a rectenna designed for wireless power transfer at 900 MHz focuses on conjugate impedance matching and image impedance matching for improved efficiency. To do them, a voltage doubler rectifier circuit (VD) and a planar monopole antenna (PMA) were engineered with the same pure resistance value and integrated into the rectenna. The input impedance of the VD with 30 Ω load resistance indicated a pure resistance of approximately 73 Ω. This value closely matches the input impedance of a dipole antenna operating as a pure resistor. Since the prototype rectifier circuit is unbalanced, the authors constructed a PMA, an unbalanced antenna similar to a dipole antenna, on a double-sided circuit board. In this setup, a microstrip line was created by extending the radiating element, achieving the impedance matchings. Measurements indicated a voltage standing wave ratio of approximately 1.03. A rectenna efficiency of 37.4% was observed for a transmission distance of 50 cm. The rectification efficiency of the VD is nearly 0% when the input power is less than — 20 dBm, and the received power of the PMA is less than — 20 dBm when the transmission distance is 60 cm or more. It is predicted that the rectenna efficiency will be 0% when the transmission distance is 60 cm or more. However, the rectenna efficiency was 24.6% when the transmission distance was 60 cm. This over 20% improvement is due to the connection between the PMA and the VD using pure resistance.
{"title":"A prototype of a 900 MHz band integrated rectenna by using a planar monopole antenna with feeder","authors":"N. Nakashima;T. Sumiyoshi","doi":"10.1029/2024RS008022","DOIUrl":"https://doi.org/10.1029/2024RS008022","url":null,"abstract":"a rectenna designed for wireless power transfer at 900 MHz focuses on conjugate impedance matching and image impedance matching for improved efficiency. To do them, a voltage doubler rectifier circuit (VD) and a planar monopole antenna (PMA) were engineered with the same pure resistance value and integrated into the rectenna. The input impedance of the VD with 30 Ω load resistance indicated a pure resistance of approximately 73 Ω. This value closely matches the input impedance of a dipole antenna operating as a pure resistor. Since the prototype rectifier circuit is unbalanced, the authors constructed a PMA, an unbalanced antenna similar to a dipole antenna, on a double-sided circuit board. In this setup, a microstrip line was created by extending the radiating element, achieving the impedance matchings. Measurements indicated a voltage standing wave ratio of approximately 1.03. A rectenna efficiency of 37.4% was observed for a transmission distance of 50 cm. The rectification efficiency of the VD is nearly 0% when the input power is less than — 20 dBm, and the received power of the PMA is less than — 20 dBm when the transmission distance is 60 cm or more. It is predicted that the rectenna efficiency will be 0% when the transmission distance is 60 cm or more. However, the rectenna efficiency was 24.6% when the transmission distance was 60 cm. This over 20% improvement is due to the connection between the PMA and the VD using pure resistance.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142130258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sukanth Karapakula;Christiaan Brinkerink;Antonio Vecchio;Hamid R. Pourshaghaghi;Peter Dolron;Roel Jordans;Eric Bertels;Gerard Aalbers;Mark Ruiter;Albert J. Boonstra;Mark Bentum;David Prinsloo;Michel Arts;Jeanette Bast;Sieds Damstra;Albert van Duin;Nico Ebbendorf;Hans van der Marel;Juergen Morawietz;Roel Witvers;Wietse Poiesz;Rico van Dongen;Baptiste Cecconi;Philippe Zarka;Moustapha Dekkali;Linjie Chen;Mingyuan Wang;Mo Zhang;Maohai Huang;Yihua Yan;Liang Dong;Baolin Tan;Lihua Zhang;Liang Xiong;Ji Sun;Hongbo Zhang;Jinsong Ping;Marc Klein Wolt;Heino Falcke
The Netherlands-China Low-Frequency Explorer (NCLE) (Boonstra et al., 2017, https://www. ursi.org/proceedings/procGA17/papers/Paper_J19-2(1603).pdf; Chen et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AAS...23610203C/abstract) is a radio instrument for astrophysical studies in the low-frequency range (80 kHz-80 MHz). As a technology demonstrator, NCLE shall inform the design of future radio receivers that aim at low-frequency radio astronomy. NCLE can make observations at very high spectral resolution (<1 kHz) and generate radio sky maps at an angular resolution of ≈1.5 radians. NCLE uses three monopole antennas, each 5 m long, and three identical analog signal chains to process the signal from each antenna. A single digital receiver samples the signal and calculates the auto-correlated and cross-correlated spectra. The instrument's analog and digital signal chains are extensively configurable. They can be fine-tuned to produce broadband spectra covering the instrument's complete operating frequency range or sub-bands. NCLE was developed within a veryshort timescale of 2 years, and currently, it is on board Queqiao, the relay spacecraft of the Chang'e-4 mission, in a halo orbit around the Earth-Moon L2 point. This paper outlines the science cases, instrument architecture with focus on the signal chain, and discusses the laboratory measurements during the pre-launch phase.
{"title":"Architecture design and ground performance of Netherlands-China low-frequency explorer","authors":"Sukanth Karapakula;Christiaan Brinkerink;Antonio Vecchio;Hamid R. Pourshaghaghi;Peter Dolron;Roel Jordans;Eric Bertels;Gerard Aalbers;Mark Ruiter;Albert J. Boonstra;Mark Bentum;David Prinsloo;Michel Arts;Jeanette Bast;Sieds Damstra;Albert van Duin;Nico Ebbendorf;Hans van der Marel;Juergen Morawietz;Roel Witvers;Wietse Poiesz;Rico van Dongen;Baptiste Cecconi;Philippe Zarka;Moustapha Dekkali;Linjie Chen;Mingyuan Wang;Mo Zhang;Maohai Huang;Yihua Yan;Liang Dong;Baolin Tan;Lihua Zhang;Liang Xiong;Ji Sun;Hongbo Zhang;Jinsong Ping;Marc Klein Wolt;Heino Falcke","doi":"10.1029/2023RS007906","DOIUrl":"https://doi.org/10.1029/2023RS007906","url":null,"abstract":"The Netherlands-China Low-Frequency Explorer (NCLE) (Boonstra et al., 2017, https://www. ursi.org/proceedings/procGA17/papers/Paper_J19-2(1603).pdf; Chen et al., 2020, https://ui.adsabs.harvard.edu/abs/2020AAS...23610203C/abstract) is a radio instrument for astrophysical studies in the low-frequency range (80 kHz-80 MHz). As a technology demonstrator, NCLE shall inform the design of future radio receivers that aim at low-frequency radio astronomy. NCLE can make observations at very high spectral resolution (<1 kHz) and generate radio sky maps at an angular resolution of ≈1.5 radians. NCLE uses three monopole antennas, each 5 m long, and three identical analog signal chains to process the signal from each antenna. A single digital receiver samples the signal and calculates the auto-correlated and cross-correlated spectra. The instrument's analog and digital signal chains are extensively configurable. They can be fine-tuned to produce broadband spectra covering the instrument's complete operating frequency range or sub-bands. NCLE was developed within a veryshort timescale of 2 years, and currently, it is on board Queqiao, the relay spacecraft of the Chang'e-4 mission, in a halo orbit around the Earth-Moon L2 point. This paper outlines the science cases, instrument architecture with focus on the signal chain, and discusses the laboratory measurements during the pre-launch phase.","PeriodicalId":49638,"journal":{"name":"Radio Science","volume":null,"pages":null},"PeriodicalIF":1.6,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142130281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, a wideband circularly polarized (CP) H-plane horn antenna based on Gap Waveguide (GW) technology in K-band is presented. The proposed antenna consists of two unconnected metal planes. To produce broadband CP radiation, two main methods are utilized. First, two antipodal tapered plates (ATPs) are added in front of the horn. The ATPs are carefully designed for dissimilar polarization orientations. By this technique, the orthogonal electric fields can be prepared. Then, by embedding three metal square pins near the center of the aperture in both inner plates, the impedance bandwidth (BW) and BW of CP radiation of the proposed horn is entirely improved. Its BW for target |S 11