Matches in SemOpenAlex for { <https://semopenalex.org/work/W2171806315> ?p ?o ?g. }
Showing items 1 to 75 of
75
with 100 items per page.
- W2171806315 abstract "The principal characteristics of moderately superdirective normal mode helical dipoles are described both theoretically and experimentally. Use of a thin helix approximation permits integration of an assumed sinusoidal current distribution along a linear, foreshortened structure and yields a simple formula for the radiation field. Graphical displays of experimental and theoretical results illustrate that beamwidths of the order of 45deg with 22 db sidelobe suppression are available in dipoles which have a total length of only 0.6 wavelengths. In the theoretical analysis of helical dipoles, a linear relationship is assumed between the axial phase constant and frequency. The experimentally determined resonant length and mode of the structure define the proportionality constant, s, between phase velocity and free space velocity such that the linearized k-beta relationship used in radiation pattern analysis is beta = k/s . A method for determining the resonant length of tape helices from theoretical k-beta diagrams is described. The feasibility of utilizing helical dipoles as array elements, in applications where efficiency is secondary to size and directivity, is illustrated. The pattern multiplication technique is used in deriving an expression for the E -field for a two-element array. It is shown that with proper phasing of the fixed length elements, beamwidths in the range 30-40 degrees with front-to-back ratios in excess of 20 db over a pattern bandwidth representing 8% of the resonant frequency of an individual element are commonly available. A description and experimental data are provided for the tunable dipoles developed in order to achieve broadband operation. A hybrid is introduced in the array feed network so as to maintain a high front-to-back ratio over a broad range of frequencies. Experimental radiation patterns are displayed for a case in which the element phasing yields a front-to-back ratio which is independent of frequency. The overall dimensions of such moderately superdirective arrays are typically less than 0.2 times 0.8 wavelengths and can readily be used over a broad frequency range when tunable (variable length) dipoles and a hybrid junction are employed." @default.
- W2171806315 created "2016-06-24" @default.
- W2171806315 creator A5033801059 @default.
- W2171806315 creator A5036029818 @default.
- W2171806315 creator A5057522627 @default.
- W2171806315 date "2005-03-23" @default.
- W2171806315 modified "2023-09-24" @default.
- W2171806315 title "A superdirective array of normal mode helical dipoles" @default.
- W2171806315 cites W1853402621 @default.
- W2171806315 cites W1925698876 @default.
- W2171806315 cites W2127651846 @default.
- W2171806315 doi "https://doi.org/10.1109/irecon.1966.1147706" @default.
- W2171806315 hasPublicationYear "2005" @default.
- W2171806315 type Work @default.
- W2171806315 sameAs 2171806315 @default.
- W2171806315 citedByCount "6" @default.
- W2171806315 crossrefType "proceedings-article" @default.
- W2171806315 hasAuthorship W2171806315A5033801059 @default.
- W2171806315 hasAuthorship W2171806315A5036029818 @default.
- W2171806315 hasAuthorship W2171806315A5057522627 @default.
- W2171806315 hasConcept C120665830 @default.
- W2171806315 hasConcept C121332964 @default.
- W2171806315 hasConcept C151764478 @default.
- W2171806315 hasConcept C173523689 @default.
- W2171806315 hasConcept C189039984 @default.
- W2171806315 hasConcept C198394728 @default.
- W2171806315 hasConcept C21822782 @default.
- W2171806315 hasConcept C24890656 @default.
- W2171806315 hasConcept C26682833 @default.
- W2171806315 hasConcept C30475298 @default.
- W2171806315 hasConcept C32758168 @default.
- W2171806315 hasConcept C41008148 @default.
- W2171806315 hasConcept C62520636 @default.
- W2171806315 hasConcept C76155785 @default.
- W2171806315 hasConceptScore W2171806315C120665830 @default.
- W2171806315 hasConceptScore W2171806315C121332964 @default.
- W2171806315 hasConceptScore W2171806315C151764478 @default.
- W2171806315 hasConceptScore W2171806315C173523689 @default.
- W2171806315 hasConceptScore W2171806315C189039984 @default.
- W2171806315 hasConceptScore W2171806315C198394728 @default.
- W2171806315 hasConceptScore W2171806315C21822782 @default.
- W2171806315 hasConceptScore W2171806315C24890656 @default.
- W2171806315 hasConceptScore W2171806315C26682833 @default.
- W2171806315 hasConceptScore W2171806315C30475298 @default.
- W2171806315 hasConceptScore W2171806315C32758168 @default.
- W2171806315 hasConceptScore W2171806315C41008148 @default.
- W2171806315 hasConceptScore W2171806315C62520636 @default.
- W2171806315 hasConceptScore W2171806315C76155785 @default.
- W2171806315 hasLocation W21718063151 @default.
- W2171806315 hasOpenAccess W2171806315 @default.
- W2171806315 hasPrimaryLocation W21718063151 @default.
- W2171806315 hasRelatedWork W1593708556 @default.
- W2171806315 hasRelatedWork W1777640482 @default.
- W2171806315 hasRelatedWork W1972990766 @default.
- W2171806315 hasRelatedWork W2022641998 @default.
- W2171806315 hasRelatedWork W2070196506 @default.
- W2171806315 hasRelatedWork W2089231806 @default.
- W2171806315 hasRelatedWork W2089807652 @default.
- W2171806315 hasRelatedWork W2111230466 @default.
- W2171806315 hasRelatedWork W2111683547 @default.
- W2171806315 hasRelatedWork W2129802891 @default.
- W2171806315 hasRelatedWork W2162387081 @default.
- W2171806315 hasRelatedWork W2164604943 @default.
- W2171806315 hasRelatedWork W2908664053 @default.
- W2171806315 hasRelatedWork W2970298329 @default.
- W2171806315 hasRelatedWork W3010354926 @default.
- W2171806315 hasRelatedWork W3148076329 @default.
- W2171806315 hasRelatedWork W1670205299 @default.
- W2171806315 hasRelatedWork W209025381 @default.
- W2171806315 hasRelatedWork W2136039119 @default.
- W2171806315 hasRelatedWork W2197265475 @default.
- W2171806315 isParatext "false" @default.
- W2171806315 isRetracted "false" @default.
- W2171806315 magId "2171806315" @default.
- W2171806315 workType "article" @default.