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IEEE Antennas and Wireless Propagation Letters, 2011
Conventional spiral antennas radiate either a left-handed circularly polarized (CP) wave or a right-handed CP wave in a specific direction (single CP radiation). This letter presents a novel spiral antenna, designated as the metamaterial spiral, which radiates a dual CP wave.
H. Nakano +3 more
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Conventional spiral antennas radiate either a left-handed circularly polarized (CP) wave or a right-handed CP wave in a specific direction (single CP radiation). This letter presents a novel spiral antenna, designated as the metamaterial spiral, which radiates a dual CP wave.
H. Nakano +3 more
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Low-Dispersion Spiral Antennas
IEEE Transactions on Antennas and Propagation, 2012A two-arm power spiral antenna with inherently low dispersion is proposed. Analytical, computational, and experimental steps are taken to demonstrate its superior time domain performance. When compared with conventional Archimedean and equiangular spirals, up to 40% improved fidelity factor and pulse compression are achieved.
M. A. Elmansouri, D. S. Filipovic
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IEE Proceedings H Microwaves, Antennas and Propagation, 1991
Two types of dual-spiral slot antennas characterised by their simple feed are studied; one is a bidirectional radiation type (Bi-DSS) and the other is a unidirectional type (Uni-DSS). The radiation characteristics of the Bi-DSS are evaluated using the numerically determined magnetic current distribution.
K. Hirose, H. Nakano
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Two types of dual-spiral slot antennas characterised by their simple feed are studied; one is a bidirectional radiation type (Bi-DSS) and the other is a unidirectional type (Uni-DSS). The radiation characteristics of the Bi-DSS are evaluated using the numerically determined magnetic current distribution.
K. Hirose, H. Nakano
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1979 9th European Microwave Conference, 1979
The cavity backed spiral antenna with a square configuration is described. It is shown that with continual development and an invention of a unique design of cavity the aperture of this type of antenna is reduced to approximately 0.1? square at its lowest operating frequency.
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The cavity backed spiral antenna with a square configuration is described. It is shown that with continual development and an invention of a unique design of cavity the aperture of this type of antenna is reduced to approximately 0.1? square at its lowest operating frequency.
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2018 14th International Conference on Advanced Trends in Radioelecrtronics, Telecommunications and Computer Engineering (TCSET), 2018
The main results of numerical simulation of the characteristics of a spiral antenna with small number of turns and peripheral feeding by a coplanar waveguide are presented. The features of this antenna are: its wideband parameters, both in terms of input impedance and directional characteristics, as well as small geometric dimensions.
Serhii Siden +2 more
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The main results of numerical simulation of the characteristics of a spiral antenna with small number of turns and peripheral feeding by a coplanar waveguide are presented. The features of this antenna are: its wideband parameters, both in terms of input impedance and directional characteristics, as well as small geometric dimensions.
Serhii Siden +2 more
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1998 Symposium on Antenna Technology and Applied Electromagnetics, 1998
Recently, we have analyzed a spirally-wound antenna [1][2] proposed by Fenwick using the method of moments. The analysis shows that the. input impedance is very low (less than 4 ohms). It is also shown that the frequency bandwidth is very narrow (less than 0.2% for a criterion of VSWR = 2 to an input resistance at resonance).
H. Nakano +4 more
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Recently, we have analyzed a spirally-wound antenna [1][2] proposed by Fenwick using the method of moments. The analysis shows that the. input impedance is very low (less than 4 ohms). It is also shown that the frequency bandwidth is very narrow (less than 0.2% for a criterion of VSWR = 2 to an input resistance at resonance).
H. Nakano +4 more
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UWB filter-antenna using Spiral Resonator
2010 Loughborough Antennas & Propagation Conference, 2010This paper presents simple and low cost implementations of very wideband antennas using Spiral Resonator (SR) to perform band-rejection filtering within the band. Details on SR design are first given and filter design is then applied on a UWB antenna to filter the WLAN band.
Le Fur, Gwenn, Sharaiha, Ala
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IEE Proceedings F Communications, Radar and Signal Processing, 1985
The reason for the popularity of the cavity-backed spiral antenna in ESM systems is discussed, together with the surprising lack of supporting analysis and detailed understanding of its operation. In the absence of any published mathematical analysis of the complete antenna, the function and principle of operation of the three main antenna components ...
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The reason for the popularity of the cavity-backed spiral antenna in ESM systems is discussed, together with the surprising lack of supporting analysis and detailed understanding of its operation. In the absence of any published mathematical analysis of the complete antenna, the function and principle of operation of the three main antenna components ...
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Stripline-Fed Archimedean Spiral Antenna
IEEE Antennas and Wireless Propagation Letters, 2011An inward-fed two-arm Archimedean spiral antenna is proposed, which integrates a stripline feed network into one of the spiral arms. A broadband stripline tapered impedance transformer conformal to the spiral's winding provides a novel matching network between the input impedance of the spiral and the characteristic impedance of the stripline.
null Teng-Kai Chen, G H Huff
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Imbedded spiral antenna for endoscope
International Conference on Information Communication and Embedded Systems (ICICES2014), 2014This paper analyses the characteristics of dual spiral antenna with varying length. This antenna is operated in the lower band of the radio frequency range, since human body absorbs the microwave signals. Here the concept of multilayer substrate is used in order to reduce the size of the antenna. The existing system has several limitations.
Anila P. George, M. Sujatha
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