circular scan

circular scan

circular scan
A radar scan pattern in which a given point on the directed beam describes a circle in space with antennae at the center. This scan pattern is used in search radars and is distinguished by the regular intervals between successive illuminations of the target.
References in periodicals archive ?
The most commonly used reconstruction algorithms for electronics are based on the Feldkamp method (aka Feldkamp, Davis & Kress, or FDK, cone beam CT or circular scan CT).
Their algorithm seems effective and robust for 5 basic ASTs: circular scan, sector scan, raster scan, helical scan, and conical scan.
The ground-based search radar antenna will typically rotate 360 degrees in azimuth, a circular scan. This causes an EW receiver to see evenly spaced main beams as shown in Figure 4.
A 3.46mm circular scan is placed automatically around the optic disc and the information about peripapillary RNFL thickness is obtained.
In addition, depending on the size of the optic disc, the distance from the circular scan to the disc margin varies, and the RNFL becomes thinner as it gets away from the disc margin, which may result with some errors when measuring the thickness.
The Palmer scan is a circular scan that is moved linearly, as shown in Figure 3.
RNFL thickness was measured by scanning three consecutive 360 [degrees] circular scans with a diameter of 3.4 mm centered on the optic disc.
As previously described, infrared reflection images ([lambda] = 820 nm) and OCT B-scans ([lambda] = 870nm, 40,000 Ascans/s) of the dual-laser scanning systems of the Spectralis OCT were acquired simultaneously; 3.4mm-wide circular scans were taken (768 A-scans) around the optic disc.
(19) Three circular scans each of 2.4, 2.8 and 3.2 mm were taken 4 mm around optic disc in normal pupil size without dilatation.