scanning


scanning
In radar, the motion of the radar antenna assembly when searching for targets. Scanning usually follows a systematic pattern involving one or more of the following:
i. In horizontal scanning (or search lighting), the antenna is continuously rotated in an azimuth around the horizon or in a sector (sector scanning). This is used to find the azimuth of the targets and generate plan-position-indicator-scope displays.
ii. Vertical scanning is accomplished by holding the azimuth constant but varying the elevation angle of the antenna. It is used in height-finding radars to generate the relative-height-indicator-scope display.
iii. For conical scanning, a somewhat off-center radiating element is rotated while its parabolic reflectors remain fixed in position, so that the radiated beam generates a conically shaped volume with the antenna at the apex. It is used to determine an accurate bearing and the elevation angle of targets and is employed in automatic-tracking radars.
iv. In helical scanning (or spiral scanning), the azimuth and the elevation angle of the antenna are constantly varied, so that at a given distance from the radar the radiated beam generates the surface of a hemisphere. It is used for radio direction finding, in certain types of search radars, and in tracking radars to search areas for targets. See sector scan, conical scanning, helical scan, and height-finder radar.

Aviation dictionary. 2014.

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  • scanning — / skæniŋ/, it. / skan:ing/ s. ingl. [der. di (to ) scan esaminare ], usato in ital. al masch. (inform.) [analisi o campionamento di un immagine mediante cui essa è scomposta in elementi (detti pixel ) i quali vengono trasformati in segnali… …   Enciclopedia Italiana

  • scanning — /ˈskannin(g), ingl. ˈskænɪŋ/ [vc. ingl., da to scan «esaminare minuziosamente»] s. m. inv. scansione, scannerizzazione …   Sinonimi e Contrari. Terza edizione

  • scanning — scrutiny, examination, inspection, audit (see under SCRUTINIZE) Analogous words: study, application, *attention, concentration: *oversight, supervision, surveillance: analysis, dissection (see under ANALYZE) …   New Dictionary of Synonyms

  • Scanning — Scan|ning 〈[skæ̣nıŋ] n. 15; unz.〉 Bearbeitung mithilfe eines Scanners, das Einlesen; Sy Scan * * * Scan|ning [ skɛnɪŋ], das; [s], s [engl. scanning, zu: to scan, ↑ scannen] (Fachspr.): Untersuchung, Abtasten mithilfe eines Scanners. * * *… …   Universal-Lexikon

  • Scanning — Scan Scan (sk[a^]n), v. t. [imp. & p. p. {Scanned} (sk[a^]nd); p. pr. & vb. n. {Scanning}.] [L. scandere, scansum, to climb, to scan, akin to Skr. skand to spring, leap: cf. F. scander. Cf. {Ascend}, {Descend}, {Scale} a ladder.] 1. To mount by… …   The Collaborative International Dictionary of English

  • scanning — The act of imaging by traversing with an active or passive sensing device, often identified by the technology or device employed. transvaginal s. ultrasonography of the female pelvis with the transducer placed inside the …   Medical dictionary

  • scanning — Synonyms and related words: EDP, Stabreim, alliterative meter, analyzing, antispastic, automatic tracking, cadenced, classifying, collating, computer technology, computer typesetting, computing, dactylic, data processing, data retrieval, data… …   Moby Thesaurus

  • Scanning — Scan|ning das; [s] <aus gleichbed. engl. scanning> Untersuchung, Abtasten mithilfe eines Scanners …   Das große Fremdwörterbuch

  • scanning — scan·ning || skænɪŋ n. act of examining; act of glancing at quickly; act of converting an object or image into a digital image through the use of an optical scanner (Computers); examination of a body part though the use of medical imaging… …   English contemporary dictionary

  • scanning — skleidimas statusas T sritis automatika atitikmenys: angl. scan; scanning; sweep vok. Ablenkung, f; Abtastung, f rus. развёртка, f pranc. balayage, f …   Automatikos terminų žodynas