A novel low profile multiband rectenna was proposed for harvesting the 2 nd generation(2 G), the 3 rd generation(3 G), the 4 th generation(4 G), wireless local area networks(WLANs) etc., electromagnetic wave energy. T...A novel low profile multiband rectenna was proposed for harvesting the 2 nd generation(2 G), the 3 rd generation(3 G), the 4 th generation(4 G), wireless local area networks(WLANs) etc., electromagnetic wave energy. The proposed rectenna consists of a novel multiband antenna and a rectifier. The multiband antenna includes a radiating element on one side of a single layer dielectric substrate and a feeding spiral balun on the other side of the substrate. A conductive via is connected between the balun and the radiating element. In the radiating element, a deformed dipole structure is connected with an equiangular spiral slot structure and is used to generate a low frequency radiation around 900 MHz. The multiband antenna can work simultaneously at 0.869 GHz^0.948 GHz, 1.432 GHz^2.173 GHz, and 2.273 GHz^2.465 GHz with its peak gains of 7.1 dBi at 903 MHz, 4.1 dBi at 1 800 MHz, 5.2 dBi at 2 430 MHz. The radio frequency to direct current(RF-to-DC) conversion efficiencies of the rectifier are 58%~62% at these three frequencies for an input power of 0 dBm. The overall measurement results validate that the rectenna suits for energy harvesting and exhibits approximate maximum efficiencies of 58% at 0.9 GHz, 56% at 1.8 GHz, and 55% at 2.4 GHz with a low incident power density of 8 μW/cm^2.展开更多
This paper describes the design and fabrication of superconducting hot electron bolometer (HEB) mixer based on ultra-thin superconducting NbN films. The high quality films were epitaxially grown on high resistance Si ...This paper describes the design and fabrication of superconducting hot electron bolometer (HEB) mixer based on ultra-thin superconducting NbN films. The high quality films were epitaxially grown on high resistance Si substrates. The device was fabricated by magnetron sputtering, electron beam lithography (EBL), reactive ion etching (RIE), lithography, and so on. The device's resistance-tempera-ture (R-T) curves and current-voltage (I-V) curves were studied. The results of THz response of the device are presented. Y-factor technique was used to measure the device's noise temperature. When the device was irradiated with a laser radiation of 2.5 THz, the obtained lowest noise temperature of the device was 2213 K.展开更多
基金supported by the Open Fund Project of Engineering Research and Development Center of Nanjing College of Information Technology (KF20160103)the Jiangsu Province Qing Lan Project,the Jiangsu Province 333 Project (BRA2017343)+2 种基金the Jiangsu Province University Student Innovation and Entrepreneurship Training Program (2018)the Nanjing Qixia District Industry-University-Research Cooperation Project (GC201804)the National Natural Science Foundation of China (61671232)
文摘A novel low profile multiband rectenna was proposed for harvesting the 2 nd generation(2 G), the 3 rd generation(3 G), the 4 th generation(4 G), wireless local area networks(WLANs) etc., electromagnetic wave energy. The proposed rectenna consists of a novel multiband antenna and a rectifier. The multiband antenna includes a radiating element on one side of a single layer dielectric substrate and a feeding spiral balun on the other side of the substrate. A conductive via is connected between the balun and the radiating element. In the radiating element, a deformed dipole structure is connected with an equiangular spiral slot structure and is used to generate a low frequency radiation around 900 MHz. The multiband antenna can work simultaneously at 0.869 GHz^0.948 GHz, 1.432 GHz^2.173 GHz, and 2.273 GHz^2.465 GHz with its peak gains of 7.1 dBi at 903 MHz, 4.1 dBi at 1 800 MHz, 5.2 dBi at 2 430 MHz. The radio frequency to direct current(RF-to-DC) conversion efficiencies of the rectifier are 58%~62% at these three frequencies for an input power of 0 dBm. The overall measurement results validate that the rectenna suits for energy harvesting and exhibits approximate maximum efficiencies of 58% at 0.9 GHz, 56% at 1.8 GHz, and 55% at 2.4 GHz with a low incident power density of 8 μW/cm^2.
基金Supported by the National Basic Research Program of China(Grant Nos.2006CB601006,2007CB310404)High-Tech Research and Development Pro-gram of China(Grant No.2006AA12Z120)
文摘This paper describes the design and fabrication of superconducting hot electron bolometer (HEB) mixer based on ultra-thin superconducting NbN films. The high quality films were epitaxially grown on high resistance Si substrates. The device was fabricated by magnetron sputtering, electron beam lithography (EBL), reactive ion etching (RIE), lithography, and so on. The device's resistance-tempera-ture (R-T) curves and current-voltage (I-V) curves were studied. The results of THz response of the device are presented. Y-factor technique was used to measure the device's noise temperature. When the device was irradiated with a laser radiation of 2.5 THz, the obtained lowest noise temperature of the device was 2213 K.
