l=±3).Through simulation,we find mutual coupling between the radiating elements is small relatively,and increasing the number of array elements can not only improve the beam quality,but also generate electromagnetic waves with a higher order of OAM modes.Antenna model can meet the basic demands of ordinary array antenna,and also confirm the practicality of this circular polarized microstrip antenna array model.