A low-profile dual-broadband dual-circularly-polarized(dual-CP)reflectarray(RA)is proposed and demonstrated,supporting independent beamforming for right-/left-handed CP waves at both K-band and Ka-band.Such functional...A low-profile dual-broadband dual-circularly-polarized(dual-CP)reflectarray(RA)is proposed and demonstrated,supporting independent beamforming for right-/left-handed CP waves at both K-band and Ka-band.Such functionality is achieved by incorporating multi-layered phase shifting elements individually operating in the K-and Ka-band,which are then interleaved in a shared aperture,resulting in a cell thickness of only about O.1az.By rotating the designed K-and Ka-band elements around their own geometrical centers,the dual-CP waves in each band can be modulated separately.To reduce the overall profile,planar K-/Ka-band dual-CP feeds with a broad band are designed based on the magnetoelectric dipoles and multi-branch hybrid couplers.The planar feeds achieve bandwidths of about 32%and 26%at K-and Ka-band respectively with reflection magnitudes below-13 dB,an axial ratio smaller than 2 dB,and a gain variation of less than 1 dB.A proof-of-concept dual-band dual-CP RA integrated with the planar feeds is fabricated and characterized which is capable of generating asymmetrically distributed dual-band dual-CP beams.The measured peak gain values of the beams are around 24.3 and 27.3 dBic,with joint gain variation<1 dB and axial ratio<2 dB bandwidths wider than 20.6%and 14.6%at the lower and higher bands,respectively.The demonstrated dual-broadband dual-CP RA with four degrees of freedom of beamforming could be a promising candidate for space and satellite communications.展开更多
基金supported by the National Natural Science Foundation of China(Nos.62122019,62293492,and 61901106)the ZTE Corporation and the State Key Laboratory of Mobile Network and Mobile Multimedia Technology,and the Fundamental Research Funds for Central Universities,China(No.2242022k60008)。
文摘A low-profile dual-broadband dual-circularly-polarized(dual-CP)reflectarray(RA)is proposed and demonstrated,supporting independent beamforming for right-/left-handed CP waves at both K-band and Ka-band.Such functionality is achieved by incorporating multi-layered phase shifting elements individually operating in the K-and Ka-band,which are then interleaved in a shared aperture,resulting in a cell thickness of only about O.1az.By rotating the designed K-and Ka-band elements around their own geometrical centers,the dual-CP waves in each band can be modulated separately.To reduce the overall profile,planar K-/Ka-band dual-CP feeds with a broad band are designed based on the magnetoelectric dipoles and multi-branch hybrid couplers.The planar feeds achieve bandwidths of about 32%and 26%at K-and Ka-band respectively with reflection magnitudes below-13 dB,an axial ratio smaller than 2 dB,and a gain variation of less than 1 dB.A proof-of-concept dual-band dual-CP RA integrated with the planar feeds is fabricated and characterized which is capable of generating asymmetrically distributed dual-band dual-CP beams.The measured peak gain values of the beams are around 24.3 and 27.3 dBic,with joint gain variation<1 dB and axial ratio<2 dB bandwidths wider than 20.6%and 14.6%at the lower and higher bands,respectively.The demonstrated dual-broadband dual-CP RA with four degrees of freedom of beamforming could be a promising candidate for space and satellite communications.
