A bandwidth-enhanced dual-polarized antenna is proposed for 2/3/4/5G applications,which is composed of distributed parasitic elements(DPEs),a main radiator,two improved broadband integrated baluns and a reflector.Firs...A bandwidth-enhanced dual-polarized antenna is proposed for 2/3/4/5G applications,which is composed of distributed parasitic elements(DPEs),a main radiator,two improved broadband integrated baluns and a reflector.First,a novel tooth-shape shorted slot line in the improved broadband integrated balun is analyzed to adjust the input impedance of the antenna.Then,DPEs with 2×2 circular plates loading over the main radiator are proposed to improve broadband impedance matching and radiation pattern.By utilizing impedance compensation of the tooth-shaped shorted slot line and the electromagnetic induction of the DPEs,the antenna achieves an enhanced impedance bandwidth and a stable radiation pattern.To verify these ideas,the bandwidth-enhanced dual-polarized antenna was fabricated and measured.The experimental results indicate that the proposed antenna achieves an operating bandwidth of 72.2%(1.69 to 3.60 GHz)with a return loss(RL)less than-15 dB and a port-to-port isolation(ISO)larger than 30 dB.The antenna obtains a half-power beamwidth(HPBW)within(66±5)°and a gain within(9.0±0.6)dBi in the 2/3/4G bands,and an HPBW within(61.5±2.5)°and a gain within(9.8±0.3)dBi in the 5G band.Across the whole band,the cross-polarization discrimination(XPD)and the front-to-back ratio are both larger than 20 dB.展开更多
The Middle Jurassic Daohugou Biota has yielded very rich fossil plants, vertebrates, and inver tebrates. The particularly famous fossil insects are represented by at least 24 orders, revealing one of the most diverse ...The Middle Jurassic Daohugou Biota has yielded very rich fossil plants, vertebrates, and inver tebrates. The particularly famous fossil insects are represented by at least 24 orders, revealing one of the most diverse Mesozoic insect communities. Among them, the occurrence of Emhioptera, Mantophasma- todea, and Siphonaptera increased respectively as supported by fossil evidence from Daohugou. Moreover, the early co-evolution of ectoparasites and their hosts may be analyzed by the presence of various giant fleas and the co-occurred potential hosts such as mammals, feather dinosaurs, and pterosaurs from Daohugou.展开更多
基金The National Natural Science Foundation of China(No.61471117).
文摘A bandwidth-enhanced dual-polarized antenna is proposed for 2/3/4/5G applications,which is composed of distributed parasitic elements(DPEs),a main radiator,two improved broadband integrated baluns and a reflector.First,a novel tooth-shape shorted slot line in the improved broadband integrated balun is analyzed to adjust the input impedance of the antenna.Then,DPEs with 2×2 circular plates loading over the main radiator are proposed to improve broadband impedance matching and radiation pattern.By utilizing impedance compensation of the tooth-shaped shorted slot line and the electromagnetic induction of the DPEs,the antenna achieves an enhanced impedance bandwidth and a stable radiation pattern.To verify these ideas,the bandwidth-enhanced dual-polarized antenna was fabricated and measured.The experimental results indicate that the proposed antenna achieves an operating bandwidth of 72.2%(1.69 to 3.60 GHz)with a return loss(RL)less than-15 dB and a port-to-port isolation(ISO)larger than 30 dB.The antenna obtains a half-power beamwidth(HPBW)within(66±5)°and a gain within(9.0±0.6)dBi in the 2/3/4G bands,and an HPBW within(61.5±2.5)°and a gain within(9.8±0.3)dBi in the 5G band.Across the whole band,the cross-polarization discrimination(XPD)and the front-to-back ratio are both larger than 20 dB.
基金supported by the National Basic Research Program of China(2012CB821903)Outstanding Youth Foundation of Jiangsu Province(BK 2012049)the National Natural Science Foundation of China(91114201)
文摘The Middle Jurassic Daohugou Biota has yielded very rich fossil plants, vertebrates, and inver tebrates. The particularly famous fossil insects are represented by at least 24 orders, revealing one of the most diverse Mesozoic insect communities. Among them, the occurrence of Emhioptera, Mantophasma- todea, and Siphonaptera increased respectively as supported by fossil evidence from Daohugou. Moreover, the early co-evolution of ectoparasites and their hosts may be analyzed by the presence of various giant fleas and the co-occurred potential hosts such as mammals, feather dinosaurs, and pterosaurs from Daohugou.
