Energy-saving buildings(ESBs)are an emerging green technology that can significantly reduce building-associated cooling and heating energy consumption,catering to the desire for carbon neutrality and sustainable devel...Energy-saving buildings(ESBs)are an emerging green technology that can significantly reduce building-associated cooling and heating energy consumption,catering to the desire for carbon neutrality and sustainable development of society.Smart photovoltaic windows(SPWs)offer a promising platform for designing ESBs because they present the capability to regulate and harness solar energy.With frequent outbreaks of extreme weather all over the world,the achievement of exceptional energy-saving effect under different weather conditions is an inevitable trend for the development of ESBs but is hardly achieved via existing SPWs.Here,we substantially reduce the driving voltage of polymerdispersed liquid crystals(PDLCs)by 28.1%via molecular engineering while maintaining their high solar transmittance(T_(sol)=83.8%,transparent state)and solar modulating ability(ΔT_(sol)=80.5%).By the assembly of perovskite solar cell and a broadband thermal-managing unit encompassing the electrical-responsive PDLCs,transparent high-emissivity SiO_(2) passive radiation-cooling,and Ag low-emissivity layers possesses,we present a tri-band regulation and split-type SPW possessing superb energy-saving effect in all-season.The perovskite solar cell can produce the electric power to stimulate the electrical-responsive behavior of the PDLCs,endowing the SPWs zero-energy input solar energy regulating characteristic,and compensate the daily energy consumption needed for ESBs.Moreover,the scalable manufacturing technology holds a great potential for the real-world applications.展开更多
We designed and constructed a novel,compact tri-band monopole antenna for intelligent devices.Multiband behavior was achieved by placing inverted-L shaped stubs of various lengths in a triangular monopole antenna fed ...We designed and constructed a novel,compact tri-band monopole antenna for intelligent devices.Multiband behavior was achieved by placing inverted-L shaped stubs of various lengths in a triangular monopole antenna fed by a coplanar waveguide.The resonance frequency of each band can be controlled by varying the length of the corresponding stub.Three bands,at 2.4(2.37-2.51),3.5(3.34-3.71),and 5.5(4.6-6.4)GHz,were easily obtained using three stubs of different lengths.For miniaturization,a portion of the longest stub(at 2.4 GHz)was printed on the opposite side of the substrate,and connected to the main stub via a shorting pin.To validate the concept,the antenna was fabricated on a low-cost 1.6-mm-thick FR-4 substrate with dimensions of 20×15×1.6 mm^(3).The antenna exhibited a moderate average gain of 2.9 dBi with an omnidirectional radiations over the bandwidths required for RFID,Bluetooth,ISM,WiMAX,andWLAN-band applications.These features make the antenna suitable for compact smart devices.展开更多
<div style="text-align:justify;"> A novel method for tri-band microstrip array antenna with improvement in the bandwidth by incorporating wide slots and additional resonators which is gap-coupled to th...<div style="text-align:justify;"> A novel method for tri-band microstrip array antenna with improvement in the bandwidth by incorporating wide slots and additional resonators which is gap-coupled to the non-radiating edges of a radiating element is presented. The experimental results show that two element slot-loaded gap-coupled microstrip array antenna gives a ?10 dB return loss band-width for three bands. The design specifications, radiation patterns and gain of the proposed antennas are presented and described. </div>展开更多
This paper presents the tri-band slot loaded patch antenna for mobile communication. The antenna consists of parallel slots loaded circular disk with defected ground structure antenna (DGS). The antenna without DGS, a...This paper presents the tri-band slot loaded patch antenna for mobile communication. The antenna consists of parallel slots loaded circular disk with defected ground structure antenna (DGS). The antenna without DGS, acts like wide band antenna and bandwidth is 34.45% (3.47 - 4.92 GHz) with maximum gain of 4.97 dBi, which can be used in WiMax application. This structure has the following advantages: 1) co-axial feeding technique, which is very simple as compared to other feeding technique, 2) simple and cost effective and 3) it is more efficient than the antenna without DGS. This antenna has been analyzed using IE3D simulation software.展开更多
传统天线优化方法通常依靠高频结构仿真(high frequency structure simulator,HFSS)自带的参数优化器,不仅工作量大,而且效率低下,难以在短时间内获得最优设计方案。为了解决这个问题,提出了一种改进的萤火虫算法。在种群分布方面,引入...传统天线优化方法通常依靠高频结构仿真(high frequency structure simulator,HFSS)自带的参数优化器,不仅工作量大,而且效率低下,难以在短时间内获得最优设计方案。为了解决这个问题,提出了一种改进的萤火虫算法。在种群分布方面,引入了Logistic混沌映射初始化种群。为了平衡算法全局探索与局部开发能力,引入了参数动态自适应机制,采用步长因子的指数递减策略与光吸收系数的递增策略,二者相互协同,解决了传统萤火虫算法参数敏感的问题。对于每次迭代中适应度值较差的个体,采用莱维飞行策略,帮助其跳出局部最优。上述改进后的萤火虫算法经测试后,展现出良好的性能。将改进后的算法应用于一种三频段天线的设计与优化中,结果表明,经算法优化后天线的回波损耗最低达到-37.5 dB,低频带和高频带的带宽提高至0.4 GHz和0.93 GHz,相比于原来分别提升了37%和36%,符合预期要求。展开更多
A novel tri-band bandpass filter （BPF） is proposed by using cross-coupled stepped impedance resonators （SIRs）, which can operate at 2.4 GHz, 3.5 GHz and 5.25 GHz respectively. In engineering application, it is sui...A novel tri-band bandpass filter （BPF） is proposed by using cross-coupled stepped impedance resonators （SIRs）, which can operate at 2.4 GHz, 3.5 GHz and 5.25 GHz respectively. In engineering application, it is suitable for wireless local area network （WLAN） and worldwide interoperability for microwave access （WiMAX）. In addition, the passband of this filter can be easily controlled by changing the electrical parameters of the resonators. So it is helpful to the selection of passband in engineering applications. For in-depth analysis, the equivalent circuit of the filter is also proposed. At last, it shows that the measured results agree well with the simulated results. The insertion loss of the filter within each passband is less than 1.9 dB, meanwhile two transmission zeros are obtained which can be able to meet the engineering requirements.展开更多
基金supported by Natural Science Foundation of China(Grant No.52372076,52073081,52203322,5252200843)Ministry of Science and Technology of the People’s Republic of China(2023YFB3812800)Fundamental Research Funds for the Central Universities(FRF-TP-25-073)。
文摘Energy-saving buildings(ESBs)are an emerging green technology that can significantly reduce building-associated cooling and heating energy consumption,catering to the desire for carbon neutrality and sustainable development of society.Smart photovoltaic windows(SPWs)offer a promising platform for designing ESBs because they present the capability to regulate and harness solar energy.With frequent outbreaks of extreme weather all over the world,the achievement of exceptional energy-saving effect under different weather conditions is an inevitable trend for the development of ESBs but is hardly achieved via existing SPWs.Here,we substantially reduce the driving voltage of polymerdispersed liquid crystals(PDLCs)by 28.1%via molecular engineering while maintaining their high solar transmittance(T_(sol)=83.8%,transparent state)and solar modulating ability(ΔT_(sol)=80.5%).By the assembly of perovskite solar cell and a broadband thermal-managing unit encompassing the electrical-responsive PDLCs,transparent high-emissivity SiO_(2) passive radiation-cooling,and Ag low-emissivity layers possesses,we present a tri-band regulation and split-type SPW possessing superb energy-saving effect in all-season.The perovskite solar cell can produce the electric power to stimulate the electrical-responsive behavior of the PDLCs,endowing the SPWs zero-energy input solar energy regulating characteristic,and compensate the daily energy consumption needed for ESBs.Moreover,the scalable manufacturing technology holds a great potential for the real-world applications.
基金This work was supported by the ICT R&D program of MSIT/IITP,[2019-0-00102,A Study on Public Health and Safety in a Complex EMF Environment].This work was also supported by the National Radio ResearchAgency,[Rapid measurement system for new technologyantenna].
文摘We designed and constructed a novel,compact tri-band monopole antenna for intelligent devices.Multiband behavior was achieved by placing inverted-L shaped stubs of various lengths in a triangular monopole antenna fed by a coplanar waveguide.The resonance frequency of each band can be controlled by varying the length of the corresponding stub.Three bands,at 2.4(2.37-2.51),3.5(3.34-3.71),and 5.5(4.6-6.4)GHz,were easily obtained using three stubs of different lengths.For miniaturization,a portion of the longest stub(at 2.4 GHz)was printed on the opposite side of the substrate,and connected to the main stub via a shorting pin.To validate the concept,the antenna was fabricated on a low-cost 1.6-mm-thick FR-4 substrate with dimensions of 20×15×1.6 mm^(3).The antenna exhibited a moderate average gain of 2.9 dBi with an omnidirectional radiations over the bandwidths required for RFID,Bluetooth,ISM,WiMAX,andWLAN-band applications.These features make the antenna suitable for compact smart devices.
文摘<div style="text-align:justify;"> A novel method for tri-band microstrip array antenna with improvement in the bandwidth by incorporating wide slots and additional resonators which is gap-coupled to the non-radiating edges of a radiating element is presented. The experimental results show that two element slot-loaded gap-coupled microstrip array antenna gives a ?10 dB return loss band-width for three bands. The design specifications, radiation patterns and gain of the proposed antennas are presented and described. </div>
文摘This paper presents the tri-band slot loaded patch antenna for mobile communication. The antenna consists of parallel slots loaded circular disk with defected ground structure antenna (DGS). The antenna without DGS, acts like wide band antenna and bandwidth is 34.45% (3.47 - 4.92 GHz) with maximum gain of 4.97 dBi, which can be used in WiMax application. This structure has the following advantages: 1) co-axial feeding technique, which is very simple as compared to other feeding technique, 2) simple and cost effective and 3) it is more efficient than the antenna without DGS. This antenna has been analyzed using IE3D simulation software.
基金supported by the National Natural Science Foundation of China (61571063, 61202399, 61501100)
文摘A novel tri-band bandpass filter （BPF） is proposed by using cross-coupled stepped impedance resonators （SIRs）, which can operate at 2.4 GHz, 3.5 GHz and 5.25 GHz respectively. In engineering application, it is suitable for wireless local area network （WLAN） and worldwide interoperability for microwave access （WiMAX）. In addition, the passband of this filter can be easily controlled by changing the electrical parameters of the resonators. So it is helpful to the selection of passband in engineering applications. For in-depth analysis, the equivalent circuit of the filter is also proposed. At last, it shows that the measured results agree well with the simulated results. The insertion loss of the filter within each passband is less than 1.9 dB, meanwhile two transmission zeros are obtained which can be able to meet the engineering requirements.
