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Directional antenna

About: Directional antenna is a research topic. Over the lifetime, 22896 publications have been published within this topic receiving 316044 citations.


Papers
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Journal ArticleDOI
TL;DR: The motivation for new mm-wave cellular systems, methodology, and hardware for measurements are presented and a variety of measurement results are offered that show 28 and 38 GHz frequencies can be used when employing steerable directional antennas at base stations and mobile devices.
Abstract: The global bandwidth shortage facing wireless carriers has motivated the exploration of the underutilized millimeter wave (mm-wave) frequency spectrum for future broadband cellular communication networks. There is, however, little knowledge about cellular mm-wave propagation in densely populated indoor and outdoor environments. Obtaining this information is vital for the design and operation of future fifth generation cellular networks that use the mm-wave spectrum. In this paper, we present the motivation for new mm-wave cellular systems, methodology, and hardware for measurements and offer a variety of measurement results that show 28 and 38 GHz frequencies can be used when employing steerable directional antennas at base stations and mobile devices.

6,708 citations

Journal ArticleDOI
01 Jul 1984

5,335 citations

Book
31 Oct 2000
TL;DR: Feeding Techniques and Modeling, Design and Analysis of Microstrip Antenna Arrays: Parallel and Series Feed Systems, and Theory and Design of Active Integrated Micro Strip Antenna Amplifiers.
Abstract: Microstrip Radiators: Various Microstrip Antenna Configurations. Feeding Techniques and Modeling. Applications. Radiation Field. Surface Waves and Photonic Band-Gap Structures. Analytical Models for Microstrip Antennas: Transmission Line Model. Cavity Model. Generalized Cavity Model. Multi-port Network Model (MNM). Radiation Fields. Aperture Admittance. Mutual Admittance. Model for Coaxial Probe in Microstrip Antennas. Comparison of Analytical Models. Full-Wave Analysis of Microstrip Antennas: Spectral Domain Full-Wave Analysis. Mixed-Potential Integral Equation Analysis. Finite-Difference Time Domain Analysis.Rectangular Microstrip Antenna: Models for Rectangular Patch Antenna. Design Considerations for Rectangular Patch Antennas. Tolerance Analysis of Rectangular Microstrip Antennas. Mechanical Tuning of Patch Antennas. Quarter-wave Rectangular Patch Antenna. Circular Disk and Ring Antennas: Analysis of a Circular Disk Microstrip Antenna. Design Considerations for Circular Disk Antennas. Semicircular Disk and Circular Sector Microstrip Antennas. Comparison Of Rectangular And Circular Disk Microstrip Antennas. Circular Ring or Annular Ring Microstrip Antenna. Circular Sector Microstrip Ring Antenna. Microstrip Ring Antennas of Non-Circular Shapes. Dipoles and Triangular Patch Antennas: Microstrip Dipole and Center-Fed Dipoles. Triangular Microstrip Patch Antenna. Design of an Equilateral Triangular Patch Antenna. Microstrip Slot Antennas: Microstrip-Fed Rectangular Slot Antennas. CPW-Fed Slot Antennas. Annular Slot Antennas. Tapered Slot Antennas (TSA). Comparison of Slot Antennas with Microstrip Antennas. Circularly Polarized Microstrip Antennas and Techniques: Various Types of Circularly Polarized Microstrip Antennas. Singly-Fed Circularly Polarized Microstrip Antennas. Dual-Orthagonal Feed Circularly Polarized Microstrip Antennas. Circularly Polarized Traveling-Wave Microstrip-Line Arrays. Bandwidth Enhancement Techniques. Sequentially Rotated Arrays. Broad-Banding of Microstrip Antennas: Effect of Substrate Parameters on Bandwidth. Selection of Suitable Patch Shape. Selection of Suitable Feeding Technique. Multi-Moding Techniques. Other Broadbanding Techniques. Multifrequency Operation. Loaded Microstrip Antennas and Applications: Polarization Diversity Using Microstrip Antennas. Frequency Agile Microstrip Antennas. Radiation Pattern Control of Microstrip Antennas. Loading Effect of a Short. Compact Patch Antennas. Planar Inverted F Antenna. Dual-Frequency Microstrip Antennas. Dual-Frequency Compact Microstrip Antennas. Active Integrated Microstrip Antennas: Classification of Active Integrated Microstrip Antennas. Theory and Design of Active Integrated Microstrip Antenna Oscillators. Theory and Design of Active Integrated Microstrip Antenna Amplifiers. Frequency Conversion Active Integrated Microstrip Antenna Theory and Design. Design and Analysis of Microstrip Antenna Arrays: Parallel and Series Feed Systems. Mutual Coupling. Design of Linear Arrays. Design of Planar Arrays. Monolithic Integrated Phased Arrays.

3,612 citations

Journal ArticleDOI
10 Jun 2005-Science
TL;DR: N nanometer-scale gold dipole antennas designed to be resonant at optical frequencies are fabricated, in contradiction to classical antenna theory but in qualitative accordance with computer simulations that take into account the finite metallic conductivity at optical frequency.
Abstract: We have fabricated nanometer-scale gold dipole antennas designed to be resonant at optical frequencies. On resonance, strong field enhancement in the antenna feed gap leads to white-light supercontinuum generation. The antenna length at resonance is considerably shorter than one-half the wavelength of the incident light. This is in contradiction to classical antenna theory but in qualitative accordance with computer simulations that take into account the finite metallic conductivity at optical frequencies. Because optical antennas link propagating radiation and confined/enhanced optical fields, they should find applications in optical characterization, manipulation of nanostructures, and optical information processing.

2,047 citations

Journal ArticleDOI
TL;DR: In this paper, the physical limitations of omni-directional antennas are considered and the potentiality of a broad band width of an antenna with the maximum dimension of 2a has been shown.
Abstract: The physical limitations of omni‐directional antennas are considered. With the use of the spherical wave functions to describe the field, the directivity gain G and the Q of an unspecified antenna are calculated under idealized conditions. To obtain the optimum performance, three criteria are used, (1) maximum gain for a given complexity of the antenna structure, (2) minimum Q, (3) maximum ratio of G/Q. It is found that an antenna of which the maximum dimension is 2a has the potentiality of a broad band width provided that the gain is equal to or less than 4a/λ. To obtain a gain higher than this value, the Q of the antenna increases at an astronomical rate. The antenna which has potentially the broadest band width of all omni‐directional antennas is one which has a radiation pattern corresponding to that of an infinitesimally small dipole.

1,954 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202390
2022237
2021132
2020216
2019296
2018349